Design of Immunobiosensors for Detection of Tumor-Associated Anti-P53 Autoantibodies: Method Development
- Authors: Adeniyi, Omotayo Kayode
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/162988 , vital:41002 , 10.21504/10962/162988
- Description: Introduction -- Experimental -- Label-Free Impedimetric Sensing of Anti-P53ab... -- Fluorescent detection of Anti-P53ab -- Peroxidase-like activity of Fe3O4@SiNP-APTES-Au@Pd... -- Colorimetric detection of Anti-P53ab , Thesis (PhD)--Rhodes University, Science Faculty, Department of Chemistry, 2020. , Detection and profiling of circulating tumor-associated autoantibodies (TAAbs) are useful for screening and early-stage diagnosis of asymptomatic lung cancer. Immunobiosensor technologies aimed to accomplish the highly sensitive, rapid and low-cost detection of TAAbs can improve the early-stage detection of lung cancer. Immunobiosensors for the detection of anti-P53-tumour associated autoantibodies have been developed in this work. The design of sensing interfaces with immobilized P53 protein (P53ag) as a sensing element layer on a solid interface was investigated. Several methods of detecting anti-P53-antibodies (anti-P53ab) were investigated. These methods are label-free detection using electrochemical impedance spectroscopy (EIS) and two label techniques. The label-free electrochemical techniques utilize gold electrode pre-modified with a conducting layer of electrochemically grafted phenylethylamine for covalent immobilization of P53ag. The limit of anti-P53ab detection with the label-free EIS was 103.0 pg.ml-1. The labeled technique developed utilizes fluorescent, and peroxidase-like nanomaterial labeled antibody as a detection probe. For the fluorescence detection, fluorescent silica nanoparticles were synthesized by overloading FITC into the silica matrix and conjugated to detection antibody (anti-IgG). The detection of the anti-P53ab was based on the dissolution of the silica nanoparticles to release the loaded dye as a signal amplification strategy. The fluorescence detection was carried out on a microplate, and magnetic bead modified P53-antigen platforms and limit of detection (LoD) were 42.0 fg.ml-1 and 3.3 fg.ml-1 for anti-P53ab; respectively. Fe3O4@SiNP-APTES-Au@Pd hybrid nanoparticles were synthesized, and their peroxidase-like activity and colorimetric detection were evaluated. The Fe3O4@SiNP-APTES-Au@Pd exhibited comparable activity to HRP. The Fe3O4@SiNP-APTES-Au@Pd was conjugated to protein-G-anti-IgG for the detection of anti-P53ab on a microplate and cellulose paper platforms. The LoD was 20.0 fg.ml-1 and 63.0 fg.ml-1 for the microplate and cellulose paper platform; respectively. The potential application of the designed immunobiosensor was evaluated in simulated serum samples. The developed sensors showed higher detection sensitivity, stability and had a lower detection limit for anti-P53ab when compared with the ELISA based detection. The results have provided alternative and effective quantification approaches to ELISA and a promising future for multiplexed detection of tumor-associated autoantibodies. The developed methodologies in this thesis could be applied for the detection of other autoantibodies in other cancer types and auto-immune diseases.
- Full Text:
- Date Issued: 2020
- Authors: Adeniyi, Omotayo Kayode
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/162988 , vital:41002 , 10.21504/10962/162988
- Description: Introduction -- Experimental -- Label-Free Impedimetric Sensing of Anti-P53ab... -- Fluorescent detection of Anti-P53ab -- Peroxidase-like activity of Fe3O4@SiNP-APTES-Au@Pd... -- Colorimetric detection of Anti-P53ab , Thesis (PhD)--Rhodes University, Science Faculty, Department of Chemistry, 2020. , Detection and profiling of circulating tumor-associated autoantibodies (TAAbs) are useful for screening and early-stage diagnosis of asymptomatic lung cancer. Immunobiosensor technologies aimed to accomplish the highly sensitive, rapid and low-cost detection of TAAbs can improve the early-stage detection of lung cancer. Immunobiosensors for the detection of anti-P53-tumour associated autoantibodies have been developed in this work. The design of sensing interfaces with immobilized P53 protein (P53ag) as a sensing element layer on a solid interface was investigated. Several methods of detecting anti-P53-antibodies (anti-P53ab) were investigated. These methods are label-free detection using electrochemical impedance spectroscopy (EIS) and two label techniques. The label-free electrochemical techniques utilize gold electrode pre-modified with a conducting layer of electrochemically grafted phenylethylamine for covalent immobilization of P53ag. The limit of anti-P53ab detection with the label-free EIS was 103.0 pg.ml-1. The labeled technique developed utilizes fluorescent, and peroxidase-like nanomaterial labeled antibody as a detection probe. For the fluorescence detection, fluorescent silica nanoparticles were synthesized by overloading FITC into the silica matrix and conjugated to detection antibody (anti-IgG). The detection of the anti-P53ab was based on the dissolution of the silica nanoparticles to release the loaded dye as a signal amplification strategy. The fluorescence detection was carried out on a microplate, and magnetic bead modified P53-antigen platforms and limit of detection (LoD) were 42.0 fg.ml-1 and 3.3 fg.ml-1 for anti-P53ab; respectively. Fe3O4@SiNP-APTES-Au@Pd hybrid nanoparticles were synthesized, and their peroxidase-like activity and colorimetric detection were evaluated. The Fe3O4@SiNP-APTES-Au@Pd exhibited comparable activity to HRP. The Fe3O4@SiNP-APTES-Au@Pd was conjugated to protein-G-anti-IgG for the detection of anti-P53ab on a microplate and cellulose paper platforms. The LoD was 20.0 fg.ml-1 and 63.0 fg.ml-1 for the microplate and cellulose paper platform; respectively. The potential application of the designed immunobiosensor was evaluated in simulated serum samples. The developed sensors showed higher detection sensitivity, stability and had a lower detection limit for anti-P53ab when compared with the ELISA based detection. The results have provided alternative and effective quantification approaches to ELISA and a promising future for multiplexed detection of tumor-associated autoantibodies. The developed methodologies in this thesis could be applied for the detection of other autoantibodies in other cancer types and auto-immune diseases.
- Full Text:
- Date Issued: 2020
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.
- Full Text:
- Date Issued: 2020
- 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.
- Full Text:
- Date Issued: 2020
The relative suitability of knowledge paradigms to indigenous African resource management and their implications for environmental bioethics, environmental policy and food security
- Authors: Agbor Ambang, Oscar Mbi
- Date: 2020-04
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , M.Pharm
- Identifier: http://hdl.handle.net/10962/163091 , vital:41011
- Description: Thesis (M.Pharm)--Rhodes University, Faculty of Pharmacy, Pharmacy, 2020.
- Full Text:
- Date Issued: 2020-04
- Authors: Agbor Ambang, Oscar Mbi
- Date: 2020-04
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , M.Pharm
- Identifier: http://hdl.handle.net/10962/163091 , vital:41011
- Description: Thesis (M.Pharm)--Rhodes University, Faculty of Pharmacy, Pharmacy, 2020.
- Full Text:
- Date Issued: 2020-04
Exploring the influences of an intersemiotic complementarity teaching approach on Grade 9 Namibian learners’ sense-making of chemical bonding
- Aikanga, Frans Paulus Shintaleleni
- 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
- Full Text:
- Date Issued: 2021-04
- 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
- Full Text:
- Date Issued: 2021-04
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
- Full Text:
- Date Issued: 2021-04
- 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
- Full Text:
- Date Issued: 2021-04
Poppehysie
- Authors: Arendse, Ashwin Albert
- Date: 2021-04
- Subjects: Swartlandse Kaaps poetry -- 21st century , Creative writing (Higher education) -- South Africa , Diaries -- Authorship , Afrikaans poetry -- 21st century , African literature -- History and criticism
- Language: Afrikaans
- Type: thesis , text , Masters , MA
- Identifier: http://hdl.handle.net/10962/178259 , vital:42925
- Description: My thesis, is geskryf in Swartlandse Kaaps, ’n streeksvariant van Kaaps. Die poems is free verses wat afspeel tien ie backdrop van Malmesbury en Stellenbosch se “Coloured areas” mette analysis van dialect en ideolect wat eie is annie mense wat ampe altyd feature innie stories wat ek vertel. Die thesis explore die liefde asse konsep. Dit kyk na hoe die desperate need vi absent liefde ’n toxic relationship feed tussen ’n jong couple ennie destructive impact van liefde oppe pesoon wie nooit geleer was hoe om lief te wies vi annes ie. Dan kyk ek oek na hoe die previous generations, dit van my ma en pa liefde reject et asse unaffordable excess inne community wat brutal en harsh is. Antonio Gramsci se konsep vannie organic intellectual, dien asse philosophical underpinning virrie thesis d.w.s die hoofkarakter dien asse orator virrie intellectual en cultural insights wattie everyman in sy community nie self kan express ie. Die organic intellectual express díe thoughts innie cultural taal van sy social class. Die thesis explore stories soes it vetel wôd dee mense soes my oupa en mense wattie altyd aware is dat hulle stories in hulle in hettie. In dai way val it tot some degree binne die terrain van oral traditions. Die thesis wil dip into die collective conscious vanne social group wat die worst aspects van liewe in Syd-Afrika experience et. Ek voel free verse is ie ideal form van expression vi my in regards tot die skryf van die thesis, omdat ek daamee die line successfully kan blur tussen ie ‘language of the people’ en my eie individual leaning toward poetic language en forms. In terms van style draw ek op vorige digbundels in Kaaps, most notably op Nathan Trantraal se baie controlled, free verse digbundel, ‘Alles het niet kom wôd,’en Ronelda S. Kamfer se technique van ‘oorvertel’, in haa digbundel ‘grond/Santekraam’. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2021
- Full Text:
- Date Issued: 2021-04
- Authors: Arendse, Ashwin Albert
- Date: 2021-04
- Subjects: Swartlandse Kaaps poetry -- 21st century , Creative writing (Higher education) -- South Africa , Diaries -- Authorship , Afrikaans poetry -- 21st century , African literature -- History and criticism
- Language: Afrikaans
- Type: thesis , text , Masters , MA
- Identifier: http://hdl.handle.net/10962/178259 , vital:42925
- Description: My thesis, is geskryf in Swartlandse Kaaps, ’n streeksvariant van Kaaps. Die poems is free verses wat afspeel tien ie backdrop van Malmesbury en Stellenbosch se “Coloured areas” mette analysis van dialect en ideolect wat eie is annie mense wat ampe altyd feature innie stories wat ek vertel. Die thesis explore die liefde asse konsep. Dit kyk na hoe die desperate need vi absent liefde ’n toxic relationship feed tussen ’n jong couple ennie destructive impact van liefde oppe pesoon wie nooit geleer was hoe om lief te wies vi annes ie. Dan kyk ek oek na hoe die previous generations, dit van my ma en pa liefde reject et asse unaffordable excess inne community wat brutal en harsh is. Antonio Gramsci se konsep vannie organic intellectual, dien asse philosophical underpinning virrie thesis d.w.s die hoofkarakter dien asse orator virrie intellectual en cultural insights wattie everyman in sy community nie self kan express ie. Die organic intellectual express díe thoughts innie cultural taal van sy social class. Die thesis explore stories soes it vetel wôd dee mense soes my oupa en mense wattie altyd aware is dat hulle stories in hulle in hettie. In dai way val it tot some degree binne die terrain van oral traditions. Die thesis wil dip into die collective conscious vanne social group wat die worst aspects van liewe in Syd-Afrika experience et. Ek voel free verse is ie ideal form van expression vi my in regards tot die skryf van die thesis, omdat ek daamee die line successfully kan blur tussen ie ‘language of the people’ en my eie individual leaning toward poetic language en forms. In terms van style draw ek op vorige digbundels in Kaaps, most notably op Nathan Trantraal se baie controlled, free verse digbundel, ‘Alles het niet kom wôd,’en Ronelda S. Kamfer se technique van ‘oorvertel’, in haa digbundel ‘grond/Santekraam’. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2021
- Full Text:
- Date Issued: 2021-04
A comprehensive approach to scalability assessment of ICTD projects : a case study of ICT4RED
- Authors: Baduza, Gugulethu Qhawekazi
- Date: 2021-04
- Subjects: To be added
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/178435 , vital:42939
- Description: Access restricted until April 2023. , Thesis (PhD) -- Faculty of Commerce, Information Systems, 2021
- Full Text:
- Date Issued: 2021-04
- Authors: Baduza, Gugulethu Qhawekazi
- Date: 2021-04
- Subjects: To be added
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/178435 , vital:42939
- Description: Access restricted until April 2023. , Thesis (PhD) -- Faculty of Commerce, Information Systems, 2021
- Full Text:
- Date Issued: 2021-04
A study of four-dimensional oscillator groups and the associated left-invariant control affine systems
- Authors: Biggs, Rory
- Date: 2012
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/164941 , vital:41186
- Description: Thesis (MSc)--Rhodes University, Faculty of Science, Department of Mathematics, 2012
- Full Text:
- Date Issued: 2012
- Authors: Biggs, Rory
- Date: 2012
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/164941 , vital:41186
- Description: Thesis (MSc)--Rhodes University, Faculty of Science, Department of Mathematics, 2012
- Full Text:
- Date Issued: 2012
The effects of aspect, directional heating and depth on bedrock temperatures and the potential relationship with thermal fatigue weathering
- Authors: Breytenbach, Izak Johannes
- Date: 2021-04
- Subjects: Weathering -- South Africa -- Karoo , Shields (Geology) -- South Africa -- Karoo , Shields (Geology) -- Thermal properties , Tillite -- South Africa -- Karoo
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/177688 , vital:42847 , 10.21504/10962/177688
- Description: Geomorphological weathering processes and their relationship with temperature fluctuations are frequently researched. These research efforts are mostly restricted to surface conditions where soils, loose-lying rocks or rock outcrops are assessed. However, there is a shortcoming in the understanding of the thermal properties in a rock mass, particularly in the upper metres below the surface, as this has not been investigated or researched in any great detail. The research reported here is unique in this regard as it exploited the use of rotary core boreholes in tillite bedrock in the Karoo (Western Cape, South Africa) which were drilled as part of an invasive materials investigation for a proposed new hard rock quarry to supply road stone. Temperature data were captured on a bedrock ridge hosting tillite outcrop with a strong east to west orientation. The site work was done in two separate phases. The initial phase of research saw data being captured for one year on two aspects (i.e. north and south) at a depth of 0.3 m. This was followed by the second (more detailed) phase, where three aspects were assessed (i.e. north, south and a flat crest), but at depths of 0.3 m, 2.0 m and 6.0 m, totalling nine data acquisition points. The second investigation phase gathered data for seven months. Supplementary weather data were also captured for the site. Subsequent data analyses revealed that there is much to learn about the thermal behaviour of bedrock in the upper metres below the surface, and that the temperature properties or thermal regimes are not as simple as often assumed. Temperature differences related to aspect are not only surficial, but are transmitted to underlying bedrock, and notable temperature differences were measurable to a depth of at least 6.0 m. Seasonal temperature fluctuations also have a pronounced effect on the rock mass temperatures and it was proven that deeper parts of the bedrock accumulate and dissipate heat at different (i.e. retarded) rates compared with shallower parts of the rock mass, creating suitable thermal conditions to induce thermal fatigue. Thermal properties were also proven to be non-linear. During analyses, the concept of temperature inversions was proven, whereby one part of the bedrock becomes hotter or cooler relative to another/adjacent part of the bedrock, compared with its earlier temperature state. It was argued that these temperature inversions may exacerbate thermal fatigue. This research proved that aspect (i.e. directional heating) and depth need to be considered when analysing thermal regimes in a rock mass, as these have a distinct influence. The effects which manifest themselves create suitable conditions for thermal fatigue, not only near the surface but also at depth in the bedrock. Lastly, the effects of meteorological conditions on shallow bedrock temperatures were assessed. Preliminary findings suggest that boundary conditions and meteorological processes may indeed affect shallow bedrock temperatures, but only under certain circumstances and not to the same extent as reported in the literature for conditions researched at the surface. Wind temperature relative to the rock temperature, as well as a combination of wind and rain were found to be the most significant factors. , Thesis (PhD) -- Faculty of Science, Geography, 2021
- Full Text:
- Date Issued: 2021-04
- Authors: Breytenbach, Izak Johannes
- Date: 2021-04
- Subjects: Weathering -- South Africa -- Karoo , Shields (Geology) -- South Africa -- Karoo , Shields (Geology) -- Thermal properties , Tillite -- South Africa -- Karoo
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/177688 , vital:42847 , 10.21504/10962/177688
- Description: Geomorphological weathering processes and their relationship with temperature fluctuations are frequently researched. These research efforts are mostly restricted to surface conditions where soils, loose-lying rocks or rock outcrops are assessed. However, there is a shortcoming in the understanding of the thermal properties in a rock mass, particularly in the upper metres below the surface, as this has not been investigated or researched in any great detail. The research reported here is unique in this regard as it exploited the use of rotary core boreholes in tillite bedrock in the Karoo (Western Cape, South Africa) which were drilled as part of an invasive materials investigation for a proposed new hard rock quarry to supply road stone. Temperature data were captured on a bedrock ridge hosting tillite outcrop with a strong east to west orientation. The site work was done in two separate phases. The initial phase of research saw data being captured for one year on two aspects (i.e. north and south) at a depth of 0.3 m. This was followed by the second (more detailed) phase, where three aspects were assessed (i.e. north, south and a flat crest), but at depths of 0.3 m, 2.0 m and 6.0 m, totalling nine data acquisition points. The second investigation phase gathered data for seven months. Supplementary weather data were also captured for the site. Subsequent data analyses revealed that there is much to learn about the thermal behaviour of bedrock in the upper metres below the surface, and that the temperature properties or thermal regimes are not as simple as often assumed. Temperature differences related to aspect are not only surficial, but are transmitted to underlying bedrock, and notable temperature differences were measurable to a depth of at least 6.0 m. Seasonal temperature fluctuations also have a pronounced effect on the rock mass temperatures and it was proven that deeper parts of the bedrock accumulate and dissipate heat at different (i.e. retarded) rates compared with shallower parts of the rock mass, creating suitable thermal conditions to induce thermal fatigue. Thermal properties were also proven to be non-linear. During analyses, the concept of temperature inversions was proven, whereby one part of the bedrock becomes hotter or cooler relative to another/adjacent part of the bedrock, compared with its earlier temperature state. It was argued that these temperature inversions may exacerbate thermal fatigue. This research proved that aspect (i.e. directional heating) and depth need to be considered when analysing thermal regimes in a rock mass, as these have a distinct influence. The effects which manifest themselves create suitable conditions for thermal fatigue, not only near the surface but also at depth in the bedrock. Lastly, the effects of meteorological conditions on shallow bedrock temperatures were assessed. Preliminary findings suggest that boundary conditions and meteorological processes may indeed affect shallow bedrock temperatures, but only under certain circumstances and not to the same extent as reported in the literature for conditions researched at the surface. Wind temperature relative to the rock temperature, as well as a combination of wind and rain were found to be the most significant factors. , Thesis (PhD) -- Faculty of Science, Geography, 2021
- Full Text:
- Date Issued: 2021-04
The physical activity levels and preferences of South African breast cancer survivors : a pilot study
- Authors: Campbell, Belinda Claire
- Date: 2021-04
- Subjects: Breast -- Cancer , Cancer -- Patients -- South Africa , Cancer -- Patients -- Rehabilitation , Exercise -- Health aspects , Godin leisure-time activity questionnaire (GLTPAQ) , International Physical Activity Questionnaire (IPAQ)
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/177748 , vital:42855
- Description: Introduction: Breast cancer is currently the most commonly diagnosed cancer in South African women. Physical activity has proven to have preventative, treatment and management benefits for breast cancer and other cancers and exercise has been found as both viable and safe during cancer treatment and recovery. However, there is limited research on breast cancer and the levels and preferences of physical activity and sedentary behaviour in a South African context. Therefore, the purpose of this study was to identify levels of physical activity and sedentary behaviour of South African breast cancer survivors and to investigate the physical activity advice and participation preferences of these participants. Methods: A cross-sectional research design was implemented to identify the physical activity, sedentary behaviour levels and exercise preferences of 48 South African breast cancer survivors (age range 45 years). An online survey comprising demographic and anthropometric questions, the Godin leisure-time activity questionnaire (GLTPAQ), the International Physical Activity Questionnaire (IPAQ) and an exercise preference questionnaire was presented to participating breast cancer survivors in order to i) identify the levels of physical activity and sedentary behaviour engaged in, ii) obtain demographic and anthropometric information and iii) identify exercise preferences. A linear mixed model regression was used to examine potential associations between demographic and anthropometric variables and physical activity levels. Chi-squared and Pearson’s Product-Moment correlation tests were used to identify relationships between categorical and numerical variables. A correlation matrix was generated to further explore any correlations. Statistical significance for all measures was set at p<0.05. Results: The mean age of the group was 49 ± 9.87 years. The most common time since diagnosis was <5 years ago and the most common stage of breast cancer was stage I. The mean BMI was 27.87 ± 5.53kg/m2. The most common treatment combination was surgery with either chemotherapy or radiation. According to the leisure score index (LSI) the majority of the group (56%) was active and according to IPAQ data 60% were meeting physical activity guidelines. The highest physical activity levels were seen in the average weekly minutes of moderate-intensity activity, and there was a strong, non-significant positive correlation (p>0.05, R2 = 0.95) between moderate-intensity physical activity and total physical activity levels. High levels of weekly sedentary behaviour and sitting time (302.60 ± 169.96 minutes) were reported. A weak, non-significant, positive correlation was found between total sedentary time and BMI (p>0.05, R2 = 0.1). A weak, non-significant, negative correlation was found between age and sedentary time (p>0.05, R2 = 0.002). More participants below 50 years were insufficiently active compared to above the age of 50 years. 1.7 to 2.6 years since diagnosis saw the greatest number of insufficiently active survivors and the category over 2.6 years since diagnosis saw the most active survivors. Most breast cancer survivors (71.10% & 82.05%) indicated being interested in and feeling capable of participating in an exercise programme (p>0.05, R2 = 0.72). The favoured preference for receiving physical activity advice was face-to-face with an exercise specialist at a cancer centre before treatment. Participation preferences included starting a programme immediately after treatment, in a home-based setting with one or two other people, where walking and a moderate exercise intensity were the preferred exercise type and level of intensity. Data collection occurred both immediately prior to (42% of participants) and during (56% of participants) the South African Covid-19 lockdown, so the results should be seen in light of this context. Conclusion: The current study is one of the first to explore physical activity rates and preferences of South African breast cancer survivors. As a group and individually these survivors were meeting public physical activity guidelines and engaging in the recommended weekly minutes. The high sitting time coupled with the high overweight and obesity levels highlight the need for positive behavioural changes including improved levels of physical activity and reduced sedentary behaviour. These changes need involvement from the numerous levels of society that affect health. Broad physical activity guidelines need to be developed not only to improve physical activity levels in breast cancer survivors but to work as a preventative measure by facilitating physical activity promotion in the general population. The findings of this study demonstrate that this group of South African breast cancer survivors is open to physical activity advice, to programmes and to improving physical activity levels. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2021
- Full Text:
- Date Issued: 2021-04
- Authors: Campbell, Belinda Claire
- Date: 2021-04
- Subjects: Breast -- Cancer , Cancer -- Patients -- South Africa , Cancer -- Patients -- Rehabilitation , Exercise -- Health aspects , Godin leisure-time activity questionnaire (GLTPAQ) , International Physical Activity Questionnaire (IPAQ)
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/177748 , vital:42855
- Description: Introduction: Breast cancer is currently the most commonly diagnosed cancer in South African women. Physical activity has proven to have preventative, treatment and management benefits for breast cancer and other cancers and exercise has been found as both viable and safe during cancer treatment and recovery. However, there is limited research on breast cancer and the levels and preferences of physical activity and sedentary behaviour in a South African context. Therefore, the purpose of this study was to identify levels of physical activity and sedentary behaviour of South African breast cancer survivors and to investigate the physical activity advice and participation preferences of these participants. Methods: A cross-sectional research design was implemented to identify the physical activity, sedentary behaviour levels and exercise preferences of 48 South African breast cancer survivors (age range 45 years). An online survey comprising demographic and anthropometric questions, the Godin leisure-time activity questionnaire (GLTPAQ), the International Physical Activity Questionnaire (IPAQ) and an exercise preference questionnaire was presented to participating breast cancer survivors in order to i) identify the levels of physical activity and sedentary behaviour engaged in, ii) obtain demographic and anthropometric information and iii) identify exercise preferences. A linear mixed model regression was used to examine potential associations between demographic and anthropometric variables and physical activity levels. Chi-squared and Pearson’s Product-Moment correlation tests were used to identify relationships between categorical and numerical variables. A correlation matrix was generated to further explore any correlations. Statistical significance for all measures was set at p<0.05. Results: The mean age of the group was 49 ± 9.87 years. The most common time since diagnosis was <5 years ago and the most common stage of breast cancer was stage I. The mean BMI was 27.87 ± 5.53kg/m2. The most common treatment combination was surgery with either chemotherapy or radiation. According to the leisure score index (LSI) the majority of the group (56%) was active and according to IPAQ data 60% were meeting physical activity guidelines. The highest physical activity levels were seen in the average weekly minutes of moderate-intensity activity, and there was a strong, non-significant positive correlation (p>0.05, R2 = 0.95) between moderate-intensity physical activity and total physical activity levels. High levels of weekly sedentary behaviour and sitting time (302.60 ± 169.96 minutes) were reported. A weak, non-significant, positive correlation was found between total sedentary time and BMI (p>0.05, R2 = 0.1). A weak, non-significant, negative correlation was found between age and sedentary time (p>0.05, R2 = 0.002). More participants below 50 years were insufficiently active compared to above the age of 50 years. 1.7 to 2.6 years since diagnosis saw the greatest number of insufficiently active survivors and the category over 2.6 years since diagnosis saw the most active survivors. Most breast cancer survivors (71.10% & 82.05%) indicated being interested in and feeling capable of participating in an exercise programme (p>0.05, R2 = 0.72). The favoured preference for receiving physical activity advice was face-to-face with an exercise specialist at a cancer centre before treatment. Participation preferences included starting a programme immediately after treatment, in a home-based setting with one or two other people, where walking and a moderate exercise intensity were the preferred exercise type and level of intensity. Data collection occurred both immediately prior to (42% of participants) and during (56% of participants) the South African Covid-19 lockdown, so the results should be seen in light of this context. Conclusion: The current study is one of the first to explore physical activity rates and preferences of South African breast cancer survivors. As a group and individually these survivors were meeting public physical activity guidelines and engaging in the recommended weekly minutes. The high sitting time coupled with the high overweight and obesity levels highlight the need for positive behavioural changes including improved levels of physical activity and reduced sedentary behaviour. These changes need involvement from the numerous levels of society that affect health. Broad physical activity guidelines need to be developed not only to improve physical activity levels in breast cancer survivors but to work as a preventative measure by facilitating physical activity promotion in the general population. The findings of this study demonstrate that this group of South African breast cancer survivors is open to physical activity advice, to programmes and to improving physical activity levels. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2021
- Full Text:
- Date Issued: 2021-04
Creative Cities and Regional Development: The Case of Makhanda and the Creative City Project
- Authors: Campbell, Guy John
- Date: 2021
- Subjects: To be assigned
- Language: English
- Type: thesis , text , Masters , MCOM
- Identifier: http://hdl.handle.net/10962/174448 , vital:42478
- Description: Thesis (MSc)--Rhodes University, Faculty of Commerce, Economics and Economic History, 2020
- Full Text:
- Date Issued: 2021
- Authors: Campbell, Guy John
- Date: 2021
- Subjects: To be assigned
- Language: English
- Type: thesis , text , Masters , MCOM
- Identifier: http://hdl.handle.net/10962/174448 , vital:42478
- Description: Thesis (MSc)--Rhodes University, Faculty of Commerce, Economics and Economic History, 2020
- Full Text:
- Date Issued: 2021
An exploratory investigation into an Integrated Vulnerability and Patch Management Framework
- Authors: Carstens, Duane
- Date: 2021-04
- Subjects: Computer security , Computer security -- Management , Computer networks -- Security measures , Patch Management , Integrated Vulnerability
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/177940 , vital:42892
- Description: In the rapidly changing world of cybersecurity, the constant increase of vulnerabilities continues to be a prevalent issue for many organisations. Malicious actors are aware that most organisations cannot timeously patch known vulnerabilities and are ill-prepared to protect against newly created vulnerabilities where a signature or an available patch has not yet been created. Consequently, information security personnel face ongoing challenges to mitigate these risks. In this research, the problem of remediation in a world of increasing vulnerabilities is considered. The current paradigm of vulnerability and patch management is reviewed using a pragmatic approach to all associated variables of these services / practices and, as a result, what is working and what is not working in terms of remediation is understood. In addition to the analysis, a taxonomy is created to provide a graphical representation of all associated variables to vulnerability and patch management based on existing literature. Frameworks currently being utilised in the industry to create an effective engagement model between vulnerability and patch management services are considered. The link between quantifying a threat, vulnerability and consequence; what Microsoft has available for patching; and the action plan for resulting vulnerabilities is explored. Furthermore, the processes and means of communication between each of these services are investigated to ensure there is effective remediation of vulnerabilities, ultimately improving the security risk posture of an organisation. In order to effectively measure the security risk posture, progress is measured between each of these services through a single averaged measurement metric. The outcome of the research highlights influencing factors that impact successful vulnerability management, in line with identified themes from the research taxonomy. These influencing factors are however significantly undermined due to resources within the same organisations not having a clear and consistent understanding of their role, organisational capabilities and objectives for effective vulnerability and patch management within their organisations. , Thesis (MSc) -- Faculty of Science, Computer Science, 2021
- Full Text:
- Date Issued: 2021-04
- Authors: Carstens, Duane
- Date: 2021-04
- Subjects: Computer security , Computer security -- Management , Computer networks -- Security measures , Patch Management , Integrated Vulnerability
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/177940 , vital:42892
- Description: In the rapidly changing world of cybersecurity, the constant increase of vulnerabilities continues to be a prevalent issue for many organisations. Malicious actors are aware that most organisations cannot timeously patch known vulnerabilities and are ill-prepared to protect against newly created vulnerabilities where a signature or an available patch has not yet been created. Consequently, information security personnel face ongoing challenges to mitigate these risks. In this research, the problem of remediation in a world of increasing vulnerabilities is considered. The current paradigm of vulnerability and patch management is reviewed using a pragmatic approach to all associated variables of these services / practices and, as a result, what is working and what is not working in terms of remediation is understood. In addition to the analysis, a taxonomy is created to provide a graphical representation of all associated variables to vulnerability and patch management based on existing literature. Frameworks currently being utilised in the industry to create an effective engagement model between vulnerability and patch management services are considered. The link between quantifying a threat, vulnerability and consequence; what Microsoft has available for patching; and the action plan for resulting vulnerabilities is explored. Furthermore, the processes and means of communication between each of these services are investigated to ensure there is effective remediation of vulnerabilities, ultimately improving the security risk posture of an organisation. In order to effectively measure the security risk posture, progress is measured between each of these services through a single averaged measurement metric. The outcome of the research highlights influencing factors that impact successful vulnerability management, in line with identified themes from the research taxonomy. These influencing factors are however significantly undermined due to resources within the same organisations not having a clear and consistent understanding of their role, organisational capabilities and objectives for effective vulnerability and patch management within their organisations. , Thesis (MSc) -- Faculty of Science, Computer Science, 2021
- Full Text:
- Date Issued: 2021-04
Former farm workers of foreign descent in communal areas in post-fast track Zimbabwe : the case of Shamva District
- Authors: Chadambuka, Patience
- Date: 2021-10-29
- Subjects: Migrant agricultural laborers -- Zimbabwe -- Shamva District , Agricultural laborers, Foreign -- Zimbabwe -- Shamva District , Land reform -- Zimbabwe , Belonging (Social psychology) -- Zimbabwe -- Shamva District , Social integration-- Zimbabwe -- Shamva District , Fast Track Land Reform Programme (FTLRP)
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/178420 , vital:42938 , 10.21504/10962/178420
- Description: Land and ethnicity continue to condition contestations in relation to belonging amongst rural Zimbabweans. The colonial era defined Zimbabwe’s land politics in a highly racialised and ethnicised manner. Racially, the colonial era gave birth to white-owned fertile farm lands, while blacks (or Africans) were resettled in agriculturally-unproductive Reserves, later referred to as communal areas in the post-colonial era. Though they were initially created with a segregatory and oppressive intent bent on disenfranchising native Africans, the Reserves became a definitive landscape embedded in ethnic and ancestral belonging for the autochthonous Natives. The Reserves were created exclusively for autochthonous Africans, and the colonial administration ensured that foreign migrant Africans recruited mainly as covenanted labour from nearby colonies would not be accommodated and consequently belong in Reserves. Migrant Africans were instead domiciled in white commercial farms, mines and urban areas, and deprived of land rights accorded to the autochthones. In the case of white farms specifically, the labourers experienced a conditional belonging (to the farm). This overall exclusionary system was later inherited and maintained by the post-colonial Zimbabwean government, up until the year 2000. Zimbabwe’s highly documented Fast Track Land Reform Programme (FTLRP) from the year 2000 did away with the entrenched racial bifurcations of land, as white commercial farms became fast track farms. However, it did not undercut the existence of communal areas. The FTLRP had a profound effect on the lives of commercial farm workers, particularly those of foreign origin who had no other home or source of livelihood to fall back on after fast track displacements. Some though sought to move into communal areas, from which they had been excluded previously. Within this context, most scholarly studies of the post fast track period ignore the plight of former farm workers especially those that moved to, and into, communal areas. This ethnographic study, specifically of former farm workers of foreign origin in Shamva communal areas, therefore seeks to contribute to Zimbabwean studies in this regard. It documents and examines the perceptions, practices and lived experiences of former farm workers of foreign origin now residing in the Bushu communal areas of Shamva, and how they interface with Bushu autochthones in seeking to belong to Bushu. This is pursued by way of qualitative research methods (including lengthy stays in the study sites) as well as through the use of a theoretical framing focusing on lifeworlds, interfaces, belonging, othering and strangerhood. Key findings reveal that belonging by the former farm workers in Bushu entails a non-linear and convoluted process characterised by a series of contestations around for instance land shortages, limited livelihood strategies and cultural difference. This project of belonging does not entail assimilation on the part of the former farm workers, as they continue to uphold certain historical practices, leading to a form of co-existence between the autochthones and allochthones in Bushu. In this way, the former farm workers seem to develop a conditional belonging in (and to) Bushu, albeit different than the one experienced on white farms in the past. , Thesis (PhD) -- Faculty of Humanities, Sociology, 2021
- Full Text:
- Date Issued: 2021-10-29
- Authors: Chadambuka, Patience
- Date: 2021-10-29
- Subjects: Migrant agricultural laborers -- Zimbabwe -- Shamva District , Agricultural laborers, Foreign -- Zimbabwe -- Shamva District , Land reform -- Zimbabwe , Belonging (Social psychology) -- Zimbabwe -- Shamva District , Social integration-- Zimbabwe -- Shamva District , Fast Track Land Reform Programme (FTLRP)
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/178420 , vital:42938 , 10.21504/10962/178420
- Description: Land and ethnicity continue to condition contestations in relation to belonging amongst rural Zimbabweans. The colonial era defined Zimbabwe’s land politics in a highly racialised and ethnicised manner. Racially, the colonial era gave birth to white-owned fertile farm lands, while blacks (or Africans) were resettled in agriculturally-unproductive Reserves, later referred to as communal areas in the post-colonial era. Though they were initially created with a segregatory and oppressive intent bent on disenfranchising native Africans, the Reserves became a definitive landscape embedded in ethnic and ancestral belonging for the autochthonous Natives. The Reserves were created exclusively for autochthonous Africans, and the colonial administration ensured that foreign migrant Africans recruited mainly as covenanted labour from nearby colonies would not be accommodated and consequently belong in Reserves. Migrant Africans were instead domiciled in white commercial farms, mines and urban areas, and deprived of land rights accorded to the autochthones. In the case of white farms specifically, the labourers experienced a conditional belonging (to the farm). This overall exclusionary system was later inherited and maintained by the post-colonial Zimbabwean government, up until the year 2000. Zimbabwe’s highly documented Fast Track Land Reform Programme (FTLRP) from the year 2000 did away with the entrenched racial bifurcations of land, as white commercial farms became fast track farms. However, it did not undercut the existence of communal areas. The FTLRP had a profound effect on the lives of commercial farm workers, particularly those of foreign origin who had no other home or source of livelihood to fall back on after fast track displacements. Some though sought to move into communal areas, from which they had been excluded previously. Within this context, most scholarly studies of the post fast track period ignore the plight of former farm workers especially those that moved to, and into, communal areas. This ethnographic study, specifically of former farm workers of foreign origin in Shamva communal areas, therefore seeks to contribute to Zimbabwean studies in this regard. It documents and examines the perceptions, practices and lived experiences of former farm workers of foreign origin now residing in the Bushu communal areas of Shamva, and how they interface with Bushu autochthones in seeking to belong to Bushu. This is pursued by way of qualitative research methods (including lengthy stays in the study sites) as well as through the use of a theoretical framing focusing on lifeworlds, interfaces, belonging, othering and strangerhood. Key findings reveal that belonging by the former farm workers in Bushu entails a non-linear and convoluted process characterised by a series of contestations around for instance land shortages, limited livelihood strategies and cultural difference. This project of belonging does not entail assimilation on the part of the former farm workers, as they continue to uphold certain historical practices, leading to a form of co-existence between the autochthones and allochthones in Bushu. In this way, the former farm workers seem to develop a conditional belonging in (and to) Bushu, albeit different than the one experienced on white farms in the past. , Thesis (PhD) -- Faculty of Humanities, Sociology, 2021
- Full Text:
- Date Issued: 2021-10-29
Structural determinants of the HSP90-Fibronectin interaction and implications for fibrillogenesis
- Authors: Chakraborty, Abir
- Date: 2022-04-08
- Subjects: To be added
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/294572 , vital:57234
- Description: Thesis embargoed. Release date April 2024. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2022
- Full Text:
- Date Issued: 2022-04-08
- Authors: Chakraborty, Abir
- Date: 2022-04-08
- Subjects: To be added
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/294572 , vital:57234
- Description: Thesis embargoed. Release date April 2024. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2022
- Full Text:
- Date Issued: 2022-04-08
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.
- Full Text:
- Date Issued: 2021-04
- 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.
- Full Text:
- Date Issued: 2021-04
Formulation and characterisation of a combination captopril and hydrochlorothiazide microparticulate dosage form for paediatric use
- Chikukwa, Mellisa Tafadzwa Ruramai
- Authors: Chikukwa, Mellisa Tafadzwa Ruramai
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/163216 , vital:41019 , doi:10.21504/10962/163216
- Description: Thesis (PhD)--Rhodes University, Pharmacy Faculty, Department of Pharmaceutics, 2020
- Full Text:
- Date Issued: 2020
- Authors: Chikukwa, Mellisa Tafadzwa Ruramai
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/163216 , vital:41019 , doi:10.21504/10962/163216
- Description: Thesis (PhD)--Rhodes University, Pharmacy Faculty, Department of Pharmaceutics, 2020
- Full Text:
- Date Issued: 2020
Long Waves of Strikes in South Africa: 1886–2019
- Authors: Cottle, Eddie
- Date: 2020
- Subjects: Strikes and lockouts South Africa , Long waves (Economics) South Africa , Business cycles South Africa , Industrial mobilization South Africa , Collective bargaining South Africa , Institutionalisation , Labor unions South Africa
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/163228 , vital:41020 , doi:10.21504/10962/163228
- Description: Thesis (PhD)--Rhodes University, Faculty of Humanities, Institute for Social and Economic Research (ISER), 2020.
- Full Text:
- Date Issued: 2020
- Authors: Cottle, Eddie
- Date: 2020
- Subjects: Strikes and lockouts South Africa , Long waves (Economics) South Africa , Business cycles South Africa , Industrial mobilization South Africa , Collective bargaining South Africa , Institutionalisation , Labor unions South Africa
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/163228 , vital:41020 , doi:10.21504/10962/163228
- Description: Thesis (PhD)--Rhodes University, Faculty of Humanities, Institute for Social and Economic Research (ISER), 2020.
- Full Text:
- Date Issued: 2020
Unpacking the link between adaptive capacity, assets and responses of rural livelihoods facing multiple stressors in the Eastern Cape
- Dalu, Mwazvita Tapiwa Beatrice
- Authors: Dalu, Mwazvita Tapiwa Beatrice
- Date: 2020
- Language: English
- Type: thesis , text , Doctoral , Ph.D
- Identifier: http://hdl.handle.net/10962/147103 , vital:38593 , doi:10.21504/10962/147103
- Description: Thesis (PhD.)--Rhodes University, Faculty of Science, Environmental Science, 2020.
- Full Text:
- Date Issued: 2020
- Authors: Dalu, Mwazvita Tapiwa Beatrice
- Date: 2020
- Language: English
- Type: thesis , text , Doctoral , Ph.D
- Identifier: http://hdl.handle.net/10962/147103 , vital:38593 , doi:10.21504/10962/147103
- Description: Thesis (PhD.)--Rhodes University, Faculty of Science, Environmental Science, 2020.
- Full Text:
- Date Issued: 2020
An Archive of Upset : the Shift from Commissioning to Curating through South Africa’s Representations at the Bienal de São Paulo and the Interstitial Nexus of Leonard Tshehla Mohapi Matsoso
- Authors: Dantas, Nancy Isabel
- Date: 2021-04
- Subjects: Bienal Internacional de São Paulo , Curatorship , Art -- Commissioning , Art -- Political aspects , Matsoso, Leonard Tshehla Mohapi
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/174492 , vital:42482 , https://doi.org/10.21504/10962/174492
- Description: This thesis explores the distinction between commissioning and curating, adopting the Bienal de São Paulo (or Bienal) as its conceptual propeller and point of departure. The thesis regards exhibitions as palimpsests, in other words, platforms built on previous conscious or sublimated models, beyond the Venetian model inaugurated in 1895. By looking at world expositions, particularly the Cape presence at the Colonial and Indian Exhibition of 1886, this project traces a lineage of commissioners, from Sir Henry Cole to Sydney Cowper through to the Director of the Pretoria Art Museum, Albert Werth. It distinguishes these men, their vision and allegiances from the curatorial model instantiated in South Africa by the late Okwui Enwezor as a consequence of the Second Johannesburg Biennale, held in 1997. The aim of this research has been to provide a partial but crucial account of this shift, and to remain attentive to the silences and deletions, to what happens in the interstice, at transitionary moments of ‘betweenness.’ I ask that readers consider the 1979 Bienal as an instance of an interstice where the occluded and silenced ghost of modernist artist Leonard Tshehla Mohapi Matsoso, who represented South Africa at the 1973 edition of the Bienal, garnering a substantial award for his work in drawing, resides. Matsoso was the first and only Black South African artist to receive this accolade. This thesis posits that Matsoso’s absence from the exhibition in 1979, an exhibition where he would rightly have featured, constitutes a curatorial haunting, wedged in the archive of the Bienal’s history, and an opportunity for revision and evaluation of commissioning vis-àvis curating. In reading the exhibition histories’ archive “along the grain” (Stoler 2002), the commissioner emerges as a man of letters, a privileged social category found in the archive; a colonial authority whose status was founded as much on his display of European learning as on his studied ignorance of local knowledge; an implementer of the taxonomic state and modernist art historical canon (in the case of Werth); a cultivator of the fine arts of deference, dissemblance and persuasion. At a later stage and moment of dissonance and disruption, the independent curator emerges to reconsider, question and expand the canon, distancing him/herself from the (South African) State to serve the artist or artists and a wider community. This research aims to contribute, albeit in a small way, to a reappraisal of the position of Leonard Tshehla Mohapi Matsoso in South African modernism, and the distinction between commissioning and curating. , Thesis (PhD)--Rhodes University, Faculty of Humanities, Department of Fine Art, 2021
- Full Text:
- Date Issued: 2021-04
- Authors: Dantas, Nancy Isabel
- Date: 2021-04
- Subjects: Bienal Internacional de São Paulo , Curatorship , Art -- Commissioning , Art -- Political aspects , Matsoso, Leonard Tshehla Mohapi
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/174492 , vital:42482 , https://doi.org/10.21504/10962/174492
- Description: This thesis explores the distinction between commissioning and curating, adopting the Bienal de São Paulo (or Bienal) as its conceptual propeller and point of departure. The thesis regards exhibitions as palimpsests, in other words, platforms built on previous conscious or sublimated models, beyond the Venetian model inaugurated in 1895. By looking at world expositions, particularly the Cape presence at the Colonial and Indian Exhibition of 1886, this project traces a lineage of commissioners, from Sir Henry Cole to Sydney Cowper through to the Director of the Pretoria Art Museum, Albert Werth. It distinguishes these men, their vision and allegiances from the curatorial model instantiated in South Africa by the late Okwui Enwezor as a consequence of the Second Johannesburg Biennale, held in 1997. The aim of this research has been to provide a partial but crucial account of this shift, and to remain attentive to the silences and deletions, to what happens in the interstice, at transitionary moments of ‘betweenness.’ I ask that readers consider the 1979 Bienal as an instance of an interstice where the occluded and silenced ghost of modernist artist Leonard Tshehla Mohapi Matsoso, who represented South Africa at the 1973 edition of the Bienal, garnering a substantial award for his work in drawing, resides. Matsoso was the first and only Black South African artist to receive this accolade. This thesis posits that Matsoso’s absence from the exhibition in 1979, an exhibition where he would rightly have featured, constitutes a curatorial haunting, wedged in the archive of the Bienal’s history, and an opportunity for revision and evaluation of commissioning vis-àvis curating. In reading the exhibition histories’ archive “along the grain” (Stoler 2002), the commissioner emerges as a man of letters, a privileged social category found in the archive; a colonial authority whose status was founded as much on his display of European learning as on his studied ignorance of local knowledge; an implementer of the taxonomic state and modernist art historical canon (in the case of Werth); a cultivator of the fine arts of deference, dissemblance and persuasion. At a later stage and moment of dissonance and disruption, the independent curator emerges to reconsider, question and expand the canon, distancing him/herself from the (South African) State to serve the artist or artists and a wider community. This research aims to contribute, albeit in a small way, to a reappraisal of the position of Leonard Tshehla Mohapi Matsoso in South African modernism, and the distinction between commissioning and curating. , Thesis (PhD)--Rhodes University, Faculty of Humanities, Department of Fine Art, 2021
- Full Text:
- Date Issued: 2021-04
An investigation into the application of Distributed Endpoint Processing to 3D Immersive Audio Rendering
- Authors: Devonport, Robin Sean
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/163258 , vital:41022
- Description: Thesis (MSc)--Rhodes University, Faculty of Science, Computer Science, 2020.
- Full Text:
- Date Issued: 2020
- Authors: Devonport, Robin Sean
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , MSc
- Identifier: http://hdl.handle.net/10962/163258 , vital:41022
- Description: Thesis (MSc)--Rhodes University, Faculty of Science, Computer Science, 2020.
- Full Text:
- Date Issued: 2020