41 research outputs found

    Examining the development of topic specific pedagogical content knowledge in stoichiometry in pre-service teachers

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    A thesis submitted to the Faculty of Science, University of the Witwatersrand In partial fulfillment of the requirements for the degree of Master of Science (Science Education) Johannesburg, 2017Over the past three years, National Senior Certificate diagnostic reports reported that learner performance in key chemistry topics remains an aspect for concern. In these reports, poor understanding of stoichiometry is identified as an underlying factor. On the other hand, the status of mathematics and science teaching has been under critique by several education researchers, pointing to poor teacher training in the subjects. One possible way to respond to the challenge in science education is to introduce and emphasize the development of Topic Specific Pedagogical Content Knowledge (TSPCK) as the professional knowledge for teaching science topics in Initial Teacher Education (ITE) programme. TSPCK is renowned for enabling teachers to pedagogically transform difficult content of specific science topics into forms best understandable by learners. This study examined the impact on the quality of TSPCK following an intervention that explicitly targeted the development of the competence to transform content knowledge using stoichiometry as a topic of learning. This examination happened as teacher plan to teach the topic. The study followed a Mixed Method research design and a case study as a research strategy. It was located in the methodology class of physical science IV. The participants were 10 pre-service teachers who were in their final year of Bachelor study in education (B. Ed). They were bound by the requirements of the course and their common choice of physical science as their major subject. These pre-service teachers were exposed to a TSPCK based intervention that explicitly targeted the development of TSPCK component interaction. More evidence of component interactions was comprehended as developing quality of TSPCK. Quantitative data was collected as a set of pre- and post-intervention TSPCK tests using existing, specially designed tools that were developed and validated in a separate study. Five (5) of the then pre-service were followed a year later after the intervention to measure the quality of TSPCK in the topic of intervention in order to determine the extent of retention of the quality of TSPCK since the intervention. Qualitative data was collected through face to face interviews to confirm observed patterns of retention. The findings in this study indicated that pre-service teachers experienced a visible improvement in the quality of their TSPCK in stoichiometry as a direct result of the intervention. Pre-service teachers showed more evidence of component interactions post the intervention. The results further indicated that pre-service teachers experienced the components of TSPCK to have different levels of difficulty when using them to transform the content in stoichiometry during planning. The component of ―conceptual teaching strategies‖ was found to be the most difficult. A year later, the quality of TSPCK in planning to teach the topic of the intervention was found to have been retained by the then pre-service teachers. Recommendations about the implementation of TSPCK in core topics in ITE are made. Firstly, for initial teacher education, it is recommended that courses such as methodology for teaching chemistry be structured as TSPCK based intervention. Secondly, more work need to be done in the examination of retention span of TSPCK. Thus, similar studies must be conducted in an effort to increase empirical evidence about the extent at which TSPCK is retained by beginning teachers.MT 201

    Synthesis, structural and magnetic properties of Nixco1-xFe2O4 and Co(RE)0:1Fe1:9o4 nano-ferrites.

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    Master of Science in Physics. University of KwaZulu-Natal, Durban 2017.Abstract available in PDF file

    Introduction: From the idea of Africa to the African idea of Africa

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    This special issue is part of the collaborative research project initiated by the Chair in Epistemologies of the Global South with Emphasis on Africa, based at the University of Bayreuth in Germany, and the Johannesburg Institute for Advanced Study (JIAS), based at the University of Johannesburg in South Africa. The collaborative project is entitled “The Changing African Idea of Africa and the Future of African Studies.” At the University of Bayreuth, the research project is also part of The African Multiple Cluster of Excellencesupported by the Deutsche Forschungsgemeinschaft (grant number EX 20521-390713894). The overarching agenda of The African Multiple Cluster of Excellence is that of reconfiguring African Studies, and at the centre of this is the imperative of doing AfricanStudies with Africans while also privileging African voices and intellectual/academic productions

    Strategic leadership as an approach to promote service delivery by local government in South Africa: a case study of the uThungulu District Municipality.

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    Doctor of Philosophy in Graduate School of Business and Leadership. University of KwaZulu-Natal, Durban 2016.This study is about how strategic leadership is enacted in not-for-profit organisations, with particular reference to municipalities. The Integrated Development Plan (IDP) was used to test the enactment of strategic leadership in the municipalities. It argues that because these are complex in nature, without strategic leadership, the IDP cannot be effective, hence, service delivery is highly unlikely to improve. Strategic leadership is envisaged as a possible solution to poor leadership and poor service delivery. Different research tools were used to collect data that were to be analysed to get results. The study found that the implementation of strategic leadership in the uThungulu District Municipality is not consistent with the theories of strategic leadership. Constraints in the implementation of strategic leadership were identified as poor leadership, political interference and corruption. A list of leadership competences was compiled and matched against service delivery. Poor service delivery, backlogs, poor communication, inability to align National, Provincial, and municipality projects, poor governance and inability to formulate policies were found to be the results of lack of strategic leadership. In this study, the concept of strategic leadership was extended by not only looking at areas like the rationale, formulation, role, principles, competencies, patterns, and challenges of strategic leadership, but also at the implementation and the challenges faced during the implementation process, which is the area that has not yet been researched extensively. The area, which is well-researched, is that of the private sector, and strategic leadership in this area was found to be consistent with the strategic leadership theories. The study proposes that The Quality of Life Survey should be conducted timeously to measure satisfaction of the community with regard to service delivery and to check if service delivery is reaching those people that it is intended to reach or not. Lastly the research proposes that Theory U by Otto Scharmer, (2007) must be used to address issues of corruption and political interference. This model deals with ways in which Municipal Managers can make sound decisions. It proposes that in order to address the challenges of a dynamic and complex environment, we need to move from destructive criticism to concentrate on the positive possibilities of the present

    Kimberlite weathering : effects of organic reagents

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    Kimberlite material is one of the primary sources of diamonds. Accelerated weathering that leads to a physical breakdown of the material over a short period of time has possible benefits in diamond processing such as reduction in the energy consumption when used as a pre-comminution stage. This study investigated accelerated weathering by utilising organic reagents; acetic acid, ethanol, formamide, n-hexane, oxalic acid, and urea, in comparison to the use of Cu2+ solution that was previously shown to be very effective in weathering kimberlite. Oxalic acid was the organic agent that showed promising weathering capabilities. However, the use of organic solutions was not as efficient as with Cu2+ solutions. Results showed that 67% of the particles passed 12 mm screen size in Cu2+ weathering compared to 48% in oxalic acid. It was also found that time of exposure had a small effect on weathering. Increasing the organic chemical concentration twofold, from 0.025 M to 0.5 M, improved weathering by 20% points. Different weathering mechanisms were observed at different solution concentration between oxalic acid (1st to 2nd order) and Cu2+ (2nd to 3rd order).De Beers Grouphttp://www.elsevier.com/locate/minenghb201

    Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

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    Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

    Independent and combined effects of improved water, sanitation, and hygiene, and improved complementary feeding, on child stunting and anaemia in rural Zimbabwe: a cluster-randomised trial.

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    BACKGROUND: Child stunting reduces survival and impairs neurodevelopment. We tested the independent and combined effects of improved water, sanitation, and hygiene (WASH), and improved infant and young child feeding (IYCF) on stunting and anaemia in in Zimbabwe. METHODS: We did a cluster-randomised, community-based, 2 × 2 factorial trial in two rural districts in Zimbabwe. Clusters were defined as the catchment area of between one and four village health workers employed by the Zimbabwe Ministry of Health and Child Care. Women were eligible for inclusion if they permanently lived in clusters and were confirmed pregnant. Clusters were randomly assigned (1:1:1:1) to standard of care (52 clusters), IYCF (20 g of a small-quantity lipid-based nutrient supplement per day from age 6 to 18 months plus complementary feeding counselling; 53 clusters), WASH (construction of a ventilated improved pit latrine, provision of two handwashing stations, liquid soap, chlorine, and play space plus hygiene counselling; 53 clusters), or IYCF plus WASH (53 clusters). A constrained randomisation technique was used to achieve balance across the groups for 14 variables related to geography, demography, water access, and community-level sanitation coverage. Masking of participants and fieldworkers was not possible. The primary outcomes were infant length-for-age Z score and haemoglobin concentrations at 18 months of age among children born to mothers who were HIV negative during pregnancy. These outcomes were analysed in the intention-to-treat population. We estimated the effects of the interventions by comparing the two IYCF groups with the two non-IYCF groups and the two WASH groups with the two non-WASH groups, except for outcomes that had an important statistical interaction between the interventions. This trial is registered with ClinicalTrials.gov, number NCT01824940. FINDINGS: Between Nov 22, 2012, and March 27, 2015, 5280 pregnant women were enrolled from 211 clusters. 3686 children born to HIV-negative mothers were assessed at age 18 months (884 in the standard of care group from 52 clusters, 893 in the IYCF group from 53 clusters, 918 in the WASH group from 53 clusters, and 991 in the IYCF plus WASH group from 51 clusters). In the IYCF intervention groups, the mean length-for-age Z score was 0·16 (95% CI 0·08-0·23) higher and the mean haemoglobin concentration was 2·03 g/L (1·28-2·79) higher than those in the non-IYCF intervention groups. The IYCF intervention reduced the number of stunted children from 620 (35%) of 1792 to 514 (27%) of 1879, and the number of children with anaemia from 245 (13·9%) of 1759 to 193 (10·5%) of 1845. The WASH intervention had no effect on either primary outcome. Neither intervention reduced the prevalence of diarrhoea at 12 or 18 months. No trial-related serious adverse events, and only three trial-related adverse events, were reported. INTERPRETATION: Household-level elementary WASH interventions implemented in rural areas in low-income countries are unlikely to reduce stunting or anaemia and might not reduce diarrhoea. Implementation of these WASH interventions in combination with IYCF interventions is unlikely to reduce stunting or anaemia more than implementation of IYCF alone. FUNDING: Bill & Melinda Gates Foundation, UK Department for International Development, Wellcome Trust, Swiss Development Cooperation, UNICEF, and US National Institutes of Health.The SHINE trial is funded by the Bill & Melinda Gates Foundation (OPP1021542 and OPP113707); UK Department for International Development; Wellcome Trust, UK (093768/Z/10/Z, 108065/Z/15/Z and 203905/Z/16/Z); Swiss Agency for Development and Cooperation; US National Institutes of Health (2R01HD060338-06); and UNICEF (PCA-2017-0002)

    Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK

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    Background A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials. Methods This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674. Findings Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0–75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4–97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8–80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3–4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation. Interpretation ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials

    Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK.

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    BACKGROUND: A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials. METHODS: This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674. FINDINGS: Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0-75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4-97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8-80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3-4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation. INTERPRETATION: ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials. FUNDING: UK Research and Innovation, National Institutes for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, Bill & Melinda Gates Foundation, Lemann Foundation, Rede D'Or, Brava and Telles Foundation, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and AstraZeneca

    Examining the Views of Unemployed Commercial Subject Educators on Their Preparedness to Become Entrepreneurs.

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    This study sought to establish the views of unemployed commercial subject educators on their preparedness to become entrepreneurs.&nbsp; The study was motivated by the fact that some of these educators have been exposed to entrepreneurship since they were in grade 7 through a subject such as Economic and Management Sciences. It is assumed that after graduation they have a good understanding of entrepreneurship, and they would be able to start their businesses instead of remaining at home unemployed. Only unemployed commercial subject educators were interviewed. Snowballing sampling was used to locate prospective participants since they were scattered all over South Africa. All the study participants were based in KwaZulu Natal Province. The study found that educators of commercial subjects have sufficient theoretical knowledge to become entrepreneurs, but they are afraid to venture into businesses because they feel that theoretical knowledge without practical experience will adversely impact their ability to become successful entrepreneurs. They are doubtful regarding their ability to use their theoretical knowledge to solve problems in real-life situations. The contribution of this study provides insight on the importance of students’ practical exposure to real life entrepreneurship for boosting their confidence to start businesses.&nbsp; The study ascertains that an entrepreneurial mindset, attitude, spirit and self-efficacy, without exposure to practical entrepreneurship, does not provide sufficient incentive for a person to start a business
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