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The advocacy for writing in science and STEM‐related fields through reasoning‐based writing, critical thinking and argumentation has been accentuated as a core competence in curriculum documents. In South Africa, the CAPS document for Physical Sciences acknowledged the importance of writing and consequently, call on teachers to engage in teaching language across the curriculum. This study examined the characteristics of writing prompts in three selected samples of textbooks to understand how writing is addressed in the Physical Sciences textbooks. Specifically, the study examined the frequency and characteristics of writing prompts included in the chemistry component of three selected Physical Sciences textbooks for Grade 12 learners. A total of 533 writing prompts were identified and analyzed using a coding scheme adopted for the study. Findings revealed that learners are prompted to write in variety of ways, with prompts that positioned them to explain why, discuss your ideas, explain how and explain what. While the prompts that ask learners to explain why and discuss your ideas were the most frequently coded, the press to write their reasoning with specific features that are inherent in the respective topics were inadequate. The implications for curriculum developers are the need for explicit instructions on the length of writings required, and for authors to develop adaptable guidelines to enable textbook users understand the writing expectations. [ABSTRACT FROM AUTHOR]

South Africa lags behind in terms of competing globally in science and technology. Thus, the purpose of the study was to investigate teacher factors that influenced learners' motivation to learn science in a secondary school. The study also aimed to determine whether significant differences in motivation regarding teacher influence existed among age groups and genders. The research was conducted in a public secondary school in Gauteng province, South Africa with 462 learners from Grade 8 to Grade 11. Using a quantitative approach, the learners completed a questionnaire that involved several motivation constructs (mastery and performance goal oriented). The study identified some problems that could impact on learner motivation and also found that some significant differences existed among different grades and genders. A number of recommendations were made regarding the teacher's role in motivating science learning. [ABSTRACT FROM AUTHOR]

The research reported here examined the outcome of using interactive simulation technology (IST) as a guided-inquiry approach to enhance learners' conceptual knowledge of electrostatics in physics. Participants were Grade 11 physical sciences learners (n = 60) and a teacher from a rural school in South Africa. Learners were randomly assigned to an experimental group (n = 30) that took part in the intervention lesson using the integration of IST in the science classroom, and a control group (n = 30) that continued with the conventional teaching method. We adopted a mixed-method approach for this research. Data were collected through a pre-post achievement instrument, classroom observations, and focus group interviews. Data were analysed using the Mann-Whitney U-test, the Wilcoxon signed-rank test, and content analysis. It was found that the mean rank rating of the pre-test results for learners in both groups was not significantly different. However, the Mann-Whitney U-test indicated that learners' conceptual understanding measured in the post-test result was greater for the experimental group (mean rank gain score = 38.83) compared to the control group (mean rank gain score = 22.17), U = 200.0, p = 0.000185. This finding indicates that integrating IST into inquiry-based activities can be used efficiently to improve learners' in-depth knowledge of science concepts. [ABSTRACT FROM AUTHOR]

As South African cities urbanise alongside climate change, resource constraints, and socio-economic challenges, water sensitive (urban) design (WSD) is slowly gaining traction as a framework to address water security goals and entrench resilience. This article reflects on the progression of WSD in South Africa and discusses the broadening of its initial association with stormwater and physical infrastructure to include critical governance and institutional arrangements and social engagements at the core of a water sensitive transition. The approach is being adapted for the socio-economic challenges particular to South Africa, including basic urban water and sanitation service provision, WSD related skills shortages, a lack of spatial planning support for WSD, and the need for enabling policy. Since 2014, a national WSD Community of Practice (CoP) has been a key driver in entrenching and advancing this approach and ensuring that the necessary stakeholders are involved and sufficiently skilled. The WSD CoP is aimed at promoting an integrative approach to planning water sensitive cities, bridging the gaps between theory and practice and blending the social and physical sciences and silo divisions within local municipalities. Three South African examples are presented to illustrate the role of a CoP approach with social learning aspects that support WSD : (1) the "Pathways to water resilient South African cities" interdisciplinary project which shows the institutional (policy) foundation for the integration of WSD into city water planning and management processes; (2) the Sustainable Drainage Systems training programme in the province of Gauteng which demonstrates a skills audit and training initiative as part of an intergovernmental skills development programme with academic partners; and (3) a working group that is being established between the Institute for Landscape Architecture in South Africa and the South African Institution of Civil Engineering which illustrates the challenges and efforts of key professions working together to build WSD capacity. [ABSTRACT FROM AUTHOR]

The low enrolment, lack of interest, exacerbated by the general poor performance in physical science in South Africa paints a gloomy picture about the status of physical science in the country. Despite the fact that there might be other factors at play, one factor which cannot be ignored is the discourse about the use of language in the science classroom as viewed by physical science teachers. In the study reported on here a quantitative methodology was followed in which a closed-ended questionnaire survey was used as data collection tool. In the study we examined South African physical science teachers' perceptions about the language use in science classrooms, and the study was informed by the Vygotskian socio-cultural theory (SCT). The target population from which a sample size of 37 physical science teachers was systematically sampled was high school classroom teachers and learners in Grades 10, 11 and 12 in the Ngaka Modiri Molema district of the North West province of South Africa. The study revealed that physical science teachers encountered difficulties with meanings of non-technical words used in science context. The conclusion drawn was that many physical science teachers were not proficient in the discourse of the science classroom and this often compromised their effectiveness in the teaching and learning of science. The main difficulty was confusion in differentiating between technical and non-technical words and the lack of convincing explanations of meanings of these words in teaching and learning. Key among the recommendations of this study was the need to address teachers' challenges with regard to the language use and the implications thereof. [ABSTRACT FROM AUTHOR]

Background: Seasonality of food availability, physical activity, and infections commonly occurs within rural communities in low and middle-income countries with distinct rainy seasons. To better understand the implications of these regularly occurring environmental stressors for maternal and child health, this study examined seasonal variation in nutrition and health care access of pregnant women and infants in rural South Africa. Methods: We analyzed data from the Venda Health Examination of Mothers, Babies and their Environment (VHEMBE) birth cohort study of 752 mother-infant pairs recruited at delivery from August 2012 to December 2013 in the Vhembe District of Limpopo Province, the northernmost region of South Africa. We used truncated Fourier series regression to assess seasonality of antenatal care (ANC) attendance, dietary intake, and birth size. We additionally regressed ANC attendance on daily rainfall values. Models included adjustment for sociodemographic characteristics. Results: Maternal ANC attendance, dietary composition, and infant birth size exhibited significant seasonal variation in both unadjusted and adjusted analyses. Adequate frequency of ANC attendance during pregnancy (≥ 4 visits) was highest among women delivering during the gardening season and lowest during the lean (rainy) season. High rainfall during the third trimester was also negatively associated with adequate ANC attendance (adjusted OR = 0.59, 95% CI: 0.40, 0.86). Carbohydrate intake declined during the harvest season and increased during the vegetable gardening and lean seasons, while fat intake followed the opposite trend. Infant birth weight, length, and head circumference z-scores peaked following the gardening season and were lowest after the harvest season. Maternal protein intake and ANC ≤ 12 weeks did not significantly vary by season or rainfall. Conclusions: Seasonal patterns were apparent in ANC utilization, dietary intake, and fetal growth in rural South Africa. Interventions to promote maternal and child health in similar settings should consider seasonal factors. [ABSTRACT FROM AUTHOR]

Background: The World Health Organization recommends "same-day" initiation of antiretroviral therapy (ART) for HIV patients who are eligible and ready. Identifying efficient, safe, and feasible procedures for determining same-day eligibility and readiness is now a priority. The Simplified Algorithm for Treatment Eligibility (SLATE) study evaluated a clinical algorithm that allows healthcare workers to determine eligibility for same-day treatment and to initiate ART at the patient's first clinic visit.Methods and Findings: SLATE was an individually randomized trial at three outpatient clinics in urban settlements in Johannesburg, South Africa and three hospital clinics in western Kenya. Adult, nonpregnant, HIV-positive, ambulatory patients presenting for any HIV care, including HIV testing, but not yet on ART were enrolled and randomized to the SLATE algorithm arm or standard care. The SLATE algorithm used four screening tools-a symptom self-report, medical history questionnaire, physical examination, and readiness assessment-to ascertain eligibility for same-day initiation or refer for further care. Follow-up was by record review, and analysis was conducted by country. We report primary outcomes of 1) ART initiation ≤28 days and 2) initiation ≤28 days and retention in care ≤8 months of enrollment. From March 7, 2017 to April 17, 2018, we enrolled 600 patients (median [IQR] age 34 [29-40] and CD4 count 286 [128-490]; 63% female) in South Africa and 477 patients in Kenya (median [IQR] age 35 [29-43] and CD4 count 283 [117-541]; 58% female). In the intervention arm, 78% of patients initiated ≤28 days in South Africa, compared to 68% in the standard arm (risk difference [RD] [95% confidence interval (CI)] 10% [3%-17%]); in Kenya, 94% of intervention-arm patients initiated ≤28 days compared to 89% in the standard arm (6% [0.5%-11%]). By 8 months in South Africa, 161/298 (54%) intervention-arm patients had initiated and were retained, compared to 146/302 (48%) in the standard arm (6% [(2% to 14%]). By 8 months in Kenya, the corresponding retention outcomes were identical in both arms (137/240 [57%] of intervention-arm patients and 136/237 [57%] of standard-arm patients). Limitations of the trial included limited geographic representativeness, exclusion of patients too ill to participate, missing viral load data, greater study fidelity to the algorithm than might be achieved in standard care, and secular changes in standard care over the course of the study.Conclusions: In South Africa, the SLATE algorithm increased uptake of ART within 28 days by 10% and showed a numerical increase (6%) in retention at 8 months. In Kenya, the algorithm increased uptake of ART within 28 days by 6% but found no difference in retention at 8 months. Eight-month retention was poor in both arms and both countries. These results suggest that a simple structured algorithm for same-day treatment initiation procedures is feasible and can increase and accelerate ART uptake but that early retention on treatment remains problematic.Trial Registration: Clinicaltrials.gov NCT02891135, registered September 1, 2016. First participant enrolled March 6, 2017 in South Africa and July 13, 2017 in Kenya. [ABSTRACT FROM AUTHOR]

This paper examines whether tobacco expenditure leads to the crowding out or crowding in of different expenditure items in South Africa. We apply genetic matching to expenditure quartiles of the 2010/2011 South African Income and Expenditure Survey. Genetic matching is a more appealing approach for dealing with the endogeneity of tobacco expenditure that often plagues studies using systems of demand equations. Further, genetic matching provides transparent measures of covariate balance giving the analyst objective means of assessing match success. We find that the poorest tobacco consuming households in South Africa consistently allocate smaller budget shares towards food items than non-smoking households. Specifically, we find that dairy, fruits, nuts and oils are displaced in favour of tobacco expenditure in the two poorest quartiles. Unsurprisingly, food items are never displaced for households in the top two quartiles, given these households’ greater access to resources. Like other studies in the literature, we find that tobacco expenditure consistently crowds-in alcohol across all quartiles confirming the strong complementarities between the two. [ABSTRACT FROM AUTHOR]

The experiences of pre-service teachers who come from rural backgrounds differ widely from those who are from urban schools. It can be assumed that these experiences play a crucial role in shaping their teaching careers during and after the formal teacher training. Even though much research has already dwelt on the various challenges experienced by rural schools in South Africa, little has been done on pre-service teachers' perspectives. Using an exploratory research method, this article explores the status of physical sciences teaching and learning in rural schools in one of the most disadvantaged provinces of South Africa, using pre-service teachers enrolled in a rural-based university as the participants. While many factors were reported as hindering the effective teaching and learning of physical sciences in rural schools, it was found that some schools and teachers used some appropriate strategies to promote teaching and learning. [ABSTRACT FROM AUTHOR]

Uranium (U) measurements in water, soil, and food related to gold mining activities in populated areas in Gauteng Province, South Africa, suggest the possibility of exposure levels that may lead to adverse health consequences, including cancer. Theoretical considerations on pathways of human uptake of significant exposures are plausible, but few data on directly measured human exposure are available. A cross-sectional study was conducted using human measurements to compare U levels with other settings around the globe (based on literature review), to explore potential exposure variability within the province, and to test the feasibility of recruiting subjects partially coming from vulnerable and difficult-to-reach populations. Wards of potentially high (HE) and low exposure (LE) were identified. Composite hair samples representing the respective local populations were collected from regular customers of selected barber shops over a period of 1–2 months. A total of 70 U concentrations were determined in 27 composite samples from 1332 individuals. U concentrations ranged from 31 μg/kg to 2524 μg/kg, with an arithmetic mean of 192 μg/kg (standard deviation, 310 μg/kg) and a median of 122 μg/kg. Although HE wards collectively showed higher U levels than LE wards (184 vs 134 μg/kg), differences were smaller than expected. In conclusion, detected U levels were higher than those from most other surveys of the general public. The barber-based approach was an efficient hair collection approach. Composite hair samples are not recommended, due to technical challenges in measuring U, and individual hair samples are needed in follow-up studies to determine predictors of exposure. [ABSTRACT FROM AUTHOR]

Introduction: Research has demonstrated benefits of social capital on depression, but variations in this relationship by geographic characteristics such as urbanicity have rarely been investigated. Methods: Using survey data on 4,209 Ghanaian and 3,148 South African adults aged 50 and above from the World Health Organization (WHO) Study on Global AGEing and Adult Health (SAGE), exploratory and confirmatory factor analyses were conducted to extract dimensions of social capital from survey items. Structural equation models with the extracted factors were then used to estimate the associations between social capital and depression in each sample and assess differences between urban and rural settings with measurement and structural invariance tests. Results: Factor analyses suggested three dimensions of social capital representing community engagement, sociability, and trust. Urbanicity did not substantially modify the effects of social capital on depression in either setting, but urban-rural differences in the measurement and level of social capital were observed. Urban Ghanaian older adults were less socially integrated and trusting than older rural residents (standardized mean difference: -0.28, -0.24, and -0.38 for community engagement, sociability, and trust, respectively) while urban South African older adults appeared less engaged in community activities but significantly more trusting and socially active informally than older rural residents (standardized mean difference: -0.33, 0.30, and 0.17 for community engagement, sociability, and trust, respectively). Moreover, while trust was associated with a lower risk of depression in South Africa overall, sociability and trust were associated with an increased risk of depression in Ghana. Conclusions: Results indicate that the composition and average levels of social capital differ between urban and rural older adult residents in Ghana and South Africa although urban-rural differences in the strength of the association between social capital and depression were not substantial. Furthermore, the associations between social capital and depression are context-specific and are not uniformly beneficial. [ABSTRACT FROM AUTHOR]

Background: Peritoneal dialysis (PD) is an easily implementable dialysis modality in end-stage renal disease (ESRD). PD may improve access to renal replacement therapy in low- and middle-income countries; however, these countries have a higher prevalence of protein-energy wasting in patients and poorer socioeconomic conditions. We evaluated the effects of HIV infection on serum albumin levels in ESRD patients starting continuous ambulatory PD (CAPD) and mortality outcomes. Methods: We conducted a single-center prospective cohort study of consecutive incident CAPD patients recruited from two hospitals in Durban, South Africa, from September 2012 to February 2015. Seventy HIV-negative and 70 HIV-positive ESRD patients were followed monthly for serum albumin levels and mortality events during the first 18 months of CAPD therapy. Results: The HIV-positive cohort recorded 28 deaths (40%) among patients with a functional CAPD catheter at 18 months and 13 deaths (18.6%) in the HIV-negative cohort (p = 0.005). The mean serum albumin levels were lower in the HIV-positive cohort than in the HIV-negative cohort during the 18-month follow-up. The mean difference in serum albumin levels between the two cohorts was 4.24 g/L (95% confidence interval [CI] 2.02–6.46, p<0.001) at baseline and 3.99 g/L (95% CI 1.19–6.79, p = 0.006) at 18 months. HIV-positive status (adjusted regression coefficient -2.84, CI -5.00–-0.67, p = 0.011), diabetes (adjusted coefficient -2.85; CI, -5.58–-0.12; p = 0.041), and serum C-reactive protein and blood hemoglobin levels were independent predictors of serum albumin levels on multivariable linear regression. Baseline serum albumin <25 g/L (subdistribution-hazard ratio [SHR] 13.06, 95% CI 3.09–55.14, p<0.001) and CD4+ cell count <200 cells/μL (SHR 3.2, CI 1.38–7.45, p = 0.007) were independent predictors of mortality in our competing risk model. Conclusions: HIV infection can adversely affect serum albumin levels in ESRD patients managed with CAPD, while low baseline serum albumin levels and impaired immunity reliably predict mortality. [ABSTRACT FROM AUTHOR]

Background: We describe CD4 count recovery among HIV positive individuals who initiated antiretroviral therapy (ART) with and without severe immune suppression using complete laboratory data from South Africa’s national HIV treatment programme between 2010 and 2014 and discuss implications for CD4 count monitoring. Methods: Retrospective analysis of routinely collected laboratory data from South Africa’s National Health Laboratory Service (NHLS). A probabilistic record linkage algorithm was used to create a cohort of HIV positive individuals who initiated ART between 2010 and 2014 based on timing of CD4 count and viral load measurements. A CD4 count < 50 copies/μl at ART initiation was considered severe immunosuppression. A multivariable piecewise mixed-effects linear regression model adjusting for age, gender, year of starting ART, viral suppression in follow up and province was used to predict CD4 counts during follow up. Results: 1,070,900 individuals had evidence of starting ART during 2010–2014 and met the criteria for inclusion in the cohort -46.6% starting ART with CD4 < 200 cells/μl and 10.1% with CD4 < 50 cells/ μl. For individuals with CD4 counts < 200 cells/μl, predicted CD4 counts > 200 cells/μl, >350 cells/μl and >500 cells/μl corresponded with mean follow up durations of 1.5 years (standard deviation [s.d] 1.1), 1.9years (s.d 1.2) and 2.1 years (s.d 1.3 years). For those with CD4 counts < 50 cells/μl, predicted CD4 count above these threshold corresponded with mean follow up durations of 2.5 years (s.d 0.9 years), 4.4 years (s.d 0.4 years) and 5.0 years (s.d 0.1years) for recovery to the same thresholds. CD4 count recovery varied mostly with duration on ART, CD4 count at the start of ART and gender. Conclusion: For individuals starting with ART with severe immunosuppression, CD4 recovery to 200cells/μl did not occur or took longer than 12 month for significant proportions. CD4 monitoring and interventions recommended for advanced HIV disease should continue until full recovery. [ABSTRACT FROM AUTHOR]

Bacterial communities in human-impacted rivers and streams are exposed to multiple anthropogenic contaminants, which can eventually lead to biodiversity loss and function. The Wonderfonteinspruit catchment area is impacted by operational and abandoned gold mines, farms, and formal and informal settlements. In this study, we used 16S rRNA gene high-throughput sequencing to characterize bacterial communities in the lower Wonderfonteinspruit and their response to various contaminant sources. The results showed that composition and structure of bacterial communities differed significantly (P<0.05) between less (downstream) and more (upstream) polluted sites. The taxonomic and functional gene dissimilarities significantly correlated with each other, while downstream sites had more distinct functional genes. The relative abundance of Proteobacteria, Bacteroidetes and Actinobacteria was higher at upstream sites, while Acidobacteria, Cyanobacteria, Firmicutes and Verrucomicrobia were prominent at downstream sites. In addition, upstream sites were rich in genera pathogenic and/or potentially pathogenic to humans. Multivariate and correlation analyses suggest that bacterial diversity was significantly (P<0.05) impacted by pH and heavy metals (cobalt, arsenic, chromium, nickel and uranium). A significant fraction (~14%) of the compositional variation was explained by a combination of anthropogenic inputs, of which mining (~6%) was the main contributor to bacterial community variation. Network analysis indicated that bacterial communities had non-random inter- and intra-phyla associations and that the main taxa showed both positive and negative linkages to environmental parameters. Our results suggest that species sorting, due to environmental parameters, was the main process that structured bacterial communities. Furthermore, upstream sites had higher relative abundances of genes involved in xenobiotic degradation, suggesting stronger removal of polycyclic aromatic hydrocarbons and other organic compounds. This study provides insights into the influences of anthropogenic land use on bacterial community structure and functions in the lower Wonderfonteinspruit. [ABSTRACT FROM AUTHOR]

Introduction: Osteoporosis (OP) risk factor assessment and bone mineral density (BMD) testing are frequently omitted at baseline in aromatase inhibitor (AI) studies, which may lead to misinterpretation of AI associated bone loss. The present study describes bone health of South African postmenopausal women of predominantly Mixed Ancestry, prior to AI treatment. Methods: This descriptive baseline study, nested in a prospective AI cohort study, included postmenopausal women with endocrine sensitive breast cancer, aged 50 to 80 years. A baseline questionnaire documented demographic-, medical-, lifestyle- and fracture history. Body weight was assessed clinically, and body composition and BMD measured via dual energy absorptiometry (DXA). Data was analysed in STATA 14 using descriptive and inferential statistics. Results: 101 participants were recruited, with a mean age of 61±7 years. Nearly a third (n = 32) of women at baseline fulfilled global criteria for bone protection (BMD T-score ≥-2SD (n = 18); BMD T-score -1.5SD to < -2SD with risk factors (n = 14). Lower body weight, body mass index (BMI), fat mass index and lean mass index were significantly associated with the participants with a BMD measurement in keeping with a diagnosis of OP (p <0.001). Low vitamin D was present in 93% of the cohort tested (n = 95), whilst deficient vitamin D status (<20ng/ml) was documented in 52 women (55%). Conclusions: In this study, a third of postmenopausal women considered for AI therapy fulfilled international criteria for bone protective pharmacological intervention. This emphasizes the need for clinical risk and BMD assessment in postmenopausal breast cancer patients at baseline. Body composition and bone health associations highlight bone fragility associated with lower body weight. [ABSTRACT FROM AUTHOR]

A new Curriculum and Assessment Policy Statement (CAPS) was introduced in South Africa in 2012 to, among others, drive a learner-centred and constructivist approach to practical work in the high school subject Physical Sciences. This study investigates teachers' concerns with the implementation of practical work in Physical Sciences. A survey of 81 high school physical science teachers' concerns was conducted in a school district in South Africa. Participants were selected from 52 schools by means of convenience sampling. The seven stage concerns-based adoption model was used to identify teachers' stages of concern on the practical component of CAPS. The findings indicate that 69% of the participants (n = 47) had management concerns of high significance (p = 0.51), while the collaboration and consequence concerns were only slightly significant (p = 0.96). With regards to CAPS experience, respondents who had been implementing CAPS for less than three years had more personal concerns compared with those who had been executing it for three to four years. Equally, respondents with less experience with CAPS had marginally more management concerns compared with respondents with more experience. These trends were also observed with the collaboration and refocusing concerns suggesting that teachers with less CAPS experience worry more about their ability to manage practical work and to make laboratory activities workable in their contexts. The paper concludes with a discussion on the variety of concerns and how these might be addressed through targeted teacher professional development support. [ABSTRACT FROM AUTHOR]

Many countries, including South Africa, have implemented population-based household surveys to estimate HIV prevalence and the burden of HIV infection. Most household HIV surveys are designed to provide reliable estimates down to only the first subnational geopolitical level which, in South Africa, is composed of nine provinces. However HIV prevalence estimates are needed down to at least the second subnational level in order to better target the delivery of HIV care, treatment and prevention services. The second subnational level in South Africa is composed of 52 districts. Achieving adequate precision at the second subnational level therefore requires either a substantial increase in survey sample size or use of model-based estimation capable of incorporating other pre-existing data. Our purpose is demonstration of the efficacy of relatively simple small-area estimation of HIV prevalence in the 52 districts of South Africa using data from the South African National HIV Prevalence, Incidence and Behavior Survey, 2012, district-level HIV prevalence estimates obtained from testing of pregnant women who attended antenatal care (ANC) clinics in 2012, and 2012 demographic data. The best-fitting model included only ANC prevalence and dependency ratio as out-of-survey predictors. Our key finding is that ANC prevalence was the superior auxiliary covariate, and provided substantially improved precision in many district-level estimates of HIV prevalence in the general population. Inclusion of a district-level spatial simultaneously autoregressive covariance structure did not result in improved estimation. [ABSTRACT FROM AUTHOR]

This study explored teachers' experiences in the teaching of electricity and magnetism during a Lesson Study intervention. Using a case study research design, a sample of 4 physical sciences teachers was conveniently selected from schools in rural and suburban areas. Due to logistical challenges, the 4 participants were grouped into 2 separately functioning lesson study pairs. Data were collected through multiple sources including semi-structured interviews, observations of classroom teaching and Lesson Study meetings, field notes, participants' initial lesson plans and reflective writings. It was found that collaboration through Lesson Study enhanced teachers' professional teaching strategies, networking skills, lesson plan writing, classroom management, self-efficacy and positive attitudes towards teaching. However, challenges such as lack of time, lack of institutional support and insufficient instructional materials pose a threat to teachers' participation in Lesson Study. It is therefore recommended that policy makers develop strategic plans to promote the use of Lesson Study as a school-based professional development initiative. Further research on Lesson Study in pre-service science teacher education may pave the way towards professional collaboration as a sustainable practice amongst science teachers. This may ultimately improve the performance levels of science learners in South Africa. [ABSTRACT FROM AUTHOR]

Howiesons Poort (HP) sites, over the past decades, have provided exceptional access to anthropogenic remains that are enhancing our understanding of early modern human behaviour during the Middle Stone Age in southern Africa. Here, we analyse the technological and typological trends in the lithic record that form part of these behaviours, based on the HP sequence recently excavated at Klipdrift Shelter, located on the southern Cape coast of South Africa. This study contributes to enhance knowledge on the mechanisms of changes that occurred during the transition to the post-HP. Despite patterns of continuity observed, notably for core reduction methods, the seven successive lithic assemblages show significant changes in the typological characteristics and raw material selection but also in the relative importance of blade production over time. However, these changes are not necessarily synchronic and occur either as gradual processes or as abrupt technological shifts. Consequently, we cross-examine the association between the lithic phasing and other anthropogenic remains within the HP sequence at Klipdrift Shelter. We explore the implications of these patterns of changes in terms of cultural behaviours and population dynamics during the HP and we highlight the relationship between the different phases of the HP sequence at Klipdrift Shelter and those from other South African HP sites. [ABSTRACT FROM AUTHOR]

The article examines the effectiveness of sequential aerosol technique (SAT) against riverine tsetse flies in southern Africa. An overview on the tuning control operations concerning the reproduction of tsetse flies, is highlighted. Also emphasized are the tsetse species' challenging habitats in the adaptation of SAT, is also emphasized.

In the past few decades, a diverse array of research has emphasized the precocity of technically advanced and symbolic practices occurring during the southern African Middle Stone Age. However, uncertainties regarding the regional chrono-cultural framework constrain models and identification of the cultural and ecological mechanisms triggering the development of such early innovative behaviours. Here, we present new results and a refined chronology for the Pietersburg, a techno-complex initially defined in the late 1920’s, which has disappeared from the literature since the 1980’s. We base our revision of this techno-complex on ongoing excavations at Bushman Rock Shelter (BRS) in Limpopo Province, South Africa, where two Pietersburg phases (an upper phase called ‘21’ and a lower phase called ‘28’) are recognized. Our analysis focuses on the ‘28’ phase, characterized by a knapping strategy based on Levallois and semi-prismatic laminar reduction systems and typified by the presence of end-scrapers. Luminescence chronology provides two sets of ages for the upper and lower Pietersburg of BRS, dated respectively to 73±6ka and 75±6ka on quartz and to 91±10ka and 97±10ka on feldspar, firmly positioning this industry within MIS5. Comparisons with other published lithic assemblages show technological differences between the Pietersburg from BRS and other southern African MIS5 traditions, especially those from the Western and Eastern Cape. We argue that, at least for part of MIS5, human populations in South Africa were regionally differentiated, a process that most likely impacted the way groups were territorially and socially organized. Nonetheless, comparisons between MIS5 assemblages also indicate some typological similarities, suggesting some degree of connection between human groups, which shared similar innovations but manipulated them in different ways. We pay particular attention to the end-scrapers from BRS, which represent thus far the earliest documented wide adoption of such tool-type and provide further evidence for the innovative processes characterizing southern Africa from the MIS5 onwards. [ABSTRACT FROM AUTHOR]

Background: South Africa has undergone multiple expansions in antiretroviral therapy (ART) eligibility from an initial CD4+ threshold of ≤200 cells/μl to providing ART for all people living with HIV (PLWH) as of September 2016. We evaluated the association of programmatic changes in ART eligibility with loss from care, both prior to ART initiation and within the first 16 weeks of starting treatment, during a period of programmatic expansion to ART treatment at CD4+ ≤ 350 cells/μl.Methods and Findings: We performed a retrospective cohort study of 4,025 treatment-eligible, non-pregnant PLWH accessing care in a community health center in Gugulethu Township affiliated with the Desmond Tutu HIV Centre in Cape Town. The median age of participants was 34 years (IQR 28-41 years), almost 62% were female, and the median CD4+ count was 173 cells/μl (IQR 92-254 cells/μl). Participants were stratified into 2 cohorts: an early cohort, enrolled into care at the health center from 1 January 2009 to 31 August 2011, when guidelines mandated that ART initiation required CD4+ ≤ 200 cells/μl, pregnancy, advanced clinical symptoms (World Health Organization [WHO] stage 4), or comorbidity (active tuberculosis); and a later cohort, enrolled into care from 1 September 2011 to 31 December 2013, when the treatment threshold had been expanded to CD4+ ≤ 350 cells/μl. Demographic and clinical factors were compared before and after the policy change using chi-squared tests to identify potentially confounding covariates, and logistic regression models were used to estimate the risk of pre-treatment (pre-ART) loss from care and early loss within the first 16 weeks on treatment, adjusting for age, baseline CD4+, and WHO stage. Compared with participants in the later cohort, participants in the earlier cohort had significantly more advanced disease: median CD4+ 146 cells/μl versus 214 cells/μl (p < 0.001), 61.1% WHO stage 3/4 disease versus 42.8% (p < 0.001), and pre-ART mortality of 34.2% versus 16.7% (p < 0.001). In total, 385 ART-eligible PLWH (9.6%) failed to initiate ART, of whom 25.7% died before ever starting treatment. Of the 3,640 people who started treatment, 58 (1.6%) died within the first 16 weeks in care, and an additional 644 (17.7%) were lost from care within 16 weeks of starting ART. PLWH who did start treatment in the later cohort were significantly more likely to discontinue care in <16 weeks (19.8% versus 15.8%, p = 0.002). After controlling for baseline CD4+, WHO stage, and age, this effect remained significant (adjusted odds ratio [aOR] = 1.30, 95% CI 1.09-1.55). As such, it remains unclear if early attrition from care was due to a "healthy cohort" effect or to overcrowding as programs expanded to accommodate the broader guidelines for treatment. Our findings were limited by a lack of generalizability (given that these data were from a single high-volume site where testing and treatment were available) and an inability to formally investigate the effect of crowding on the main outcome.Conclusions: Over one-quarter of this ART-eligible cohort did not achieve the long-term benefits of treatment due to early mortality, ART non-initiation, or early ART discontinuation. Those who started treatment in the later cohort appeared to be more likely to discontinue care early, and this outcome appeared to be independent of CD4+ count or WHO stage. Future interventions should focus on those most at risk for early loss from care as programs continue to expand in South Africa. [ABSTRACT FROM AUTHOR]

Background: Prenatal exposure to lead (Pb) has been shown to have negative and irreversible health impacts on foetal and early childhood development, affecting morbidity and mortality in adulthood. This study aimed to assess in utero Pb exposure, examine birth outcomes, and identify confounding factors in the large cohort of South African population, following the legislated removal of Pb from petrol. Methods: Lead was measured in the maternal blood, urine and cord blood using Inductive Coupled Plasma Mass spectrometry (ICP-MS). The statistical analyses included Spearman’s correlation, Wilcoxon rank sum (Mann Whitney), Kruskal-Wallis rank tests and multivariate linear regression. Results: Overall, the geometric mean (GM) of Pb in maternal blood (PbB) was 1.32 μg/dL (n = 640; 95% CI, 1.24–1.40). In the subset cohort, the GM of paired maternal PbB and cord blood (PbC) was 1.73 μg/dL (n = 350; 95% CI, 1.60–1.86) and 1.26 μg/dL (n = 317; 95% CI, 1.18–1.35), respectively with a positive correlation between the log PbB and the log PbC (rho = 0.65, p = <0.001). Birth outcomes showed geographical differences in the gestational age (p<0.001), birth length (p = 0.028) and head circumference (p<0.001), Apgar score at 5 min (p<0.001) and parity (p<0.002). In female neonates, a positive association was found between PbC and head circumference (rho = 0.243; p<0.016). The maternal PbB levels were positively correlated with race, educational status, water sources, cooking fuels and use of pesticides at home. Conclusions: This study has demonstrated not only the positive impact that the introduction of unleaded petrol and lead-free paint has had on in utero exposure to Pb in South Africa, but has also contributed new data on the topic, in a region where such data and scientific investigations in this field are lacking. Future research should evaluate if similar effects can be detected in young children and the adult population. [ABSTRACT FROM AUTHOR]

Southern African protected areas (PAs) harbour a great diversity of animals, which represent a large potential for wildlife tourism. In this region, global change is expected to result in vegetation changes, such as bush encroachment and increases in vegetation density. However, little is known on the influence of vegetation structure on wildlife tourists’ wildlife viewing experience and satisfaction. In this study, we collected data on vegetation structure and perceived mammal densities along 196 road transects (each 5 km long) and conducted a social survey with 651 questionnaires across four PAs in three Southern African countries. Our objectives were 1) to assess visitors’ attitude towards vegetation, 2) to test the influence of perceived mammal density and vegetation structure on the easiness to spot animals, and 3) on visitors’ satisfaction during their visit to PAs. Using a Boosted Regression Tree procedure, we found mostly negative non-linear relationships between vegetation density and wildlife tourists’ experience, and positive relationships between perceived mammal densities and wildlife tourists’ experience. In particular, wildlife tourists disliked road transects with high estimates of vegetation density. Similarly, the easiness to spot animals dropped at thresholds of high vegetation density and at perceived mammal densities lower than 46 individuals per road transect. Finally, tourists’ satisfaction declined linearly with vegetation density and dropped at mammal densities smaller than 26 individuals per transect. Our results suggest that vegetation density has important impacts on tourists’ wildlife viewing experience and satisfaction. Hence, the management of PAs in savannah landscapes should consider how tourists perceive these landscapes and their mammal diversity in order to maintain and develop a sustainable wildlife tourism. [ABSTRACT FROM AUTHOR]

The population density of wildlife reservoirs contributes to disease transmission risk for domestic animals. The objective of this study was to model the African buffalo distribution of the Kruger National Park. A secondary objective was to collect field data to evaluate models and determine environmental predictors of buffalo detection. Spatial distribution models were created using buffalo census information and archived data from previous research. Field data were collected during the dry (August 2012) and wet (January 2013) seasons using a random walk design. The fit of the prediction models were assessed descriptively and formally by calculating the root mean square error (rMSE) of deviations from field observations. Logistic regression was used to estimate the effects of environmental variables on the detection of buffalo herds and linear regression was used to identify predictors of larger herd sizes. A zero-inflated Poisson model produced distributions that were most consistent with expected buffalo behavior. Field data confirmed that environmental factors including season (P = 0.008), vegetation type (P = 0.002), and vegetation density (P = 0.010) were significant predictors of buffalo detection. Bachelor herds were more likely to be detected in dense vegetation (P = 0.005) and during the wet season (P = 0.022) compared to the larger mixed-sex herds. Static distribution models for African buffalo can produce biologically reasonable results but environmental factors have significant effects and therefore could be used to improve model performance. Accurate distribution models are critical for the evaluation of disease risk and to model disease transmission. [ABSTRACT FROM AUTHOR]

Background: In low resource settings, an inadequate number of trained healthcare workers and high volumes of children presenting to Primary Healthcare Centers (PHC) result in prolonged waiting times and significant delays in identifying and evaluating critically ill children. The Sick Children Require Emergency Evaluation Now (SCREEN) program, a simple six-question screening algorithm administered by lay healthcare workers, was developed in 2014 to rapidly identify critically ill children and to expedite their care at the point of entry into a clinic. We sought to determine the impact of SCREEN on waiting times for critically ill children post real world implementation in Cape Town, South Africa. Methods and findings: This is a prospective, observational implementation-effectiveness hybrid study that sought to determine: (1) the impact of SCREEN implementation on waiting times as a primary outcome measure, and (2) the effectiveness of the SCREEN tool in accurately identifying critically ill children when utilised by the QM and adherence by the QM to the SCREEN algorithm as secondary outcome measures. The study was conducted in two phases, Phase I control (pre-SCREEN implementation- three months in 2014) and Phase II (post-SCREEN implementation—two distinct three month periods in 2016). In Phase I, 1600 (92.38%) of 1732 children presenting to 4 clinics, had sufficient data for analysis and comprised the control sample. In Phase II, all 3383 of the children presenting to the 26 clinics during the sampling time frame had sufficient data for analysis. The proportion of critically ill children who saw a professional nurse within 10 minutes increased tenfold from 6.4% to 64% (Phase I to Phase II) with the median time to seeing a professional nurse reduced from 100.3 minutes to 4.9 minutes, (p < .001, respectively). Overall layperson screening compared to Integrated Management of Childhood Illnesses (IMCI) designation by a nurse had a sensitivity of 94.2% and a specificity of 88.1%, despite large variance in adherence to the SCREEN algorithm across clinics. Conclusions: The SCREEN program when implemented in a real-world setting can significantly reduce waiting times for critically ill children in PHCs, however further work is required to improve the implementation of this innovative program. [ABSTRACT FROM AUTHOR]

Heat treatment was one of the first transformative technologies in the southern African Middle Stone Age (MSA), with many studies in the Cape coastal zone of South Africa identifying it as an essential step in the preparation of silcrete prior to its use in stone tool manufacture. To date, however, no studies have investigated whether heat treatment is necessary for all silcrete types, and how geographically widespread heat treatment was in the subcontinent. The aim of this study is to investigate experimentally whether heat treatment continued further north into the Kalahari Desert of Botswana and northernmost South Africa, the closest area with major silcrete outcrops to the Cape. For this we analyse the thermal transformations of silcrete from both regions, proposing a comprehensive model of the chemical, crystallographic and ‘water’-related processes taking place upon heat treatment. For the first time, we also explore the mobility of minor and trace elements during heat treatment and introduce a previously undescribed mechanism—steam leaching—causing depletion of a limited number of elements. The results of this comparative study reveal the Cape and Kalahari silcrete to respond fundamentally differently to heat treatment. While the former can be significantly improved by heat, the latter is deteriorated in terms of knapping quality. These findings have important implications for our understanding of the role of fire as a technical solution in MSA stone tool knapping, and for the extension of its use in southern Africa. Silcrete heat treatment—at least in the form we understand it today—may have been a strictly regional phenomenon, confined to a narrow zone along the west and south coast of the Cape. On the basis of our findings, silcrete heat treatment should not be added as a new trait on the list of behaviours that characterise the MSA of the southern African subcontinent. [ABSTRACT FROM AUTHOR]

Africa remains the most cholera stricken continent in the world as many people lacking access to safe drinking water rely mostly on polluted rivers as their main water sources. However, studies in these countries investigating the presence of Vibrio cholerae in aquatic environments have paid little attention to bed sediments. Also, information on the presence of virulence-associated genes (VAGs) in environmental ctx-negative V. cholerae strains in this region is lacking. Thus, we investigated the presence of V. cholerae VAGs in water and riverbed sediment of the Apies River, South Africa. Altogether, 120 samples (60 water and 60 sediment samples) collected from ten sites on the river (January and February 2014) were analysed using PCR. Of the 120 samples, 37 sediment and 31 water samples were positive for at least one of the genes investigated. The haemolysin gene (hlyA) was the most isolated gene. The cholera toxin (ctxAB) and non-O1 heat-stable (stn/sto) genes were not detected. Genes were frequently detected at sites influenced by human activities. Thus, identification of V. cholerae VAGs in sediments suggests the possible presence of V. cholerae and identifies sediments of the Apies River as a reservoir for potentially pathogenic V. cholerae with possible public health implications. [ABSTRACT FROM AUTHOR]

TB is rated as one of the world’s deadliest diseases and South Africa ranks 9th out of the 22 countries with hardest hit of TB. Although many pieces of research have been carried out on this subject, this paper steps further by inculcating past knowledge into the model, using Bayesian approach with informative prior. Bayesian statistics approach is getting popular in data analyses. But, most applications of Bayesian inference technique are limited to situations of non-informative prior, where there is no solid external information about the distribution of the parameter of interest. The main aim of this study is to profile people living with TB in South Africa. In this paper, identical regression models are fitted for classical and Bayesian approach both with non-informative and informative prior, using South Africa General Household Survey (GHS) data for the year 2014. For the Bayesian model with informative prior, South Africa General Household Survey dataset for the year 2011 to 2013 are used to set up priors for the model 2014. [ABSTRACT FROM AUTHOR]

Carbon isotope analysis of four baobab (Adansonia digitata L.) trees from the Pafuri region of South Africa yielded a 1000-year proxy rainfall record. The Pafuri record age model was based on 17 radiocarbon dates, cross correlation of the climate record, and ring structures that were presumed to be annual for two of the trees. Here we present the analysis of five additional baobabs from the Mapungubwe region, approximately 200km west of Pafuri. The Mapungubwe chronology demonstrates that ring structures are not necessarily annually formed, and accordingly the Pafuri chronology is revised. Changes in intrinsic water-use efficiency indicate an active response by the trees to elevated atmospheric CO2, but this has little effect on the environmental signal. The revised Pafuri record, and the new Mapungubwe record correlate significantly with local rainfall. Both records confirm that the Medieval Warm Period was substantially wetter than present, and the Little Ice Age was the driest period in the last 1000 years. Although Mapungubwe is generally drier than Pafuri, both regions experience elevated rainfall peaking between AD 1570 and AD 1620 after which dry conditions persist in the Mapungubwe area until about AD 1840. Differences between the two records correlate with Agulhas Current sea-surface temperature variations suggesting east/west displacement of the temperate tropical trough system as an underlying mechanism. The Pafuri and Mapungubwe records are combined to provide a regional climate proxy record for the northern summer rainfall area of southern Africa. [ABSTRACT FROM AUTHOR]

Rapid diagnostic tools have been shown to improve linkage of patients to care. In the context of infectious diseases, assessing the impact and cost-effectiveness of such tools at the population level, accounting for both direct and indirect effects, is key to informing adoption of these tools. Point-of-care (POC) CD4 testing has been shown to be highly effective in increasing the proportion of HIV positive patients who initiate ART. We assess the impact and cost-effectiveness of introducing POC CD4 testing at the population level in South Africa in a range of care contexts, using a dynamic compartmental model of HIV transmission, calibrated to the South African HIV epidemic. We performed a meta-analysis to quantify the differences between POC and laboratory CD4 testing on the proportion linking to care following CD4 testing. Cumulative infections averted and incremental cost-effectiveness ratios (ICERs) were estimated over one and three years. We estimated that POC CD4 testing introduced in the current South African care context can prevent 1.7% (95% CI: 0.4% - 4.3%) of new HIV infections over 1 year. In that context, POC CD4 testing was cost-effective 99.8% of the time after 1 year with a median estimated ICER of US$4,468/DALY averted. In healthcare contexts with expanded HIV testing and improved retention in care, POC CD4 testing only became cost-effective after 3 years. The results were similar when, in addition, ART was offered irrespective of CD4 count, and CD4 testing was used for clinical assessment. Our findings suggest that even if ART is expanded to all HIV positive individuals and HIV testing efforts are increased in the near future, POC CD4 testing is a cost-effective tool, even within a short time horizon. Our study also illustrates the importance of evaluating the potential impact of such diagnostic technologies at the population level, so that indirect benefits and costs can be incorporated into estimations of cost-effectiveness. [ABSTRACT FROM AUTHOR]

Background: Interventions to prevent rape perpetration must be designed to address its drivers. This paper seeks to extend understanding of drivers of single and multiple perpetrator rape (referred to here as SPR and MPR respectively) and the relationships between socio-economic status, childhood trauma, peer pressure, other masculine behaviours and rape. Method: 1370 young men aged 15 to 26 were interviewed as part of the randomised controlled trial evaluation of Stepping Stones in the rural Eastern Cape. We used multinomial to compare the characteristics of men who reported rape perpetration at baseline. We used structural equation modelling (SEM) to examine pathways to rape perpetration. Results: 76.1% of young men had never raped, 10.0% had perpetrated SPR and 13.9% MPR. The factors associated with both MPR and SPR (compared to never having raped) were indicators of socio-economic status (SES), childhood trauma, sexual coercion by a woman, drug and alcohol use, peer pressure susceptibility, having had transactional sex, multiple sexual partners and being physically violent towards a partner. The SEM showed the relationship between SES and rape perpetration to be mediated by gender inequitable masculinity. It was complex as there was a direct path indicating that SES correlated with the masculinity variable directly such that men of higher SES had more gender inequitable masculinities, and indirect path mediated by peer pressure resistance indicated that the former pertained so long as men lacked peer pressure resistance. Having a higher SES conveyed greater resistance for some men. There was also a path mediated through childhood trauma, such that men of lower SES were more likely to have a higher childhood trauma exposure and this correlated with a higher likelihood of having the gender inequitable masculinity (with or without the mediating effect of peer pressure resistance). Discussion: Both higher and lower socio-economic status were associated with raping. Prevention of rape perpetration must focus on changing men’s gender ideals, entitlements and inequitable practices. Reducing poverty and adverse childhood experiences should also be of benefit. [ABSTRACT FROM AUTHOR]

Introduction: Pulmonary tuberculosis (TB) remains a major public health challenge in South Africa. However, little attention is paid to the impact of health related quality of life (HRQL) among TB patients at the beginning and at the end of TB treatment. This study assesses factors associated with HRQL among tuberculosis patients in three high risk provinces in South Africa. Methods: A prospective cohort study was conducted at primary health care settings. Patients completed the HRQL social functioning (SF)-12 health survey. Comparison of Physical Health Summary Score (PCS) and Mental Health Summary Score (MCS) was assessed at 6 months after treatment. Generalized estimating equations (GEEs) were used to examine the factors associated with changes in HRQL. Results: In all patients, after 6 months of treatment there was a significant improvement in HRQL with the biggest increase in the PCS. A higher educational qualification had a strong significant positive effect on the mental HRQL. Psychological distress showed a significant negative association with physical and mental HRQL after six months. Permanent residence showed a significant positive association with mental HRQL among TB patients compared to those living in shack/traditional dwellings. Rating ones health as being good and fair/poor was significantly associated with poor physical HRQL. Twenty drinks or more in the past month had a significant negative effect on the physical HRQL. Conclusion: The findings suggest that programmes targeted at improving TB treatment success should have specific interventions for patients with low educational background, impoverished households/communities and those with hazardous or harmful alcohol use. [ABSTRACT FROM AUTHOR]

Background: HIV-exposed uninfected (HEU) infants are a growing population in sub-Saharan Africa especially with the increasing coverage of more effective prevention of mother-to-child transmission (PMTCT) antiretroviral therapy regimens. This study describes the characteristics of South African HEU infants, investigates factors impacting birth weight and assesses their growth within the first 28 weeks of life. Methods: This is a retrospective cohort based on routine clinical data from two South African PMTCT programmes. Data were collected between 2007 and 2013. Linear regression assessed factors affecting birth weight-for-age z-scores (WAZ) while growth (longitudinal WAZ) was assessed using mixed effects models. Results: We assessed the growth of 2621 HEU infants (median birth WAZ was -0.65 (IQR -1.46; 0.0) and 51% were male). The feeding modalities practised were as follows: 0.5% exclusive breastfeeding, 7.9% breastfeeding with unknown exclusivity, 0.08% mixed breastfeeding and 89.2% formula feeding. Mothers with CD4 <200 cells/μl delivered infants with a lower birth WAZ (adjusted ß -0.253 [95% CI -0.043; -0.072], p = 0.006) compared to mothers with aCD4 ≥500 cells/μl. Similarly, mothers who did not receive antiretroviral drugs delivered infants with a lower birth WAZ (adjusted ß -0.39 [95% CI -0.67; -0.11], p = 0.007) compared to mothers who received antenatal antiretrovirals. Infants with a birth weight <2 500g (ß 0.070 [95% CI 0.061; 0.078], p <0.0001) experienced faster growth within the first 28 weeks of life compared to infants with a birth weight ≥2 500g. Infants with any breastfeeding exposure experienced slower longitudinal growth compared to formula fed infants (adjusted ß -0.012 [95% CI 0.021; -0.003], p = 0.011). Conclusion: Less severe maternal disease and the use of antiretrovirals positively impacts birth weight in this cohort of South African HEU infants. Formula feeding was common with breastfed infants experiencing marginally slower longitudinal growth. [ABSTRACT FROM AUTHOR]

Understanding HIV transmission dynamics is critical to estimating the potential population-wide impact of HIV prevention and treatment interventions. We developed an individual-based simulation model of the heterosexual HIV epidemic in South Africa and linked it to the previously published Cost-Effectiveness of Preventing AIDS Complications (CEPAC) International Model, which simulates the natural history and treatment of HIV. In this new model, the CEPAC Dynamic Model (CDM), the probability of HIV transmission per sexual encounter between short-term, long-term and commercial sex worker partners depends upon the HIV RNA and disease stage of the infected partner, condom use, and the circumcision status of the uninfected male partner. We included behavioral, demographic and biological values in the CDM and calibrated to HIV prevalence in South Africa pre-antiretroviral therapy. Using a multi-step fitting procedure based on Bayesian melding methodology, we performed 264,225 simulations of the HIV epidemic in South Africa and identified 3,750 parameter sets that created an epidemic and had behavioral characteristics representative of a South African population pre-ART. Of these parameter sets, 564 contributed 90% of the likelihood weight to the fit, and closely reproduced the UNAIDS HIV prevalence curve in South Africa from 1990–2002. The calibration was sensitive to changes in the rate of formation of short-duration partnerships and to the partnership acquisition rate among high-risk individuals, both of which impacted concurrency. Runs that closely fit to historical HIV prevalence reflect diverse ranges for individual parameter values and predict a wide range of possible steady-state prevalence in the absence of interventions, illustrating the value of the calibration procedure and utility of the model for evaluating interventions. This model, which includes detailed behavioral patterns and HIV natural history, closely fits HIV prevalence estimates. [ABSTRACT FROM AUTHOR]

The main purpose of this study was to identify alternative conceptions held by high school learners concerning mechanics, as one of the major topics in South Africa's NCS. The research sample comprised 140 grade 12 students from four high schools. A researcher-designed test was used to collect the required data. Although quantitative data were collected, the main thrust of data analysis for this paper was on the qualitative data generated. The results showed that the students mainly held eight alternative conceptions related to mechanics. These were that (a) the velocity and acceleration of a projectile increase as the projectile goes up; (b) the weight, or mass, of an object has an effect on the magnitude of the force it exerts; (c) force is needed to keep an object moving at all times, (d) only active agents exert force; (e) objects that are not moving do not exert force; (f) action-reaction forces occur at different times.; (g) at the highest point, the acceleration of a projectile is zero; and (h) motion implies active force. These findings are discussed, and recommendations made. [ABSTRACT FROM AUTHOR]

The article offers the author's insights regarding the conversations in South Africa related to diverse artistic and cultural heritages that motivated a set of questions which is significant part of reconstituting and rethinking humanities. He says that they found their selves withdrawing in ways of thinking on humanities that have formed its present institutional character. He adds that humanities provides new paths to negotiate the terrain between arts and physical and natural sciences.

Plans are well advanced for converting disused railway carriages into travelling science classrooms, laboratories, and an exhibition centre in the form of a Science and Technology (S&T) Train that will travel to the deep rural areas of South Africa. This multimillion rand educational resource will focus initially on promoting the geosciences and their applications, providing on hoard expertise in teaching and in the conduct of research, supported by the necessary technical equipment and the experts on board. It is also intended to reach out to and create science awareness among the young and their parents who live on its route: for undergraduate and postgraduate training; as a source of advice on social services; as a contributor to economic development; and as an adjunct to international research programmes. The S&T Train is also to be a vehicle for training first-degree students at technical universities in particular, allowing them to obtain the experiential learning that is a prerequisite for them to graduate. Also featuring on the train's agenda is problem solving associated with rural daily life, such as the provision of clean drinking water, the search for sources of local building materials and assistance with appropriate placement of waste sites. Redundant rolling stock donated by Transnet Freight Rail is currently being refurbished for its new role. road the project will be managed by the Tshwane Institute for Advanced Studies at Tshwane University of Technology in Pretoria, with Support from the Department of Science and Technology and other government departments. [ABSTRACT FROM AUTHOR]

I report on an analysis of the alignment between the South African Grade 12 Physical Sciences core curriculum content and the exemplar papers of 2008, and the final examination papers of 2008 and 2009. A two-dimensional table was used for both the curriculum and the examination in order to calculate the Porter alignment index, which indicates the degree of match between the two. Alignment indices of 0.8 and 0.6 for Physics and Chemistry, respectively, were computed and remained constant for Physics, but fluctuated initially for Chemistry before levelling off. Using the revised Bloom's taxonomy, discrepancies were found in terms of cognitive levels as well as content areas in both Physics and Chemistry. The cognitive level Remember is under-represented in the Chemistry and Physics examinations, whereas the cognitive levels Understand and Apply were over-represented in Chemistry. It is argued that the shift to higher cognitive levels is in line with the reported increase in cognitive complexity of the Physical Sciences curriculum. The significance of the study for Physical Science teachers is highlighted, and the potential for further research is also indicated. [ABSTRACT FROM AUTHOR]

Computational physics as a university undergraduate programme, or as a choice of specialized modules or laboratories within the mainstream physics programme, has grown considerably over the past several years, but this trend is yet to develop fully in South Africa. This paper provides a motivation for developing computational physics at our universities and suggests how such a programme may be designed. We argue that students develop a more intuitive feel for physics, that they learn useful, transferable skills that make our graduates sought-after by industry and commerce, and that such graduates are better prepared to tackle research problems at the master's and doctoral levels both in theoretical and experimental physics. We also discuss current research topics in computational physics that are of relevance to South Africa. [ABSTRACT FROM AUTHOR]

Growth morphology appearing as external forms and zonal structures of spinel-twinned crystals of natural diamond from South Africa was studied. The crystals are divided into four groups depending upon the modification of their re-entrant corners by growth layers generated at the twin boundary. The flattened morphology is found to be caused by the preferential growth at both re-entrant and salient corners, the latter being revealed for the first time by this paper. The change of supersaturation conditions was also estimated from the morphological change. [Copyright &y& Elsevier]

Focuses on the differential roles of Physical Science and Biology in achieving scientific literacy among students at the secondary and tertiary levels using the Test of Basic Scientific Literacy (TSBL) in South Africa. Comparison of mean scores of Physical Science and Biology students for the TSBL; Mechanisms through which Physical Sciences affects the achievement of scientific literacy.

Discusses students' experience on the restructuring of the Introductory Physical Chemistry module at the University of South Africa in distance education. Assessment of students' performance in Physical Science at secondary level; Redesign of the study guide to cater to slow learners; Incorporation of students' feedback on the changes into the study guide.

The article discusses dangers faced by the physics discipline in South Africa. An international panel is concerned about potential dangers facing the discipline of physics in South Africa. South Africa has an impressive track record for a middle-order country in science. Apart from covering most bases in their discipline's pantheon at one time or another, physicists have made substantial contributions in diverse fields including ionospheric and cosmic-ray research, geochronology, geomagnetism, lightning and radar, crystal defects. A revised bursary scheme to encourage school-leavers to study and stay in physics have been recommended. The creation of a fast, inexpensive, broadband national research information network to support non-commercial research and the hub of a knowledge-based economy have also been proposed.

The article reports on the opening of two research centers, a pan-African center of the existing African Institute for Mathematical Sciences and the National Institute for Theoretical Physics, in Cape Town, South Africa in May 2008. The launching of the two research facility is a bid to support and strengthen theoretical physics and mathematical sciences across the continent. The research centers will be launched on May 12 and 13 respectively, and funded mainly by the South African Department of Science and Technology.

The article focuses on the results of a study by Thomassot and colleagues on nearly 60 diamonds that contained within one small mantle sample carried to the surface in a kimberlite volcano in South Africa. The chemistry of diamonds brought up from the Earth's mantle, notably their widely ranging nitrogen contents and nitrogen and carbon isotope values has complicated understanding of their origins. The nitrogen contents and isotopic values of the diamonds in the sample spanned a large part of the ranges observed from all diamonds worldwide.

The article reports that the South African Institute of Physics (SAIP) is using the occasion of its jubilee to enhance the standing and role of physics in the country. The institute's members are aware that, potential dangers face the discipline and physics has limited appeal among the current generation of school-leavers contemplating what to pursue as a career or what to study further. Indeed, that was a concern of an international panel whose assessment and recommendations to address this state of affairs in South Africa. In collaboration with the South African Department of Science and Technology, the National Research Foundation and other parties, the SAIP is now drawing up specific proposals and their associated costs to advance the discipline. Particular attention needs to be paid to the teaching of physics at school, both in terms of the future syllabus and support for teachers and in universities. Various flagship projects are being pursued. The astronomers, for example, with their minds focused on the opportunities created by the inauguration of the Southern African Large Telescope in November 2004, have been working on a Frontiers in Astronomy programme.