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In vitro wound healing potential of photobiomodulation is possibly mediated by its stimulatory effect on AKT expression in adipose-derived stem cells
Get PDFAbstract: Increasing evidence suggests that adipose-derived stem cells (ADSCs) serve as a therapeutic approach for wound healing. The aim of this study was to determine the effect of photobiomodulation (PBM) on antioxidant enzymes in ADSCs. Four ADSC cell models, namely, normal, wounded, diabetic, and diabetic wounded, were irradiated with 660 nm (fluence of 5 J/cm2 and power density of 11.2 mW/cm2) or 830nm (fluence of 5 J/cm2 and power density of 10.3mW/cm2). Nonirradiated cells served as controls. Cell morphology and wound migration were determined using light microscopy. Cell viability was determined by the trypan blue exclusion assay. The enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of antioxidants (superoxide dismutase (SOD), catalase (CAT), and heme oxygenase (HMOX1)). AKT activation and FOXO1 levels were determined by immunofluorescence and western blotting. The gaps (wound) in PBM-treated wounded and diabetic wounded cell models closed faster than the controls. PBM treatment significantly increased antioxidant levels in all cell models. This reflects that oxidative stress is reduced on the counterpart of increased antioxidant levels. This might be due to the activation of the AKT signaling pathway as evidenced by the increased AKT signals via western blotting and immunofluorescence. This data suggests that PBM promotes wound healing by increasing antioxidant levels by activating AKT signaling
Experiences of Gauteng-based emergency care providers involved in critical-care transfers
Get PDFAbstract: Background: A critical-care transfer (CCT) involves the movement of a high-acuity patient from one medical facility to another by ambulance. CCTs are associated with increased stress for the emergency care provider conducting the transfer. Even though CCT forms a major component of the work of local ambulance services, the majority of local emergency medical care (EMC) education and training does not focus extensively on equipping its graduates to conduct CCTs. Internationally it is accepted that a specialised team using specialised equipment with a specially modified vehicle will conduct CCTs. The members of this team all would have completed specialised education and training before them being involved in CCTs. This is not the case in South Africa. It is commonly expected from advance life support providers, who have limited knowledge of ICU and CCTs, to conduct CCTs of high-acuity patients. At the time of this study, limited knowledge was available describing the experiences of emergency care providers conducting CCTs. It was felt important to investigate their experiences to identify possible shortcomings in the current education and training. The aim of the study was therefore to investigate, document and describe the experiences of Gauteng-based emergency care providers related to their conducting of CCTs...M.Tech. (Emergency Medical Care
A double-layer-clustering differential evolution by speciation and self-adaptive strategies for multimodal optimization
Get PDFAbstract: Multimodal optimization is to find and maintain as many global and local optima of a function as possible. Niching techniques based on multi-population and clustering have been proved to be effective and efficacious for tackling the multimodal optimization problems. How to enhance the diversity of the population and improve the global search ability of the algorithm to locate more optima is a big challenge. To address this objective, a Double-Layer-Clustering Differential Evolution (DE) based on Speciation (SDLCDE) and integrated it with Self-adaptive strategy (SSDLCDE) is proposed to solve the multimodal optimization problems. The first layer clustering based on speciation is used to divide the entire population into multiple subpopulations to locate the global and local optima. Then all the species seeds from each species form a subpopulation for the global search. To test the performance of our proposed algorithms, both SSDLCDE and SDLCDE are compared with 17 state-of-art niching algorithms on 29 multimodal problems with different dimensions. The Experiment results demonstrate that both the proposed algorithms outperform or perform comparably to the 17 niching algorithms on all the test functions
Sensitivity and specificity of computer aided detection for scoring chest X-rays compared with medical panel in Johannesburg, South Africa
Get PDFAbstract: Background: Silicosis is one of the occupational diseases which increase with the duration of exposure to silica dust that has been a major problem for ex-miners. Chest radiograph is a valuable tool for diagnosing silicosis of ex-miners. Recently, artificial intelligence Computer Aided Detection (CAD) use in chest X-ray has gained momentum in medicine for diagnosing chest pathologies...M.A. (Public Health
Symbolic representations as teachers’ reflect on Inclusive Education in South Africa
Get PDFAbstract: The inclusive education movement generated many changes in the education system worldwide, resulting in teachers needing to change their practice and beliefs and implement inclusive teaching strategies to accommodate a more diverse learner population. Numerous professional development courses were conducted in South Africa, however the expected change in attitude and practice proved difficult to achieve for many. Even after attending such courses, teachers found it challenging to establish inclusive learning environments, believing they did not have the necessary skills and resources to teach learners with divergent learning needs. This study explored the pivotal role of teachers and their personal perspectives of themselves as inclusive practitioners in South Africa after attending a professional development course on inclusive education strategies. A qualitative, interpretative research design was utilised whereby visual symbols alongside written reflections were analysed to identify changes in teachers’ knowledge, beliefs and practice. Findings revealed that teachers’ knowledge had increased, their attitudes towards learners with diverse needs was more positive, they felt more confident in their own abilities and more equipped for the task. Critical reflection emerged as an essential skill for teachers to be able to question their beliefs and rethink their practice but that this skill needed to be actively taught and encouraged in order to change prevailing perceptions of diversity and improve teaching practice
Cash transfers and caregivers : working together to reduce vulnerability and HIV risk among adolescent girls in Johannesburg, South Africa
Get PDFAbstract: In South Africa adolescent girls have the highest HIV incidence of any sex or age cohort. Scalable HIV-prevention interventions targeting this group are critical for epidemic control. Reaching 12.2 million children, the Child Support Grant mitigates the socio-structural drivers of HIV risk. This qualitative study of eight adolescents and their caregivers in Westbury, Johannesburg, explored how caregiving increases protective potential. ‘Caregiving’ enhanced the HIV risk-reduction benefits of ‘cash’ when characterised by substantial positive caregiver-adolescent involvement and adequate levels of control and consistency. Results underpin the value of social protection as an HIV-prevention modality and endorse investment in caregiver support programmes
A fuzzy-based optimization technique for the energy and spectrum efficiencies trade-off in cognitive radio-enabled 5G network
Get PDFAbstract: Please refer to full text to view abstract
Organizational change and its effects on throughput : a case study of Lonmin Mine Shafts
Get PDFAbstract: Several factors contribute to the effectiveness of an organization after an organization restructuring. Some of these factors are easily measurable while some are not. This study investigated the effect of employee attitude and perception towards organizational change (Theory of Constraints (TOC)) implementation using two Lonmin mine shafts as case studies. Sustainability of TOC was also considered. A quantitative research method was used for collecting data from two shafts in Lonmin Mine as a case study. The data was analysed using the IBM SPSS statistics 26 software. Descriptive and inferential statistical methods were performed on the data to test for statistical significance of the results. Findings from the study revealed that employees show remarkably positive attitude and perception towards organizational change. However, there is no correlation between the attitude and perception of employees and the organizational throughput
The awareness, perception and use of traditional and complementary medicine amongst adults in Shiela village in the North West Province, South Africa
Get PDFM.Tech. (Homoeopathy)Abstract: Complementary medicine (CM) treats and prevents illnesses and complements mainstream medicine; it does so by satisfying a medical demand which is not met by conventional medicine or diversifying the conceptual framework of medicine. The use of CM for the treatment and prevention of diseases has shown to grow over the years. The World Health Organisation (WHO) defines traditional medicine (TM) as an approach, health practice, belief and knowledge of an animal, plant and mineral based medicine, manual techniques and spiritual practices that are applied singularly or in combination to treat, prevent or diagnose diseases and maintaining health. The prevalence of CM use worldwide is estimated to be around 75% among adults, and the WHO has reported that 80% of the population in the world depend on TM for treatment. There were currently no studies conducted on the awareness, perception and use of TM and CM amongst adults in the North West province, South Africa. The aim of this study was to determine the awareness, perception, and use of TM and CM amongst adults in a rural village of the North West province by means of a questionnaire. This study was conducted in Shiela village in the North West province. A sample consisting of 150 adult males and females were recruited by means of flyers and posters with relevant permission obtained. The research took place in a community hall in Shiela village. Those included were given an information letter which invited them to take part in the study. The letter explained the purpose, procedure, and outcome of the study. Potential participants were screened for exclusion and inclusion criteria. The researcher was available to answer any questions or address any concerns about the study. On the day of the study conduction, potential participants were given consent forms to sign before filling in the questionnaires. Participants were given a private area where they could fill in the questionnaire. After completion, the questionnaires were was folded, sealed in an envelope, and placed into a box. Each questionnaire took approximately 15-20 minutes to complete. These boxes were stored in the strong room of the Homeopathy Health Centre, at the University of Johannesburg, Doornfontein campus, and only the researcher and the supervisor had access to these boxes. The participants remained anonymous as no identifying data, names or identity numbers was requested on the questionnaire. The data accumulated from the research was then analysed, interpreted, and captured with the assistance of a statistician from STATKON at the University of Johannesburg using cross tabulations, frequencies, and Chi-Square analysis..
Modeling system risk in the South African insurance sector : a dynamic mixture copula approach
Get PDFAbstract: In this paper, a dynamic mixture copula model is used to estimate the marginal expected shortfall in the South African insurance sector. We also employ the generalized autoregressive score model (GAS) to capture the dynamic asymmetric dependence between the insurers’ returns and the stock market returns. Furthermore, the paper implements a ranking framework that expresses to what extent individual insurers are systemically important in the South African economy. We use the daily stock return of five South African insurers listed on the Johannesburg Stock Exchange from November 2007 to June 2020. We find that Sanlam and Discovery contribute the most to systemic risk, and Santam turns out to be the least systemically risky insurance company in the South African insurance sector. Our findings defy common belief whereby only banks are systemically risky financial institutions in South Africa and should undergo stricter regulatory measures. However, our results indicate that stricter regulations such as higher capital and loss absorbency requirements should be required for systemically risky insurers in South Africa
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