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A case study of public transport preference in Cape Town using the best-worst scaling method
No full textCommuter preference and service satisfaction influences transport mode choice and even when there is no choice (captive travellers) there is dignity in providing minimal quality. It has been proven that a shift from private transport towards public transport is rare. It is therefore easier to improve satisfaction or perceptions of captive public transport users than to move car users to public transport. Except in Greece where well-timed transport improvement during an economic downturn resulted in an increase in public transport use. The national fiscus has competing priorities it supports infrastructure, health, education, public transport and many other government services. Justification for funding public transport in lieu of other government priorities is linked to commuter demand. Commuter demand is measured by the number of passengers per mode or trip. The goal for public transport modes is full occupancy of vehicles. Higher occupancy rates justify the trip and by implication the fiscal investment on the trip and or mode. Commuters choose transport modes based on a number of attributes such as: cost, travel time, access time, frequency of service, comfort, safety etc. Therefore, improving public transport users preference capture may lead to better informed public transport improvement investments decisions. Case 2 best worst scaling is a survey method that compares varying attributes to one another by soliciting a ranking of one best and one worst. The method allows for at least three attributes per domain of investigation. Each attribute's attribute level is compared, in a choice set, to other attributes' attribute level. Commuters seek a transport service from origin to destination that is safe, economical and comfortable. Commuter studies show that needs and levels of satisfaction vary from person to person and mode choices are usually restricted by affordability. However, as soon as there is affordability for better options, commuters always choose the most responsive mode. In urban areas this choice is evidenced by higher percentage of low-occupancy private car commute. The aim of this research was to determine the applicability of case 2 best worst scaling; and commuter preferred service attribute levels for travel, safety and comfort for Bus, Minibus Taxi, MyCiTi and Train commuters in Cape Town. The study used attributes and dissatisfaction data from the National Household Travel Survey to identify key attributes and attribute levels for investigation. Case 2 best worst scaling surveys were designed as follows: three domains – travel, safety and comfort; three to four attributes per domain; and each attribute tiered into attribute three levels. The field work was intercept surveys to Cape Town commuters. Data were analysed using R and yielded the following key findings: Case 2 best worst scaling is applicable for preference studies in South Africa and beyond; paying more, experiencing sudden braking and overcrowding were least preferred (disutility); there were nuanced variations for other attribute levels based on mode and demographic groups
Outcomes of mechanical thrombectomy at a single-centre tertiary level public health care hospital in South Africa
Get PDFIntroduction: Mechanical thrombectomy (MT) is standard of care for acute ischemic stroke from large vessel occlusion following randomized controlled trials performed largely in high-income countries. Limited data exists on its effectiveness in the real-world setting, particularly in low- and middle-income countries. We aimed to evaluate the safety and efficacy of MT in a public hospital in Cape Town, South Africa. Methods: We evaluated acute ischaemic stroke patients presenting consecutively to Groote Schuur Hospital between 01 January 2018 to 01 January 2022 with proximal intracranial occlusion in the anterior circulation treated with MT within 6 hours from onset using CT and CTA imaging-based protocols. Demographic, clinical, radiological and procedural data were obtained from the stroke unit database. Recanalization was evaluated post-procedure by modified Treatment in Cerebral Infarction score (mTICI). We assessed functional independence (modified Rankin scores (mRS) 0-2) and mortality at 90 days. Results: Thrombectomies were performed in 84 patients during the study period. The median age was 56 years and 51% of participants were female. Median National Institute of Health Stroke Score was 18 and median baseline Alberta Stroke Programme Early CT score was 8. Bridging thrombolysis was given to 65% of participants. Median time from symptom onset to reperfusion was 339 minutes. Successful recanalization (mTICI 2b/3) was obtained in 62%. At 90 days, 34 % of participants reached functional independence and mortality was 34% . Conclusions: We achieved similar rates of recanalization and functional independence to that seen in trials in high-income countries using basic imaging despite a higher mortality and longer median time to reperfusion. These data support the effectiveness of MT in a public hospital in south Africa despite the challenges of providing emergent stroke care in a resource-constrained setting
Antarctic sea ice phytoplankton growth rates and survival mechanisms
Get PDFPhytoplankton play an important role in the Southern Ocean food web being the primary producers of food, particularly in winter, and partaking in the uptake of CO2 from the atmosphere via photosynthesis. Despite being photosynthetic organisms, phytoplankton survive at the bottom of sea ice where there is very little irradiance for up to 6 months. Sea ice phytoplankton are understudied. This is mainly because in situ studies on sea ice are not only expensive but logistically difficult. Some researchers have elected to bring sea ice phytoplankton from the Southern Ocean to land-based facilities. This has seen some logistical difficulties as it meant either changing the habitat phytoplankton would have been for transportation, thus changing the species originally found in the Southern Ocean or transporting phytoplankton in ice cores and losing species due to brine drainage or osmotic stress from temperature changes in the core. The objectives of this study were to optimize a previously designed hybrid tank for the purpose of obtaining and preserving phytoplankton species from the Marginal Ice Zone of the Southern Ocean to land-based facilities. The study also included design of an environmental chamber to be used for housing phytoplankton obtained during experimentation. Responses to temperature and irradiance variation on phytoplankton from the Marginal Ice Zone of the Southern Ocean were then evaluated using the designed environmental chamber. The solid-liquid hybrid system known as the hybrid tank was successfully optimized by reducing the size of the tank, adding irradiation to the tank, and making improvements to the sampling protocol. The tank was used to obtain ice cores from the Southern Ocean to the University of Cape Town in winter 2022. Post the winter cruise one hybrid tank sample was melted, and microscopic analysis conducted on the sample. In comparison with transportation of phytoplankton in a solid core and in a liquid melt in the dark, the hybrid tank resulted in an increase in phytoplankton cell concentration. Furthermore, the optimized hybrid tank improved preservation of species transported when compared to the initial tank. A desktop environmental chamber made from Perspex and insulated with polystyrene was successfully designed. The environmental chamber offers temperature and irradiation control by making use of a cold plate attached to a chiller and an LED light. Experiments conducted on the diatom species revealed that all the sea ice species were shade adaptive being photo inhibited at irradiances beyond 42μmolm-2s-1 with the exception of Navicula spp, Cylindrotheca closterium and the unidentified pennates. The diatom species also preferred warmer environments i.e., 8°C to 5°C
A systematic review on the neurological and psychopathological correlates of pica
Get PDFPica, the consumption of non-nutritive substances for longer than 30 days, has had several aetiologies reported. These include micronutrient deficiency, psychological and developmental disorders, and neurological and neurochemical pathologies, with a predominant focus in literature on micronutrient deficiency. Thus, a thorough exploration of the possible neurological (i.e., diagnosed conditions, neuroanatomical regions, neuropsychological profiles, neurodevelopmental disorders, neurotransmitter systems) and psychopathological (i.e., diagnosed conditions, psychological mechanism) correlates is needed. Although a recent review on the topic exists, it has not been reported on systematically. The aim of this systematic review (SR) is to firstly, provide a comprehensive overview of the existing research pertaining to neurological and psychopathological correlates of pica. Secondly, to provide a deeper understanding of pica onset and progression and to inform comorbid diagnosis and treatment of pica. Methodology of the review followed the PRISMA 2020 guidelines. Databases searched included PubMed, Scopus, Science Direct, EbscoHost (Academic Search Premier, CINAHL, Health Source: Nursing/Academic Edition, APA PsycArticles, APA PsycInfo, Medline). Methodological evaluation of studies was conducted using the Joanna Briggs Institute (JBI) Critical Appraisal Tool. An adapted JBI checklist was used for each of the study designs including case reports, case series, case control, and cross-sectional designs. 5468 journal articles were identified, 1102 articles were checked using eligibility criteria, and 15 articles were included in the review. Findings showed that the most prevalent neurological conditions correlated to pica included neurodegenerative diseases (Fronto-temporal dementia; Alzheimer's disease and Multi-infarct Dementia), acquired brain injury and stroke. The neuroanatomical regions most associated with pica included the frontal and temporal cortex as well as limbic system structures. Neuropsychological profiles of individuals with pica were in keeping with the neuroanatomical regions described and included semantic memory deficit, aphasia (Transcortical Sensory and Wernicke's) as well as cognitive difficulties following left temporal (verbal learning, memory, and reasoning) and right frontal (cognitive switching) damage. The most prevalent neurodevelopmental disorders associated with pica were Intellectual Disability and Autism-Spectrum Disorder. Successful treatment of pica mainly included serotonin inhibitors or antagonists, indicating a possible correlation between the dysregulation of serotonin neurotransmitters and pica. In addition, the most prevalent psychopathological correlates of pica included OCD, schizophrenia, and depression, with the relief of anxiety being the most prominently reported reason for engaging in pica behaviour. Furthermore, even though these findings prove to be promising, the studies included were predominantly case report or case series, therefore a recommendation for larger scaled studies is warranted
The development of consensus-based pre-hospital core competencies and outcomes as a component of specialist emergency physician training - a South African-based study
No full textBACKGROUND: South African Emergency Medicine registrars undertake between one and three-month pre-hospital work placements as a component of the specialist training programme. Anecdotally, the experiences of trainees nationally vary substantially which may be attributed to the lack of a curriculum to guide expected graduate outcomes, teaching, learning or assessment in Pre-Hospital Emergency Medicine (PHEM). Although efforts are underway to renew the EM curriculum in SA by the College of Emergency Medicine (CEM), this is the first body of research dedicated towards a pre-hospital curriculum for South African EM specialist training. AIM: To seek consensus on expected graduate level pre-hospital core competencies and generate broad learning outcomes for the SA EM specialist training curriculum. METHODS: A modified nominal group technique (NGT) was used to derive PHEM competencies and outcomes for specialist trainees. A scoping review of the literature informed the NGT by extrapolating global pre-hospital competencies and outcomes for registrars. Fourteen experts in either pre-hospital education and/or practice and specialist EM physicians were purposively recruited. A summary of core competencies and outcomes were presented to the panel over two virtual sessions. PHEM core competencies and broad-level outcomes were generated through consensus and context-specific gaps in the international literature were addressed and suggestions also presented for consensus. RESULTS The panel concluded that the WHO Emergency Care Systems Framework (ECSF) was appropriate to organise competencies and outcomes. The consensus process yielded 6 core competencies and 36 broad-level outcomes; eleven outcomes for scene response, 21 for transport and 4 for facility. CONCLUSION: The consensus process allowed researchers to design a curriculum framework for a PHEM module which can inform the specialist training curriculum for the CEM SA. Aviation for Health Care Provider and Hospital Major Incident Medical Management and Support courses potentially address specific outcomes. Self-directed and experiential learning have been highlighted as crucial teaching-learning methodologies, and opportunities identified for transprofessional collaboration. The results reported here could be used in the next steps of curriculum development
Ways of seeing women's history: an action research study of student responses to a document-based lesson sequence centring black women in a historical narrative
Get PDFThis thesis investigates a document-based enquiry as a way of integrating the teaching of women's history in the classroom. This need arises given women's misrepresentation, marginalisation, and erasure by history teaching practice and curricula in high schools in South Africa and further afield. Existing research shows students resist valuing women's history when presented as token additions to the traditionally male-centred narrative. Gaps identified in the disciplinary and critical approaches to teaching history provide a theoretical framework for foregrounding the necessity of examining the impact of affect in enabling as well as in obstructing student learning. Scholarship on resistance to learning both within and beyond history education further facilitates theorising the importance of affect in impeding learning. In this action research study conducted in my own Grade 11 history classroom, I curated accessible documents centring Black women in events that secured the ending of bus segregation in Montgomery, Alabama in the 1940s-1950s. Textbook extracts presented alongside documentary evidence allowed my eight students in their penultimate year at an all-girls school to interrogate the divergent narratives. To elicit students' enthusiastic participation and close reading of the material, I sequenced engaging pedagogical activities across ten lessons. Plenary and group discussions, constructions, and writing, along with individual reflections, were collected as data. My positionality is evident in my choice of Tetreault's feminist framework to analyse how the enquiry informed students' ways of seeing events in Montgomery, and reflexive thematic analysis is used to analyse how the enquiry informed students' ways of seeing the construction of textbook history. My findings indicate that the extended enquiry enabled all students to critique the textbooks' erasure and misrepresentation of women. Several students' affective engagement enhanced their capacity to enact sophisticated criticality and disciplinary learning that exceeded my expectations. By contrast, affect unconsciously partially impeded the learning of others, as their embedded notions absorbed from the social milieu they inhabit compelled them at times to resist using aspects of the documentary evidence consistently. In response, I contribute three reconceptualised disciplinary, critical, and psychosocial literacy lenses as interlocking pedagogical approaches to capacitate and enhance student learning in the history classroom. They would also assist teachers in noticing and responding constructively to students experiencing knowledge as discomfiting their sense of themselves and how they wish to be seen socially. My study highlights the dearth of research in history education that uses an affective and psychosocial lens to examine student learning in the classroom, and shows that this lens is essential to facilitating and enhancing student progression in this subject
The petrogenesis of the Pliocene Araral stratovolcano in the Andean Central Volcanic Zone, Northern Chile
Get PDFThe Altiplano-Puna Volcanic Complex (APVC) is a silicic volcanic complex in the Central Andean Volcanic Zone (CVZ). The APVC is underlain by the thickest known crust in a continental arc setting and the largest known magma body – the Altiplano-Puna Magma Body (APMB). Lavas of the APVC and CVZ are compositionally heterogeneous with elevated Sr isotope ratios relative to mantle-derived lavas and the rest of the Andean Volcanic Arc. The lavas are produced by subduction-induced magmatism and magma differentiation processes, such as crustal assimilation as the magma ascends through the thick crust. The APMB is a large regional melt anomaly proposed to be the source of APVC ignimbrites and the lavas of the APVC have a decreased degree of interaction with the APMB towards its margins. Mafic volcanism in the APVC is rare and is concentrated along the western margin of the APMB. These mafic lavas are predominantly Quaternary in age with some Pliocene lavas. Mafic volcanism in the APVC, and more specifically mafic volcanism during the Pliocene, is understudied
Exchange traded funds and their association with the volatility of the daily returns of major South African banks
Get PDFThis dissertation examines whether the degree of ownership of major South African Bank shares by the Exchange Traded Fund (ETF) market in South Africa along with ETF's unique trading dynamics (for the purposes of this dissertation, “ETF's unique trading dynamics” refers to the relationship between ETFs and their constituent shares through the ETF share creation and redemption process and the purchase and sale of constituent shares), has an association with the volatility of the South African Major Bank's daily returns. This dissertation determines the degree of ownership by the ETF market and its trading dynamics using publicly available data through the identification and collation of publicly available data obtained from third-party data providers. Using a GARCH model process to estimate the volatility of daily returns, this dissertation then incorporates the degrees of ETF ownership and ETF trading dynamics variables as external regressors to assess whether there was a statistically significant association in explaining the volatility of daily returns of the Major South African Banks shares. The results of the dissertation are mixed. Concerning the degree of ETF ownership, there is evidence of a statistically significant negative association between the degree of ETF Ownership and the volatility of daily returns for two of the six shares, while in the instances of the remaining shares, there is no statistically significant association. With respect to ETF unique trading dynamics, driven by ETF-Specific Events (which, for the purposes of this dissertation, means the introduction of a new ETF into the market, the creation of new ETF shares, and redemption of existing ETF shares), no statistically significant association is found between the volatility of daily returns for any of the shares. This study reveals a nuanced relationship between ETF ownership and stock volatility in major South African banks, demonstrating that while higher ETF ownership may reduce volatility in some bank shares, its impact is not universal across the sector. These findings may be useful for investors, financial analysts and policymakers who are interested in understanding the potential impact ETFs may have on equity markets, and who may use this information for risk management, advising on investment strategies, and shaping regulations around ETFs. This research adds to the body of knowledge in relation to understanding of the role of ETFs in financial market stability and their potential impact on constituent share price volatility, with specific reference to emerging markets like South Africa, offering valuable insights for various market stakeholders
Implications of IFRS 16: leases - evidence from JSE-listed telecommunication companies
Get PDFThis study investigates the implications of the new leasing standard, IFRS 16 Leases, on companies in the Telecommunications sector of the Johannesburg Stock Exchange. The International Accounting Standards Board's upcoming Post-Implementation Review of IFRS 16 is considered in this study (International Accounting Standards Board, 2023). IFRS 16, which is effective from 1 January 2019 (IFRS Foundation, 2016a), introduces requirements for lessees to present and disclose assets and liabilities that arise from leasing arrangements as part of their statement of financial position at initial recognition (IFRS Foundation, 2016a). The analysis of the impact is performed through a financial statement analysis, as well as financial ratio analysis, which is a different from the constructive capitalisation model developed by Imhoff et al. (1991, 1997). The findings of this study suggest that the implementation of IFRS 16 Leases led to a rise in reported assets and liabilities in the financial statements, which had an impact on key financial ratios for companies that rely on leased assets as part of their operations. The study's findings also show that as more leasing information is available, the implementation of IFRS 16 has led to financial statements that provide more transparent and comparable financial information
Enablers of and barriers to digital innovation success: a comparative study of structured versus unstructured technology innovation environments in Kenya
Get PDFWestern theories dominate research on digital innovation in the Global South, neglecting contextual differences. Further, current research lacks focus on how structured versus unstructured innovation environments affect digital innovation success in these contexts. This study's investigation and findings centre on the phenomenon of ‘digital innovation success', focusing on digital startups and innovators in Kenya. The study has two objectives: to isolate the enablers of and barriers to digital innovation success in Kenya and to compare the success factors between structured versus unstructured innovation environment. This study uses multiple cases with semi-structured interviews, document reviews, and media analysis. Kleine's Choice Framework was used as the core theoretical lens, from which a conceptual model that guided data analysis was developed. The framework enabled visualisation of digital innovation success systemically and holistically as a development outcome that digital innovators in the Global South strive to achieve. The framework was also used to identify and evaluate the conditions (agency and structure resources) under which digital innovation success opportunities emerge within structured and unstructured environments, thereby revealing their differences and similarities. The study findings in respect of the first objective revealed Entrepreneurship Support Organisations and Innovation Intermediaries as the most influential contextual factor on digital innovation success in Kenya. Results for the second objective revealed structured environment as a significant enabler of success in Kenya but warns against assuming all structures are neutral. The study's first theoretical contribution is an explanation of contextual enablers of and barriers to digital innovation success in the Global South. Second, a theoretical demonstration of how Kleine's Choice Framework can be used as a lens for Information Systems research and for building a conceptual model. The study's first practical contribution is that digital innovators can make informed decisions on the innovation environment that best fits their strengths and startup needs. Second, government and policy makers can better tailor their support for each environment. Further, the study highlights the difference between startups and MSMEs, urging tailored policies for digital startups. Third, investors can leverage the study findings to invest strategically in digital innovation ventures in the Global South