State-of-the-art review on energy sharing and trading of resilient multi microgrids.

Independently run single microgrids (MGs) encounter difficulties with inadequate self-consumption of local renewable energy and frequent power exchange with the grid. Combining numerous MGs to form a multi-microgrid (MMG) is a viable approach to enhance smart distribution networks' operational and financial performance. However, the correlation and coordination of intermittent power generation within each MG network pose many techno-economic challenges for energy sharing and trading. This review offers a comprehensive analysis of these challenges within the framework of MMG operations. It examines state-of-the-art methodologies for optimizing multi-energy dispatch and scrutinizes contemporary strategies within energy markets that contribute to the resilience of power systems. The discourse extends to the burgeoning role of blockchain technology in revolutionizing decentralized market frameworks and the intricacies of MMG coordination for reliable and cost-effective energy distribution. Overall, this study provides ample inspiration for theoretical and practical research to the new entrants and experts alike to develop new concepts for energy markets, scheduling and novel operating models for future resilient multi-energy networked systems/MMGs.

The academic progress of female general surgery and orthopaedic surgery trainees in South Africa.

BACKGROUND: Globally, medical institutes have seen an increase in female graduates, however surgical disciplines remain male-dominated. An epidemiological shift towards non-communicable diseases and trauma may result in a shortage of surgical specialists. One strategy to improve the surgical workforce is the recruitment of female graduates. METHODS: A non-validated questionnaire was administered to females registered for the Master of Medicine (MMED) degree in General and Orthopaedic Surgery at the University of KwaZulu-Natal (UKZN) between 2000 and 2015. The study evaluated reasons for choice of surgery as a career, challenges faced on the domestic and work front, as well as factors that assisted with successful completion of training. RESULTS: Seventy-two female trainees in General Surgery and Orthopaedics were identified from the UKZN databases. The contact details for 62 of these trainees were available. The overall response rate was 71.0% (44/62). A total of 95.5% (42/44) of participants selected surgery due to a passion for the field. Major challenges identified were a poor home and work-life balance (72.1%, 31/43) and poor working conditions (62.8%, 27/43). Female trainees perceived that they were viewed as inferior by patients (65.9%, 29/44). Successful trainees had a good home support system (89.3%, 25/28) and mentorship during training (60.7%, 17/28), and 85.7% (24/28) did not regret their career choice. CONCLUSION: The recruitment and retention of females in surgery will contribute to maintaining an adequate surgical workforce. Training programmes need to improve work-life balance without compromising on producing competent surgeons. Improved visibility of female surgeons in leadership roles should be encouraged to promote mentorship and recruitment of trainees.

The influence of psychological readiness of athletes when returning to sport after injury.

Background: Injuries are a common occurrence in sports participation; however, they have the potential to be accompanied by negative thoughts and feelings, which may play a part in the athletes' state of mind when they return to their sport. Assessing the degree to which this occurs provides an opportunity to evaluate and address athletes' state of mind before their return to play. Objectives: To determine if athletes are psychologically ready to return to play after an injury and if there are differences in fear avoidance behaviour between those who were and were not ready to return. Methods: Eighty-eight athletes participated in this descriptive survey. Athletes' confidence to return to play was measured by the Injury-Psychological Readiness to Return to Play (I-PRRS) questionnaire and their fear avoidance was measured by the Athlete Fear Avoidance Questionnaire (AFAQ). Results: Fifty injured athletes with a mean age of 23.3±4.0 years old responded to the I-PRRS and the AFAQ questionnaires. The average I-PRRS score was 46.5±9.1 AU. The evidence suggests that 60% of the athletes were not ready to return to sport (41.0±7.5 AU), whereas 40% were ready to return (54.8±3.1 AU). The difference in scores was not significant. The relationship between the AFAQ scores and the I-PRRS score for the 'ready' and 'not ready' groups was not significant (p=0.066). The mean AFAQ score (26.1±8.6 AU) for the 'not ready' group is marginally greater than the mean AFAQ score (21.6±7.5 AU) for the 'ready' group. There was a negative correlation between psychological readiness to return to sport and athletic fear avoidance (r =-0.508, p<0.001). Conclusion: There needs to be a greater utilisation of psychological assessment tools like the Injury-Psychological Readiness to Return to Play (I-PRRS) questionnaire, which can assist the athlete's support team, who can help identify athletes who are apprehensive about returning to sport after injury.

Clinical standards for diagnosis, treatment and prevention of post-COVID-19 lung disease.

BACKGROUND: The aim of these clinical standards is to provide guidance on 'best practice' care for the diagnosis, treatment and prevention of post-COVID-19 lung disease.METHODS: A panel of international experts representing scientific societies, associations and groups active in post-COVID-19 lung disease was identified; 45 completed a Delphi process. A 5-point Likert scale indicated level of agreement with the draft standards. The final version was approved by consensus (with 100% agreement).RESULTS: Four clinical standards were agreed for patients with a previous history of COVID-19: Standard 1, Patients with sequelae not explained by an alternative diagnosis should be evaluated for possible post-COVID-19 lung disease; Standard 2, Patients with lung function impairment, reduced exercise tolerance, reduced quality of life (QoL) or other relevant signs or ongoing symptoms ≥4 weeks after the onset of first symptoms should be evaluated for treatment and pulmonary rehabilitation (PR); Standard 3, The PR programme should be based on feasibility, effectiveness and cost-effectiveness criteria, organised according to local health services and tailored to an individual patient's needs; and Standard 4, Each patient undergoing and completing PR should be evaluated to determine its effectiveness and have access to a counselling/health education session.CONCLUSION: This is the first consensus-based set of clinical standards for the diagnosis, treatment and prevention of post-COVID-19 lung disease. Our aim is to improve patient care and QoL by guiding clinicians, programme managers and public health officers in planning and implementing a PR programme to manage post-COVID-19 lung disease.

Understanding the impact of the COVID­19 pandemic on healthcare services for adults during three waves of COVID­19 infections: A South African private sector experience.

BACKGROUND: Since the onset of the COVID­19 pandemic, healthcare resources have been repurposed to focus on COVID­19. Resource reallocation and restrictions to movement that affected general access to care may have inadvertently resulted in undue disruptions in the continuum of care for patients requiring non-COVID­19 healthcare services. OBJECTIVES: To describe the change in pattern of health service use in the South African (SA) private sector. METHODS: We conducted a retrospective study of a nationwide cohort of privately insured individuals. An analysis of claims data was performed for non-COVID­19 related healthcare services provided from April 2020 to December 2020 (year 1 of COVID­19) and April 2021 to December 2021 (year 2 of COVID­19) relative to the same period in 2019 prior to the COVID­19 pandemic in SA. Over and above plotting the monthly trends, we tested for statistical significance of the changes using a Wilcoxon test given the non-normality of all the outcomes. RESULTS: Between April and December 2020, relative to the same period in 2021, and also relative to the same period in 2019, we found a 31.9% (p<0.01) and a 16.6% (p<0.01) reduction in emergency room visits, respectively; a 35.9% (p<0.01) and 20.5% (p<0.01) reduction in medical hospital admissions; a 27.4% (p=0.01) and 13.0% (p=0.03) reduction in surgical hospital admissions; a 14.5% (p<0.01) and 4.1% (p=0.16) reduction in face-to-face general practitioner consultations for chronic members; a 24.9% (p=0.06) and 5.2% (p=0.54) reduction in mammography for female members; a 23.4% (p=0.03) and 10.8% (p=0.09) reduction in Pap smear screenings for female members; a 16.5% (p=0.08) and 12.1% (p=0.27) reduction in colorectal cancer registrations and an 18.2% (p=0.08) and 8.9% (p=0.07) decrease in all oncology diagnoses. Uptake of telehealth services throughout the healthcare delivery system increased by 5 708% in 2020 compared with 2019, and 36.1% for 2021 compared with 2020. CONCLUSION: A significant reduction in emergency room visits, hospital admissions and utilisation of primary care services was observed since the start of the pandemic. Further research is required to understand if there are long-term consequences of delayed care. An increase in the use of digital consultations was observed. Research on their acceptability and effectiveness may open new modalities of care, which may have cost- and time-saving benefits.

The supernumerary registrar experience in KwaZulu-Natal.

BACKGROUND: We sought to assess the experiences of trainees enrolled in the supernumerary registrar programme at the University of KwaZulu-Natal, South Africa, with a specific focus on their assimilation into host clinical units and their intentions to return to their home countries upon completion of the training. METHODS: This was a cross-sectional survey involving 50 supernumerary registrars attached to six academic hospitals affiliated with the University of KwaZulu-Natal. The survey collected information on registrar's demographics and financial support, speciality, opportunities for advanced training in their home country, assimilation into host clinical units and intentions to return home upon completing the training. The survey data were analysed using descriptive statistics. RESULTS: The majority of supernumeraries were < 36 years old (n = 32, 64%), male (n = 31, 62%), and self-funded (n = 31, 62%). Only a few supernumeraries were associated with a training facility in their home country (n = 9, 18%). Most supernumeraries (n = 44, 88%) reported not having an equivalent training programme in their home country. Awareness of the programme was predominantly acquired through self-research (n = 35, 70%), and the application process was perceived as problematic by many supernumeraries (n = 46, 92%). Most supernumeraries (n = 43, 86%) assimilated into their host clinical units, and nearly one-third (n = 16, 32%) did not plan on returning home upon completion of their training. CONCLUSION: Most supernumerary registrars assimilate into host clinical units and play an important role in service delivery during their training. Mechanisms should be put in place to facilitate retention of these individuals in their home countries upon completion of their training.

Current intraoperative storage and handling practices of autologous bypass conduit: A survey of the royal australasian college of surgeons.

During bypass surgery for peripheral arterial occlusive disease and ischaemic heart disease, autologous graft conduit including great saphenous veins and radial arteries are frequently stored in solution. Endothelial damage adversely affects the performance and patency of autologous bypass grafts, and intraoperative graft storage solutions have been shown to influence this process. The distribution of storage solutions currently used amongst Cardiothoracic and Vascular Surgeons from Australia and New Zealand is not well defined in the literature. The aim of this study was to determine current practices regarding autologous graft storage and handling amongst this cohort of surgeons, and discuss their potential relevance in the context of early graft failure. From this survey, the most frequently used storage solutions were heparinized saline for great saphenous veins, and pH-buffered solutions for radial arteries. Duration of storage was 30-45 min for almost half of respondents, although responses to this question were limited. Further research is required to investigate whether ischaemic endothelial injury generates a prothrombotic state, whether different storage media can alter this state, and whether this is directly associated with clinical outcomes of interest such as early graft failure.

Effect of short-term exposure to ambient nitrogen dioxide and particulate matter on repeated lung function measures in infancy: A South African birth cohort.

BACKGROUND: The developing lung is highly susceptible to environmental toxicants, with both short- and long-term exposure to ambient air pollutants linked to early childhood effects. This study assessed the short-term exposure effects of nitrogen dioxide (NO2) and particulate matter (PM10) on lung function in infants aged 6 weeks, 6, 12 and 24 months, the early developmental phase of child growth. METHODS: Lung function was determined by multiple breath washout and tidal breathing measurement in non-sedated infants. Individual exposure to NO2 and PM10 was determined by hybrid land use regression and dispersion modelling, with two-week average estimates (preceding the test date). Linear mixed models were used to adjust for the repeated measures design and an age*exposure interaction was introduced to obtain effect estimates for each age group. RESULTS: There were 165 infants that had lung function testing, with 82 of them having more than one test occasion. Exposure to PM10 (µg/m3) resulted in a decline in tidal volume at 6 weeks [-0.4 ml (-0.9; 0.0), p = 0.065], 6 months [-0.5 ml (-1.0; 0.0), p = 0.046] and 12 months [-0.3 ml (-0.7; 0.0), p = 0.045]. PM10 was related to an increase in respiratory rate and minute ventilation, while a decline was observed for functional residual capacity for the same age groups, though not statistically significant for these outcomes. Such associations were however less evident for exposure to NO2, with inconsistent changes observed across measurement parameters and age groups. CONCLUSION: Our study suggests that PM10 results in acute lung function impairments among infants from a low-socioeconomic setting, while the association with NO2 is less convincing.

Functional connectivity of the world's protected areas.

Global policies call for connecting protected areas (PAs) to conserve the flow of animals and genes across changing landscapes, yet whether global PA networks currently support animal movement-and where connectivity conservation is most critical-remain largely unknown. In this study, we map the functional connectivity of the world's terrestrial PAs and quantify national PA connectivity through the lens of moving mammals. We find that mitigating the human footprint may improve connectivity more than adding new PAs, although both strategies together maximize benefits. The most globally important areas of concentrated mammal movement remain unprotected, with 71% of these overlapping with global biodiversity priority areas and 6% occurring on land with moderate to high human modification. Conservation and restoration of critical connectivity areas could safeguard PA connectivity while supporting other global conservation priorities.

Dietary supplements and beverages: Knowledge, attitudes, and practices among semi-professional soccer players in KwaZulu-Natal, South Africa.

Background: The ingestion of dietary supplements and beverages is prevalent in soccer, at the amateur and professional level. The absence of professional advice at non-professional level makes amateur soccer players susceptible to ingesting unsafe supplements. Objectives: To determine the knowledge, attitudes and practices of ABC Motsepe League (semi-professional) players in KwaZulu-Natal regarding the use of dietary supplements and beverages. Methods: Three hundred and forty-three soccer players participated in a cross-sectional study. Knowledge, attitudes and practices were determined using a questionnaire. Researchers visited twelve teams. On the day of the visit to each team, information sheets and questionnaires were given to participants. Questionnaires were collected immediately following completion. Descriptive statistics were used, including means and standard deviations, where applicable. Inferential statistics, Chi-square and binomial tests were used to analyse the results. Statistical significance was set at p < 0.05. Results: Sports beverages were the most recommended and commonly used, followed by energy beverages. Dietary supplements were the least-known used. Participants used beverages and dietary supplements to assist in providing more energy (67%), improve health (65%) and improve performance (55%) (p<0.001). Seventy-three percent of participants lacked knowledge about the anti-doping policy (p<0.001), with 87% having never attended a workshop on the safe use of supplements and beverages, or anti-doping awareness campaigns (p<0.001). Thirty-eight percent had not heard of the South African Institute for Drug-Free Sport (SAIDS), and 84% were not familiar with the yearly updated World Anti-Doping Agency's (WADA) prohibited list (p<0.001). Of the 59% who did not take dietary supplements or beverages, 75% had insufficient information regarding them (p<0.001), 66% indicated that dietary supplements and beverages were costly (p=0.001), and 55% indicated they did not need dietary supplements and beverages (p=0.32). Conclusion: There is a need for an educational programme on the safe use of dietary supplements, and sports and energy beverages among KwaZulu-Natal semi-professional soccer players.

Comparative outcome analysis of trauma and non-trauma emergency laparotomy using a modified NELA tool format.

BACKGROUND: Emergency laparotomy (EL) encompasses a diverse range of procedures that general surgeons commonly perform for both trauma and non-trauma related conditions in South Africa (SA). Despite differences in the underlying pathology and influence of the surgical procedure, these patients share one care pathway for preoperative, operative and postoperative care. This study reviewed patients undergoing trauma EL and non-trauma EL in a general surgery setting at a rural KwaZulu-Natal tertiary hospital to compare results between the groups using a modified National Emergency Laparotomy Audit (NELA) tool format. METHODS: Consecutive adult patients undergoing midline EL at Ngwelezana Hospital between 1 March and 31 May 2018 were included. Patient factors analysed were demographic data (age, gender) and risk factors: National Confidential Enquiry into Perioperative Deaths (NCEPOD) grade, American Society of Anesthesiologists (ASA) grade, and comorbidity. Process of care factors included grade of the physician, time to surgery, time of surgery and duration of surgery. The primary outcome measure was mortality. Secondary outcome measures were intensive care unit (ICU) admissions, complications, and length of stay (LOS) > 14 days. RESULTS: The study included 110 participants who met the inclusion criteria representing a total of 174 laparotomies. The trauma EL group had lower ASA grades (p = 0.003), less comorbidities (p = 0.002), more often went to theatre within six hours (42/56; 75.0%) (p < 0.001), more admissions to ICU (23/56; 41.1%) (p < 0.001), more complications (29/56; 51.8%) (p = 0.039), and higher length of stay > 14 days (16/56; 28.6%) (p = 0.037). CONCLUSION: The trauma EL group represents a high-risk group for morbidity and mortality at Ngwelezana Hospital.

The Isokinetic Rugby Union Physical Work Evaluation (RUPWE) protocol: Can Rugby Union Players meet the physical work demands of the game?

Background: To protect the lumbar spine from excessive forces, rugby union players need to demonstrate the work ability of the trunk extensors and flexors to meet the physical demands. Aim: To measure and evaluate whether rugby union players were able to meet the imposed physical work demand, considering limitations, tolerances and resistance to fatigue, using isokinetic dynamometry for trunk extensors (TE) and trunk flexors (TF). Methods: Fifty-five male players, between the ages of 18 and 23 years, participated in the study. All participants completed a PAR-Q (pre-activity risk) questionnaire before the isokinetic testing. Their height was between 1.80 ± 0.67 m and body mass was 86.0 ± 17.5 kg. Participants were subjected to a newly designed protocol using the Biodex Isokinetic System 3 Dynamometer, called the Rugby Union Physical Work Evaluation (RUPWE). Results: There was a significant difference between the forwards' trunk extensor peak torque to body weight 488% ± 119% and the trunk flexor peak torque to body weight 289% ± 73%. Furthermore, there was a large effect size between trunk extensor and trunk flexor muscle performance for the forwards (d =2.0) and backs (d =1.9) for peak torque to body weight. Spearman's rank-order correlations (rs) showed a moderate negative correlation for the forwards between trunk extensor peak torque to body weight and time to peak torque, (rs = -0.4; p=0.018). There is a strong negative correlation for the backs between trunk extensor peak torque to body weight and time to peak torque, (rs = -0.6; p=0.003). Conclusion: The physical work evaluation protocol can be used as a screening tool for rugby players as it measures the extensive mechanical load placed on the lumbar region. This has the potential to evaluate their athletic performance for the demands of tackling and scrumming.

Evolution of mutualistic behaviour between Chlorella sorokiniana and Saccharomyces cerevisiae within a synthetic environment.

Yeast and microalgae are microorganisms with widely diverging physiological and biotechnological properties. Accordingly, their fields of applications diverge: yeasts are primarily applied in processes related to fermentation, while microalgae are used for the production of high-value metabolites and green technologies such as carbon capture. Heterotrophic-autotrophic systems and synthetic ecology approaches have been proposed as tools to achieve stable combinations of such evolutionarily unrelated species. We describe an entirely novel synthetic ecology-based approach to evolve co-operative behaviour between winery wastewater isolates of the yeast Saccharomyces cerevisiae and microalga Chlorella sorokiniana. The data show that biomass production and mutualistic growth improved when co-evolved yeast and microalgae strains were paired together. Combinations of co-evolved strains displayed a range of phenotypes, including differences in amino acid profiles. Taken together, the results demonstrate that biotic selection pressures can lead to improved mutualistic growth phenotypes over relatively short time periods.

Measuring quality outcomes across hospital systems: Using a claims data model for risk adjustment of mortality rates.

Healthcare delivery systems around the world are designing care through value-based models where value is defined as a function of quality of care outcomes and cost. Mortality is a sentinel outcome measure of quality of care, of fundamental importance to patients and providers. Discovery Health (DH), an administrative funder of healthcare in South Africa (SA), uses service claims data of client medical schemes to examine standardised mortality rates (SMRs) at condition level across hospital systems for the purpose of healthcare system improvement. To accurately examine and contrast variation in condition-level SMRs across acute hospital systems, this outcome metric needs to be risk-adjusted for patient characteristics that make mortality more, or less, likely to occur. This article describes and evaluates the validity of risk-adjustment methods applied to service claims data to accurately determine SMRs across hospital systems. While service claims data may have limitations regarding case risk adjustment, it is important that we do not lose the important opportunity to use claims data as a reliable proxy to comment on the quality of care within healthcare systems. This methodology is robust in its demonstration of variation of performance on mortality outcomes across hospital systems. For the measurement period January 2014 - December 2016, the average risk-adjusted SMRs across hospital systems where DH members were hospitalised for acute myocardial infarction, stroke, pneumonia and coronary artery bypass graft procedures were 9.7%, 8.0%, 5.3% and 3.2%, respectively. This exercise of transparently examining variation in SMRs at hospital system level is the first of its kind in SA's private sector. Our methodological exercise is used to establish a local pattern of variation of SMRs in the private sector as the base off which to scrutinise reasons for variation and off which to build quality of care improvement strategies. High-performing healthcare systems must seek out opportunities for learning and continuous improvement such as those offered by examining important quality of care outcome measures across hospitals.

Evaluating the impacts of protected areas on human well-being across the developing world.

Protected areas (PAs) are fundamental for biodiversity conservation, yet their impacts on nearby residents are contested. We synthesized environmental and socioeconomic conditions of >87,000 children in >60,000 households situated either near or far from >600 PAs within 34 developing countries. We used quasi-experimental hierarchical regression to isolate the impact of living near a PA on several aspects of human well-being. Households near PAs with tourism also had higher wealth levels (by 17%) and a lower likelihood of poverty (by 16%) than similar households living far from PAs. Children under 5 years old living near multiple-use PAs with tourism also had higher height-for-age scores (by 10%) and were less likely to be stunted (by 13%) than similar children living far from PAs. For the largest and most comprehensive socioeconomic-environmental dataset yet assembled, we found no evidence of negative PA impacts and consistent statistical evidence to suggest PAs can positively affect human well-being.

Ketone body supplement label claims: what supplement has been supplemented?

Background: There is a keen interest in performance-enhancing supplementation and the associated benefits, despite reports of incorrect label claims made by manufacturers and the questionable efficacy of the supplements. The use of ketone body supplements as a source of fuel during exercise and sporting performance, in particular, is of interest to sportspeople. By increasing blood ketone body levels, with an accompanying decrease in blood glucose, may indicate a state of nutritional ketosis, whereby the body no longer relies on glucose metabolism but rather the metabolism of ketone bodies. This could be beneficial for long, slow steady-state endurance exercise. Discussion: There are numerous ketone body supplements on the market manufactured in South Africa and internationally. However, unlike medicines, the sports supplementation industry is poorly regulated. Furthermore, ketone body supplementation with regard to its effects on improving exercise and athletic performance is still unconvincing. Conclusion: Within the ever-changing sports supplementation industry, ketone body supplements are being used despite controversies regarding the accuracy and scientific merit of label claims. The ingredients and their quantities, as well as the performance benefits, need to be objectively validated.

Maternal miRNA-146a G/C rs2910164 variation, HIV/AIDS and nitrogen oxide pollution exposure collectively affects foetal growth.

OBJECTIVE:: Nitrogen oxide (NOx) pollution and human immunodeficiency virus (HIV)/AIDS intensify inflammation during pregnancy and linked with adverse birth outcomes (ABOs). MicroRNA (miRNA)-146a plays a crucial role in regulating inflammation in the NF-κB pathway. The G/C rs2910164 dampens miRNA-146a activity and linked with inflammatory diseases. The present study investigated whether HIV/AIDS and NOx exposure throughout pregnancy further intensifies ABO in Black South African women genotyped for the rs2910164. METHODS:: Pregnant women ( n = 300) were subdivided into low, medium and high NOx exposure groups, genotyped for the miRNA-146a G/C rs2910164 using polymerase chain reaction-restriction fragment length polymorphism, and further stratified based on HIV status. RESULTS:: Unstratified data (HIV+ and HIV- mothers combined): Mothers from the high NOx group with the variant C-allele had low blood iron levels ( p = 0.0238), and had babies with reduced birthweights ( p = 0.0283). As NOx increased, the prevalence of preterm birth and low birth weight also increased in mothers with the variant C-allele versus wildtype G-allele. HIV-infected mothers: In all NOx exposure groups, mothers with the variant C-allele had higher systolic blood pressure (low: p = 0.0386, medium: p = 0.0367 and high: p = 0.0109) and had babies with lower Appearance, Pulse, Grimace, Activity and Respiration scores at 1 min (low: p = 0.0190, medium: p = 0.0301 and high: p = 0.0361). CONCLUSION:: Maternal rs2910164 variant C-allele, NOx pollution and HIV/AIDS might collectively play a role in intensifying gestational hypertension and ABO.

Regulating the South African sport supplement industry: 'Whey' overdue.

The South African sport supplement industry has experienced rapid growth in recent years. Despite the massive market demand, this industry remains poorly regulated. From raw ingredient contamination to label compliance discrepancies, the sport supplement industry is an area of growing concern and warrants further public debate.

IL-17A[G197G]-Association between NOx and gestational age in a South African birth cohort.

Interleukin (IL-)17A, plays a role in pathogenic defence, but is implicated in chronic inflammatory diseases, and has recently been associated with variable pregnancy outcomes. We investigated the role of maternal IL-17-[G197A]-specific effects of third-trimester IL-17 mRNA expression, NOx exposure levels and other variables on gestational age, in the Mother and Child in the Environment (MACE) birth cohort in South Africa. A total of 327 participants were genotyped for IL-17-[G197A] by polymerase chain reaction restriction-fragment length polymorphism (PCR-RFLP). Quantitative real-time PCR was used to quantitate IL-17-mRNA expression in whole blood. Multivariate linear regression analysis, stratified by IL-17-[G197A] genotype, was used to test for effects of NOx , IL17A/GAPDH, haemoglobin, body mass index, HIV-1 positivity, maternal education and income level on gestational age. Lower expression was associated with the IL-17-GG versus GA in the cohort and HIV-1-negative group (p = .0007, p = .0058), while no difference was observed in the HIV-1 positives. Elevated IL-17A expression was observed in the high NOx exposure groups, within IL-17[G197G] (p = .0004). IL-17[G197G] was associated with PTB (p < .0001), and the PTB group had lower IL-17A expression compared to the full-term group (p = .0002). IL-17 expression was associated with an increase in gestational age (p = .038), and NOx was associated with a decrease in gestational age in the IL-17[G197G] model (p = .046).

Developing a predictive model for fine particulate matter concentrations in low socio-economic households in Durban, South Africa.

In low-resource settings, there is a need to develop models that can address contributions of household and outdoor sources to population exposures. The aim of the study was to model indoor PM2.5 using household characteristics, activities, and outdoor sources. Households belonging to participants in the Mother and Child in the Environment (MACE) birth cohort, in Durban, South Africa, were randomly selected. A structured walk-through identified variables likely to generate PM2.5 . MiniVol samplers were used to monitor PM2.5 for a period of 24 hours, followed by a post-activity questionnaire. Factor analysis was used as a variable reduction tool. Levels of PM2.5 in the south were higher than in the north of the city (P < .05); crowding and dwelling type, household emissions (incense, candles, cooking), and household smoking practices were factors associated with an increase in PM2.5 levels (P < .05), while room magnitude and natural ventilation factors were associated with a decrease in the PM2.5 levels (P < .05). A reasonably robust PM2.5 predictive model was obtained with model R2 of 50%. Recognizing the challenges in characterizing exposure in environmental epidemiological studies, particularly in resource-constrained settings, modeling provides an opportunity to reasonably estimate indoor pollutant levels in unmeasured homes.