Exploring grade 11 learners’ mathematical problem-solving skills using Polka’s model during the learning of Euclidean geometry
- Authors: Hlupeni, Ratham
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/436465 , vital:73274
- Description: The skill of Problem-solving in Mathematics is very imperative. Poor performance by most South African learners in schools and international tests such as the Trends in International Mathematics and Science, calls for emphasis to be placed on problem-solving in the teaching and learning of Mathematics. Euclidean Geometry is perceived, especially by learners, to be one of the difficult components of Mathematics. Thus, the aim of this study was to explore and develop the mathematical problem-solving and geometric skills of Grade 11 learners in Euclidean Geometry. Polya’s model of problem-solving was employed in geometric skills development as a tool for intervention. The concepts Geometry and problem-solving formed the conceptual framework of the study, while the social cognitive theory constituted the theoretical framework. A case study was used as the main research method following a mixed method approach within an interpretivist paradigm. Purposive and convenience sampling methods were used in the selection of both the Mathematics class and the six learners whose work was further observed and analysed. Data about the geometric skills displayed by the learners was gathered using a moderated pre-intervention test; observations; document analysis; a moderated post-intervention test; and focus group interviews. Data was analysed quantitatively using descriptive statistics and qualitatively using thematic analysis. In the pre-intervention test, learners did not bring with them expected geometric skills to the classroom before they were introduced to grade11 Geometry content and when doing problem-solving during intervention, the four stages of model used were not necessarily following each other in a linear sequence with most of the learners not applying the fourth stage “look back”. In the post intervention test, the frequency of use and application of most geometric skills improved in comparison to the pre-intervention test; the frequency of correct and inappropriate application of the skills increased at the expense of incorrect application. Learners appreciated the four stages model and gave their views related to the challenged faced during the use of the four stages model and the challenges revealed include: practice related challenges, challenges specific to certain learners, concept related challenges, curriculum-related challenges, model application challenge, and context related challenges. The study concludes that the effective use of Polyas’ four stages model can yield great results in developing learners’ geometric and problem-solving skills. The study recommends that teachers give more attention to prior geometric knowledge, teaching of geometric theorems, teaching of geometric problem-solving, and the learning environment. , Thesis (MEd) -- Faculty of Education, Secondary and Post School Education, 2024
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Insights: elucidation of squalene monooxygenase inhibitors for lowering cholesterol in cardiovascular diseases
- Authors: Leoma, Mofeli Benedict
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434861 , vital:73111
- Description: Statins have been used to lower high cholesterol levels in the past few decades. However, several studies have shown that some people taking statins experience side effects over time, especially elderly patients, women of childbirth possibility, and children. Several studies have shown that the majority of people with underlying cardiovascular complications caused by high cholesterol are at a greater risk of fatality due to COVID-19, regardless of age and sex. The literature suggests that antimycotic squalene monooxygenase inhibitors, terbinafine and its derivatives, and anticholesterolemic squalene monooxygenase (SM) inhibitors could be another option and a safer remedy for lowering cholesterol in mammals. Molecular docking calculations, molecular dynamics (MD) simulations, molecular mechanics generalized born surface area (MM-GBSA) calculations, quantum mechanics/molecular mechanics calculations (QM/MM), and density functional theory (DFT) calculations were used in this study. An early stage in drug discovery, in which small molecular hits from high- throughput screening (HTS) are evaluated and undergo limited optimization to identify promising lead compounds, is referred to as lead generation. To address the first step of lead generation, the number of compounds to be tested was narrowed down, and the hit compounds that could be taken for further tests were obtained. Thus, the molecular docking technique was taken advantage of, which assisted us in identifying the antimycotic ligand SDZ 18, which had a good binding affinity of about -8,4 kcal mol−1. Another widely employed strategy, the molecular mechanics-generalized born surface area (MM-GBSA), was used to investigate the binding free energies of the protein-ligand complexes to validate the binding affinities obtained from molecular docking. Despite the excellent docking results, it must be emphasized that the stability of the ligand in the binding pocket must be investigated. To address this, the protein-ligand complexes were then taken through molecular dynamics for 100 ns simulations calculations which showed that the inhibitors stayed in the binding pocket with the RMSD values below 3.5 Å for most systems. This provided insight into a realistic model because the docked complexes were placed in conditions closer to the physiological environment at 300 K and 1.01325 bar, and in an explicitly solvated dynamic environment. Density functional theory (DFT) at the B3LPY level of theory using the standard 6-31G(d,p) basis set was used to assess the reactivity and other properties of the SM inhibitors. ONIOM calculations were performed to explain what was happening at the microscopic level by calculating the total energy of the complex. The aim of this project was to efficiently uncover the non-physical aspects of SM inhibitors with the help of computational techniques to identify new drugs that can lower high cholesterol levels. From a theoretical perspective, the results obtained from docking indicated that the antimycotic ligands SDZ SBA 586 18 and TNSA 84 (trisnor-squalene alcohol ) have good binding affinities, and the MM-GBSA method provided free energy calculations. MD results indicated that the stability of the ligand in the binding pocket was achieved during the 100 ns simulations. The HOMO-LUMO energy gaps obtained from DFT calculations provided information on the reactivity of the ligands. Other insights into the protein-ligand complexes were obtained from a hybrid ONIOM QM/MM study. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
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Investigating playing-related musculoskeletal disorders in South African instrumental musicians
- Authors: Green, Erryn Mae
- Date: 2024-04-04
- Subjects: Musculoskeletal disorder , Musculoskeletal system Diseases , Musicians Wounds and injuries , Musicians Health and hygiene , Human engineering South Africa , Musicians Health risk assessment , Biomechanics , Musical instruments , Music genre
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435310 , vital:73146
- Description: This study, one of the first studies in SA to investigate PRMD in a wideranging sample of instrumental musicians using a validated self-report tool, shows that PRMDs are highly prevalent among a range of SA musicians and have a considerably negative effect on musicians’ performance ability and quality of life. However, making inferences about most affected genre or instrumental group was challenging due to the small sample sizes in some categories. The results from this study confirm that the nature of PRMD development is indeed multi-factorial, with factors numerous individual and playing-related factors playing a role in the development of PRMDs in SA musicians. Better support and education on health promotion for musicians, including awareness of and prevention strategies for PRMDs in the SA context are needed which may reduce the prevalence of PRMDs. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2024
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Perceptions of registered counselors’ ability to process clients’ narrated dreams during counselling
- Authors: Mpondo, Nontutuzelo
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435468 , vital:73160
- Description: Research related to South African registered counsellors (RCs) have yet to show how RCs incorporate dreamwork in their counselling sessions. Dreamwork has largely been relegated to the periphery of clinical psychological practice, posing a challenge as clients on other levels of counselling practice bring dream material to mental health practitioners often lacking confidence and competence to respond effectively to this material. Clients' discussion of dreams can be beneficial in the counselling process. However, there appears to be a gap in educational opportunities for practitioners to develop skills and competency in working with dreams. This study's objective was to contribute to the sparse research material in this area. A qualitative research approach with an exploratory design using semi-structured interviews was used to explore and understand the meaning RCs ascribed to their work with dreams and clients. Purposive sampling was used to recruit 5 participants. Social constructionism was used as a theoretical framework for understanding and interpreting the data, and the data was analysed using thematic analysis. This knowledge is geared towards providing insight into what extent university or college curriculum covered content related to dreams, dreamwork, dream theories, and dream models, and to what extent RC's training prepared them to provide essential primary psychological services related to distress arising from dreams. This research highlighted how RCs engaged and perceived their competency with dream material. This study also highlighted that RCs were interested in dreamwork training and believed it would enhance their confidence and effectiveness in working with dream material during their sessions. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
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Towards a possible future solution against Multidrug Resistance: An in silico exploration of the Multidrug and Toxic compound Extrusion (MATE) transporter proteins as potential antimicrobial drug targets
- Authors: Damji, Amira Mahamood
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435009 , vital:73123
- Description: The rise of multidrug resistance (MDR) has become a pressing global issue, hindering the treatment of cancers and infectious diseases, and imposing a burden on healthcare systems and the economy. The Multidrug and Toxic compound Extrusion (MATE) superfamily of membrane efflux transporters is one of the key players contributing to MDR due to their ability to export a wide range of cationic and hydrophilic xenobiotics, including treatment drugs, from cells, diminishing their efficacy. Targeting MATE transporters holds great promise in achieving some cellular control over MDR, but first, a deeper understanding of their structure-function-dynamics link is required. This study aimed to explore the MATE transporters as potential antimicrobial drug targets using a two-fold in silico approach. First, virtual screening of compounds from the South African Natural Compounds Database (SANCDB) was performed to identify prospective lead inhibitory compounds against the MATE transporters using molecular docking, and top hits were selected based on their binding energy and interaction with the active site on the N-lobe of the protein. Second, to investigate the molecular-level dynamics of their extrusion mechanism, the MATE transporter structures were embedded in a POPC membrane bilayer using the CHARMM-GUI online tool and then subjected to MD simulations for 100 ns with the CHARMM 36m force field using GROMACS. The resulting trajectories were evaluated using three standard metrics – RMSD, RMSF, and Rg; significant global structural changes were observed and key functional regions in both membrane- and non-membrane transmembrane (TM) segments were identified, containing more dynamic and flexible residues than other regions. Furthermore, the MATE transporters showed more of a loosely-packed structure, providing flexibility to allow for conformational switching during their substrate-transport cycle, which is typical for proteins whose secondary structures are composed of all α-helices. The scope of this study lied in the preliminary stages of the computer-aided drug design process, and provided insights that can be used to guide the development of strategies aimed at regulating or inhibiting the function of the MATE transporters, offering a possible future solution to the growing challenge of MDR. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2024
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Medication adherence: a review of policy and education in South Africa
- Authors: Nyoni, Cynthia Nomagugu
- Date: 2023-10-31
- Subjects: Patient compliance South Africa , Drugs Administration Study and teaching (Higher) , Pharmacist and patient South Africa , Pharmaceutical policy South Africa , Patient education South Africa , Medication adherence
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/419548 , vital:71653
- Description: Medication adherence is a patient's active and voluntary participation in following all the recommendations and instructions agreed upon with a health care provider such as a pharmacist. Adherence is a multidimensional phenomenon determined by the interplay of five factors: patient-related factors, socioeconomic factors, condition-related factors, health system-related factors, and therapy-related factors. Medication non-adherence is a problem in many countries, especially low to middle-income countries, including South Africa (SA). In low to middle-income countries, non-adherence is often worse due to insufficient health resources and inequities in access to health care. Medication adherence is a global problem and has raised the need for research and review. Many healthcare professionals, especially pharmacists, have an essential role in promoting medication adherence. This study described, explained and evaluated the policies in SA relating to the pharmacist's role in promoting medication adherence. Furthermore, it described medication adherence-related education at four universities in South Africa. The study was qualitative, and a two-phased approach was employed. In the first phase, a document analysis of the pharmacist’s role in supporting medication adherence was conducted as described in national policies and guidelines in SA. A total of 38 documents were analysed, including critical documents such as the South African Pharmacy Council Good Pharmacy Practice Manual and Associated SAPC rules (GPP) manual, National Drug Policy (NDP), Standard treatment guidelines (STGS) and Integrated Adherence Guidelines. The READ approach was used in conducting the document analysis and involved (1) preparing materials, (2) extracting data, (3) analysing data, and (4) distilling findings. The critical roles of pharmacists in medication adherence that were identified were in drug use, supply and management, dispensing, therapeutic drug monitoring, pharmacovigilance, pharmaceutical care, and special programmes like antimicrobial stewardship (AMS), multi-drug resistant tuberculosis (MDR-TB) care and antiretroviral treatment (ARV) and chronic conditions. In the second phase, in-depth interviews were conducted with lecturers to investigate and report on the inclusion of medication adherence and the teaching thereof in the curriculum of the Bachelor of Pharmacy Degree (BPharm) in pharmacy institutions in SA. Purposive sampling was used, and seven lecturers from four different institutions participated in the interviews. The interviews were conducted via Zoom® and were transcribed and analysed using thematic analysis. The teaching of medication adherence in the BPharm curriculum of the respective interviewed pharmacy institutions was explored. It was found that the topic of medication adherence was integrated into all subjects throughout the curriculum and not taught as a formal course. Although medication adherence is taught in many disciplines, it is predominantly in pharmacy practice in all institutions. The teaching methods identified included lectures, case studies, workshops, tutorials, practicals, readings, tasks, assignments and videos. The perceived effectiveness of the teaching methods was explored; also the time spent teaching medication adherence and the time efficiency. Student understanding, interest and engagement with the topic were explored and determined through their assessment performance and class attendance. In conclusion, from policies, the pharmacist's role concerning adherence is indirectly integrated into many other roles. It is often not distinguishable from that of other healthcare professionals and is often implied as part of a more generic role. Pharmacy students are educated on medication adherence and the skills and knowledge required to identify, monitor and support patient adherence to therapy. However, there is scope to increase the course content on medication adherence. There is a need to identify effective strategies for preparing pharmacists to assist patients in medication adherence. , Thesis (MPharm) -- Faculty of Pharmacy, 2023
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A study on visual inspection of citrus sorters in a packhouse in the Eastern Cape of South Africa
- Authors: Maher, Christopher Richard
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424256 , vital:72137
- Description: Background and Purpose. The South African citrus industry is a major global producer of citrus as well as the second largest exporter of citrus fruit in the world. This industry provides employment to an estimated 112 000 workers in South Africa and is vital in providing economic opportunities to communities such as those in the Sunday’s River Valley in the Eastern Cape province of South Africa due to the low employment and education levels within this province. Citrus sorting is a visual inspection task that requires workers to sustain attention and remain vigilant for the duration of a working shift. Their role in the packhouse is to ensure that no defective products are packed for export or the local market and that the fruit meets the customers’ expectations. Since the demands of sorting citrus are poorly understood, this study attempted to assess the effect that sorting citrus has on vigilance performance as well as attempt to quantify perceived workload while taking into account different contextual factors that affect perceptions of this working task. Methods. This study was conducted within a citrus packhouse in the Eastern Cape province of South Africa. The sample was comprised of individuals employed by the packhouse as citrus sorters. In addition to a recruitment and information session, testing was conducted at three intervals during a working shift on four consecutive days. Each time, indicators of vigilance, such as correct responses, sensitivity, reaction time, false alarms and misses, were collected during a 5-minute computerised version of the Mackworth Clock-test, while perceived workload was assessed with the NASA-TLX scale, and sleepiness was recording using the WITS Sleepiness Scale. Furthermore, an open-ended question was asked to further understand factors affecting the ability of participants to concentrate during their task of sorting. Results. 18 participants consented to participate in this study. 16 of these individuals identified as female with an average age of 30 years (± 7). 83% of participants were of Black African descent and were isiXhosa speakers, while 17% of participants were of Coloured descent and Afrikaans speakers. This study found that performance, as measured by the percentage of correct responses, sensitivity and reaction time on the 5-minute long Mackworth Clock Test was not significantly affected as time-on-task for sorting citrus increased during a working shift, neither did performance on the vigilance test change as days of the week proceeded. However, ‘misses’ during the vigilance test were found to significantly decrease over the course of a working shift, thus contradicting the expected outcomes of this study. Perceived workload of sorting citrus, as well as perceived sleepiness, significantly increased with time-on-task during the course of a working shift. The major contributions for this increase in perceived workload while sorting citrus were derived from the Mental Demand and Physical Demand sub-scale for the NASA-TLX. However, responses from the open-ended question indicated that participants generally enjoyed their work, although there were factors, such as the nature of fruit and social set-up of work, that negatively affected this perception. Discussion. The results from this study contradicted the researcher’s expectations. It was anticipated that measures of correct responses and sensitivity would decrease and misses, and reaction time would increase with time-on-task for sorting citrus, yet vigilance indicators from the Mackworth Clock Test generally indicated no change in vigilance, and, according to “misses” even improved with time-on-task. A likely explanation for this is that the use of a 5-minute Mackworth Clock-test was unsuitable in this context, or rather, the time of this test was not long enough to induce a ‘vigilance decrement’. Furthermore, in order to administer this vigilance test, participants were taken off the production line and led to a testing room which most likely increased their levels of arousal, thus affecting performance on the vigilance test. However, even though perceived sleepiness was found to significantly increase over the course of a working shift, these data correlated poorly with the vigilance results, thus contradicting the expected outcomes of the study. Mental demand significantly increased, possibly due to the demand of attentional informational processing required for sorting, as well as various environmental factors present within the packhouse. Physical demand, too, significantly increased as workers were required to remain standing throughout their working task as well as to make use of their upper extremities to remove defective fruit. Correlation analyses showed significantly weak correlation for Mackworth Clock Test variables and sleepiness ratings to all other variables. NASA-TLX variables, however, generally showed significantly moderate correlations with one another. Conclusion. It remains unclear how vigilance changes and sustained attention while sorting citrus, since the experiment did not show changes in performance. This is largely attributed to the methodological set-up which could have increased arousal and therefore affected vigilance. It is recommended that future studies research vigilance and sustained attention during the sorting itself, rather than attempting to infer vigilance results from a computerised vigilance test. Perceived workload of sorting, however, increased over the course of a working shift due to significant increases in perceptions of the physical and mental demands of sorting. Future studies should address concerns relating to the physical demand of sorting. Furthermore, it would be beneficial to compare responses of day and night shift sorters to further understand how the relationship between these variables may change. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2023
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An investigation into fatigue prevalence amongst citrus packhouse sorters in the Eastern Cape province of South Africa
- Authors: Robinson, Harry Jack
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424312 , vital:72142
- Description: Background: South Africa is the second most influential exporter of citrus fruits internationally and holds a pivotal role in economic revenue for the country. Rural areas, such as the Sundays River Valley in the Eastern Cape province of South Africa, contribute to the country’s citrus production. Many women depend on citrus packhouses for employment as citrus sorters. As humans perceive certain defects in citrus fruits more accurately than machines, these sorters must identify and manually remove any fruit that does not conform with export requirements. Citrus sorters are exposed to numerous physical and cognitive stressors during the task while faced with organizational challenges, such as shift work and long working hours. Therefore, the potential for fatigue development is anticipated. Given the multifactorial nature of fatigue and the negative consequences it may have on workers, it also has the potential to impede the accuracy of the sorting performance. Stringent disciplinary action for the entire South African citrus industry may be of consequence if nonconforming or pest-infested fruit is missed by citrus sorters and exported to foreign countries. This study aimed to investigate the prevalence of fatigue among citrus sorters in a citrus packhouse in the Sundays River Valley of the Eastern Cape throughout a citrus harvesting season and to identify factors that may contribute towards fatigue development. Methods: The research design utilized a crosssectional, two-part approach that applied mixed methods. Part one was administered once-off, incorporating demographic, work-, and non-work-related questions. Part two was a self-developed repeated measures assessment comprising close-ended contextual questions, the Modified Fatigue Impact Scale, and the Karolinska Sleepiness Scale. Environmental and work output data were also recorded. Results: Citrus sorters (n= 35) recorded a mean MFIS score of 39.35 throughout the harvest season, which was above the prescribed fatigue threshold (38). However, there was no significant difference in fatigue ratings over time (p= 0.122). Day shift workers exceeded the fatigue threshold for the entire season compared to night shift workers, who only exceeded it in the last two weeks. The physical, cognitive, and psychosocial subscales found no significant difference in fatigue scores, although physical fatigue recorded the highest scores across all weeks and displayed a significant difference over time. Overall, participants, on average, perceived to be “neither sleepy nor alert” over the season. However, eight participants (22%) recorded sleepiness scores ii exceeding the excessive sleepiness threshold of seven. Educational levels, health status, work-pace, and the number of family dependents significantly contributed to fatigue development, albeit a weak correlation. Discussion: Sorters were perceived to be fatigued from week three till the end of the study; however, there was no variation in fatigue scores over time. An accumulation of physical fatigue over time was revealed where prolonged standing, repetitive work, and irregular working postures may have contributed. Night shift workers did not receive the recommended hours of sleep (7-8 hours); hence, they registered greater sleepiness scores over the season than day shift workers. Environmental and work output recordings did not prove to have a significant influence on fatigue development, and neither did work experience or physical exercise. Conclusion: An amalgamation of numerous contributing factors within the work situation, private situation, and the individual influenced the development of fatigue, where there was no primary causal factor. Future studies should consider recording the accuracy of the sorting performance to acquire rich, objective data. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2023
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Application of web design techniques and best practices in implementing web development, maintenance and enhancement of RUBi websites and web application systems
- Authors: Tshabalalala, Thulani
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424688 , vital:72175
- Description: The popularity of the web has seen various fields, such as the sciences taking advantage of this resource to further their scientific endeavours. This has seen science groups moving into developing websites and web applications, and such a group is the Research Unit in Bioinformative (RUBi). With the use of the web, the development and maintenance of whatever web-related tools become inevitable, given the continuous changes in the web space. This continuous evolution of web development and maintenance will come with techniques, principles and standards which will not only enable faster development of web entities but also ensure that modern hardware, fulfilment of the requirements to use such hardware and modern concepts are incorporated into forming web tools that enable such progression. Furthermore, introducing the previously mentioned progress of the web becomes an essential part of its development and maintenance. This paper did implement the processes of progressing the web using the technique of documentation and version control systems. The web development for the COVIDRUG website was done for the Covidrug-Africa Consortium (COVIDRUG) using the Django webdevelopment framework. The RUBi website and the MDM-Task we band the Job Management System (JMS) web applications were maintained for the maintenance aspect. Archives brought value regarding the traceability it provides of the various web-related aspects. The development showed a website’s potential value, particularly for research groups. The maintenance carried out showed how different techniques and approaches could be used in different maintenance prospects to achieve set objectives. The development and maintenance resulted in websites and web applications that have the features stated in their respective maintenance plans. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2023
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Applying human factors and ergonomics system analysis methods to the V5-NRS Cessna 441 Conquest II aviation accident
- Authors: Fischer, Jordan Daena
- Date: 2023-10-13
- Subjects: Ergonomics , Human engineering , Accident investigation , Aircraft accidents Investigation , AcciMap Approach , System theory , Study of complex systems
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424245 , vital:72136
- Description: Intro: Accidents are complex in nature with multiple contributing factors. The way in which accidents are investigated is important and using system-based analysis tools assists in understanding and mapping these contributing factors to learn from them. There has been an increase in the number of accidents that have occurred within the general aviation industry in South Africa and while accident investigations have been undertaken, these have not included the application of system-based analysis tools. This led to a collaboration between Rhodes University and the Accident and Incident Investigations Division (AIID) of the South African Civil Aviation Authority where it was agreed that two systems-based analysis tools will be applied to a previously investigated accident that occurred in 2015. Aims: The first aim of this thesis was to identify if, through the implementation of these systems-based tools, the systemic contributory factors could be determined using the existing report by the AIID. The second aim of this thesis was to identify if, using the two systems-based tools, the actors and levels involved in the accident could be identified and the third aim was to identify if the implementation of these tools generates the same or different recommendations to that of the AIID. Methods: The two systems-based analysis tools applied were AcciMap and Causal Analysis using Systems Theory (CAST). These tools were applied to the V5-NRS Cessna 441 Conquest II accident report which captured the details of how the aircraft flew into the Tygerberg mountain on its descent into the Cape Town International Airport in August 2015. Results: Through the application of these two systems-based analysis tools the major contributing factors elucidated throughout this analysis were: visual and lighting conditions, pilot experience, training, lack of terrain warning equipment, fatigue, inadequate oversight, and inadequate risk management. In line with these findings, the analysis revealed various actors across various levels (the crew; South African Air Traffic Control, the SACAA, WestAir (the operator) and the Namibian Civil Aviation Authority Through the elucidation of these factors at various levels, 14 to 15 different recommendations were generated which was more than the one recommendation that was generated by the AIID. Discussion: Even when applied to an existing report, both the CAST and Accimap tools were able to bring to light the systemic contributing factors to this accident and importantly, highlight the role that various actors and levels within the system had in this unfortunate event. Consistent with previous literature, most of the contributing factors were found at the lowest level (the crew in this case) and fewer, but key factors were identified at higher levels (management and regulator level). Importantly, the application of the systems tools facilitated a systematic and systemic analysis of this accident, which allowed for the generation of recommendations at all levels, not just at the operator level. Conclusion: This study demonstrates the benefits and importance behind implementing a systems-based analysis method to an accident as these tools generate more useful recommendations which allows for important lessons to be learned following accidents, with the intention of re-designing systems to prevent them from happening again. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2023
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Associations between contraceptive use, physical activity, depression, and quality of life among women of childbearing age in Akure South Local Government area of Ondo State, Nigeria
- Authors: Alimi, Olabisi Ganiyat
- Date: 2023-10-13
- Subjects: Exercise for women Nigeria Ondo State , Depression in women Nigeria Ondo State , Well-being Nigeria Ondo State , Quality of life Nigeria Ondo State , Contraception Side effects
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424210 , vital:72133
- Description: Background: Population experts and policymakers are concerned about Nigeria's rapid annual population growth due to the country's high birth rate which was 5.3 births per woman in 2018. Fear of the side effects of modern contraceptives among Nigerian women contributes to the low rate of contraceptive use, which was reported to be 17% and 37% among married and sexually active unmarried women, respectively. Which is a significant cause of the high birth rate. Although the side effects of modern contraceptives on women's clinical and physiological variables are well known, studies examining the associations between contraceptive use and physical and psychosocial variables such as physical activity (PA), depression, and quality of life (QoL) in non-athletic Nigerian women of reproductive age are scarce. This study aimed to examine the associations between contraceptive use, PA, depression, and QoL among non-athletic women of childbearing age in Akure South Local Government, Ondo State, Nigeria. Methods: In a descriptive cross-sectional study, 646 women of childbearing age were recruited using the multistage sampling technique. The data of 496 current contraceptive users and 146 non-users were analysed, as 4 respondents did not respond regarding current contraceptive use status. The Global PA Questionnaire (GPAQ), Beck’s Depression Inventory (BDI) and World Health QoL Organization Quality of Life Brief (WHOQoL BREF) were used to assess respondents’ scores/levels of PA, depression and health-related quality of life (HRQoL). The GPAQ, BDI, and WHOQOL scores were compared between contraceptive users and non-users using non-parametric Quade Analysis of Covariance while age, married status, tribe, religion, and occupation were included covariates. PA, sedentary behaviour (SB), and BDI scores were categorized using guidelines. Contraceptive use/practice was the outcome variable. Pearson's chi-square test bivariate analysis and a multivariate logistic model were used to identify factors associated with contraceptive use (users and non-users). Crude and adjusted odds ratios and their confidence intervals were calculated to determine the significance of the association. The regression model was adjusted for age, marital status, religion, tribe, highest education level, occupation, awareness of contraceptives, current use, lifetime use, type, class, and duration of current contraception. “Statistical significance was set at p < 0.05. Results: The mean age of the respondents was 29.73±6.10 years. The contraceptive users and non-users were not significantly different regarding their ages (p = 0.135), marital status (p = 0.245), highest education (p = 0.444), occupation (p = 0.238), and tribe (p = 0.192). The respondents’ lifetime and point prevalence of contraceptive uptake was 93.6% and 77.3%, respectively, while 72 (12.8%) reported experiencing contraception-related side effects. Of the 496 respondents who currently practice contraception, 146 (29.4%) were hormonal contraceptive users. The majority of the respondents had moderate and mild levels of PA (48.5%) and depression (51.4%), respectively, and a significantly higher proportion of contraceptive users had minimal and moderate depression levels than the non-users (p = 0.018). The contraceptive users demonstrated significantly higher median scores of BDI (p = 0.02), Physical health QoL (p < 0.001), environment QoL (p = 0.033) and overall QoL (0.004) than the non-users. Hormonal contraceptive users had significantly higher median PA walking/bicycling scores than non-hormonal users (p = 0.014). Respondents with mild and moderate depression levels had higher odds of being contraceptive users than those with minimal depression (AOR = 3.12, 95% CI = 1.43 – 6.80, p = 0.04 and 4.67, 95% CI = 1.92 – 11.36, p = 0.001 respectively). Conclusion: Contraceptive use is negatively associated with depression but positively related to Physical health, environment and overall domains of HRQoL. Healthcare professionals should consider women's mental and emotional condition while advising on family planning for optimal HRQoL. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2023
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Characterizing shift systems and exploring their effects on sleep and fatigue in South African freight railway operators
- Authors: Mona, Chumani
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424300 , vital:72141
- Description: Embargoed. Expected release date 2025. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2023
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Controls of lateral and vertical variations in the geochemistry of the Hotazel Fe-Mn Formation at Nchwaning and Gloria mines, Kalahari Manganese Field, South Africa
- Authors: Dorbor Jr., Stephen Baysah
- Date: 2023-10-13
- Subjects: Manganese ores Geology South Africa , Iron ores Geology South Africa , Geochemistry Geology South Africa , Kalahari manganese field , Banded iron formation , Hotazel mine
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424621 , vital:72169
- Description: The Paleoproterozoic Kalahari manganese field (KMF) in the Northern Cape Province, South Africa, hosts a large resource of manganese ores that has been of great interest over many decades. The Kalahari Manganese deposit (KMD), which is the largest of five erosional relics of the Hotazel Formation in the KMF, hosts three beds of Mn ores with alternating layers of banded iron formation (BIF) and hematite lutite. These three rock types are all evaluated for their mineralogy and geochemistry in this study, with emphasis on lateral and vertical distributions across the Gloria and Nchwaning Mines in the northernmost KMF, an area of high-grade, hydrothermally altered Mn mineralisation. The Mn ores of the Hotazel formation are traditionally categorised into two types. The carbonate-rich low Mn grade (Mn≤40 wt. %) ores (Mamatwan-type) domninates the largest part of the KMD, while carbonate-free, high Mn grade (Mn≥ 45 wt.%) ore (Wessels-type) occurs in the northernmost KMD. The Wessels-type ores are considered as the hydrothermally altered product of Mamatwan-type ores, and as indicated above, are the focus of this study. Five drill cores containing Wessels-type ores from the Nchwaning and Gloria area of the northern KMD were analysed to help understand the petrographic and particularly the geochemical variations in the Hotazel Fe-Mn Formation, both laterally for a given Mn layer of the three, and vertically across Mn layers as captured in specific drillcores. Petrographic and whole-rock geochemical results obtained from the three rock types of the Hotazel Formation show variations in their mineralogical and geochemical compositions, especially in the high-grade Mn ores themselves. Most of the samples of the BIFs layers are dominated by hematite and chert occurring in banded fashion, which is typical of a normal carbonate-free altered BIF discussed in this thesis. The BIFs can also be locally enriched in hematite (ferruginised), occurring as massive hematite ores usually at the top of the stratigraphic profiles. The presence of aegirine-rich assemblages is also noted occurring in some of the BIF and hematite lutite sections immediately above and below the Mn ore beds. The high-grade Mn ore beds vary greatly in mineralogy and texture of the ores laterally and even within a single drill core. In an extreme case, a single drillcore sampled from the Gloria mine (GL57) contains high-grade Wessels-type ore in the upper Mn bed and low-grade, Mamatwan-type ore in the lower Mn layer. Geochemically, the Mn ore bodies also show substantial geochemical variability, although a net increase in the Mn grade downward is usually characterised by a corresponding depletion in mainly bulk Ca, Si and carbonate. However, the Fe content appears to be consistently higher in the upper ore bodies of the drillcores than the lower ones, and the increase in the concentration of the Fe-oxide expectedly causes a relative decrease in the bulk Mn-oxide concentration, usually expressed as an antithetic relationship between the two elements. In terms of trace element distributions, this appears to be more significant in the Mn ores than the other two rock types affected by the same alteration process, probably due to the presence of Mn phases such as hausmannite and braunite serving as good hosts to several trace elements. Cu, Zn, Pb and to a lesser extent Mo are trace metals that appear to show elevated concentration levels (net enrichments) in high-grade Mn ore by comparison to the presumed Mamatwan-type protolith. Ba is an additional element of clear enrichment, manifested mainly as the mineral barite. The Northern KMD has a complex post-depositional history, which includes the intrusion of NE-SW-trending dykes, formation of the Mapedi/Gamagara erosional unconformity, normal faulting associated with the Wessels event and major thrust faults in the western part of the northern KMD. These structural events all have the potential to have contributed to the alteration and subsequent enrichment of the Mn ores in the Nchwaning and Gloria area. As such, the mineralogical, textural, and geochemical variations observed here can tentatively be attributed to the different structural features in the northern KMD. Classic interpretations suggest that normal N-S-trending fault structures have acted as fluid conduits for hydrothermal fluids, which led to the metasomatic alteration of the Mn ore body laterally. Drill cores proximal to and evidently affected by fault-controlled alteration in the SE and SW-portions of the Nchwaning area, have comparable mineralogical and geochemical characteristics for both ore bodies (upper and lower) with subdued alteration effects from the unconformed contact above. Fluids associated with the Mapedi/Gamagara unconformity, would have percolated down-stratigraphy causing oxidative ferruginisation, which led to the formation of massive hematite ores in the top BIF layers and ferruginised Mn ores in the Mn ore beds. This alteration effect appears more prominent in a drill core from the northern part of the study area where the unconformity contact appears more proximal to the upper Mn bed. Drill cores located in the western part of the Nchwaning area seem to also capture evidence of fluid alteration with enrichment in Na recorded in the local abundance of the mineral aegirine. Finally, the dyke structures appear to have acted as impermeable fluid barriers to both lateral and possibly down-dip fluid-flow. , Thesis (MSc) -- Faculty of Science, Geology, 2023
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Development of an evidence-based framework for the prevention and management of musculoskeletal disorders in South Africa
- Authors: De Bruyn, Elrico
- Date: 2023-10-13
- Subjects: Musculoskeletal system Wounds and injuries South Africa , Musculoskeletal system Wounds and injuries Treatment , Human engineering Handbooks, manuals, etc. , Musculoskeletal system Wounds and injuries Prevention , Industrial engineering South Africa , Work environment South Africa
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424232 , vital:72135
- Description: Background: Musculoskeletal Disorders (MSDs) are multi-causal soft tissue disorders that result in disability, discomfort, and pain. MSDs are prevalent in 21.5% of the world’s population and carry a great financial and personal burden to individuals, businesses and countries alike. The multi-casual nature of MSDs has resulted in a vast amount of literature being published on how to prevent and manage the disorders, to the extent that navigating through the literature to find effective and context-specific interventions has become time-consuming and difficult. This is the case in South Africa, where ergonomists have no guide or framework to navigate MSD literature, and context-specific literature is limited. Aims: This study aimed to assist ergonomists in South Africa navigate the MSD literature to identify and select appropriate MSD prevention and management interventions. To do so, three objectives of the study were identified: 1. Review MSD literature to identify effective MSD prevention and management interventions. 2. Create a framework to act as a guide for ergonomists to navigate MSD prevention and management studies. 3. To verify the suitability of the framework in the South African context. To achieve these objectives, the study took a two-phased approach. Phase 1: A scoping review of MSD literature was conducted to identify effective MSD prevention and management approaches. Sixteen (n=16) prevention strategies and fourteen (n=14) management strategies were identified. The information from the review was analysed and grouped into five hierarchical levels of interventions (“Law”, “Organisational Policies”, “Management Systems”, Workplace Interventions”, and “Individual”). This information, along with a conceptual model created for the navigation of the literature, was used to create a draft framework for musculoskeletal disorder prevention and management. It was concluded that although there were many effective MSD interventions, there was a lack of South African-specific literature. Phase 2: Interviews with five certified ergonomists working in the South African context were conducted to verify the framework’s suitability for a South African working environment. The interviews identified two MSD prevention and three MSD management themes as effective in South Africa. Both prevention themes (“training and education” and “workplace interventions”) were also mentioned to be part of the stakeholders’ ideal MSD prevention programme, further reinforcing their usefulness. The use of “workplace interventions” was also identified to be effective in MSD management, alongside interventions at the management level and the use of alternative tools and equipment. However, the lack of managerial buy-in was identified as a barrier to MSD prevention. Stakeholders also highlighted that job specification and work hardening was an MSD strategy missing from the framework that was effective in South Africa's MSD management. The use of surveillance practices was found to be ineffective in South Africa, with lots of resistance towards it from workers. Conclusion: The framework presented in Phase 1 identified many effective MSD interventions; however, only a few were found to be applicable to the South African working context during Phase 2. Future research should focus on identifying the success of different MSD interventions in South Africa with participation from the ergonomists involved in the implementation to create an even more suitable guide that matches the South African ergonomist’s needs. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2023
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Distribution and habitat preferences of marine megafauna in Nosy Be, Madagascar
- Authors: Lubbé, Alicea
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424710 , vital:72177
- Description: Marine megafauna have important ecological roles including the top-down regulation of lower trophic levels and the transport of nutrients. They are also charismatic species of socioeconomic importance, due to their public appeal and focus for ecotourism. However, these taxa face numerous anthropogenic threats including bycatch, habitat-loss, noise disturbance, prey reductions, pollution, and vessel traffic. Northwest Madagascar has been identified as an important marine mammal area and whale shark aggregation site, yet limited information on megafauna within Madagascar exists. In this thesis, I investigated the community structure, distribution trends, related environmental factors (Chapter 2) and predicted habitat suitability (Chapter 3) using a species distribution modelling approach for marine megafauna around Nosy Be, North-west Madagascar. Data collection consisted of opportunistic boatbased surveys conducted while looking for whale sharks, mobulid rays and cetaceans. These activities were performed by dedicated ‘swim with whale shark’ tourism operators, Les Baleines Rand'eau and Safari Baleine during tourism activities directed by the Madagascar Whale Shark Project over four years (2016-2019). A total of 1792 sightings were reported with 13 identified species, including elasmobranchs: whale shark, Rhincodon typus; spinetail mobula ray, Mobula japonica; giant oceanic manta ray, Manta birostris; shortfin devil ray, Mobula kuhlii; balaenids: humpback whale, Megaptera novaeangliae; Omura's whale, Balaenoptera omurai, delphinids: Indo-Pacific bottlenose dolphin, Tursiops aduncus; spinner dolphin, Stenella longirostris; pantropical spotted dolphin, Stenella attenuata; Indian ocean humpback dolphin, Sousa plumbea; false killer whale, Pseudorca crassidens; melonheaded whale, Peponocephala electra and one cheloniid species: leatherback sea turtle, Dermochelys coriacea. Sightings were spatially analysed at a community level according to feeding guilds (i.e., filter feeders vs. predators), and distribution of the megafauna groups v were compared to selected remotely sensed physico-chemical data (sea surface temperature and chlorophyll-a concentration) and bathymetry charts (depth and slope) using generalized linear models (Chapter 2). All four variables had a significant effect on filter feeder distribution. Spatial distribution of filter feeder sightings peaked at an area of steep underwater topography (18-50m; x slope=0.5%) located on the west coast of Nosy Be, where foraging aggregations of large filter feeders (primarily R. typus and B. omurai) were frequently observed. Only SST had a significant effect on the relative abundance of animals in the predator feeding guild, which demonstrated a more longitudinal distribution along the continental shelf. The maximum entropy model (Maxent) was used for predicting habitat preference for the most frequently sighted species (Chapter 3). The distribution of whale sharks, mobulid rays and Omura’s whales were significantly overlapped as they were abundant in two main hotspots, Grand banc de l’entrée (~10 km of the west coast) and near Nosy Mitsio island, (~50 km northeast of Nosy Be). Suitable habitat for the dolphins was in relatively shallow waters in temperatures <28ºC near areas of steep changes in bathymetry. Bottlenose and spinner dolphins had a more widespread distribution across the continental shelf and humpback dolphin was closely associated with inshore reefs and occur in waters <10m. The coastal and inshore region of Nosy Be is an important habitat for a variety of megafaunal species, and the continental shelf provided essential areas for feeding and breeding. The results were similar to those presented for these species in other regions of the Indian Ocean (i.e., Eastern and Southern Africa; Western Australia; Seychelles) as well as outside of the Indian Ocean (i.e., Indonesia; Caribbean; North Atlantic). Thus the results from this thesis could be considered for management recommendations for marine conservation in the region. The value and limitations of data collected by citizen science were outlined (Chapter 4). , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
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Empty adjectives and excessive intensifiers, or savvy discourse moves? A feminist critical discourse study of gender-based differences in the discourse of businesspeople on LinkedIn
- Authors: Schmauss, Lindsay Susannah
- Date: 2023-10-13
- Subjects: Corpora (Linguistics) , Critical discourse analysis , Intensification (Linguistics) , Women's language , Adjective , Politeness (Linguistics)
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425111 , vital:72211
- Description: This Feminist Critical Discourse Analysis (FCDA) examines the use of ‘empty’ adjectives and the equative intensifier so in discourse on LinkedIn, a social network service (SNS) for businesspeople and professionals. These linguistic features soften the impact of what is said in ways that can conform with politeness norms that one should not impose a point of view but can also be negatively construed as weak, uncertain and unclear. The North American sociolinguist, Robin Tolmach Lakoff (1973, 1975, 2004), first associated these linguistic markers with a feminine register in her seminal work, Language and Women’s Place, arguing that there is a social expectation that women talk like a lady and follow politeness conventions, while the speech of men is not similarly constrained. That women are socially conditioned to speak in ways that can undermine their clarity and assertiveness would present a particular dilemma in the business context, where clear, direct and confident communication is valued. This corpus-based study explores the dilemma in the context of LinkedIn where the linguistic behaviour of cisgender women indeed showed evidence of their struggle between conflicting impulses to talk like a lady and a desire to be taken seriously as businesspeople. While the examined features mainly appeared in the discourse of women, it was interesting to note men making use of ‘empty’ adjectives and so in communication contexts where the goal appeared to be relationship-building. As notions of business leadership are evolving to value organisational leadership more, this suggests that linguistic devices that have traditionally been associated more with the communal conversation of the stereotypical ‘woman’ appear to be gaining wider acceptance and relevance, although in domains orientated towards the “soft skill” of building relationships, rather than the “hard work” of business. While the value talking like a lady may be shifting, language that is the opposite of talking like a lady seems to remain the language of serious talk, and the kind of gender-based linguistic discrimination first theorised by Lakoff seems thus to persist, also in the sphere of business discourse. , Thesis (MA) -- Faculty of Humanities, Linguistics and Applied Language Studies, 2023
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Examining teachers’ pedagogical strategies for fostering critical thinking skills in English as a Second Language (ESL) classrooms: a case study of selected Namibian secondary school teachers
- Authors: Rittmann, Heinrich Heinz
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424097 , vital:72123
- Description: Thesis embargoed. Expected release date 2025. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2023
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Exploring the strategies for teaching reading comprehension to non-readers in upper primary phase: a case study of Namibian Grade 5 ESL experienced teachers
- Authors: Mavambe, Tsitsi
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424086 , vital:72122
- Description: Thesis embargoed. Expected release date 2025. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2023
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Framing VBS: a textual analysis of Daily Maverick’s coverage of the VBS Mutual Bank heist in the years 2018-2020
- Authors: Nyulu, Siyamthanda Natascha
- Date: 2023-10-13
- Subjects: VBS Mutual Bank (South Africa) , Banks and banking Corrupt practices South Africa , Journalism, Commercial South Africa , Journalistic ethics South Africa , Frames (Sociology) , Journalism Social aspects South Africa , Daily Maverick
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425256 , vital:72223
- Description: This study investigates how Daily Maverick framed the VBS Mutual Bank scandal for its readers in the years 2018-2020. It utilises framing theory as the guiding theoretical framework in trying to understand how Daily Maverick portrayed the corruption case for its readers. This study also leans on social responsibility and normative theories of the press to analyse whether Daily Maverick fulfilled its role of facilitating dialogue between the elite and ordinary citizens of Limpopo affected by the corruption at the bank. Using a qualitative textual analysis, the thesis discusses how elite sources were quoted more than ordinary citizens who are affected the most by the corruption scandal. This allowed the elite to turn the VBS matter into a political spectacle whereas, because it is an example of failure in the financial sector, the heist caused further failures in municipalities already failing in Limpopo, North-West and Gauteng. , Thesis (MA) -- Faculty of Humanities, Journalism and Media Studies, 2023
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Halogenated Aza-BODIPY dyes for photodynamic anticancer and antimicrobial activity studies
- Authors: Magwaza, Temlandvo Matshidiso
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424514 , vital:72160
- Description: This thesis reports on the synthesis and characterisation of differently substituted aza-BODIPY dyes for use in photodynamic antimicrobial chemotherapy (PACT) and photodynamic therapy (PDT) activity studies. The aza-BODIPY dyes were synthesised by adding phenyl and naphthyl rings at the 3,5-positions of the aza-BODIPY core, with methylthiolphenyl (9a and 9b, respectively) or thien-2-yl rings (9c and 9d, respectively) at the 1,7-positions. 9a-c were iodinated at the 2-position to form 10a-c, respectively, while 9d was diiodinated at the 2,6-positions to form 10d. The methylthiolphenyl-substituted dyes (10a and 10b) were successfully conjugated to gold nanoparticles (AuNPs) to form nanoparticles conjugates (10a-AuNPs and 10b-AuNPs), while attempts to conjugate the thien-2-yl-substituted dyes were unsuccessful. The photophysicochemical properties of 9a-d, 10a-d and nanoconjugates 10a-AuNPs and 10b-AuNPs were investigated to determine their suitability for use in the applications. Adding heavy atoms such as iodine at the 2,6-positions of the aza-BODIPY led to enhanced singlet oxygen generation since these dyes displayed moderate to high singlet oxygen quantum yields. None of the dyes exhibited any fluorescence. The PACT activity studies for 9c-d, 10a-d, and the 10a-AuNPs and 10b-AuNPs were carried out against Staphylococcus aureus and Escherichia coli with a Thorlabs M660L3 light-emitting diode (LED) with an irradiance of 280 mW/cm2 for all dyes other than 10d. A Thorlabs M730L4 LED with an irradiance of 160 mW/cm2 was used for 10d. Time dependence studies were only carried out against Staphylococcus aureus, so very low log reductions were observed against Escherichia coli in initial concentration studies. The 10a-AuNP and 10b-AuNP nanoconjugates exhibited high antimicrobial activity with a log reduction of 9.41 and 0.00% viable colonies, while the iodinated aza-BODIPY had a log reduction of 8.94. The in vitro photodynamic therapy activities and dark cytotoxicity were investigated against human MCF-7 breast cancer cells for dyes 9c-d and 10c-d with a Thorlabs M660L3 LED (280 mW/cm2) for all dyes. The dark cytotoxicity was minimal in each case with IC50 > 50. Iodinated dyes 10c and 10d had IC50 values of 11.6 and 8.2 μM, respectively, and non-iodinated dyes 9c and 9d had IC50 values of 12.5 and 19.2 μM. The heavy atom effect associated with the iodine atoms increases the singlet oxygen quantum yield and enhances the suitability of the dyes for photodynamic therapy. , Thesis (MSc) -- Faculty of Science, Chemistry, 2023
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