A social realist analysis of the professional identity formation of lecturers emerging from completing professional development at a South African research-intensive university
- Authors: Adams, Anthea
- Date: 2024-10-11
- Subjects: Identity (Psychology) in education , Academic development , Staff development , Social realism , Critical realism , Scholarship of teaching and learning , Education, Higher South Africa
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466372 , vital:76722 , DOI https://doi.org/10.21504/10962/466372
- Description: This doctoral study is part of a Department of Higher Education and Training (DHET) capacity development project, Phakamisa. Using Margaret Archer's Social Realism as a substantive theory and methodological tool and Roy Bhaskar's Critical Realism as a meta-theory, I was able to identify and explain the interplay between the structural, cultural and agential mechanisms within a professional development course that enabled or constrained the emergence of lecturers' professional academic identities. My research participants are fourteen lecturers who completed the Postgraduate Diploma in Higher Education (PGDip HE) at Rhodes University between 2007 and 2017. Social Realism's explanatory methodologies, analytical dualism, and the morphogenetic cycle allowed me to provide causal explanations and account for the historicity of the emergence of lecturers' professional academic identities as teachers. A qualitative research design involving case study research allowed me to search for generative mechanisms to understand and explain the conditioning influence of often unobservable phenomena and underlying mechanisms in developing lecturers' identities as teachers in a research-intensive university. As strong social actors imbued with power and material resources, university leadership should consider the constraining influence of contextual conditions, such as the hegemony of disciplinary research versus research in the Scholarship of Teaching and Learning (SoTL). The socio-cultural (S-C) interactions of the fourteen lecturers (agents) signal the possibilities for structural, cultural and agential morphogenesis when agents choose to exercise their agency, i.e., their personal emergent properties (PEPs) to mediate prevalent structural and cultural emergent properties (SEPs and CEPs) enabling or constraining their personal projects. Lecturers' personal projects are the courses of action they intentionally engage in as they strive to establish sustainable yet evolving practices as teachers in their disciplines. This thesis shows that exercising their PEPs involves subjective reflexivity and transforming from primary agents to corporate agents due to collective action and alliances with like-minded peers and colleagues to shape the teaching and learning agenda in their respective departments and the broader higher education context. Triple morphogenesis of lecturers' agency occurred through their realisation as social actors. It signified the formation of their professional identities as teachers and how they uniquely embodied and enacted their teacher roles. , Hierdie doktorale studie is deel van 'n Departement van Hoër Onderwys en Opleiding (DHOO) kapasiteitsontwikkelingsprojek, naamlik Phakamisa. Deur gebruik te maak van Margaret Archer se Sosiale Realisme ("Social Realism") as 'n substantiewe teorie en metodologiese instrument, en Roy Bhaskar se Kritiese Realisme ("Critical Realism") as 'n metateorie, was ek in staat om die wisselwerking tussen die strukturele, kulturele en agentiese meganismes binne 'n professionele ontwikkelingskursus te identifiseer en te verduidelik wat die ontstaan van dosente se professionele akademiese identiteite moontlik gemaak of beperk het. Die deelnemers in my navorsing is veertien dosente wat die Nagraadse Diploma in Hoër Onderwys (NGDip HO) aan Rhodes Universiteit tussen 2007 en 2017 voltooi het. Sosiale Realisme se verklarende metodologieë, analitiese dualisme en die morfogenetiese siklus het my toegelaat om oorsaaklike verklarings te verskaf en die historisiteit van die ontstaan van dosente se professionele akademiese identiteite as onderwysers te verantwoord. ’n Kwalitatiewe navorsingsontwerp wat gevallestudienavorsing behels het, het my toegelaat om na generatiewe meganismes te soek om die kondisionerende invloed van dikwels onwaarneembare verskynsels en onderliggende meganismes in die ontwikkeling van dosente se identiteit as onderwysers in ’n navorsingsintensiewe universiteit te verstaan en te verduidelik. As sterk sosiale rolspelers deurdrenk met mag en materiële hulpbronne, behoort universiteitsleierskap die beperkende invloed van kontekstuele toestande, soos die hegemonie van dissiplinêre navorsing versus navorsing in die Akademieskap van Onderrig en Leer (AvOL, of in Engels "Scholarship of Teaching and Learning", afgekort na SoTL) in ag te neem. Die sosiokulturele (S-K) interaksie van die veertien dosente (agente) dui op die moontlikhede vir strukturele, kulturele en agentiale morfogenese wanneer agente doelbewus kies om hul agentskap uit te oefen, dit wil sê hul persoonlike ontluikende eienskappe (in Engels "personal emergent properties", afgekort na PEPs) om heersende strukturele en kulturele ontluikende eienskappe te bemiddel (in Engels "cultural emergent properties", afgekort na CEPs) wat hul persoonlike projekte moontlik maak of beperk. Dosente se persoonlike projekte is die aksies wat hulle doelbewus aangepak het terwyl hulle daarna gestreef het om volhoubare dog ontwikkelende praktyke as onderwysers in hul dissiplines te vestig. Hierdie tesis dui aan dat die uitoefening van hul persoonlike ontluikende eienskappe ("PEPs") behels subjektiewe refleksiwiteit en transformasie van primêre agente na korporatiewe agente as gevolg van kollektiewe optrede en alliansies met eendersdenkende eweknieë en kollegas om die onderrigen leeragenda in hul onderskeie departemente en die breër hoëronderwyskonteks te beïnvloed. Drievoudige morfogenese van dosente se agentskap het plaasgevind deur hul verwesenliking as sosiale rolspelers. Dit het die vorming van hul professionele identiteite as onderwysers aangedui en die unieke manier hoe hulle hul onderwyserrolle interpreteer en uitleef. , Thesis (PhD) -- Faculty of Education, Centre for Higher Education Research, Teaching and Learning, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Adams, Anthea
- Date: 2024-10-11
- Subjects: Identity (Psychology) in education , Academic development , Staff development , Social realism , Critical realism , Scholarship of teaching and learning , Education, Higher South Africa
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466372 , vital:76722 , DOI https://doi.org/10.21504/10962/466372
- Description: This doctoral study is part of a Department of Higher Education and Training (DHET) capacity development project, Phakamisa. Using Margaret Archer's Social Realism as a substantive theory and methodological tool and Roy Bhaskar's Critical Realism as a meta-theory, I was able to identify and explain the interplay between the structural, cultural and agential mechanisms within a professional development course that enabled or constrained the emergence of lecturers' professional academic identities. My research participants are fourteen lecturers who completed the Postgraduate Diploma in Higher Education (PGDip HE) at Rhodes University between 2007 and 2017. Social Realism's explanatory methodologies, analytical dualism, and the morphogenetic cycle allowed me to provide causal explanations and account for the historicity of the emergence of lecturers' professional academic identities as teachers. A qualitative research design involving case study research allowed me to search for generative mechanisms to understand and explain the conditioning influence of often unobservable phenomena and underlying mechanisms in developing lecturers' identities as teachers in a research-intensive university. As strong social actors imbued with power and material resources, university leadership should consider the constraining influence of contextual conditions, such as the hegemony of disciplinary research versus research in the Scholarship of Teaching and Learning (SoTL). The socio-cultural (S-C) interactions of the fourteen lecturers (agents) signal the possibilities for structural, cultural and agential morphogenesis when agents choose to exercise their agency, i.e., their personal emergent properties (PEPs) to mediate prevalent structural and cultural emergent properties (SEPs and CEPs) enabling or constraining their personal projects. Lecturers' personal projects are the courses of action they intentionally engage in as they strive to establish sustainable yet evolving practices as teachers in their disciplines. This thesis shows that exercising their PEPs involves subjective reflexivity and transforming from primary agents to corporate agents due to collective action and alliances with like-minded peers and colleagues to shape the teaching and learning agenda in their respective departments and the broader higher education context. Triple morphogenesis of lecturers' agency occurred through their realisation as social actors. It signified the formation of their professional identities as teachers and how they uniquely embodied and enacted their teacher roles. , Hierdie doktorale studie is deel van 'n Departement van Hoër Onderwys en Opleiding (DHOO) kapasiteitsontwikkelingsprojek, naamlik Phakamisa. Deur gebruik te maak van Margaret Archer se Sosiale Realisme ("Social Realism") as 'n substantiewe teorie en metodologiese instrument, en Roy Bhaskar se Kritiese Realisme ("Critical Realism") as 'n metateorie, was ek in staat om die wisselwerking tussen die strukturele, kulturele en agentiese meganismes binne 'n professionele ontwikkelingskursus te identifiseer en te verduidelik wat die ontstaan van dosente se professionele akademiese identiteite moontlik gemaak of beperk het. Die deelnemers in my navorsing is veertien dosente wat die Nagraadse Diploma in Hoër Onderwys (NGDip HO) aan Rhodes Universiteit tussen 2007 en 2017 voltooi het. Sosiale Realisme se verklarende metodologieë, analitiese dualisme en die morfogenetiese siklus het my toegelaat om oorsaaklike verklarings te verskaf en die historisiteit van die ontstaan van dosente se professionele akademiese identiteite as onderwysers te verantwoord. ’n Kwalitatiewe navorsingsontwerp wat gevallestudienavorsing behels het, het my toegelaat om na generatiewe meganismes te soek om die kondisionerende invloed van dikwels onwaarneembare verskynsels en onderliggende meganismes in die ontwikkeling van dosente se identiteit as onderwysers in ’n navorsingsintensiewe universiteit te verstaan en te verduidelik. As sterk sosiale rolspelers deurdrenk met mag en materiële hulpbronne, behoort universiteitsleierskap die beperkende invloed van kontekstuele toestande, soos die hegemonie van dissiplinêre navorsing versus navorsing in die Akademieskap van Onderrig en Leer (AvOL, of in Engels "Scholarship of Teaching and Learning", afgekort na SoTL) in ag te neem. Die sosiokulturele (S-K) interaksie van die veertien dosente (agente) dui op die moontlikhede vir strukturele, kulturele en agentiale morfogenese wanneer agente doelbewus kies om hul agentskap uit te oefen, dit wil sê hul persoonlike ontluikende eienskappe (in Engels "personal emergent properties", afgekort na PEPs) om heersende strukturele en kulturele ontluikende eienskappe te bemiddel (in Engels "cultural emergent properties", afgekort na CEPs) wat hul persoonlike projekte moontlik maak of beperk. Dosente se persoonlike projekte is die aksies wat hulle doelbewus aangepak het terwyl hulle daarna gestreef het om volhoubare dog ontwikkelende praktyke as onderwysers in hul dissiplines te vestig. Hierdie tesis dui aan dat die uitoefening van hul persoonlike ontluikende eienskappe ("PEPs") behels subjektiewe refleksiwiteit en transformasie van primêre agente na korporatiewe agente as gevolg van kollektiewe optrede en alliansies met eendersdenkende eweknieë en kollegas om die onderrigen leeragenda in hul onderskeie departemente en die breër hoëronderwyskonteks te beïnvloed. Drievoudige morfogenese van dosente se agentskap het plaasgevind deur hul verwesenliking as sosiale rolspelers. Dit het die vorming van hul professionele identiteite as onderwysers aangedui en die unieke manier hoe hulle hul onderwyserrolle interpreteer en uitleef. , Thesis (PhD) -- Faculty of Education, Centre for Higher Education Research, Teaching and Learning, 2024
- Full Text:
- Date Issued: 2024-10-11
A scoping review on problematic Internet use and Substance Use Disorder among men
- Authors: Adolph, Miché Tania
- Date: 2024-10-11
- Subjects: Internet addiction , Substance abuse , Men Mental health , Scoping review protocol , Compulsive behavior Sex differences
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/465788 , vital:76653
- Description: Problematic Internet Use (PIU) and Substance Use Disorder (SUD) interact in complex ways that influence the current mental health landscape. Concurrently, the advent of the digital era has presented new difficulties, one of which is the emergence of problematic internet use as a significant issue that negatively impacts mental health. The increasing popularity of internet use has led to an increasing number of reports highlighting the potential negative consequences of overuse, such as substance use. Thus, the study aimed to synthesise literature on problematic internet use and substance use disorder, including the way in which they affect men, given that prior research has predominantly focused on women. The methods employed follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) which is largely based on a PRISMA statement and checklist, the JBI methodological guidance, and other approaches for undertaking scoping reviews. A total of 16 studies were eligible for final review, and the themes identified from the reviewed studies were obtained using Braun and Clarke’s thematic analysis. An analysis of the articles showed a large focus on gender differences in addiction patterns, vulnerability to problematic internet use across age groups, associations between substance use and behavioural addictions, problematic internet use and mental health disorders, the psychological consequences of problematic internet use and substance use disorders, and the various risk factors associated with the development of problematic internet use and substance use disorder. A clear understanding and conceptualisation of this behavioural addiction is vital, including the development and utilisation of appropriate and validated diagnostic and screening tools to measure its presence and, in turn, address it as an emerging mental health disorder. Focus should be given to the assessment of problematic internet use by distinguishing the two different forms, namely the generalised and specific forms of problematic internet use. Additionally, given that there were very few to no qualitative studies conducted on the topic of problematic internet use, much less addressing the possible association with substance use disorder, an assessment of the individual’s experience, especially that of men, is lacking. Future research could therefore aim to incorporate more qualitative studies to address the above. Further research is also needed to clarify the nature of the relationship between problematic internet use and substance use disorder for the purpose of establishing possible causality, including the neurobiological substrates involved. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Adolph, Miché Tania
- Date: 2024-10-11
- Subjects: Internet addiction , Substance abuse , Men Mental health , Scoping review protocol , Compulsive behavior Sex differences
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/465788 , vital:76653
- Description: Problematic Internet Use (PIU) and Substance Use Disorder (SUD) interact in complex ways that influence the current mental health landscape. Concurrently, the advent of the digital era has presented new difficulties, one of which is the emergence of problematic internet use as a significant issue that negatively impacts mental health. The increasing popularity of internet use has led to an increasing number of reports highlighting the potential negative consequences of overuse, such as substance use. Thus, the study aimed to synthesise literature on problematic internet use and substance use disorder, including the way in which they affect men, given that prior research has predominantly focused on women. The methods employed follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) which is largely based on a PRISMA statement and checklist, the JBI methodological guidance, and other approaches for undertaking scoping reviews. A total of 16 studies were eligible for final review, and the themes identified from the reviewed studies were obtained using Braun and Clarke’s thematic analysis. An analysis of the articles showed a large focus on gender differences in addiction patterns, vulnerability to problematic internet use across age groups, associations between substance use and behavioural addictions, problematic internet use and mental health disorders, the psychological consequences of problematic internet use and substance use disorders, and the various risk factors associated with the development of problematic internet use and substance use disorder. A clear understanding and conceptualisation of this behavioural addiction is vital, including the development and utilisation of appropriate and validated diagnostic and screening tools to measure its presence and, in turn, address it as an emerging mental health disorder. Focus should be given to the assessment of problematic internet use by distinguishing the two different forms, namely the generalised and specific forms of problematic internet use. Additionally, given that there were very few to no qualitative studies conducted on the topic of problematic internet use, much less addressing the possible association with substance use disorder, an assessment of the individual’s experience, especially that of men, is lacking. Future research could therefore aim to incorporate more qualitative studies to address the above. Further research is also needed to clarify the nature of the relationship between problematic internet use and substance use disorder for the purpose of establishing possible causality, including the neurobiological substrates involved. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
- Full Text:
- Date Issued: 2024-10-11
A social realist analysis of health policy development: interests, ideas and community pharmacists
- Authors: Allan, Lucie
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466328 , vital:76718
- Description: Access restricted. Expected release in 2026. , Thesis (PhD) -- Faculty of Pharmacy, Pharmacy, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Allan, Lucie
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466328 , vital:76718
- Description: Access restricted. Expected release in 2026. , Thesis (PhD) -- Faculty of Pharmacy, Pharmacy, 2024
- Full Text:
- Date Issued: 2024-10-11
Exploring self-directed continuous professional development for English Language teachers in selected Namibian secondary schools
- Amakutuwa, Hilma Ndesheetelwa Mwalengwa
- Authors: Amakutuwa, Hilma Ndesheetelwa Mwalengwa
- Date: 2024-10-11
- Subjects: English language Study and teaching Namibia , English teachers Namibia , Continuing professional development , Self-managed learning , Reflective practice
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463538 , vital:76418 , https://doi.org/10.21504/RUR.28955744.v1
- Description: Continuous professional development (CPD) for teachers, with all its diverse notions, has been noted and articulated in various policy documents in Namibia, and is understood as in-service training and professional development for teachers to improve learning outcomes. In Namibia, challenges have been experienced with the performance of learners in English as a Second Language (ESL) at the national level, and teacher professional development could be one way of changing the status quo. However, in answer to the call from the Namibian Ministry of Education Arts and Culture for a more idiosyncratic orientation, limited literature was found on how ESL teachers use self-directed learning (SDL) to shape their CPD activities. Thus, the purpose of this study was to address this gap by exploring the self-directed CPD needs of English Language teachers in selected Namibian secondary schools. The study was oriented to theoretical insights from SDL, reflective practice and social constructivism. Through the use of a qualitative approach, the study employed an exploratory case study research design. Semi-structured interviews and focus group discussions were used to generate data from eight selected Grade 8 to 12 ESL teachers in the Khomas region of Namibia. The data gathered were analysed using an inductive thematic framework. The findings of the study indicate that ESL teachers are faced with a myriad of challenges ranging from classroom experiences, the type of learners they work with and the support system available at school, regional and national level. The study found that due to changing education paradigms, ESL teachers need to broaden their knowledge base in specialised education and systematic professional interventions at school level. They indicated that this would help learners with challenges in reading, writing and comprehension to improve their skills in ESL classrooms. They further emphasised the necessity for mentors, education specialists, systematic schools and circuit based collaborative CPD, as well as more support from school heads and regional ESL senior education officers, which is an area that is inadequately managed. Finally, they pointed out that in order to make their ESL classes engaging and enjoyable, teachers needed to have a strong foundation in ICT education. This foundation can be leveraged to create resources that are now lacking. The findings have implications for ESL teachers, school administrators, education specialists and policymakers, as they provide insights and recommendations for enhancing ESL education practices. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Amakutuwa, Hilma Ndesheetelwa Mwalengwa
- Date: 2024-10-11
- Subjects: English language Study and teaching Namibia , English teachers Namibia , Continuing professional development , Self-managed learning , Reflective practice
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463538 , vital:76418 , https://doi.org/10.21504/RUR.28955744.v1
- Description: Continuous professional development (CPD) for teachers, with all its diverse notions, has been noted and articulated in various policy documents in Namibia, and is understood as in-service training and professional development for teachers to improve learning outcomes. In Namibia, challenges have been experienced with the performance of learners in English as a Second Language (ESL) at the national level, and teacher professional development could be one way of changing the status quo. However, in answer to the call from the Namibian Ministry of Education Arts and Culture for a more idiosyncratic orientation, limited literature was found on how ESL teachers use self-directed learning (SDL) to shape their CPD activities. Thus, the purpose of this study was to address this gap by exploring the self-directed CPD needs of English Language teachers in selected Namibian secondary schools. The study was oriented to theoretical insights from SDL, reflective practice and social constructivism. Through the use of a qualitative approach, the study employed an exploratory case study research design. Semi-structured interviews and focus group discussions were used to generate data from eight selected Grade 8 to 12 ESL teachers in the Khomas region of Namibia. The data gathered were analysed using an inductive thematic framework. The findings of the study indicate that ESL teachers are faced with a myriad of challenges ranging from classroom experiences, the type of learners they work with and the support system available at school, regional and national level. The study found that due to changing education paradigms, ESL teachers need to broaden their knowledge base in specialised education and systematic professional interventions at school level. They indicated that this would help learners with challenges in reading, writing and comprehension to improve their skills in ESL classrooms. They further emphasised the necessity for mentors, education specialists, systematic schools and circuit based collaborative CPD, as well as more support from school heads and regional ESL senior education officers, which is an area that is inadequately managed. Finally, they pointed out that in order to make their ESL classes engaging and enjoyable, teachers needed to have a strong foundation in ICT education. This foundation can be leveraged to create resources that are now lacking. The findings have implications for ESL teachers, school administrators, education specialists and policymakers, as they provide insights and recommendations for enhancing ESL education practices. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2024
- Full Text:
- Date Issued: 2024-10-11
Meerkat polarimetric observations of Pictor A
- Authors: Andati, Lexy Acherwa Livoyi
- Date: 2024-10-11
- Subjects: Polarimetry , MeerKAT , Radio astronomy , Radio galaxies , Cosmic magnetic fields , Pictor A
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466896 , vital:76796 , DOI https://doi.org/10.21504/10962/466896
- Description: Pictor A is one of the brightest and closest radio galaxies in the Southern Hemisphere, offering a unique opportunity for in-depth studies of the astrophysics of radio galaxies and their interactions with their environments. Many multi-wavelength studies of this source have been done. However, the most comprehensive radio frequency study of Pictor A’s morphological components was conducted by Perley et al. (1997) using the Very Large Array (VLA) located in the Northern Hemisphere. To date, that work remains the most detailed study of Pictor A. In this thesis, we conducted a spectropolarimetric study of Pictor A using new L-band data obtained in 2019 from the high-sensitivity MeerKAT telescope, which provides the deepest and most sensitive data of this source at a continuous and finely sampled frequency coverage in the L-band. Thus, due to Pictor A’s proximity, high luminosity, and the MeerKAT’s high sensitivity, the data delivers a unique dataset for our study of the magnetic field structure of Pictor A and allows for a detailed study of the source’s morphological structures. We presented the steps taken during our calibration and data reduction, leading to polarimetryready images. During the first phase of calibration, excision of data corrupted by instrumental effects and radio frequency interference (RFI) resulted in only 50% useable data. Pictor A’s exceptionally bright western hotspot introduced significant artefacts in our images, mitigated in the second calibration phase through direction-dependent calibration. The calibrated data resulted in a multi-frequency synthesis (MFS) Stokes I image of Pictor A at 7.5′′ in resolution with an offsource RMS noise of ∼22 𝜇Jy/beam. The off-source noise in the Stokes Q and U sub-band images ranged between 95 – 278 𝜇Jy/beam and 41 – 233 𝜇Jy/beam, respectively. Additionally, we briefly highlighted the effects of RFI in the L-band on polarimetry, particularly the considerable loss of 𝜆2 coverage of ∼50%. All the calibration recipes used for this work were made available in this thesis. Using Pictor A’s data as a testbed, we introduced a Python-based tool, Smops, developed during the calibration stages of our work. Smops was designed for an intermediate post-processing step. It interpolates input sub-band model FITS images (such as those produced by WSClean) into finely channelized sub-band model FITS images, thereby generating model images at a higher frequency resolution. Smops reduces the need to generate model images with numerous sub-bands, which is computationally intensive and time-consuming. A higher resolution in frequency of the models facilitates more efficient model subtraction during self-calibration. We then presented the total intensity features of Pictor A, which the calibrated data reveals. We confirmed the presence of Pictor A’s radio jet extending from its core to the western hotspot. Notably, this feature, faint and barely visible in previous radio images, is now distinctly observed. The counterjet remains undetectable. Furthermore, we demonstrated the coexistence of radio emission, which is expected to align with previously observed X-ray diffuse emission. This observation confirmed the inverse Compton origin of Pictor A’s lobe emission. Employing the RM-synthesis technique for the spectropolarimetric study of Pictor A, we identified a relatively consistent rotation measure (RM) across its lobes, with an average RM of 48.06 ± 10.19 rad m−2 for the entire source. However, the eastern lobe displayed a wider RM dispersion than the western lobe. Moreover, our study affirmed the depolarisation asymmetry previously observed between the western and eastern lobes of Pictor A, where the eastern lobe exhibited significantly more depolarisation than its western counterpart. Most lines-of-sight across Pictor A displayed single-peaked Faraday spectra, indicating a single Faraday rotating screen. However, we also noted that several lines-of-sight (∼23%) showed more than one Faraday peak. An investigation into the ii possible causes of the multiple observed peaks using QU-fitting suggested that there is a possibility of a Faraday thick structure or multiple Faraday components along these paths. Furthermore, we estimated a Galactic RM contribution towards Pictor A of 23.57 ± 10.87 rad m−2. We concluded that while our Galaxy may contribute to the mean RM for this source, it cannot explain smallscale fluctuations, which suggests that some fraction of the observed rotation measures could result from some inter-galactic medium, X-ray gas near the shock boundary region (the sheath), or other unknown intervening material. We introduced Scrappy, a Python-based tool tailored for processing lines-of-sight data. Scrappy yields RM-synthesis diagnostic data products such as the data associated with each line-of-sight, and their corresponding plots in 𝜙-space (e.g. cleaned and dirty Faraday spectra and RMTF), and 𝜆2-space (e.g. the fractional polarisation, and Stokes Q and U ). Scrappy further avails a Bash-based pipeline, showrunner.sh, that processes input sub-band Stokes images, automatically selects usable sub-bands, stacks images into Stokes cubes, generates lines-of-sight, processes their corresponding data, and produces diagnostic plots. Additionally, it creates per-pixel maps of fractional polarisation, RM, polarisation angle, peak FDF, and linear polarised intensity. The pipeline ensures reproducibility. To visualise the diagnostic plots from Scrappy, we developed PolarVis, a simple web-based tool that enables the visualisation of diagnostic plots associated with each available line-of-sight, thus facilitating the quick exploration of interesting lines-of-sight in regions across this source. This tool facilitates the visualisation of polarisation behaviour for specific lines-of-sight, enabling quick identification of interesting regions of the source. Furthermore, its interactivity promotes the exploration of line-of-sight data. Availing data to the public with this tool permits validation or comparison of results from varying techniques, hence fostering a sense of transparency. As a result, the 2389 lines-of-sight of Pictor A are presented using PolarVis and are available at https://pica.ratt.center. , Thesis (PhD) -- Faculty of Science, Physics and Electronics, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Andati, Lexy Acherwa Livoyi
- Date: 2024-10-11
- Subjects: Polarimetry , MeerKAT , Radio astronomy , Radio galaxies , Cosmic magnetic fields , Pictor A
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466896 , vital:76796 , DOI https://doi.org/10.21504/10962/466896
- Description: Pictor A is one of the brightest and closest radio galaxies in the Southern Hemisphere, offering a unique opportunity for in-depth studies of the astrophysics of radio galaxies and their interactions with their environments. Many multi-wavelength studies of this source have been done. However, the most comprehensive radio frequency study of Pictor A’s morphological components was conducted by Perley et al. (1997) using the Very Large Array (VLA) located in the Northern Hemisphere. To date, that work remains the most detailed study of Pictor A. In this thesis, we conducted a spectropolarimetric study of Pictor A using new L-band data obtained in 2019 from the high-sensitivity MeerKAT telescope, which provides the deepest and most sensitive data of this source at a continuous and finely sampled frequency coverage in the L-band. Thus, due to Pictor A’s proximity, high luminosity, and the MeerKAT’s high sensitivity, the data delivers a unique dataset for our study of the magnetic field structure of Pictor A and allows for a detailed study of the source’s morphological structures. We presented the steps taken during our calibration and data reduction, leading to polarimetryready images. During the first phase of calibration, excision of data corrupted by instrumental effects and radio frequency interference (RFI) resulted in only 50% useable data. Pictor A’s exceptionally bright western hotspot introduced significant artefacts in our images, mitigated in the second calibration phase through direction-dependent calibration. The calibrated data resulted in a multi-frequency synthesis (MFS) Stokes I image of Pictor A at 7.5′′ in resolution with an offsource RMS noise of ∼22 𝜇Jy/beam. The off-source noise in the Stokes Q and U sub-band images ranged between 95 – 278 𝜇Jy/beam and 41 – 233 𝜇Jy/beam, respectively. Additionally, we briefly highlighted the effects of RFI in the L-band on polarimetry, particularly the considerable loss of 𝜆2 coverage of ∼50%. All the calibration recipes used for this work were made available in this thesis. Using Pictor A’s data as a testbed, we introduced a Python-based tool, Smops, developed during the calibration stages of our work. Smops was designed for an intermediate post-processing step. It interpolates input sub-band model FITS images (such as those produced by WSClean) into finely channelized sub-band model FITS images, thereby generating model images at a higher frequency resolution. Smops reduces the need to generate model images with numerous sub-bands, which is computationally intensive and time-consuming. A higher resolution in frequency of the models facilitates more efficient model subtraction during self-calibration. We then presented the total intensity features of Pictor A, which the calibrated data reveals. We confirmed the presence of Pictor A’s radio jet extending from its core to the western hotspot. Notably, this feature, faint and barely visible in previous radio images, is now distinctly observed. The counterjet remains undetectable. Furthermore, we demonstrated the coexistence of radio emission, which is expected to align with previously observed X-ray diffuse emission. This observation confirmed the inverse Compton origin of Pictor A’s lobe emission. Employing the RM-synthesis technique for the spectropolarimetric study of Pictor A, we identified a relatively consistent rotation measure (RM) across its lobes, with an average RM of 48.06 ± 10.19 rad m−2 for the entire source. However, the eastern lobe displayed a wider RM dispersion than the western lobe. Moreover, our study affirmed the depolarisation asymmetry previously observed between the western and eastern lobes of Pictor A, where the eastern lobe exhibited significantly more depolarisation than its western counterpart. Most lines-of-sight across Pictor A displayed single-peaked Faraday spectra, indicating a single Faraday rotating screen. However, we also noted that several lines-of-sight (∼23%) showed more than one Faraday peak. An investigation into the ii possible causes of the multiple observed peaks using QU-fitting suggested that there is a possibility of a Faraday thick structure or multiple Faraday components along these paths. Furthermore, we estimated a Galactic RM contribution towards Pictor A of 23.57 ± 10.87 rad m−2. We concluded that while our Galaxy may contribute to the mean RM for this source, it cannot explain smallscale fluctuations, which suggests that some fraction of the observed rotation measures could result from some inter-galactic medium, X-ray gas near the shock boundary region (the sheath), or other unknown intervening material. We introduced Scrappy, a Python-based tool tailored for processing lines-of-sight data. Scrappy yields RM-synthesis diagnostic data products such as the data associated with each line-of-sight, and their corresponding plots in 𝜙-space (e.g. cleaned and dirty Faraday spectra and RMTF), and 𝜆2-space (e.g. the fractional polarisation, and Stokes Q and U ). Scrappy further avails a Bash-based pipeline, showrunner.sh, that processes input sub-band Stokes images, automatically selects usable sub-bands, stacks images into Stokes cubes, generates lines-of-sight, processes their corresponding data, and produces diagnostic plots. Additionally, it creates per-pixel maps of fractional polarisation, RM, polarisation angle, peak FDF, and linear polarised intensity. The pipeline ensures reproducibility. To visualise the diagnostic plots from Scrappy, we developed PolarVis, a simple web-based tool that enables the visualisation of diagnostic plots associated with each available line-of-sight, thus facilitating the quick exploration of interesting lines-of-sight in regions across this source. This tool facilitates the visualisation of polarisation behaviour for specific lines-of-sight, enabling quick identification of interesting regions of the source. Furthermore, its interactivity promotes the exploration of line-of-sight data. Availing data to the public with this tool permits validation or comparison of results from varying techniques, hence fostering a sense of transparency. As a result, the 2389 lines-of-sight of Pictor A are presented using PolarVis and are available at https://pica.ratt.center. , Thesis (PhD) -- Faculty of Science, Physics and Electronics, 2024
- Full Text:
- Date Issued: 2024-10-11
Immobilisation of an Aspergillus niger derived endo-1,4-β-mannanase, Man26A, for the production of prebiotic mannooligosaccharides from soybean meal
- Authors: Anderson, Amy Sage
- Date: 2024-10-11
- Subjects: Aspergillus niger , Soybean meal , Mannosidases , Oligosaccharides , Immobilized microorganisms
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463897 , vital:76455
- Description: This study investigated the potential for antibiotic alternatives in the form of prebiotics produced from the enzymatic breakdown of soybean meal (SBM). This study first investigated the immobilisation of an endo-1,4-β-mannanase derived from Aspergillus niger on glutaraldehyde-activated chitosan nanoparticles (CTS) and glutaraldehyde-activated chitosan-coated magnetic Fe3O4 nanoparticles (MAGS-CTS) - which could be effectively used to hydrolyse the galactomannan contained in SBM in a recyclable manner. The mannooligosaccharides (MOS) produced from the enzymatic digestion of SBM were then analysed for their prebiotic and antimicrobial capabilities to determine whether the strategy employed was capable of promoting and inhibiting probiotic and pathogenic growth, respectively. An Aspergillus niger endo-1,4-β-mannanase, Man26A, was confirmed by FTIR (Fourier-transform infrared spectroscopy) and XRD (X-ray powder diffraction) to be immobilised onto CTS and MAGS-CTS by covalent bonding. The immobilisation (%) and activity yields (%) were 81.14% and 35.45%, and 55.75% and 21.17%, respectively. The biochemical properties (pH and temperature optima, and temperature stability) of both the free CTS and MAGS-CTS immobilised Man26A enzymes were evaluated, with the pH optima shifting to a lower pH range after immobilisation (pH 2.0 – 3.0 vs. 5.0), while the temperature optima and stabilities remaining unchanged (at 60°C). CTS and free enzymes exhibited identical thermal stabilities, maintaining 100% activity for the first 6 hours at 55°C, while MAGS-CTS showed an immediate drop in relative activity after the first 30 minutes of incubation. Recyclability analysis revealed that CTS could be effectively reused for six reaction cycles, while the MAGS-CTS immobilised enzyme could only be used once. Both enzymes could be efficiently stored at 4ºC, showing a relative residual activity of 73% after 120 hours of storage. Substrate kinetic analysis showed that the free enzyme had the highest catalytic capabilities in hydrolysing locust bean gum (LBG), with the CTS immobilised enzyme was the most efficient in hydrolysing SBM, the insoluble, complex substrate. Sugar residues produced from the hydrolysis of LBG illustrated the effective breakdown of galactomannan to mannobiose (M2), mannotriose (M3), mannotetrose (M4), and mannohexose (M6). SBM-produced sugars analysed via TLC and HPLC indicated that the MOS residues were most probably glucose, galactose, and galactomannans (GM2 and GM3). The SBM-produced sugars were then evaluated for their prebiotic effect, illustrating their successful utilisation as a carbon source by probiotic bacteria; Streptococcus thermophilus, Bacillus subtilis and Lactobacillus bulgaricus. Evaluation of the antimicrobial activities of the SBM-produced sugars digested by probiotics suggested that their metabolites had the potential to be used as an antibiotic alternative. This study therefore illustrated that an endo-1,4-β-mannanase derived from Aspergillus niger could be immobilised successfully, for use in a recyclable reaction to produce MOS products. This study also described the successful use of SBM-sugars as a prebiotic, indicating a successful alternative to antibiotic growth promoters (AGP) by illustrating their positive effect on inhibiting growth of pathogenic bacterial species. , Thesis (MSc) -- Faculty of Science, Biochemistry, Microbiology & Bioinformatics, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Anderson, Amy Sage
- Date: 2024-10-11
- Subjects: Aspergillus niger , Soybean meal , Mannosidases , Oligosaccharides , Immobilized microorganisms
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463897 , vital:76455
- Description: This study investigated the potential for antibiotic alternatives in the form of prebiotics produced from the enzymatic breakdown of soybean meal (SBM). This study first investigated the immobilisation of an endo-1,4-β-mannanase derived from Aspergillus niger on glutaraldehyde-activated chitosan nanoparticles (CTS) and glutaraldehyde-activated chitosan-coated magnetic Fe3O4 nanoparticles (MAGS-CTS) - which could be effectively used to hydrolyse the galactomannan contained in SBM in a recyclable manner. The mannooligosaccharides (MOS) produced from the enzymatic digestion of SBM were then analysed for their prebiotic and antimicrobial capabilities to determine whether the strategy employed was capable of promoting and inhibiting probiotic and pathogenic growth, respectively. An Aspergillus niger endo-1,4-β-mannanase, Man26A, was confirmed by FTIR (Fourier-transform infrared spectroscopy) and XRD (X-ray powder diffraction) to be immobilised onto CTS and MAGS-CTS by covalent bonding. The immobilisation (%) and activity yields (%) were 81.14% and 35.45%, and 55.75% and 21.17%, respectively. The biochemical properties (pH and temperature optima, and temperature stability) of both the free CTS and MAGS-CTS immobilised Man26A enzymes were evaluated, with the pH optima shifting to a lower pH range after immobilisation (pH 2.0 – 3.0 vs. 5.0), while the temperature optima and stabilities remaining unchanged (at 60°C). CTS and free enzymes exhibited identical thermal stabilities, maintaining 100% activity for the first 6 hours at 55°C, while MAGS-CTS showed an immediate drop in relative activity after the first 30 minutes of incubation. Recyclability analysis revealed that CTS could be effectively reused for six reaction cycles, while the MAGS-CTS immobilised enzyme could only be used once. Both enzymes could be efficiently stored at 4ºC, showing a relative residual activity of 73% after 120 hours of storage. Substrate kinetic analysis showed that the free enzyme had the highest catalytic capabilities in hydrolysing locust bean gum (LBG), with the CTS immobilised enzyme was the most efficient in hydrolysing SBM, the insoluble, complex substrate. Sugar residues produced from the hydrolysis of LBG illustrated the effective breakdown of galactomannan to mannobiose (M2), mannotriose (M3), mannotetrose (M4), and mannohexose (M6). SBM-produced sugars analysed via TLC and HPLC indicated that the MOS residues were most probably glucose, galactose, and galactomannans (GM2 and GM3). The SBM-produced sugars were then evaluated for their prebiotic effect, illustrating their successful utilisation as a carbon source by probiotic bacteria; Streptococcus thermophilus, Bacillus subtilis and Lactobacillus bulgaricus. Evaluation of the antimicrobial activities of the SBM-produced sugars digested by probiotics suggested that their metabolites had the potential to be used as an antibiotic alternative. This study therefore illustrated that an endo-1,4-β-mannanase derived from Aspergillus niger could be immobilised successfully, for use in a recyclable reaction to produce MOS products. This study also described the successful use of SBM-sugars as a prebiotic, indicating a successful alternative to antibiotic growth promoters (AGP) by illustrating their positive effect on inhibiting growth of pathogenic bacterial species. , Thesis (MSc) -- Faculty of Science, Biochemistry, Microbiology & Bioinformatics, 2024
- Full Text:
- Date Issued: 2024-10-11
Analyzing Microsporidia sp. MB from sequence to biology: comprehensive exploration of the genome, protein structures, and functions through extensive bioinformatics analysis
- Authors: Ang'ang'o, Lilian Mbaisi
- Date: 2024-10-11
- Subjects: Microsporidia , Whole genome sequencing , Proteins Structure , Symbiont , Malaria Prevention , Vector control
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466480 , vital:76734 , DOI https://doi.org/10.21504/10962/466480
- Description: Microsporidia are spore-forming intracellular organisms classified as the earliest divergent group within the Fungi kingdom. Microsporidia have been found widely affecting different hosts, including both vertebrates and invertebrates. The pathogenicity of microsporidia depends on their species and the host species they infect. Due to their obligate intracellular nature, microsporidia have extensively evolved. This is illustrated by their highly variable genome sizes and gene content. Being minimalist eukaryotes, the microsporidia genome is often associated with extreme gene reduction and compaction. However, these interesting microorganisms retain particular genes that help them acquire specific host nutrients, thereby relying heavily on their host for survival and proliferation. The mode of sexual reproduction of microsporidia has not been well-studied. Harnessing microsporidia in the laboratory is often a challenge, however, the advances in computational tools have made it cheaper and quicker to accurately predict and annotate these organisms to understand their mechanism of infection. Understanding the protein structure and function of these unique organisms is the baseline for providing insights into their biology and survival in their respective hosts. Microsporidia genomes contain a large proportion of hypothetical proteins of which their functions are not described. Vittaforma corneae ATCC 50505 was used as a model to highlight the functions and structure of these otherwise unknown proteins. A systematic annotation pipeline employing exhaustive computational tools was devised to carefully annotate the hypothetical proteins of V. corneae, aiming to characterize their structure and function.The genome of the novel microsporidian, Microsporidia sp. MB, a Plasmodium-transmission-blocking symbiont isolated from Anopheles mosquitoes in Sub-Saharan Africa, was sequenced, assembled, and annotated. The genome was found to contain over 2000 putative genes spanning its 5.9 Mb size and contained minimal repeats. Comparative phylogenomic analysis of Microsporidia sp. MB grouped this symbiont within the Enterocytozoonida (clade IV) microsporidia, clustering with its closest relative – V. corneae. Using robust computational techniques, prediction and characterization of the putative proteins of Microsporidia sp. MB was conducted. The decay of several proteins in the glycolytic pathway is one unique characteristic associated with microsporidia. The proteins retained or lost often vary across the microsporidian taxon. This study highlights the retention of most of the proteins involved in the glycolytic pathway in Microsporidia sp. MB. The available genome dataset of Microsporidia sp. MB was further used to infer its mode of sexual reproduction. The symbiont appears to have several meiotic-related gene orthologs, suggesting that it is capable of sexual reproduction. These findings describe the basic biology of Microsporidia sp. MB and provide a basis for future Next-Generation Sequencing, RNA sequencing experiments ultimately informing the application of this microorganism as a biological malaria control tool. , Thesis (PhD) -- Faculty of Science, Biochemistry, Microbiology and Bioinformatics, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Ang'ang'o, Lilian Mbaisi
- Date: 2024-10-11
- Subjects: Microsporidia , Whole genome sequencing , Proteins Structure , Symbiont , Malaria Prevention , Vector control
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466480 , vital:76734 , DOI https://doi.org/10.21504/10962/466480
- Description: Microsporidia are spore-forming intracellular organisms classified as the earliest divergent group within the Fungi kingdom. Microsporidia have been found widely affecting different hosts, including both vertebrates and invertebrates. The pathogenicity of microsporidia depends on their species and the host species they infect. Due to their obligate intracellular nature, microsporidia have extensively evolved. This is illustrated by their highly variable genome sizes and gene content. Being minimalist eukaryotes, the microsporidia genome is often associated with extreme gene reduction and compaction. However, these interesting microorganisms retain particular genes that help them acquire specific host nutrients, thereby relying heavily on their host for survival and proliferation. The mode of sexual reproduction of microsporidia has not been well-studied. Harnessing microsporidia in the laboratory is often a challenge, however, the advances in computational tools have made it cheaper and quicker to accurately predict and annotate these organisms to understand their mechanism of infection. Understanding the protein structure and function of these unique organisms is the baseline for providing insights into their biology and survival in their respective hosts. Microsporidia genomes contain a large proportion of hypothetical proteins of which their functions are not described. Vittaforma corneae ATCC 50505 was used as a model to highlight the functions and structure of these otherwise unknown proteins. A systematic annotation pipeline employing exhaustive computational tools was devised to carefully annotate the hypothetical proteins of V. corneae, aiming to characterize their structure and function.The genome of the novel microsporidian, Microsporidia sp. MB, a Plasmodium-transmission-blocking symbiont isolated from Anopheles mosquitoes in Sub-Saharan Africa, was sequenced, assembled, and annotated. The genome was found to contain over 2000 putative genes spanning its 5.9 Mb size and contained minimal repeats. Comparative phylogenomic analysis of Microsporidia sp. MB grouped this symbiont within the Enterocytozoonida (clade IV) microsporidia, clustering with its closest relative – V. corneae. Using robust computational techniques, prediction and characterization of the putative proteins of Microsporidia sp. MB was conducted. The decay of several proteins in the glycolytic pathway is one unique characteristic associated with microsporidia. The proteins retained or lost often vary across the microsporidian taxon. This study highlights the retention of most of the proteins involved in the glycolytic pathway in Microsporidia sp. MB. The available genome dataset of Microsporidia sp. MB was further used to infer its mode of sexual reproduction. The symbiont appears to have several meiotic-related gene orthologs, suggesting that it is capable of sexual reproduction. These findings describe the basic biology of Microsporidia sp. MB and provide a basis for future Next-Generation Sequencing, RNA sequencing experiments ultimately informing the application of this microorganism as a biological malaria control tool. , Thesis (PhD) -- Faculty of Science, Biochemistry, Microbiology and Bioinformatics, 2024
- Full Text:
- Date Issued: 2024-10-11
Promoting Grade 9 mathematics teachers’ TPACK development through planning algebra lessons that integrate technology in Oshakati education circuit
- Authors: Angula, Mechtilde
- Date: 2024-10-11
- Subjects: Algebra Study and teaching (Secondary) Namibia Oshakati , Technological Pedagogical Content Knowledge , Educational technology , Education Social aspects Namibia , Culturally relevant pedagogy Namibia
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463669 , vital:76430
- Description: The revised curriculum in Namibia highlights the integration of digital tools to help learners understand mathematics better. For this purpose, teachers need to possess Technological Pedagogical Content Knowledge (TPACK) to utilize technology effectively. However, using technology by itself does not guarantee better learning rather, it requires an understanding of how to integrate technology in teaching mathematics. Therefore, this case study explored Grade 9 mathematics teachers’ TPACK development through planning algebra lessons that integrate technology. An interpretive paradigm, supported by a pragmatic paradigm, underpins the study, and a qualitative case study approach was employed. The study purposively engaged ten Grade 9 mathematics teachers from four schools in Namibia. Demographic questionnaires, Semi-structured interviews, Reflective journals, notes from discussions, focus group interviews and document analysis were used to gain teachers’ insights on TPACK development. The study was guided by two educational theories: Bernstein's Sociology of Education (1971) and Bloom's Taxonomy of the Cognitive Domain (1956). Also, Mishra and Koehler’s TPACK framework (2009) was used to analyze the data. The findings showed that mathematics teachers had a positive view of technology integration in mathematics lessons and TPACK development through technology-integrated lesson planning, but they lacked the knowledge for planning lessons that integrate technology. Taking part in the intervention improved the selected mathematics teachers' understanding of TPACK, making them more confident about using technology in their teaching. The study also found different strategies to help teachers incorporate technology into their lessons, along with having a strong grasp of the subject and effective teaching methods. Based on these findings, it is suggested that in-service mathematics teachers take part in interventions focused on integrating technology into lesson planning. These interventions should demonstrate how technology can improve mathematics education and how it fits with both content and teaching methods. It is also recommended that these interventions emphasize the importance of Bloom's Taxonomy in using technology for mathematics education. The study concludes by suggesting further research on how planned lessons can be implemented in actual mathematics classrooms. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Angula, Mechtilde
- Date: 2024-10-11
- Subjects: Algebra Study and teaching (Secondary) Namibia Oshakati , Technological Pedagogical Content Knowledge , Educational technology , Education Social aspects Namibia , Culturally relevant pedagogy Namibia
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463669 , vital:76430
- Description: The revised curriculum in Namibia highlights the integration of digital tools to help learners understand mathematics better. For this purpose, teachers need to possess Technological Pedagogical Content Knowledge (TPACK) to utilize technology effectively. However, using technology by itself does not guarantee better learning rather, it requires an understanding of how to integrate technology in teaching mathematics. Therefore, this case study explored Grade 9 mathematics teachers’ TPACK development through planning algebra lessons that integrate technology. An interpretive paradigm, supported by a pragmatic paradigm, underpins the study, and a qualitative case study approach was employed. The study purposively engaged ten Grade 9 mathematics teachers from four schools in Namibia. Demographic questionnaires, Semi-structured interviews, Reflective journals, notes from discussions, focus group interviews and document analysis were used to gain teachers’ insights on TPACK development. The study was guided by two educational theories: Bernstein's Sociology of Education (1971) and Bloom's Taxonomy of the Cognitive Domain (1956). Also, Mishra and Koehler’s TPACK framework (2009) was used to analyze the data. The findings showed that mathematics teachers had a positive view of technology integration in mathematics lessons and TPACK development through technology-integrated lesson planning, but they lacked the knowledge for planning lessons that integrate technology. Taking part in the intervention improved the selected mathematics teachers' understanding of TPACK, making them more confident about using technology in their teaching. The study also found different strategies to help teachers incorporate technology into their lessons, along with having a strong grasp of the subject and effective teaching methods. Based on these findings, it is suggested that in-service mathematics teachers take part in interventions focused on integrating technology into lesson planning. These interventions should demonstrate how technology can improve mathematics education and how it fits with both content and teaching methods. It is also recommended that these interventions emphasize the importance of Bloom's Taxonomy in using technology for mathematics education. The study concludes by suggesting further research on how planned lessons can be implemented in actual mathematics classrooms. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2024
- Full Text:
- Date Issued: 2024-10-11
Enhancing licence plate recognition for a robust vehicle re-identification system
- Authors: Boby, Alden Zachary
- Date: 2024-10-11
- Subjects: Automobile theft South Africa , Deep learning (Machine learning) , Object detection , YOLOv7 , YOLO , Pattern recognition systems , Image processing Digital techniques , Automobile license plates
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464322 , vital:76501
- Description: Vehicle security is a growing concern for citizens of South Africa. Law enforcement relies on reports and security camera footage for vehicle identification but struggles to match the increasing number of carjacking incidents and low vehicle recovery rates. Security camera footage offers an accessible means to identify stolen vehicles, yet it often poses hurdles like anamorphic plates and low resolution. Furthermore, depending on human operators proves inefficient, requiring faster processes to improve vehicle recovery rates and trust in law enforcement. The integration of deep learning has revolutionised object detection algorithms, increasing the popularity of vehicle tracking for security purposes. This thesis investigates advanced deep-learning methods for a comprehensive vehicle search and re-identification system. It enhances YOLOv7’s algorithmic capabilities and employs preprocessing techniques like super-resolution and perspective correction via the Improved Warped Planar Object Detection network for more effective licence plate optical character recognition. Key contributions include a specifically annotated dataset for training object detection models, an optical character recognition model based on YOLOv7, and a method for identifying vehicles in unrestricted data. The system detected rectangular and square licence plates without prior shape knowledge, achieving a 98.7% character recognition rate compared to 95.31% in related work. Moreover, it outperformed traditional optical character recognition by 28.25% and deep-learning EasyOCR by 14.18%. Its potential applications in law enforcement, traffic management, and parking systems can improve surveillance and security through automation. , Thesis (MSc) -- Faculty of Science, Computer Science, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Boby, Alden Zachary
- Date: 2024-10-11
- Subjects: Automobile theft South Africa , Deep learning (Machine learning) , Object detection , YOLOv7 , YOLO , Pattern recognition systems , Image processing Digital techniques , Automobile license plates
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464322 , vital:76501
- Description: Vehicle security is a growing concern for citizens of South Africa. Law enforcement relies on reports and security camera footage for vehicle identification but struggles to match the increasing number of carjacking incidents and low vehicle recovery rates. Security camera footage offers an accessible means to identify stolen vehicles, yet it often poses hurdles like anamorphic plates and low resolution. Furthermore, depending on human operators proves inefficient, requiring faster processes to improve vehicle recovery rates and trust in law enforcement. The integration of deep learning has revolutionised object detection algorithms, increasing the popularity of vehicle tracking for security purposes. This thesis investigates advanced deep-learning methods for a comprehensive vehicle search and re-identification system. It enhances YOLOv7’s algorithmic capabilities and employs preprocessing techniques like super-resolution and perspective correction via the Improved Warped Planar Object Detection network for more effective licence plate optical character recognition. Key contributions include a specifically annotated dataset for training object detection models, an optical character recognition model based on YOLOv7, and a method for identifying vehicles in unrestricted data. The system detected rectangular and square licence plates without prior shape knowledge, achieving a 98.7% character recognition rate compared to 95.31% in related work. Moreover, it outperformed traditional optical character recognition by 28.25% and deep-learning EasyOCR by 14.18%. Its potential applications in law enforcement, traffic management, and parking systems can improve surveillance and security through automation. , Thesis (MSc) -- Faculty of Science, Computer Science, 2024
- Full Text:
- Date Issued: 2024-10-11
The effect of an alkyl chain and β-diketonato-metal moiety on the photochromic behaviour of azobenzene compounds as materials for solar thermal fuels
- Authors: Bokhe, Witness Londi
- Date: 2024-10-11
- Subjects: Photochemistry , Isomerization , Solar thermal energy , Solar thermal fuel , Liquid crystals , Optical materials
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464510 , vital:76517
- Description: Scientists have been studying the development of renewable energy technologies in detail to create a sustainable energy supply. Among many new advanced material classes being researched recently are photo functional and photo responsive materials. These classes include azobenzene derivatives which are characterized by azo linkage (N=N) sandwiched by two phenyl rings. The trans-to-cis isomerization of azobenzene is a highly efficient and reversible process, making it an ideal candidate for solar thermal energy storage. This research investigates the impact of alkyl chain modifications and the incorporation of a β-diketonato-copper(II) complex on azobenzene derivatives, aiming to optimize their performance as efficient components in solar thermal fuel cells (STFs). The study focuses on a comprehensive analysis of these materials' ability to capture, convert, store, and release solar energy for enhanced sustainability in renewable energy applications. Experimental methodologies include synthesis of azobenzene derivatives with varying alkyl chain length, n (where n =8 & 10) and coordination of these compounds with a β-diketonato-copper(II) complex. Standard analytical techniques such as Nuclear Magnetic Resonance (1H and 13C NMR), Fourier Transform Infrared Spectroscopy (FTIR) and Ultraviolet/visible spectroscopy (UV/vis) were employed for chemical analysis of the synthesized material. Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), and Polarised Optical Microscope (POM) were used to study the thermal properties and morphology. The photostationery states were determined using NMR spectroscopy and the kinetic parameters of the cis-to-trans relaxation process determined by a UV spectroscopy study. The cis-to-trans isomerisation had a longer half-life than the trans-to-cis isomerisation. The band gap of the isomers is within the range of semiconducting inorganic materials. DSC and POM thermograms showed that the compounds are liquid crystalline. Finally, the study reports that the synthesised azobenzene derivatives show potential as material for solar thermal fuel cells because of their photo-isomerization ability. Furthermore, the synthesised compounds contribute to the advancement of sustainable and efficient solar energy utilization technologies, addressing the growing demand for clean energy solutions in the face of global environmental challenges. Because solar energy may be stored and used without causing direct emissions or pollution, they are considered clean energy. If solar thermal fuels fulfil sustainability standards, they may qualify as green energy. This entails minimising adverse effects on the environment, using non-toxic chemicals and procedures. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Bokhe, Witness Londi
- Date: 2024-10-11
- Subjects: Photochemistry , Isomerization , Solar thermal energy , Solar thermal fuel , Liquid crystals , Optical materials
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464510 , vital:76517
- Description: Scientists have been studying the development of renewable energy technologies in detail to create a sustainable energy supply. Among many new advanced material classes being researched recently are photo functional and photo responsive materials. These classes include azobenzene derivatives which are characterized by azo linkage (N=N) sandwiched by two phenyl rings. The trans-to-cis isomerization of azobenzene is a highly efficient and reversible process, making it an ideal candidate for solar thermal energy storage. This research investigates the impact of alkyl chain modifications and the incorporation of a β-diketonato-copper(II) complex on azobenzene derivatives, aiming to optimize their performance as efficient components in solar thermal fuel cells (STFs). The study focuses on a comprehensive analysis of these materials' ability to capture, convert, store, and release solar energy for enhanced sustainability in renewable energy applications. Experimental methodologies include synthesis of azobenzene derivatives with varying alkyl chain length, n (where n =8 & 10) and coordination of these compounds with a β-diketonato-copper(II) complex. Standard analytical techniques such as Nuclear Magnetic Resonance (1H and 13C NMR), Fourier Transform Infrared Spectroscopy (FTIR) and Ultraviolet/visible spectroscopy (UV/vis) were employed for chemical analysis of the synthesized material. Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), and Polarised Optical Microscope (POM) were used to study the thermal properties and morphology. The photostationery states were determined using NMR spectroscopy and the kinetic parameters of the cis-to-trans relaxation process determined by a UV spectroscopy study. The cis-to-trans isomerisation had a longer half-life than the trans-to-cis isomerisation. The band gap of the isomers is within the range of semiconducting inorganic materials. DSC and POM thermograms showed that the compounds are liquid crystalline. Finally, the study reports that the synthesised azobenzene derivatives show potential as material for solar thermal fuel cells because of their photo-isomerization ability. Furthermore, the synthesised compounds contribute to the advancement of sustainable and efficient solar energy utilization technologies, addressing the growing demand for clean energy solutions in the face of global environmental challenges. Because solar energy may be stored and used without causing direct emissions or pollution, they are considered clean energy. If solar thermal fuels fulfil sustainability standards, they may qualify as green energy. This entails minimising adverse effects on the environment, using non-toxic chemicals and procedures. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Date Issued: 2024-10-11
Assessing the impacts of Lantana camara and opportunities for ecological restoration after its removal: does clearing facilitate both soil and native vegetation recovery?
- Authors: Bolosha, Uviwe
- Date: 2024-10-11
- Subjects: Lantana camara , Restoration and conservation , Restoration ecology , Invasive plants , Physicochemical process , Soil seed banks , Invasion driver
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466524 , vital:76738 , DOI https://doi.org/10.21504/10962/466524
- Description: Invasive alien plants (IAPs) are one of the major contributing factors to biodiversity loss, and Lantana camara is among the top ten alien invaders worldwide. Lantana camara threatens native biodiversity and human health, prevents natural succession, and has an economic and environmental impact globally. With current climate change and future predictions, these IAPs are anticipated to continue posing huge threats to ecosystem composition, structure, and function. Even though L. camara is a widespread IAP, there is still limited knowledge in South Africa on how it influences soil physicochemical properties at the species level, vegetation communities, and soil seed banks at the community level following its invasion. There is also minimal knowledge on the management and control (i.e., clearing for restoration purposes) of L. camara in South Africa, especially in the Eastern Cape province of South Africa. To address the knowledge gap, this thesis was structured into three main aspects: understanding L. camara invasion mechanisms, evaluating invasion impacts on both the aboveground and belowground communities, and invasion management. The main objectives of this thesis were (i) to examine how L. camara invasion (at a species level) affected soil physicochemical properties across different seasons, (ii) to assess how L. camara influences natural vegetation (at a community level), (iii) to examine the effects of L. camara invasion (at the community level) on belowground soil seed banks and also assess the availability of pioneer native species and IAPs in the soil seed banks, and (iv) to evaluate soil and vegetation responses following L. camara clearing in comparison to invaded and uninvaded conditions. To answer these objectives, different studies were carried out in the Eastern Cape province, South Africa, on various farms within the Albany Thicket Biome. The results (Chapter 3) show that L. camara alters and modifies some soil physical properties, such as soil infiltration rate, repellency, and soil penetration resistance, in the communities it invades. A significant decrease in soil penetration under the L. camara canopy was observed compared to soils from the edge and out position. Moreover, significantly faster infiltration rates were observed in the canopy and edge positions than in the out position. The study also observed that these modifications in soil physical properties vary depending on the season. A seasonal comparison in soil penetration showed that soil was more compact in the dry season than the wet season, and significantly faster infiltration rates were observed in summer than in the other seasons. The soil collected under the invaded sampling positions was mostly wettable (80–100%), and not strongly, severely, or extremely repellent across all the seasons. The changes in soil properties caused by L. camara could create favourable conditions for its growth and invasion. Seasonal changes in soil properties also highlight how environmental conditions, especially temperature and rainfall patterns, can affect soil physical properties. The findings in Chapter 4 observed both the negative and positive impacts of L. camara, where the species did not have negative effects on species richness, diversity, or cover of some native species growth forms (i.e., graminoids and forbs). For all species, both species richness and Shannon-Wiener (H’) were significantly higher in the L. camara invaded condition compared to the uninvaded condition. The Simpson’s (J’) and Pielou’s evenness (D’) indices, however, showed no differences between the invasion conditions. Furthermore, the effects of L. camara on vegetation cover were growth form-dependent, with differences being noted for trees and shrubs but not for graminoids and forbs. Changes in vegetation structure and composition were also noted where L. camara created favourable conditions for some species to co-occur with it, meaning that its known trait of changing soil physicochemical properties could benefit some species. Generally, the results of this study showed that the effects of L. camara on vegetation are varied and do not have a predictable pattern, so they should not be generalised. The findings (Chapter 5) also indicate that the L. camara invasion had a negative impact on seedling abundance and composition but not species diversity and richness. This is evident through the decrease in seedling abundance of forbs and graminoids in the L. camara invaded condition. Lantana camara also acted as a refuge for some plant species, mostly native forbs and grasses, including Aptenia cordifolia, Chamaesyce prostrata, Oxalis spp., and Setaria spp., as well as alien forbs such as Bidens pilosa, Plantago lanceolata, and Taraxacum officinale, suggesting L. camara does not entirely eliminate less competitive plant species but can co-exist with them. Lantana camara also displaced some native species, and this could be associated with their displacement in the standing vegetation. Moreover, the species also displaced the seed banks of some alien species, thus showing its competitive ability. Overall, L. camara invasion negatively influenced soil seed bank seedling abundance and composition of some species, but not diversity and richness. The results in Chapter 6 indicated that clearing L. camara is an effective method for reducing its population. However, our findings suggest that clearing alone may not be enough to re-establish these communities with native species. This is because the results of this study showed varied changes in soil properties and native vegetation (species richness, species diversity, percentage cover, and composition) after L. camara clearing. For example, soil moisture and soil penetration resistance showed no significant differences among the invasion conditions; only monthly variations were observed. This is an indication that seasonality influenced these properties. Significantly lower soil infiltration rates were observed in the cleared condition compared to the other conditions and were influenced by the months and the interaction of the clearing conditions and months. The water droplet penetration time showed no significant difference among the clearing conditions over the three months, and all the soil collected from the three clearing conditions was mostly wettable. Soil chemical properties showed that the L. camara invaded and cleared conditions had significantly lower soil pH compared to the uninvaded condition, and an increase in soil pH was observed after clearing L. camara. Vegetation characteristics showed that both the Shannon-Wiener index (H') and the Simpson’s index (D') were lower in the invaded and cleared conditions compared to the uninvaded condition, and significant differences were observed. A slight increase in the H' and D' indices was also observed after clearing L. camara. The mean percentage cover for trees and shrubs was significantly higher in the invaded condition than in the cleared and uninvaded conditions. However, the mean percentage cover of forbs and graminoids was similar among the invaded, cleared, and uninvaded conditions, and no significant differences were observed. When L. camara was cleared, native species recovery was observed and was more notable in the understory species. Overall, some signs of vegetation recovery were observed, although challenges such as secondary invaders and re-invasion by L. camara were noted in the cleared areas. This chapter then concluded that active restoration interventions should be incorporated during restoration to fast-track soil and vegetation recovery. The findings of this thesis will make several significant contributions to the field of biological invasions and provide baseline information that can be used in future studies. These are discussed in the various research chapters. Overall, the thesis concludes that L. camara invasion has varied impacts on native vegetation and soil, and its clearance, should be prioritised to reduce the negative impacts. However, L. camara cleared areas (by WfW in South Africa) require follow-up and monitoring at an early stage to assess vegetation and soil restoration success. In addition, active management measures after L. camara’s removal should be considered for clearing programmes to yield positive ecosystem recovery. , Thesis (PhD) -- Faculty of Science, Environmental Science, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Bolosha, Uviwe
- Date: 2024-10-11
- Subjects: Lantana camara , Restoration and conservation , Restoration ecology , Invasive plants , Physicochemical process , Soil seed banks , Invasion driver
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466524 , vital:76738 , DOI https://doi.org/10.21504/10962/466524
- Description: Invasive alien plants (IAPs) are one of the major contributing factors to biodiversity loss, and Lantana camara is among the top ten alien invaders worldwide. Lantana camara threatens native biodiversity and human health, prevents natural succession, and has an economic and environmental impact globally. With current climate change and future predictions, these IAPs are anticipated to continue posing huge threats to ecosystem composition, structure, and function. Even though L. camara is a widespread IAP, there is still limited knowledge in South Africa on how it influences soil physicochemical properties at the species level, vegetation communities, and soil seed banks at the community level following its invasion. There is also minimal knowledge on the management and control (i.e., clearing for restoration purposes) of L. camara in South Africa, especially in the Eastern Cape province of South Africa. To address the knowledge gap, this thesis was structured into three main aspects: understanding L. camara invasion mechanisms, evaluating invasion impacts on both the aboveground and belowground communities, and invasion management. The main objectives of this thesis were (i) to examine how L. camara invasion (at a species level) affected soil physicochemical properties across different seasons, (ii) to assess how L. camara influences natural vegetation (at a community level), (iii) to examine the effects of L. camara invasion (at the community level) on belowground soil seed banks and also assess the availability of pioneer native species and IAPs in the soil seed banks, and (iv) to evaluate soil and vegetation responses following L. camara clearing in comparison to invaded and uninvaded conditions. To answer these objectives, different studies were carried out in the Eastern Cape province, South Africa, on various farms within the Albany Thicket Biome. The results (Chapter 3) show that L. camara alters and modifies some soil physical properties, such as soil infiltration rate, repellency, and soil penetration resistance, in the communities it invades. A significant decrease in soil penetration under the L. camara canopy was observed compared to soils from the edge and out position. Moreover, significantly faster infiltration rates were observed in the canopy and edge positions than in the out position. The study also observed that these modifications in soil physical properties vary depending on the season. A seasonal comparison in soil penetration showed that soil was more compact in the dry season than the wet season, and significantly faster infiltration rates were observed in summer than in the other seasons. The soil collected under the invaded sampling positions was mostly wettable (80–100%), and not strongly, severely, or extremely repellent across all the seasons. The changes in soil properties caused by L. camara could create favourable conditions for its growth and invasion. Seasonal changes in soil properties also highlight how environmental conditions, especially temperature and rainfall patterns, can affect soil physical properties. The findings in Chapter 4 observed both the negative and positive impacts of L. camara, where the species did not have negative effects on species richness, diversity, or cover of some native species growth forms (i.e., graminoids and forbs). For all species, both species richness and Shannon-Wiener (H’) were significantly higher in the L. camara invaded condition compared to the uninvaded condition. The Simpson’s (J’) and Pielou’s evenness (D’) indices, however, showed no differences between the invasion conditions. Furthermore, the effects of L. camara on vegetation cover were growth form-dependent, with differences being noted for trees and shrubs but not for graminoids and forbs. Changes in vegetation structure and composition were also noted where L. camara created favourable conditions for some species to co-occur with it, meaning that its known trait of changing soil physicochemical properties could benefit some species. Generally, the results of this study showed that the effects of L. camara on vegetation are varied and do not have a predictable pattern, so they should not be generalised. The findings (Chapter 5) also indicate that the L. camara invasion had a negative impact on seedling abundance and composition but not species diversity and richness. This is evident through the decrease in seedling abundance of forbs and graminoids in the L. camara invaded condition. Lantana camara also acted as a refuge for some plant species, mostly native forbs and grasses, including Aptenia cordifolia, Chamaesyce prostrata, Oxalis spp., and Setaria spp., as well as alien forbs such as Bidens pilosa, Plantago lanceolata, and Taraxacum officinale, suggesting L. camara does not entirely eliminate less competitive plant species but can co-exist with them. Lantana camara also displaced some native species, and this could be associated with their displacement in the standing vegetation. Moreover, the species also displaced the seed banks of some alien species, thus showing its competitive ability. Overall, L. camara invasion negatively influenced soil seed bank seedling abundance and composition of some species, but not diversity and richness. The results in Chapter 6 indicated that clearing L. camara is an effective method for reducing its population. However, our findings suggest that clearing alone may not be enough to re-establish these communities with native species. This is because the results of this study showed varied changes in soil properties and native vegetation (species richness, species diversity, percentage cover, and composition) after L. camara clearing. For example, soil moisture and soil penetration resistance showed no significant differences among the invasion conditions; only monthly variations were observed. This is an indication that seasonality influenced these properties. Significantly lower soil infiltration rates were observed in the cleared condition compared to the other conditions and were influenced by the months and the interaction of the clearing conditions and months. The water droplet penetration time showed no significant difference among the clearing conditions over the three months, and all the soil collected from the three clearing conditions was mostly wettable. Soil chemical properties showed that the L. camara invaded and cleared conditions had significantly lower soil pH compared to the uninvaded condition, and an increase in soil pH was observed after clearing L. camara. Vegetation characteristics showed that both the Shannon-Wiener index (H') and the Simpson’s index (D') were lower in the invaded and cleared conditions compared to the uninvaded condition, and significant differences were observed. A slight increase in the H' and D' indices was also observed after clearing L. camara. The mean percentage cover for trees and shrubs was significantly higher in the invaded condition than in the cleared and uninvaded conditions. However, the mean percentage cover of forbs and graminoids was similar among the invaded, cleared, and uninvaded conditions, and no significant differences were observed. When L. camara was cleared, native species recovery was observed and was more notable in the understory species. Overall, some signs of vegetation recovery were observed, although challenges such as secondary invaders and re-invasion by L. camara were noted in the cleared areas. This chapter then concluded that active restoration interventions should be incorporated during restoration to fast-track soil and vegetation recovery. The findings of this thesis will make several significant contributions to the field of biological invasions and provide baseline information that can be used in future studies. These are discussed in the various research chapters. Overall, the thesis concludes that L. camara invasion has varied impacts on native vegetation and soil, and its clearance, should be prioritised to reduce the negative impacts. However, L. camara cleared areas (by WfW in South Africa) require follow-up and monitoring at an early stage to assess vegetation and soil restoration success. In addition, active management measures after L. camara’s removal should be considered for clearing programmes to yield positive ecosystem recovery. , Thesis (PhD) -- Faculty of Science, Environmental Science, 2024
- Full Text:
- Date Issued: 2024-10-11
Research-informed development of comprehensible isiXhosa teaching material: the Department of Basic Education Mental Starters doubling and halving unit
- Authors: Booi, Tabisa
- Date: 2024-10-11
- Subjects: Native language and education South Africa , Mathematics Translating South Africa , South Africa. Department of Basic Education , Translanguaging (Linguistics) , Mathematics Study and teaching (Elementary) South Africa
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463680 , vital:76431
- Description: One of the challenges faced by schools that teach in isiXhosa in the Foundation Phase is the impact of nature of language used in the early-grade mathematics classroom. This is the focus of this research study. Despite numerous programs addressing the poor performance in mathematics, a significant majority of interventions are presented in English, creating barriers for learners and teachers using their native languages. While the Language in Education Policy allows for home language instruction in isiXhosa, the translation of materials often contains distortion in meaning and unfamiliar terms, complicating comprehension for indigenous language learners. Motivated by concerns over low mathematics performance, as highlighted in TIMSS (2019), and my personal experiences in teaching Foundation Phase mathematics in isiXhosa at a rural primary school, this study explores the challenges arising from using translated materials. The use of mediating materials in isiXhosa can be hindered by unfamiliar terms and distortion in meaning. For this reason, I adopted a translanguaging approach, incorporating transliteration between English and isiXhosa, especially in mathematics teaching. Grounded in the pragmatism paradigm, this qualitative design research unfolds in an isiXhosa medium primary school in Makhanda. The investigation centers first on document analysis of the Doubling and Halving unit in the Mental Starters Assessment Programme (MSAP) Teacher Guide (in English and isiXhosa), and then focuses on the teaching of two grade 3 classes, in isiXhosa, using the MSAP Doubling and Halving teaching sequence. Two grade 3 teachers and their principal participate as critical friends. The key research questions are: (1) What are the enablers and constraints that are experienced by the teacher during the mediation of the doubling and halving calculating strategies in isiXhosa?; (2) What are the key terms and phrases (vocabulary) needed to teach doubling and halving in isiXhosa?; (3) What are the perspectives and pedagogical insights of the critical friends on the isiXhosa vocabulary that was developed? The research unfolds in multiple stages, beginning with a document analysis of the MSAP using Toury’s Descriptive Translation Studies. Subsequently, I adapt eight lesson starters for doubling and halving, implementing them across two grade 3 classes in a double action research cycle. Focus group discussions with critical friends, aided by video recordings for stimulated recall, provide valuable insights. Data collected throughout these stages are analyzed through the lens of Vygotsky’s Socio-Cultural theory, contributing to a comprehensive understanding of the challenges and potential solutions in this educational context. , Thesis (MEd) -- Faculty of Education, Primary and Early Childhood Education, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Booi, Tabisa
- Date: 2024-10-11
- Subjects: Native language and education South Africa , Mathematics Translating South Africa , South Africa. Department of Basic Education , Translanguaging (Linguistics) , Mathematics Study and teaching (Elementary) South Africa
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463680 , vital:76431
- Description: One of the challenges faced by schools that teach in isiXhosa in the Foundation Phase is the impact of nature of language used in the early-grade mathematics classroom. This is the focus of this research study. Despite numerous programs addressing the poor performance in mathematics, a significant majority of interventions are presented in English, creating barriers for learners and teachers using their native languages. While the Language in Education Policy allows for home language instruction in isiXhosa, the translation of materials often contains distortion in meaning and unfamiliar terms, complicating comprehension for indigenous language learners. Motivated by concerns over low mathematics performance, as highlighted in TIMSS (2019), and my personal experiences in teaching Foundation Phase mathematics in isiXhosa at a rural primary school, this study explores the challenges arising from using translated materials. The use of mediating materials in isiXhosa can be hindered by unfamiliar terms and distortion in meaning. For this reason, I adopted a translanguaging approach, incorporating transliteration between English and isiXhosa, especially in mathematics teaching. Grounded in the pragmatism paradigm, this qualitative design research unfolds in an isiXhosa medium primary school in Makhanda. The investigation centers first on document analysis of the Doubling and Halving unit in the Mental Starters Assessment Programme (MSAP) Teacher Guide (in English and isiXhosa), and then focuses on the teaching of two grade 3 classes, in isiXhosa, using the MSAP Doubling and Halving teaching sequence. Two grade 3 teachers and their principal participate as critical friends. The key research questions are: (1) What are the enablers and constraints that are experienced by the teacher during the mediation of the doubling and halving calculating strategies in isiXhosa?; (2) What are the key terms and phrases (vocabulary) needed to teach doubling and halving in isiXhosa?; (3) What are the perspectives and pedagogical insights of the critical friends on the isiXhosa vocabulary that was developed? The research unfolds in multiple stages, beginning with a document analysis of the MSAP using Toury’s Descriptive Translation Studies. Subsequently, I adapt eight lesson starters for doubling and halving, implementing them across two grade 3 classes in a double action research cycle. Focus group discussions with critical friends, aided by video recordings for stimulated recall, provide valuable insights. Data collected throughout these stages are analyzed through the lens of Vygotsky’s Socio-Cultural theory, contributing to a comprehensive understanding of the challenges and potential solutions in this educational context. , Thesis (MEd) -- Faculty of Education, Primary and Early Childhood Education, 2024
- Full Text:
- Date Issued: 2024-10-11
The art of adaption: the National Arts Festival’s strategic response to the COVID-19 pandemic
- Authors: Brody, Blake Benjamin
- Date: 2024-10-11
- Subjects: Standard Bank National Arts Festival , Strategic planning , Strategic thinking , Crisis management South Africa , Business model , Stakeholder management , COVID-19 Pandemic, 2020- Influence
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/461863 , vital:76246
- Description: The National Arts Festival (NAF), an annual event held in South Africa, faced a significant challenge in 2020 due to the COVID-19 pandemic. The traditional in-person format of the festival was no longer feasible due to government restrictions. In response, the NAF's CEO, Monica Newton, led her team in a rapid transition to a virtual platform. This decision-making process and the creation of the first virtual NAF (vNAF) occurred within a remarkably short period of 100 days. This teaching case study delves into the academic framework of crisis management, stakeholder theory, strategic thinking, strategic management, and business models, examining their application in the context of the NAF's transformation. To understand the decision-making process and challenges faced by the NAF, a qualitative research design was employed. Data collection involved two face-to-face interviews with Monica Newton, CEO of the NAF, and secondary sources. The teaching case is accompanied by a comprehensive note for educators, offering guidance on its classroom use. The note includes a case synopsis, intended audience, suggested learning outcomes, theoretical connections, teaching strategies, potential discussion questions, evaluation methods, and additional resources. It supports a multi-faceted analysis of the NAF's transformation and encourages vibrant class discussion. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Brody, Blake Benjamin
- Date: 2024-10-11
- Subjects: Standard Bank National Arts Festival , Strategic planning , Strategic thinking , Crisis management South Africa , Business model , Stakeholder management , COVID-19 Pandemic, 2020- Influence
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/461863 , vital:76246
- Description: The National Arts Festival (NAF), an annual event held in South Africa, faced a significant challenge in 2020 due to the COVID-19 pandemic. The traditional in-person format of the festival was no longer feasible due to government restrictions. In response, the NAF's CEO, Monica Newton, led her team in a rapid transition to a virtual platform. This decision-making process and the creation of the first virtual NAF (vNAF) occurred within a remarkably short period of 100 days. This teaching case study delves into the academic framework of crisis management, stakeholder theory, strategic thinking, strategic management, and business models, examining their application in the context of the NAF's transformation. To understand the decision-making process and challenges faced by the NAF, a qualitative research design was employed. Data collection involved two face-to-face interviews with Monica Newton, CEO of the NAF, and secondary sources. The teaching case is accompanied by a comprehensive note for educators, offering guidance on its classroom use. The note includes a case synopsis, intended audience, suggested learning outcomes, theoretical connections, teaching strategies, potential discussion questions, evaluation methods, and additional resources. It supports a multi-faceted analysis of the NAF's transformation and encourages vibrant class discussion. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2024
- Full Text:
- Date Issued: 2024-10-11
Design and fabrication of millifluidic devices for maintenance of tissue cultures under perfusion
- Buthelezi, Khanyisile Thando Fatima
- Authors: Buthelezi, Khanyisile Thando Fatima
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464358 , vital:76504
- Description: Restricted access. Expected release in 2026. , Thesis (MSc) -- Faculty of Science, Biotechnology Innovation Centre, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Buthelezi, Khanyisile Thando Fatima
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464358 , vital:76504
- Description: Restricted access. Expected release in 2026. , Thesis (MSc) -- Faculty of Science, Biotechnology Innovation Centre, 2024
- Full Text:
- Date Issued: 2024-10-11
Macroinvertebrate population dynamics, community composition and diversity patterns of two coastal lakes in northern KwaZulu-Natal, South Africa
- Authors: Campbell, Kaylee Maria
- Date: 2024-10-11
- Subjects: Indicators (Biology) , Lakes South Africa KwaZulu-Natal , Sibayi, Lake (South Africa) , Lake Mzingazi Dam , Biological monitoring South Africa KwaZulu-Natal , Biodiversity , Geospatial data South Africa KwaZulu-Natal , Land use Planning South Africa KwaZulu-Natal
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464406 , vital:76508
- Description: The 2018 South African National Biodiversity Assessment (NBA) identified eight freshwater lakes of national ecological importance and a lack of understanding of their biology. The assessment further called for baseline foundational data for their conservation. Aquatic invertebrates are considered to be reliable and sensitive biological indicators of environmental and water quality changes, and understanding aquatic invertebrate dynamics in these systems will provide a comprehensive understanding of how they can be better protected. The NBA also highlighted a gap in data associated with ecological response to landscape developments and climate change (mainly below average precipitation and increased temperatures) and how this contributes to aquatic resource conservation. This further complicates the modelling of important ecological thresholds and hampers the prediction of possible responses of these ecosystems to environmental changes. This gap informed the aims and rationale of this dissertation; to identify longer-term spatiotemporal trends in aquatic invertebrate communities in Lake Sibaya and Lake Mzingazi and to determine whether the surrounding land use changes could lead to long-term changes in aquatic invertebrate communities of both lakes by comparing recent survey data with historical datasets. In Chapter 2, this dissertation investigated the population dynamics of freshwater shrimp, Caridina africana in Lake Sibaya and Mzingazi and compared the data to that of 1975 study published by Hart (1981). This was done to assess any changes in the C. africana populations due to the considerable changes in land use and weather patterns that have occurred in the last 48 years in and around the systems. Results from Lake Sibaya and Lake Mzingazi were also compared to determine any differences in urban and agricultural stressors presented to C. africana populations. This chapter hypothesised that increases in anthropogenic pollution, invasive species and other habitat modifications at Lake Sibaya and Lake Mzingazi would lead to (1) reductions in shrimp densities and changes in population dynamics when comparing with the 1975 data from Hart (1981). Additionally, it was predicted that (2) Caridina africana abundances found at Lake Mzingazi would be lower than those found at Lake Sibaya (3) due to different water quality variables associated with land use. Results showed that C. africana population densities at Lake Sibaya and lake level recordings had experienced significant decreases since 1975 with densities being significantly lower in 2021. Additional differences seen in 2021 when compared to 1975 were that females were more abundant than males, individuals between the sizes of 3mm and 5mm were most abundant instead of those in the smallest size class (<0.83mm – 1.67mm) and females only dominated size classes above 4mm instead of all size classes above 2.5mm. Populations at Lake Sibaya were negatively correlated with nitrate concentrations in 2021 and populations at Lake Mzingazi were negatively correlated with temperature according to generalised linear models. These results emphasized the importance of pollution mitigation, sustainable water abstraction and the maintenance of natural water temperature ranges in the conservation of lentic C. africana populations. There was also no evidence that urbanisation and agriculture presented different threats to freshwater shrimp populations. In Chapter 3, this dissertation aimed to quantify the littoral aquatic invertebrate diversity and assemblage patterns from Lake Sibaya and Lake Mzingazi to provide comprehensive baseline datasets for these coastal systems. This chapter also aimed to investigate the impacts of landscape developments and habitat change on aquatic invertebrate communities by understanding significant water quality parameters as drivers of community variation. Predictions for Chapter 3 were that increases in agricultural and anthropogenic disturbance and habitat modification will lead to (1) aquatic invertebrate community composition at lakes Sibaya and Mzingazi being structured according to water quality variables that stem from surrounding land-use activities, leading to (2) differing community structures at each lake. Lastly, it was hypothesised that (3) the presence of the invasive snail Tarebia granifera would likely be affecting the aquatic invertebrate diversity and composition of both lakes. According to linear models, aquatic invertebrate abundance at Lake Sibaya was negatively affected by salinity, lake level and phosphate concentration, and positively associated with temperature. Taxa richness and Pielou’s evenness at the lake were negatively associated with conductivity and nitrate concentrations respectively. The aquatic invertebrate community at Lake Sibaya also followed typical seasonal patterns. At Lake Mzingazi, Pielou’s evenness was negatively associated with nitrate and ammonium concentrations and no typical seasonal patterns were evident in the community composition. Communities at Lake Mzingazi also exhibited resilience despite changes in physicochemical parameters, emphasising the difficulty in predicting aquatic community response to habitat modification due to lake-specific community resilience. Tarebia granifera populations at Lake Sibaya were found to negatively affect invertebrate diversity scores according to generalised linear models. Additionally, no individuals of Melanoides tuberculata were found in either system indicating the possibility that these native snails may have been outcompeted by their invasive counterpart. The prevalence of significant stressors associated with habitat disturbance and the unexpected results seen at Lake Mzingazi emphasized the importance of monitoring aquatic invertebrate communities in response to climate change and associated land use developments to adequately understand the long-term threats these changes pose to freshwater ecosystems and biodiversity conservation. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Campbell, Kaylee Maria
- Date: 2024-10-11
- Subjects: Indicators (Biology) , Lakes South Africa KwaZulu-Natal , Sibayi, Lake (South Africa) , Lake Mzingazi Dam , Biological monitoring South Africa KwaZulu-Natal , Biodiversity , Geospatial data South Africa KwaZulu-Natal , Land use Planning South Africa KwaZulu-Natal
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464406 , vital:76508
- Description: The 2018 South African National Biodiversity Assessment (NBA) identified eight freshwater lakes of national ecological importance and a lack of understanding of their biology. The assessment further called for baseline foundational data for their conservation. Aquatic invertebrates are considered to be reliable and sensitive biological indicators of environmental and water quality changes, and understanding aquatic invertebrate dynamics in these systems will provide a comprehensive understanding of how they can be better protected. The NBA also highlighted a gap in data associated with ecological response to landscape developments and climate change (mainly below average precipitation and increased temperatures) and how this contributes to aquatic resource conservation. This further complicates the modelling of important ecological thresholds and hampers the prediction of possible responses of these ecosystems to environmental changes. This gap informed the aims and rationale of this dissertation; to identify longer-term spatiotemporal trends in aquatic invertebrate communities in Lake Sibaya and Lake Mzingazi and to determine whether the surrounding land use changes could lead to long-term changes in aquatic invertebrate communities of both lakes by comparing recent survey data with historical datasets. In Chapter 2, this dissertation investigated the population dynamics of freshwater shrimp, Caridina africana in Lake Sibaya and Mzingazi and compared the data to that of 1975 study published by Hart (1981). This was done to assess any changes in the C. africana populations due to the considerable changes in land use and weather patterns that have occurred in the last 48 years in and around the systems. Results from Lake Sibaya and Lake Mzingazi were also compared to determine any differences in urban and agricultural stressors presented to C. africana populations. This chapter hypothesised that increases in anthropogenic pollution, invasive species and other habitat modifications at Lake Sibaya and Lake Mzingazi would lead to (1) reductions in shrimp densities and changes in population dynamics when comparing with the 1975 data from Hart (1981). Additionally, it was predicted that (2) Caridina africana abundances found at Lake Mzingazi would be lower than those found at Lake Sibaya (3) due to different water quality variables associated with land use. Results showed that C. africana population densities at Lake Sibaya and lake level recordings had experienced significant decreases since 1975 with densities being significantly lower in 2021. Additional differences seen in 2021 when compared to 1975 were that females were more abundant than males, individuals between the sizes of 3mm and 5mm were most abundant instead of those in the smallest size class (<0.83mm – 1.67mm) and females only dominated size classes above 4mm instead of all size classes above 2.5mm. Populations at Lake Sibaya were negatively correlated with nitrate concentrations in 2021 and populations at Lake Mzingazi were negatively correlated with temperature according to generalised linear models. These results emphasized the importance of pollution mitigation, sustainable water abstraction and the maintenance of natural water temperature ranges in the conservation of lentic C. africana populations. There was also no evidence that urbanisation and agriculture presented different threats to freshwater shrimp populations. In Chapter 3, this dissertation aimed to quantify the littoral aquatic invertebrate diversity and assemblage patterns from Lake Sibaya and Lake Mzingazi to provide comprehensive baseline datasets for these coastal systems. This chapter also aimed to investigate the impacts of landscape developments and habitat change on aquatic invertebrate communities by understanding significant water quality parameters as drivers of community variation. Predictions for Chapter 3 were that increases in agricultural and anthropogenic disturbance and habitat modification will lead to (1) aquatic invertebrate community composition at lakes Sibaya and Mzingazi being structured according to water quality variables that stem from surrounding land-use activities, leading to (2) differing community structures at each lake. Lastly, it was hypothesised that (3) the presence of the invasive snail Tarebia granifera would likely be affecting the aquatic invertebrate diversity and composition of both lakes. According to linear models, aquatic invertebrate abundance at Lake Sibaya was negatively affected by salinity, lake level and phosphate concentration, and positively associated with temperature. Taxa richness and Pielou’s evenness at the lake were negatively associated with conductivity and nitrate concentrations respectively. The aquatic invertebrate community at Lake Sibaya also followed typical seasonal patterns. At Lake Mzingazi, Pielou’s evenness was negatively associated with nitrate and ammonium concentrations and no typical seasonal patterns were evident in the community composition. Communities at Lake Mzingazi also exhibited resilience despite changes in physicochemical parameters, emphasising the difficulty in predicting aquatic community response to habitat modification due to lake-specific community resilience. Tarebia granifera populations at Lake Sibaya were found to negatively affect invertebrate diversity scores according to generalised linear models. Additionally, no individuals of Melanoides tuberculata were found in either system indicating the possibility that these native snails may have been outcompeted by their invasive counterpart. The prevalence of significant stressors associated with habitat disturbance and the unexpected results seen at Lake Mzingazi emphasized the importance of monitoring aquatic invertebrate communities in response to climate change and associated land use developments to adequately understand the long-term threats these changes pose to freshwater ecosystems and biodiversity conservation. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-10-11
Combined biological and chemical control of Fusarium associated with Eldana Saccharina walker in South African sugarcane production
- Authors: Cele, Tholakele Gladness
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466502 , vital:76736
- Description: Restricted access. Expected release in 2026. , Thesis (PhD) -- Faculty of Science, Biochemistry, Microbiology and Bioinformatics, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Cele, Tholakele Gladness
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466502 , vital:76736
- Description: Restricted access. Expected release in 2026. , Thesis (PhD) -- Faculty of Science, Biochemistry, Microbiology and Bioinformatics, 2024
- Full Text:
- Date Issued: 2024-10-11
Selective and sensitive electrochemical detection of the Human Epidermal Growth Receptor 2 breast cancer biomarker, using Co (II) phthalocyanine-nanoparticle based platforms
- Centane, Sixolile Sibongiseni
- Authors: Centane, Sixolile Sibongiseni
- Date: 2024-10-11
- Subjects: Electrochemical sensors , HER-2 protein , Breast Cancer , Biochemical markers , Phthalocyanines , Nanoparticles
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466569 , vital:76753 , DOI https://doi.org/10.21504/10962/466570
- Description: Breast cancer is the world’s leading cause of cancer related deaths in women worldwide. The main reason lies in its late detection, mostly in the metastatic stage resulting in poor after-therapy prognosis, despite advances in methods of diagnosis and therapy. The reason for late-stage detection, is because breast cancer like any other cancers is asymptomatic in its early stages. Significant and characterizable features present in the later stages. Furthermore, conventional methods for breast cancer detection are more useful in the identification of the phenotypic features of cancer cells that arise at a later stage of the disease. Another issue with conventional methods where cancer diagnosis is concerned is that they tend to be specialist-dependent, time consuming and costly. Thus, easy, fast and inexpensive detection methods need to be developed urgently. Biomarker-based cancer diagnosis has emerged as one of the most promising strategies for early diagnosis, monitoring disease progression, and subsequent cancer treatment. This thesis focuses on the design and development of novel electrochemical biosensor platforms towards the low cost, efficient, sensitive and simple detection of early-stage breast cancer biomarker, human epidermal growth factor 2 (HER2). The electrochemical method is preferred because of its moderate cost, rapid response, ease of operation, readily quantifiable signal as well as high sensitivity and selectivity with lower detection limits. This thesis reports on two strategies towards signal amplification and sensitive detection of HER2, namely signal based amplification and target-based amplification. The former focuses on electrode or transducer modification techniques for improved signal to noise ratio. In which case; novel nanocomposites of phthalocyanines, graphene quantum dots, gold nanoparticles and cerium oxide nanoparticles are used for electrode modification for signal amplification and biorecognition element immobilization. The biorecognition elements of choice, are an aptamer and antibody known to be specific to the HER2 antigen for an enhanced sensor sensitivity and specificity. The second strategy focuses on increasing the number of detectable targets on the electrode surface towards enhanced sensitivity, precision and sensor accuracy. In which case; the performance of the aptamer and the antibody as recognition elements was explored. Furthermore, the effect of arrangement of these recognition elements on the electrode surface is investigated and reported upon. The strategies covered in this thesis are expected to result in novel biosensor platforms that can detect the HER2 biomarker with high precision, reproducibility, sensitivity and stability; towards low cost and effective early-stage breast cancer diagnostic tools. , Thesis (PhD) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Centane, Sixolile Sibongiseni
- Date: 2024-10-11
- Subjects: Electrochemical sensors , HER-2 protein , Breast Cancer , Biochemical markers , Phthalocyanines , Nanoparticles
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466569 , vital:76753 , DOI https://doi.org/10.21504/10962/466570
- Description: Breast cancer is the world’s leading cause of cancer related deaths in women worldwide. The main reason lies in its late detection, mostly in the metastatic stage resulting in poor after-therapy prognosis, despite advances in methods of diagnosis and therapy. The reason for late-stage detection, is because breast cancer like any other cancers is asymptomatic in its early stages. Significant and characterizable features present in the later stages. Furthermore, conventional methods for breast cancer detection are more useful in the identification of the phenotypic features of cancer cells that arise at a later stage of the disease. Another issue with conventional methods where cancer diagnosis is concerned is that they tend to be specialist-dependent, time consuming and costly. Thus, easy, fast and inexpensive detection methods need to be developed urgently. Biomarker-based cancer diagnosis has emerged as one of the most promising strategies for early diagnosis, monitoring disease progression, and subsequent cancer treatment. This thesis focuses on the design and development of novel electrochemical biosensor platforms towards the low cost, efficient, sensitive and simple detection of early-stage breast cancer biomarker, human epidermal growth factor 2 (HER2). The electrochemical method is preferred because of its moderate cost, rapid response, ease of operation, readily quantifiable signal as well as high sensitivity and selectivity with lower detection limits. This thesis reports on two strategies towards signal amplification and sensitive detection of HER2, namely signal based amplification and target-based amplification. The former focuses on electrode or transducer modification techniques for improved signal to noise ratio. In which case; novel nanocomposites of phthalocyanines, graphene quantum dots, gold nanoparticles and cerium oxide nanoparticles are used for electrode modification for signal amplification and biorecognition element immobilization. The biorecognition elements of choice, are an aptamer and antibody known to be specific to the HER2 antigen for an enhanced sensor sensitivity and specificity. The second strategy focuses on increasing the number of detectable targets on the electrode surface towards enhanced sensitivity, precision and sensor accuracy. In which case; the performance of the aptamer and the antibody as recognition elements was explored. Furthermore, the effect of arrangement of these recognition elements on the electrode surface is investigated and reported upon. The strategies covered in this thesis are expected to result in novel biosensor platforms that can detect the HER2 biomarker with high precision, reproducibility, sensitivity and stability; towards low cost and effective early-stage breast cancer diagnostic tools. , Thesis (PhD) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Date Issued: 2024-10-11
The use of aeration in constructed wetlands and the potential for earthworm and crop production
- Authors: Cesler, Lia
- Date: 2024-10-11
- Subjects: Constructed wetlands South Africa , Breweries South Africa , Water Purification , Land treatment of wastewater , Sewage Purification Aeration
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464440 , vital:76511
- Description: Constructed wetlands (CWs) are used in a variety of industries to treat effluent for safe reuse or discharge. They can however take up large areas of land. Adding oxygen can increase treatment efficiency, as it is vital to many nutrient removal pathways, such as nitrification and aerobic respiration. Increasing efficiency can decrease the cost of treatment and reduce land area needed to operate a CW. The study aimed to find the best method of aerating wetlands treating brewery effluent, the potential production of worms and plants in the system and their effects on water treatment. The first experiment tested a hybrid constructed wetland, using small (1.0 m3) ebb and flow filtration additions to a horizontal subsurface flow constructed wetland against nanobubble aeration in a similar horizontal flow wetland cell. It was not possible to add replicates to the study, but findings prompted further investigation into the hybrid setup. Experiment two focussed on the ebb and flow filters within the hybrid system comparing the presence of plants and worms. The ebb and flow filters increased dissolved oxygen (DO) from an average inflow of 3.89 mg/L to an outflow of 5.70 mg/L and decreased the ammonia content of the effluent from 14.8 mg/L to 11.2 mg/L. Swiss chard (Beta vulgaris) was successfully grown in the system and was found not to affect DO. The addition of both Swiss chard and earthworms (Eisenia fetida) was found to decrease PO43- by 17.69 ± 1.36 %. Experiment 3 compared the previous ebb and flow filters to trickle filters with the addition of celery (Apium graveolens) to both systems to determine which filter treated the effluent more effectively. The ebb and flow filters performed better than the trickle filters, increasing the DO by 37.54 ± 0.06 % compared to 19.22 ± 0.06 %. Celery increased this change in both systems, to 44.16 ± 0.06 % in the ebb and flow filters and 30.96 ± 0.06 % in the trickle filters. The ebb and flow filters were also able to decrease the NH3-N concentration by 36.1 ± 0.2 %. This effluent could sustain plant growth; Swiss chard grew at a rate of 0.04 ± 0.02 g/g/d and celery at 0.2 ± 0.1 g/g/d. Ebb and flow filters are better at aerating brewery effluent and decreasing nutrient load than nanobubble pumps and trickle filters. The addition of ebb and flow filters to the CW treating brewery effluent has the potential to improve nutrient removal and provide an edible crop. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Cesler, Lia
- Date: 2024-10-11
- Subjects: Constructed wetlands South Africa , Breweries South Africa , Water Purification , Land treatment of wastewater , Sewage Purification Aeration
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464440 , vital:76511
- Description: Constructed wetlands (CWs) are used in a variety of industries to treat effluent for safe reuse or discharge. They can however take up large areas of land. Adding oxygen can increase treatment efficiency, as it is vital to many nutrient removal pathways, such as nitrification and aerobic respiration. Increasing efficiency can decrease the cost of treatment and reduce land area needed to operate a CW. The study aimed to find the best method of aerating wetlands treating brewery effluent, the potential production of worms and plants in the system and their effects on water treatment. The first experiment tested a hybrid constructed wetland, using small (1.0 m3) ebb and flow filtration additions to a horizontal subsurface flow constructed wetland against nanobubble aeration in a similar horizontal flow wetland cell. It was not possible to add replicates to the study, but findings prompted further investigation into the hybrid setup. Experiment two focussed on the ebb and flow filters within the hybrid system comparing the presence of plants and worms. The ebb and flow filters increased dissolved oxygen (DO) from an average inflow of 3.89 mg/L to an outflow of 5.70 mg/L and decreased the ammonia content of the effluent from 14.8 mg/L to 11.2 mg/L. Swiss chard (Beta vulgaris) was successfully grown in the system and was found not to affect DO. The addition of both Swiss chard and earthworms (Eisenia fetida) was found to decrease PO43- by 17.69 ± 1.36 %. Experiment 3 compared the previous ebb and flow filters to trickle filters with the addition of celery (Apium graveolens) to both systems to determine which filter treated the effluent more effectively. The ebb and flow filters performed better than the trickle filters, increasing the DO by 37.54 ± 0.06 % compared to 19.22 ± 0.06 %. Celery increased this change in both systems, to 44.16 ± 0.06 % in the ebb and flow filters and 30.96 ± 0.06 % in the trickle filters. The ebb and flow filters were also able to decrease the NH3-N concentration by 36.1 ± 0.2 %. This effluent could sustain plant growth; Swiss chard grew at a rate of 0.04 ± 0.02 g/g/d and celery at 0.2 ± 0.1 g/g/d. Ebb and flow filters are better at aerating brewery effluent and decreasing nutrient load than nanobubble pumps and trickle filters. The addition of ebb and flow filters to the CW treating brewery effluent has the potential to improve nutrient removal and provide an edible crop. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
- Full Text:
- Date Issued: 2024-10-11
IT business consulting competencies to address business intelligence and analytics challenges in South African organisations
- Authors: Chatapura, Ruvimbo Faith
- Date: 2024-10-11
- Subjects: Business enterprises Information technology South Africa , Business intelligence , Business analytics , Business consultants , Dynamic capabilities , Knowledge management
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/462680 , vital:76325
- Description: Background: In today's dynamic environment, the importance and popularity of business intelligence and analytics (BI&A) has increased due to the rise in big data being generated across the globe. BI&A is an essential emerging business competency area and dynamic capability that serves as an enabler for organisations to harvest value from their big data. When implemented correctly, BI&A is a powerful tool that leads to increased competitive advantage. However, organisations in South Africa are facing major challenges when it comes to adopting and harnessing it. As such, it is IT business consultants that South African organisations turn to for acquiring BI&A expertise. Objective: Using the Theory of Dynamic Capabilities as an underpinning lens, the purpose of this study is to investigate the relevant competencies IT business consultants need to address BI&A challenges in South African organisations. This study focuses on developing a BI&A competency framework based on these competencies that IT business consultants can consider when addressing the BI&A challenges in South African organisations. Methods: A qualitative research approach was utilised in this study by making use of an interpretive paradigm, abductive reasoning, qualitative description research strategy, as well as semi-structured interviews and questionnaires as data collection methods to elicit feedback on this study’s BI&A competency framework. Content analysis was conducted to categorise and code the interview data, and descriptive analysis was conducted to rank the competencies in order of relevance. Findings: It was found that the relevant business competencies to consider are business acumen, industry knowledge and strategic conceptual abilities. The relevant technical competencies are categorised into three categories: analytical skills (logical thinking, problem-solving, statistical analysis and what-if analysis), data engineering (data modelling skills, data warehousing, database management, data governance, data interpretation, data stewardship, data visualisation tools and data processing languages) and supplementary skills (project management, consulting skills and artificial intelligence). The relevant values and behavioural competencies to consider are integrity, communication, teamwork, resilience, commitment, creativity, emotional intelligence, humility, behavioural analysis, curiosity, leadership and social intelligence. , Thesis (MCom) -- Faculty of Commerce, Information Systems, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Chatapura, Ruvimbo Faith
- Date: 2024-10-11
- Subjects: Business enterprises Information technology South Africa , Business intelligence , Business analytics , Business consultants , Dynamic capabilities , Knowledge management
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/462680 , vital:76325
- Description: Background: In today's dynamic environment, the importance and popularity of business intelligence and analytics (BI&A) has increased due to the rise in big data being generated across the globe. BI&A is an essential emerging business competency area and dynamic capability that serves as an enabler for organisations to harvest value from their big data. When implemented correctly, BI&A is a powerful tool that leads to increased competitive advantage. However, organisations in South Africa are facing major challenges when it comes to adopting and harnessing it. As such, it is IT business consultants that South African organisations turn to for acquiring BI&A expertise. Objective: Using the Theory of Dynamic Capabilities as an underpinning lens, the purpose of this study is to investigate the relevant competencies IT business consultants need to address BI&A challenges in South African organisations. This study focuses on developing a BI&A competency framework based on these competencies that IT business consultants can consider when addressing the BI&A challenges in South African organisations. Methods: A qualitative research approach was utilised in this study by making use of an interpretive paradigm, abductive reasoning, qualitative description research strategy, as well as semi-structured interviews and questionnaires as data collection methods to elicit feedback on this study’s BI&A competency framework. Content analysis was conducted to categorise and code the interview data, and descriptive analysis was conducted to rank the competencies in order of relevance. Findings: It was found that the relevant business competencies to consider are business acumen, industry knowledge and strategic conceptual abilities. The relevant technical competencies are categorised into three categories: analytical skills (logical thinking, problem-solving, statistical analysis and what-if analysis), data engineering (data modelling skills, data warehousing, database management, data governance, data interpretation, data stewardship, data visualisation tools and data processing languages) and supplementary skills (project management, consulting skills and artificial intelligence). The relevant values and behavioural competencies to consider are integrity, communication, teamwork, resilience, commitment, creativity, emotional intelligence, humility, behavioural analysis, curiosity, leadership and social intelligence. , Thesis (MCom) -- Faculty of Commerce, Information Systems, 2024
- Full Text:
- Date Issued: 2024-10-11
Activist radio and the struggle to empower audiences: a case study of the Zimbabwean history
- Authors: Chaunza, Garikai
- Date: 2024-10-11
- Subjects: Activism Zimbabwe , Radio broadcasting Political aspects Zimbabwe , Authoritarianism Zimbabwe , Democracy Zimbabwe , Zimbabwe Social conditions , Zimbabwe Politics and government
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466907 , vital:76797 , DOI https://doi.org/10.21504/10962/466907
- Description: This study is grounded in my 18-year career in journalism in Zimbabwe. This journey began in January 2006 at the Zimbabwe Broadcasting Corporation (ZBC), where I started as a news reporter. In June 2008, I left ZBC and transitioned to freelance roles, including work at Radio Voice of the People (VOP), which broadcasted from South Africa using Radio Netherlands' transmitters in Madagascar. Simultaneously, I corresponded for The Zimbabwean Newspaper, edited in the UK, printed in Johannesburg, South Africa, and distributed to Zimbabwe, Radio Netherlands, Free Speech Radio News (USA), KPFA Pacifica Foundation Radio (USA), and DW (German). More recently, my work has expanded into the digital domain, contributing to New Zimbabwe, an online newspaper for the Zimbabwean diaspora in the UK, before transitioning to Community Radio Harare. Throughout my 18-year career as a media practitioner and journalist in Zimbabwe, I faced constant state-sanctioned interference, and even physical violence, while executing my responsibilities. Initially, at the Zimbabwe Broadcasting Corporation (ZBC), several colleagues and I, including our news editor, were politically victimised and ultimately fired for covering opposition political players and human rights activists. Later, when I was operating outside state-established media outlets, I experienced a series of threats, intimidation, arrests and detentions by state security. This was also true during my six-year tenure as the chairperson of the Media Institute of Southern Africa's Harare advocacy committee. This experience underscored the importance of studying the history of media activism in this country, focusing on the role that activists have played sustaining the alternative media despite intimidation by the state. I am convinced of the importance documenting their experiences, capturing their contribution to the creation of alternative communication platforms for marginalised audiences. In exploring the literature I discovered that the traditions of activist media, in which I have been involved myself, are rooted in a much older history that can be traced back to pre-independent Zimbabwe. At that time, colonial authorities also restricted media freedoms and employed violence against pro-democracy activities, referred to as nationalists. I decided, for the purpose of this study, to delve into this pre-history of media activism in Zimbabwe, focusing on radio in particular. I wished to gain insight into the way media activists have, over time, sustained their involvement in the traditions of radio practice that can empower marginalised communities. I was conscious that the continued survival of activist radio in this country has often been arduous, with activists facing harassment, arrests, and detentions by authoritarian administrations resisting the opening up of democratic spaces. I wished to trace this history of resistance from its origins in the mid-twentieth century to the time of my own involvement in such radio in the 21st century. In particular, I hoped to identify shared normative foundations as well as shared practices for the implementation of these ideals. Chapter One of the study explores the history of activist radio from the mid-20th century to the present, identifying five distinct phases in Zimbabwe's socio-political history and illustrating how each phase shaped the media landscape. Building on this, Chapter Two establishes a theoretical framework underpinning the values and principles driving media activists to create people-oriented radio projects to empower marginalized communities. Chapter Three delves into the documented history of activist radio within the broader context of media activism in Zimbabwe, engaging with each of the five key moments detailed in Chapter One. Chapter Four outlines the research plan for the empirical fieldwork and discusses its implementation. In Chapter Five, I present interviews with radio activists from the 1970s' nationalist radio and those involved in the pirate radio tradition that re-emerged at the turn of the millennium, sharing their practical experiences. Chapter Six focuses on interviews with community radio advocates, detailing their involvement in radio activism during the first decade of the millennium. Finally, Chapter Seven examines the activities of community radio practitioners, exploring their experiences with unlicensed radio projects and highlighting their creative endeavours. , Thesis (PhD) -- Faculty of Humanities, Journalism and Media Studies, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Chaunza, Garikai
- Date: 2024-10-11
- Subjects: Activism Zimbabwe , Radio broadcasting Political aspects Zimbabwe , Authoritarianism Zimbabwe , Democracy Zimbabwe , Zimbabwe Social conditions , Zimbabwe Politics and government
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466907 , vital:76797 , DOI https://doi.org/10.21504/10962/466907
- Description: This study is grounded in my 18-year career in journalism in Zimbabwe. This journey began in January 2006 at the Zimbabwe Broadcasting Corporation (ZBC), where I started as a news reporter. In June 2008, I left ZBC and transitioned to freelance roles, including work at Radio Voice of the People (VOP), which broadcasted from South Africa using Radio Netherlands' transmitters in Madagascar. Simultaneously, I corresponded for The Zimbabwean Newspaper, edited in the UK, printed in Johannesburg, South Africa, and distributed to Zimbabwe, Radio Netherlands, Free Speech Radio News (USA), KPFA Pacifica Foundation Radio (USA), and DW (German). More recently, my work has expanded into the digital domain, contributing to New Zimbabwe, an online newspaper for the Zimbabwean diaspora in the UK, before transitioning to Community Radio Harare. Throughout my 18-year career as a media practitioner and journalist in Zimbabwe, I faced constant state-sanctioned interference, and even physical violence, while executing my responsibilities. Initially, at the Zimbabwe Broadcasting Corporation (ZBC), several colleagues and I, including our news editor, were politically victimised and ultimately fired for covering opposition political players and human rights activists. Later, when I was operating outside state-established media outlets, I experienced a series of threats, intimidation, arrests and detentions by state security. This was also true during my six-year tenure as the chairperson of the Media Institute of Southern Africa's Harare advocacy committee. This experience underscored the importance of studying the history of media activism in this country, focusing on the role that activists have played sustaining the alternative media despite intimidation by the state. I am convinced of the importance documenting their experiences, capturing their contribution to the creation of alternative communication platforms for marginalised audiences. In exploring the literature I discovered that the traditions of activist media, in which I have been involved myself, are rooted in a much older history that can be traced back to pre-independent Zimbabwe. At that time, colonial authorities also restricted media freedoms and employed violence against pro-democracy activities, referred to as nationalists. I decided, for the purpose of this study, to delve into this pre-history of media activism in Zimbabwe, focusing on radio in particular. I wished to gain insight into the way media activists have, over time, sustained their involvement in the traditions of radio practice that can empower marginalised communities. I was conscious that the continued survival of activist radio in this country has often been arduous, with activists facing harassment, arrests, and detentions by authoritarian administrations resisting the opening up of democratic spaces. I wished to trace this history of resistance from its origins in the mid-twentieth century to the time of my own involvement in such radio in the 21st century. In particular, I hoped to identify shared normative foundations as well as shared practices for the implementation of these ideals. Chapter One of the study explores the history of activist radio from the mid-20th century to the present, identifying five distinct phases in Zimbabwe's socio-political history and illustrating how each phase shaped the media landscape. Building on this, Chapter Two establishes a theoretical framework underpinning the values and principles driving media activists to create people-oriented radio projects to empower marginalized communities. Chapter Three delves into the documented history of activist radio within the broader context of media activism in Zimbabwe, engaging with each of the five key moments detailed in Chapter One. Chapter Four outlines the research plan for the empirical fieldwork and discusses its implementation. In Chapter Five, I present interviews with radio activists from the 1970s' nationalist radio and those involved in the pirate radio tradition that re-emerged at the turn of the millennium, sharing their practical experiences. Chapter Six focuses on interviews with community radio advocates, detailing their involvement in radio activism during the first decade of the millennium. Finally, Chapter Seven examines the activities of community radio practitioners, exploring their experiences with unlicensed radio projects and highlighting their creative endeavours. , Thesis (PhD) -- Faculty of Humanities, Journalism and Media Studies, 2024
- Full Text:
- Date Issued: 2024-10-11