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Effect of adding a probiotic to an aquaponic system on plant and fish growth, water quality, and microbial diversity

  • Authors: Kasozi, Nasser
  • Date: 2022-04-08
  • Subjects: To be added
  • Language: English
  • Type: thesis , text , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/294596 , vital:57236
  • Description: Thesis embargoed. Release date April 2023. , Thesis (PhD) -- Faculty of Science, Ichthyology and Fisheries Science, 2022
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  • Date Issued: 2022-04-08

Hop as an anti-cancer drug target

  • Authors: Vaaltyn, Michaelone Chantelle
  • Date: 2020
  • Subjects: Uncatalogued
  • Language: English
  • Type: thesis , text , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/164704 , vital:41156 , doi:10.21504/10962/164704
  • Description: Thesis (PhD)--Rhodes University, Biochemistry and Microbiology, 2020
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  • Date Issued: 2020

Nature conservation, protected areas and local communities : the Tsitsikamma National Park

  • Authors: Le Fleur, Yvette Adele
  • Date: 2021-04
  • Subjects: National parks and reserves -- South Africa -- Eastern Cape , Protected areas -- Management , Programme of Work on Protected Areas , Human ecology -- South Africa -- Tsitsikamma , Nature conservation -- Citizen participation
  • Language: English
  • Type: thesis , text , Masters , MSocSc
  • Identifier: http://hdl.handle.net/10962/177247 , vital:42803
  • Description: Since the twentieth century, protected areas, usually in the form of nature reserves or national parks, have become increasingly more dominant as an international conservation strategy. An important factor in protected area management is the relationship between protected areas and its surrounding communities. Historically, the fortress conservation model based on the exclusion of human use and occupation prevailed in relation to protected areas. It is known that this approach brought with it many social and environmental injustices to local communities living in or adjacent to parks. However, a shift in conservation thinking occurred towards the end of the twentieth century, where it has increasingly been advocated for a more participatory approach in protected area management. South Africa has signed the international Convention on Biological Diversity that promotes a participatory approach to nature conservation, which is also reflected in the country’s national laws and policies. In relation to the literature and the lens of political ecology, this thesis sets out to assess in what ways and to what extent the participatory approach has been embraced by South Africa’s conservation authorities. As a case study, it looks at the Tsitsikamma National P ark ( incorporated into the larger Garden Route National Park). In order to get insight on h ow the participatory approach plays itself out at the T NP and what the nature of local communities’ relationship with the park is, this study looks at the aspects of (1) local communities’ socio-economic conditions, (2) their relationship with their natural environment, (3) their perception of nature conservation and (4) their perception of tourism. Then, taking all these aspects into account, (5) how local communities, in general, perceive their relationship with the p ark and its authorities. This study looked at the communities of Kurland, Nature’s Valley, Covie and Storms River. It shows in concurrence with other studies, that despite progressive laws and policies that express the intention of the South African state and SANParks to embrace the participatory approach, its implementation o n t he g round is riddled with challenges. , Thesis (MSocSc) -- Faculty of Humanities, Athropology, 2021
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  • Date Issued: 2021-04

An investigation of support services available for black female owners of bed & breakfasts in Makhanda

  • Authors: Mdluli, Lukhona Silubonile
  • Date: 2021-04
  • Subjects: Bed and breakfast accommodations -- South Africa -- Makhanda , Businesspeople, Black -- South Africa -- Makhanda , Business enterprises, Black -- South Africa -- Makhanda , Women-owned business enterprises -- South Africa -- Makhanda , Government aid to small business -- South Africa , Small business -- South Africa -- Makhanda , Racism -- South Africa -- Makhanda , Businesswomen -- South Africa -- Makhanda
  • Language: English
  • Type: thesis , text , Masters , MBA
  • Identifier: http://hdl.handle.net/10962/177181 , vital:42797
  • Description: Over the last 26 years, the South African government has committed to SMME development. To do this, policies and support institutions were put in place which would create a favourable environment for SMME development. This was particularly important as after 1994, when the South African economy was re-integrated into global markets after years of having sanctions imposed against the country as a result of the apartheid system. The tourism industry was identified as one of the key economic drivers which would strengthen the economy and assist in job creation, especially since South Africa would be able to attract international tourists. Further, it created the opportunity for new participants to enter the industry, including black entrepreneurs who previously could not enter the industry as a result of the apartheid laws. The opening up of the country to international markets and the focus on the tourism industry also presented the opportunity for new forms of tourism to be explored including township tourism, which gave rise to the black-owned bed & breakfast sector. Over time, it has become evident that black entrepreneurs in this sector are facing a number of challenges, in spite of the pro-SMME policies and support institutions that are in place. Because this study seeks to investigate the support services available for black female bed & breakfast owners in Makhanda, a qualitative research approach using the interpretative theoretical framework was applied. By using semi-structured interview questions, to establish what challenges do black female bed and breakfast owners face the researcher was able to respond to the following; what participants identify as their needs; and whether they are able to access the support services that are made available by the Government. Results indicated that the majority of entrepreneurs have difficulty accessing funding to develop their businesses. The seasonality of Grahamstown/ Makhanda tourism businesses has its pros and cons for tourism entrepreneurs. Despite efforts by government to transform the tourism industry, black female entrepreneurs in this industry still experience a myriad of challenges, including passive racism. Insufficient institutional support and inaccessible support services for women have made it difficult to manage in this this environment. Thus, a recommendation is put forward for female focused entrepreneurship policy, which is more responsive in terms of a judicial and legal system(s) aimed at addressing women’s particular needs and challenges. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2021
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  • Date Issued: 2021-04

Livelihood implications of a possible Ramsar declaration of the Swartkops estuary, Eastern Cape, South Africa

  • Authors: Vembo, Glen Muchengeti
  • Date: 2020
  • Subjects: Uncatalogued
  • Language: English
  • Type: thesis , text , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/164715 , vital:41157
  • Description: Thesis (MSc)--Rhodes University, Faculty of Science, Environmental Science, 2020
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  • Date Issued: 2020

A Systematic Visualisation Framework for Radio-Imaging Pipelines

  • Authors: Andati, Lexy Acherwa Livoyi
  • Date: 2021-04
  • Subjects: Radio interferometers , Radio astronomy -- Data processing , Radio astronomy -- Data processing -- Software , Jupyter
  • Language: English
  • Type: thesis , text , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/177338 , vital:42812
  • Description: Pipelines for calibration and imaging of radio interferometric data produce many intermediate images and other data products (gain tables, etc.) These often contain valuable information about the quality of the data and the calibration, and can provide the user with valuable insights, if only visualised in the right way. However, the deluge of data that we’re experiencing with modern instruments means that most of these products are never looked at, and only the final images and data products are examined. Furthermore, the variety of imaging algorithms currently available, and the range of their options, means that very different results can be produced from the same set of original data. Proper understanding of this requires a systematic comparison that can be carried out both by individual users locally, and by the community globally. We address both problems by developing a systematic visualisation framework based around Jupyter notebooks, enriched with interactive plots based on the Bokeh and Datashader visualisation libraries. , Thesis (MSc) -- Faculty of Science, Department of Physics and Electronics, 2021
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  • Date Issued: 2021-04

Design of pH Sensitive Electrochemical Sensor for Catecholamine Neurotransmitters Detection and the Screening Off of Ascorbic Acid

  • Authors: Tshenkeng, Keamogetse Tebogo Charlotte
  • Date: 2021-10-29
  • Subjects: Catecholamines , Electrochemical sensors , Neurotransmitters , Vitamin C , Cobalt , Phthalocyanines , Cobalt (II) tetra-(3-carboxyphenoxy) phthalocyanine (CoTCPhOPc)
  • Language: English
  • Type: thesis , text
  • Identifier: http://hdl.handle.net/10962/176921 , vital:42772
  • Description: This study presents the synthesis of cobalt (II) tetra-(3-carboxyphenoxy) phthalocyanine (CoTCPhOPc) through the cyclotetramerization of 4-(3-carboxyphe-noxy)phthalonitrile and its full characterization using Fourier transform infrared (FT-IR) spectroscopy, ultraviolet-visible (UV-vis) spectroscopy, magnetic circular dichroism (MCD) spectroscopy, elemental analysis and mass spectrometry. The CoTCPhOPc was then immobilized onto phenylethylamino (PEA) pre-grafted gold electrode surface, Au-PEA using amide coupling reaction through a reaction with NHS and DCC to obtain Au-PEA-CoTCPhOPc. This yielded pH sensitive thin films due to the terminal carboxylic acid (–COOH) functional groups. Electrochemical and surface characterization was conducted to confirm the modification of the bare Au with PEA thin film (Au-PEA) and amide coupling of CoTCPhOPc (Au-PEA-CoTCPhOPc). The Au-PEA-CoTCPhOPc electrode was shown to possess pH selective properties towards negatively charged [Fe(CN)6]3-/4- and positively charged [Ru(NH3)6]2+/3+ redox probes. Au-PEA-CoTCPhOPc electrode surface enabled the detection of catecholamine neurotransmitters (dopamine, norepinephrine and epinephrine) and the screening off of ascorbic acid by means of pH sensitive functional groups. Bare Au and Au-PEA electrodes exhibited electro-oxidation and electroreduction of catecholamine neuro-transmitters and ascorbic acid at higher potentials compared to Au-PEA-CoTCPhOPc. There was no electro-oxidation or electroreduction of ascorbic acid at Au-PEA-CoTCPhOPc. For Au-PEA-CoTCPhOPc, excellent electrocatalytic oxidation with the limit of detection (LoD) determined using 3σ was found to be 1.32 (0.95), 2.11 (1.78) and 3.08 μM for electro-oxidation and electroreduction (in brackets) of dopamine, norepinephrine and epinephrine respectively. The limit of quantification (LoQ) was determined using 10σ and found to be 4.41 (3.17), 7.02 (5.93) and 10.3 μM electro-oxidation and electroreduction (in brackets) for dopamine, norepinephrine and epinephrine respectively. The Au-PEA-CoTCPhOPc thin film was shown to screen off ascorbic acid as no electrocatalytic oxidation was observed for up to 100.0 μM concentration. , Thesis (MSc) -- Faculty of Science, Department of Chemistry, 2021
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  • Date Issued: 2021-10-29

The Influence of Clientelism on the Informal Sector in Zimbabwe : a Case Study of Glen View 8 Complex, Harare

  • Authors: Tandire, Justin
  • Date: 2021-04
  • Subjects: Patron and client -- Zimbabwe -- Harare , Informal sector (Economics) -- Zimbabwe -- Harare , Informal sector (Economics) -- Political aspects -- Zimbabwe -- Harare , Patronage, Political -- Zimbabwe -- Harare , ZANU-PF (Organization : Zimbabwe) , Zimbabwe -- Social conditions , Glen View Complex 8 (Zimbabwe)
  • Language: English
  • Type: thesis , text , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/177986 , vital:42896 , 10.21504/10962/177986
  • Description: This study focuses on the influence of clientelism in the informal sector of Zimbabwe in Glen View 8 (Complex). The study used the case of Glen view 8 (complex) in Harare Province. The study focused on political dynamics in the informal sector; livelihood strategies employed by informal sector operators; manifestation of “Big Men”, social networks in the informal sector; and different strategies employed by operators to overcome the problems of political manipulation, clientelism and patronage. It employs a qualitative research methodology to enable a nuanced comprehension of the clientelistic relationships that take place in the informal sector of Zimbabwe. Through in-depth interviews, focus group discussions, narratives and in-depth interviews with key informants, the study explored the clientelistic nature of the informal sector. The major findings of the study are that the informal sector in Zimbabwe is influenced by political patronage. It was established that patronage influences the informal sector in Zimbabwe in general and at Glen View Complex 8 in particular. Some of the operators revealed that patronage negatively affects their business as they are sometimes forced to attend political party meetings either at the complex or at ZANU-PF star rallies in town. The operators experience a plethora of problems such as lack of security, poor sanitation, stiff competition, poor infrastructure, lack of insurance and fire outbreaks. It has been revealed that most of the problems experienced at the complex are a result of the politicisation of the informal sector particularly by the ZANU-PF party. Operators at the complex have described the politicisation of the informal sector as a major drawback to their efforts of realising maximum benefits from their work. Therefore, the thrust of this thesis is premised on the de-politicisation of the informal sector as the starting point in the transformation of the activities of the operators. , Thesis (PhD) -- Faculty of Humanities, Sociology, 2021
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  • Date Issued: 2021-04

Observations of cosmic re-ionisation with the Hydrogen Epoch of Reionization Array: simulations of closure phase spectra

  • Authors: Charles, Ntsikelelo
  • Date: 2021-04
  • Subjects: Epoch of reionization , Space interferometry , Astronomy -- Observations , Closure phase spectra
  • Language: English
  • Type: thesis , text , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/174470 , vital:42480
  • Description: The 21 cm transition from neutral Hydrogen promises to be the best observational probe of the Epoch of Reionisation. It has driven the construction of the new generation of low frequency radio interferometric arrays, including the Hydrogen Epoch of Reionization Array (HERA). The main difficulty in measuring the 21 cm signal is the presence of bright foregrounds that require very accurate interferometric calibration. Thyagarajan et al. (2018) proposed the use of closure phase quantities as a means to detect the 21 cm signal, which has the advantage of being independent (to first order) from calibration errors and therefore, bypasses the need for accurate calibration. Closure phases are, however, affected by so-called direction dependent effects, e.g. the fact that the dishes - or antennas - of an interferometric array are not identical to each other and , therefore, yield different antenna primary beam responses. In this thesis, we investigate the impact of direction dependent effects on closure quantities and simulate the impact that primary antenna beams affected by mutual coupling have on the foreground closure phase and its power spectrum i.e. the power spectrum of the bispectrum phase (Thyagarajan et al., 2020). Our simulations show that primary beams affected by mutual coupling lead to an overall leakage of foreground power in the so-called EoR window, i.e. power from smooth-spectrum foregrounds is confined to low k modes. We quantified this effect and found that the leakage is up to ~ 8 orders magnitude higher than the case of an ideal beam at kǁ > 0:5 h Mpc-1. We also found that the foreground leakage is worse when edge antennas are included, as they have a more different primary beam compared to antennas at the centre of the array. The leakage magnitude is worse when bright foregrounds appear in the antenna sidelobes, as expected. Our simulations provide a useful framework to interpret observations and assess which power spectrum region is expected to be most contaminated by foreground power leakage.
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  • Date Issued: 2021-04

An assessment of the wild cyclopia subternata (vleitee) resource

  • Authors: Van der Walt, Wouter
  • Date: 2021-04
  • Subjects: Legumes -- South Africa , Fynbos -- South Africa , Fynbos ecology -- South Africa , Fynbos -- Harvesting -- South Africa , Biodiversity conservation -- South Africa , Traditional ecological knowledge -- South Africa , Wild Cyclopia Subternata (Vleitee) , Honeybush tea industry
  • Language: English
  • Type: thesis , text , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/176874 , vital:42767
  • Description: Cyclopia spp. is used for the production of Honeybush tea, an herbal tea which is used in many cases as a substitute for rooibos tea. The wild harvesting of this fynbos plant still brings in up to 85% of the annual crop and as such needs to be carefully monitored in order to avoid over harvesting and the destruction of biodiversity within the Eastern and Western Cape mountain regions of Southern Africa. Due to the concerns of overharvesting and unsuitable use of the wild resource issues of supply security have been raised. There is a lack of formal knowledge relating to the plant, its harvesting, the industry and its economic potential. This study aimed to amend this scarcity by contributing to the knowledge of C. subternata as a wild harvested plant, the physical environment favoured by C. subternata, sustainable use through harvesting of the wild plant and harvesting methods specific to this honeybush species. The research concludes by presenting a guideline for best harvest practices of the wild C. subternata plant. , Thesis (MSc) -- Faculty of Science, Department of Geography, 2021
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  • Date Issued: 2021-04

Creating shared value through innovating business models: a case study of the Mapela Water Project

  • Authors: Moyo, Bonnie
  • Date: 2021-04
  • Subjects: Business planning -- South Africa , Strategic planning -- South Africa , Sustainable development -- South Africa , Social responsibility of business -- South Africa , Mineral industries -- South Africa , Mapela Water Project , Hourglass Model
  • Language: English
  • Type: thesis , text , Masters , MBA
  • Identifier: http://hdl.handle.net/10962/177135 , vital:42793
  • Description: Shared value creation is a contemporary concept that aims to address the strained relationship between business and society through business models that expand the competitive advantage of business while addressing societal challenges in the business environment. Being a novel concept, studies on how value is created and shared are limited, especially where the unit of analysis is a specific project. This paper investigates how value is created and shared among stakeholders using a water project case study reported as a shared value initiative. The investigation is considered under the Hourglass Model (Ludeke-Freund, Massa, Bocken, Brent and Musango, 2016) as a guiding framework. This sustainable business model is suggested as a business model that creates shared value. The study uses a qualitative research approach to investigate the inputs into the Hourglass Model (Ludeke-Freund et al., 2016) in the form of capitals, briefly considers the business models of specific stakeholders and then analyses the value created, missed and destroyed for each stakeholder through their value creation mechanisms. In the findings, six different capitals are identified from the participating stakeholders, and the value created, destroyed, and missed is discussed in the context of shared value principles. The findings show that capitals are used as inputs into the Hourglass Model and are consumed, created, and regenerated. There is also the realisation from the findings that different stakeholders required different and varying amounts of the six capitals identified. The interconnectedness of the capitals is shown in the study, and the findings show that the context of the environment within which a project operates contributes to the creation of shared value. As with the six capitals, the findings show that multiple stakeholders create shared value confirming stakeholder theory's guiding principles regarding stakeholder salience, which are relevant for creating shared value. Some stakeholders are identified as being more important to creating shared value in the project than others. Trade-offs are then required for value creation from a finite pool of capitals and stakeholders to consider the capitals and stakeholders' long and short-term impacts. Identifying stakeholders and the capitals allowed the researcher to consider the value created, destroyed and missed in the project. This assessment of shared value generated forms part of the findings on business models' outcomes for shared value, summarised for the project. Based on these areas where the outcomes are missing or destroying value, recommendations are made to address these opportunities, and an area of further research is identified. Drawing on these outcomes, developing clusters as per the value creation avenues of shared value would be the most appropriate avenue for this project. The study adds to the shared value body of knowledge by operationalising the Hourglass Model (Ludeke-Freund et al., 2016) and illustrating how the Model can be used to consider shared value creation. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2021
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  • Date Issued: 2021-04

Bioethical analysis of selected biomedical issues in South Africa and other countries

  • Authors: Rusere, Jean
  • Date: 2021-04
  • Subjects: To be added
  • Language: English
  • Type: thesis , text , Masters , MPharm
  • Identifier: http://hdl.handle.net/10962/178530 , vital:42948
  • Description: Access restricted until April 2023. , Thesis (MPharm) -- Faculty of Pharmacy, Pharmacy, 2021
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  • Date Issued: 2021-04

Photodynamic antimicrobial chemotherapy against Staphylococcus aureus and Escherichia coli sensitized using indium (III) cationic porphyrins linked to core-shell magnetic nanoparticles

  • Authors: Makola, Lekgowa Collen
  • Date: 2021-04
  • Subjects: Photochemotherapy , Photosensitizing compounds , Staphylococcus aureus , Escherichia coli , Indium , Porphyrins , Magnetic nanoparticles , Quaternize
  • Language: English
  • Type: thesis , text , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/177225 , vital:42801
  • Description: Photodynamic antimicrobial chemotherapy (PACT) is a well-known antimicrobial therapy technique used against multi-drug resistant pathogens. In this study, the syntheses, characterization, photophysicochemical properties, and the applications of symmetrically and asymmetrically substituted cationic indium (III) porphyrins linked to silver/copper ferrite core-shell (Ag/CuFe2O4) magnetic nanoparticles (MNPs) as potential photosensitizers for PACT are reported. The synthesized complexes include axially modified porphyrins quaternized through an axial ligand. All the asymmetrically substituted porphyrins were linked to the NPs via an ester bond and the symmetrically substituted porphyrins were linked (peripherally and /or axially) via self-assembly (Ag-S and/or Ag-N). The impact of axial modification, peripheral substituents, conjugation to the NPs, the number of positive charges, and the chain length of the alkyl halides quaternizing agents on PACT efficacy and photophysicochemical properties of porphyrins were studied. High singlet oxygen quantum yields and antimicrobial log reductions were observed. Lipophilicity and hydrophilicity of the porphyrins were also studies, where the complexes quaternized with methyl iodide showed relatively high hydrophilicity character. Upon in vitro PACT studies, the quaternized complexes were observed to have 0% viable colony, signifying their effectiveness. Moreover, the highest log reductions of 9.27 were observed against S. aureus and 9.58 were observed against E. coli. The findings from this work delineate that singlet oxygen generation alone is not a distinct factor on the PACT efficacy of the porphyrin complexes, since some of the complexes have practically the same singlet oxygen quantum but different PACT activity. However, other contributing factors including water solubility play a significant role. , Thesis (MSc) -- Faculty of Science, Department of Chemistry, 2021
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  • Date Issued: 2021-04

How selected Grade 7 participants develop conceptual understanding in solving algebraic problems as a result of participating in a screencast intervention

  • Authors: Wienekus, George Renier
  • Date: 2021-04
  • Subjects: Algebra -- Study and teaching -- South Africa , Mathematics -- Study and teaching (Elementary) -- South Africa , Problem solving in children , Algebra -- Ability testing , Algebra -- Computer-assisted instruction
  • Language: English
  • Type: thesis , text , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/176833 , vital:42763
  • Description: This research project is an interventionist case study, oriented in the interpretive paradigm, which aims to investigate how selected Grade 7 participants develop conceptual understanding in solving algebraic problems as a result of participating in screencast interventions. The aim of my screencast intervention programme, which lies at the heart of this study, is to develop practices, inter alia, of how such devices and software may be “used to develop conceptual rather than procedural or decorative knowledge” (Larkin & Calder, 2015:1) in solving linear equations. The planned intervention was delivered in the form of a series of screencasts: these take the form of audio-video lessons with an emphasis on the visual impact, and were recorded using an application called Explain Everything. The screencast interventions were delivered via Google Classroom and included animations supported by such conceptual explanations of early algebra as are relevant to Grade 7 students, and in line with the South African Curriculum and Assessment Policy Statements - Department of Education, 2011. The fundamental components of an early algebraic equation that would be relevant to a Grade 7 student were considered and used to develop an analytic framework. This was based on a taxonomy designed according to four identified “clusters” in order to analyse the workings of the purposefully selected Grade 7 participants who were video recorded and questioned in a talk-aloud interview while they completed a post-intervention pencil-and-paper test. What emerges from this research project is that there is a significant need for specific and concentrated technology-based techniques, such as the interventions undertaken here, and that exploration and development in the field could benefit the delivery of a pedagogy for algebra. The pedagogical methods implemented and studied in the form of screencasts proved to be successful and were well received by the learners particularly in relation to the conceptualisation of “symbol sense” and transformation in early algebra. The structure and design of the screencast interventions were important in supporting the acquisition of these concepts and were demonstrated to be worthwhile tools for an epistemological application in a classroom or teaching context. , Thesis (MEd) -- Rhodes University, Faculty of Education, Education, 2021
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  • Date Issued: 2021-04

Exploring the influences of an intersemiotic complementarity teaching approach on Grade 9 Namibian learners’ sense-making of chemical bonding

  • Authors: Aikanga, Frans Paulus Shintaleleni
  • Date: 2021-04
  • Subjects: Physical sciences -- Study and teaching (Secondary) -- Namibia , Chemical bonds , Semiotics , Cognition in children , Communication in education , Language and education -- Namibia , Visual learning , Verbal learning
  • Language: English
  • Type: thesis , text , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/178281 , vital:42927
  • Description: Anecdotal evidence from my 10 years’ experience teaching Grade 9 Physical Science in Namibian schools revealed learners’ difficulty with making sense of chemical bonding. The Junior Secondary examiners’ reports in recent consecutive years (2014, 2015, 2016 & 2017) also revealed this challenge among Grade 10 learners (Namibia. Ministry of Education, Arts and Culture [MoEAC], 2017). The language of learning and teaching (LoLT) for most school subjects (including Physical Science) in Namibia is English, which is taken as a second language by most learners (Kisting, 2011). The results of the English Language Proficiency test written by all principals and teachers in Namibia show that most are not proficient in this language (Kisting, 2011). This has raised concern as to how teaching of content subjects may be undertaken effectively with English as the LoLT. In Namibia, chemical bonding is part of the chemistry section of Physical Science, taught as a sub-topic under the Matter section, where the nature, characteristics, and behaviour of three states of matter are explained. The difficulty students have with chemical bonding is identified as being due to complex chemical concepts (Chittleborough & Mamiala, 2006), and the specialised language of the topic these concepts involve (Gilbert & Treagust, 2009). Additionally, this difficulty may be ascribed to lack of suitable pedagogic approaches, which is linked to science teachers not being fluent in the LoLT. Despite this link, Johnstone (1982) posits that addressing the challenge of teaching and learning chemical knowledge requires teachers’ understanding of three levels of representation: macroscopic, sub-microscopic, and symbolic. Addressing this challenge may be accomplished by using multimodality in teaching, which is achievable via intersemiosis of different semiotic modes, drawing from Systemic Functional Linguistics. This is due to non-linguistic modes also having the potential to make meaning as language does, and the fact that language alone cannot fully enable effective meaning-making in discourses that are inherently multimodal, such as science. Some studies have suggested that the intersemiosis of visual and verbal semiotic modes has the potential to enable more meaning-making of scientific discourse than either of these two alone. The study reported on in this thesis has built on such previous studies in order to explore the influences of a visual-verbal intersemiotic complementarity teaching approach on Grade 9 Namibian learners’ sense-making of chemical bonding. No studies from Namibia exploring these influences on Grade 9 learners could be found. This revealed the knowledge gap that this study aimed to contribute to filling. I accomplished this goal by embarking on a two-cycle action research study. The first cycle followed a traditional teaching approach and assessment, whereas the second cycle, the intervention, included a visual-verbal intersemiotic complementarity teaching approach and assessment. I achieved visual-verbal intersemiotic complementarity teaching and assessment by coordinating spoken and written language with visuals in the form of diagrams and physical models. The critical paradigm was adopted to explore the influences of this pedagogic approach, with the underlying aim of exploring the intervention approach for bringing about a change in learners’ sense-making of chemical bonding, compared to traditional approaches that do not consider intersemiosis. This study is informed by Vygotsky’s (1978) social constructivism to account for learning as a product of social construction, and Halliday’s (1978) Systemic Functional Linguistics to account for the role played by semiotic modes in making meanings. This study involved collecting qualitative data that were accessed via document analysis, structured lesson observation, the teacher’s and learners’ reflective journals, and the pre- and post-test. Collecting these data was facilitated by a critical friend. The results reveal a positive influence of the visual-verbal intersemiotic complementarity teaching approach on Grade 9 Namibian learners’ sense-making of chemical bonding. This influence was realised in the noticeable shift from the learners’ discourse (use of talk and visuals) being perceptual (which is less scientific) to being idea-based (which is more scientific). Learners were also found to be self-motivated and keen to learn complex chemical bonding concepts after the intervention – another sign of their making sense of the topic. The implications of this study include that visual-verbal intersemiotic complementarity should be considered a pedagogic approach to chemical bonding by curriculum developers and reviewers, teacher training institutions, and science textbook authors. , Thesis (MEd) -- Faculty of Education, Education, 2021
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  • Date Issued: 2021-04

An analysis of the countervailing measures used to address the anti-competitive effects of Government subsidies in the African Continental Free Trade Area

  • Authors: Matsimbi, Rhulani Shaun
  • Date: 2021-04
  • Subjects: Subsidies -- Law and legislation -- Africa , Agreement on Subsidies and Countervailing Measures (1994 April 15) , Trade regulation -- Africa , World Trade Organization , Antitrust law -- Africa , Restraint of trade -- Africa , African Continental Free Trade (AfCFTA) Agreement
  • Language: English
  • Type: thesis , text , Masters , LLM
  • Identifier: http://hdl.handle.net/10962/178330 , vital:42930
  • Description: Government subsidies are becoming more prevalent on the African continent. Subsidies allow the government to intervene in markets to incentivise more investment into nascent and struggling industries by improving the efficiency of firms in such industries. As such, subsidies form an essential part of some African countries’ industrialisation policies. However, the use of subsidies faces a challenge because of the prohibition contained in the World Trade Organisation’s (WTO) Agreement on Subsidies and Countervailing Measures (SCM Agreement). The SCM Agreement prohibits the granting of subsidies that are contingent on export performance or the use of domestic over imported content. While African countries have not faced challenges in the WTO for their use of these subsidies, this may change with the operation of the African Continental Free Trade (AfCFTA) Agreement. This is because the AfCFTA Agreement localises the WTO’s rules on subsidisation. This study critically examines the provisions in the AfCFTA Guidelines on the Implementation of Trade Remedies that regulate the use of export subsidies and subsidies contingent on the use of domestic content. It discusses how the absolute prohibition of these subsidies in the AfCFTA Agreement is not the most effective way to regulate their anti-competitive effects in the African continent. Specifically, this study discusses the role that competition policy might play in ensuring that export subsidies and local content subsidies are regulated in a manner that suits Africa’s context. Ultimately, this study concludes and recommends that the AfCFTA must develop unique rules to regulate subsidies in a way that caters to the needs of the continent. , Thesis (LLM) -- Faculty of Law, Law, 2021
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  • Date Issued: 2021-04

Design of immunosensor for the detection of C-reactive protein using oriented antibody immobilization

  • Authors: Adesina, Abiola Olanike
  • Date: 2020
  • Subjects: Uncatalogued
  • Language: English
  • Type: thesis , text , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/163080 , vital:41010 , https://dx.doi.org/10.21504/10962/163080
  • Description: Thesis (PhD)--Rhodes University, Science Faculty, Department of Chemistry, 2020.
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  • Date Issued: 2020

Exploring how Grade 9 Physical Science teachers mediate learning of the topic of chemical changes

  • Authors: Likando, Orrice Munukayumbwa
  • Date: 2021-04
  • Subjects: Science -- Study and teaching (Secondary) -- Namibia , Chemistry -- Study and teaching (Secondary) -- Namibia , Culturally relevant pedagogy , Pedagogical content knowledge , Prior learning -- Namibia
  • Language: English
  • Type: thesis , text , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/177918 , vital:42890
  • Description: The examiners’ reports for 2013-2018 indicated that learners consistently perform poorly in questions based on chemical changes. My assumption is that the reason why learners are challenged with understanding the topic of chemical changes could be due to the way this topic is taught. It is against this background that this study explored how grade 9 Physical Science teachers mediated learning of the topic of chemical changes. The study is underpinned by an interpretive paradigm. Within the interpretive paradigm, a qualitative case study research design was employed. It was conducted at two different schools in the Otjozondjupa region with two Physical Science teachers. Data were collected using semi-structured interviews, lesson observations, stimulated recall interviews, and teachers’ reflections. The study is informed by Vygotsky’s socio-cultural theory together with Shulman’s pedagogical content knowledge as the theoretical frameworks. A thematic approach to data analysis was adopted. That is, qualitative data were analysed inductively to come up with sub-themes to form themes. Moreover, validation and trustworthiness were completed through data triangulation, member checking, and watching videotaped lessons with the participants. The findings of this study revealed that the topic of chemical changes has many examples which can be used during mediation. Teachers seemed to be aware of integrating learners’ experiences into their lessons. Furthermore, they were aware that they should improvise resources during mediation of learning. In contrast, during lesson observations, the findings revealed an imbalance between this awareness and the actual knowledge of using easily accessible materials, and the elicitation and integration of prior knowledge throughout the science lessons. Moreover, hands-on practical activities were lacking in the mediation process and instead, traditional methods of teaching tended to dominate. Nonetheless, teachers’ reflections influenced them to analyse and strengthen their lessons. Thus, the study recommends that there is a need for teachers to have mentorships and platforms which can expose them to the knowledge of different types of easily accessible materials. This might strengthen their PCK. Teachers are also encouraged to do some reflections after very lesson as these have a potential to influence their pedagogical practices. , Thesis (MEd) -- Faculty of Education, Education, 2021
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  • Date Issued: 2021-04

The development, manufacture and characterisation of tenofovir encapsulated liposomes

  • Authors: Mungoshi, Fadzai Naomi
  • Date: 2020-04
  • Subjects: Uncatalogued
  • Language: English
  • Type: thesis , text , Masters , MSc (Pharmacy)
  • Identifier: http://hdl.handle.net/10962/164524 , vital:41126
  • Description: Thesis (MSc)--Rhodes University, Faculty of Pharmacy, Pharmaceutics, 2020
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  • Date Issued: 2020-04

Development of a low-cost bioprinting system for engineering of Human Tumour Models

  • Authors: Fanucci, Sidne
  • Date: 2020
  • Subjects: Uncatalogued
  • Language: English
  • Type: thesis , text , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/163295 , vital:41026
  • Description: Thesis (MSc)--Rhodes University, Faculty of Science, Biotechnology Innovation Centre, 2020.
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  • Date Issued: 2020
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