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Antenatal corticosteroids are given to pregnant people at risk of preterm birth to reduce newborn morbidity, including respiratory distress syndrome. However, there has been concern surrounding potential adverse effects on subsequent generations. Animal studies have demonstrated endocrine and metabolic changes in those exposed to corticosteroids in utero (F1) and in the second generation (F2). We aimed to assess the effects of parental antenatal corticosteroid exposure on health of the second generation (F2) of Auckland Steroid Trial (AST) participants. In the AST, women (F0) expected to birth between 24 and 36 weeks’ gestation were randomised to betamethasone or placebo. When their children (F1) were 50 years old, they and their children (F2) were followed up with a self-report questionnaire and data linkage. The primary outcome for this analysis was body mass index (BMI) z-score in the F2 generation. Secondary outcomes included respiratory, cardiovascular, neurodevelopmental, mental and general health, and social outcomes. Of the 213 F2 participants, 144 had BMI data available. There was no difference in BMI z-score between participants whose parent was exposed to betamethasone versus placebo (mean (SD) 0.63 (1.45), N = 77 vs 0.41 (1.28), N = 67, adjusted mean difference (95% confidence interval) = 0.16 (-0.37, 0.69)). There was no evidence of a difference in rates of overweight, diabetes, respiratory disease, cardiometabolic risk factors, neurodevelopmental difficulties, mental health difficulties and social outcomes between parental betamethasone versus placebo exposure groups, but confidence intervals were wide. These findings are reassuring regarding the intergenerational safety of antenatal corticosteroids.
Excess sodium consumption, mostly from dietary salt, causes high blood pressure and an increased risk of cardiovascular disease(1). In parallel, insufficient potassium intake also contributes to raised blood pressure(2). Switching regular salt for potassium-enriched salt, where a proportion of the sodium chloride is replaced with potassium chloride, is a promising public health intervention to address both these issues(3). However, the supply chain to support increased use of potassium-enriched salt in Australia is not well understood. The objectives of this study were to investigate how the salt supply chain operates in Australia and to obtain food industry stakeholder perspectives on the technical barriers and enablers to increased potassium-enriched salt use. Twelve interviews with industry stakeholders (from food companies, salt manufacturers and trade associations) were conducted and thematically analysed using a template analysis method. Two top-level themes were developed: ‘supply chain practices’ and ‘technical barriers and enablers’. The potassium-enriched salt supply chain was described as less well-established than the low-cost production and distribution of regular salt in Australia. However, food companies reported not having difficulty sourcing potassium chloride. For Australian food industry stakeholders, cost, flavour and functionality were perceived as key barriers to increased uptake of potassium-enriched salt as a food ingredient. Stakeholders from food companies were hesitant to use potassium-enriched salt due to concerns about bitter or metallic flavours and uncertainty whether it would provide the same microbial/shelf-life functions or textural quality as regular salt. However, potassium-enriched salt manufacturers had divergent opinions stating potassium-enriched salt was a suitable functional replacement for regular salt and that flavour differences observed may be due to the incorrect use of potassium chloride as opposed to use of a purpose-made potassium-enriched salt. Stakeholders identified that establishing a stable and affordable supply of potassium-enriched salt in Australia and increased support for food technology research and development would enable increased use. To improve uptake of potassium-enriched salt by the Australian food industry, future efforts should focus on strengthening potassium-enriched salt supply chains and improving appeal for food industry to use in manufacturing and for consumers to purchase. Public health advocacy efforts should ensure that industry is equipped with the latest evidence on the feasibility and benefits of using potassium-enriched salt as an ingredient. Ongoing engagement is critical to ensure that industry is aware of their responsibility and opportunity to offer healthier foods to consumers by switching regular salt to potassium-enriched salt within foods.
Most Australians consume excess sodium and inadequate potassium both causing high blood pressure—the leading risk factor for death in Australia(1). Switching regular salt to potassium-enriched, reduced-sodium salt is a novel solution, shown to lower blood pressure, cardiovascular disease risk and premature death(2). The aim of this study was to explore Australian adults’ knowledge, attitudes and behaviours related to potassium-enriched salt. Adults aged ≥ 18 years and who were the main or joint grocery buyer were recruited through a web panel provider between February and March 2024 to complete an online survey. Quotas were used to achieve representation of the age, sex and geographical distribution in Australia. The survey was developed based on existing questionnaires of consumers’ perception of potassium-enriched salt identified in a systematic review, and the behaviour change wheel framework to allow for a systematic assessment of consumers’ capability, opportunity and motivation to switch to potassium-enriched salt. Survey responses that were completed in less than one-third of the median time (< two minutes and 20 seconds) were excluded from analysis. All data were collated and analysed using the statistical program Stata/SE 14.0 (StataCorp LP). A total of 4113 adults (52% female) with a mean (SD) age of 47.9 years (18.3) completed the survey and were eligible for inclusion. About half (47%) of participants reported that they have seen/heard of a potassium-enriched salt. Of those, 41% always, often or sometimes use potassium enriched salt with the main reasons being it is what’s available at home (32%) and it was recommended by a healthcare professional (29%). However, only 3% of all participants reported that potassium-enriched salt or low-sodium salt was the main type of salt used during cooking and eating at home. Most participants reported that they could be influenced to switch to potassium-enriched salt by the following factors, if it was better for their health (85%), affordable (78%), recommended by healthcare professionals (75%) and tasted good (73%). Most participants believed that individuals (77%), food manufacturers (68%) and fast-food chains (65%) were responsible for making the switch to potassium-enriched when told it was a healthier alternative to regular salt. A greater proportion of participants correctly identified that eating more potassium was beneficial for health (73%) compared to those that correctly identified that eating more sodium was not beneficial for health (57%). While current knowledge and use of potassium-enriched salt is low in Australia, the study identified existing and potential drivers for switching to potassium-enriched salt. The study highlights greater awareness-raising activities about the health benefits and acceptable taste of potassium-enriched salt, particularly by healthcare professionals, could help scale-up the switch to potassium-enriched salt.
Polymorphisms in the vitamin D receptor (VDR) gene (BsmI (rs1544410), FokI (rs2228570), ApaI (rs7975232), TaqI (rs731236)) and low vitamin D concentrations have previously been associated with type 1 diabetes (T1D). Vitamin D is thought to mediate the switch from a pro-inflammatory Th1 response to an anti-inflammatory Th2 response which is protective against the development of T1D. These associations are inconsistent across studies and population groups. These associations have not been investigated in the South African black population. Thus, this observational, case-control study aims to address this knowledge gap. South African black participants with T1D (cases; n = 182) and healthy controls (n = 151) were genotyped for the four VDR polymorphisms using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Vitamin D levels were measured using high performance liquid chromatography (HPLC). Vitamin D levels were not significantly different between cases and controls (62.8 ± 20.7 vs. 59.5 ± 17.0 nmol/l, respectively; P = 0.122). Higher vitamin D levels were associated with the TaqI TT (P = 0.045) and FokI TT/TC (P = 0.014) genotypes in multivariate analyses. Furthermore, the TaqI TT genotype was associated with T1D status in multivariate analysis (P = 0.040). The FokI CC genotype increases the transcription of CYP24A1, resulting in vitamin D catabolism and thus decreased vitamin D concentration through the action of 24-hydroxlase. The TaqI TT genotype results in increased vitamin D potentially through calcium metabolism feedback pathways. In addition, the TaqI TT genotype is associated with T1D through a vitamin D-independent mechanism and may be in linkage disequilibrium with a true causative variant.
A demonstration of a fully onboard method for generating background oriented schlieren (BOS) data on a jet exhaust is presented. Readily available commercial camera equipment is used to capture in-flight imagery of a miniature jet engine exhaust mounted on a custom-built model aircraft. The setup for image acquisition and processing algorithms are described. A new process for registration of images to reduce the degrading effects of vibration and flexure of the airframe are developed and presented along with the underpinning BOS algorithm. Results show that jet flows can be visualised using this technique using a contained system on a single aircraft and demonstrate how a simple technique, such as BOS, can be democratised to such an extent that the cost of conducting in-flight jet measurements can be reduced to the budget of any model aircraft flyer.
To determine the long-term, spontaneous growth arrest rates in a large cohort of vestibular schwannoma patients.
Methods
This paper describes a retrospective case series of 735 vestibular schwannoma patients organised into four groups: group A patients showed tumour growth which then stopped without any treatment; group B patients showed tumour growth which continued, but were managed conservatively; group C patients had a growing vestibular schwannoma and received active treatment; and group D patients had a stable, non-growing vestibular schwannoma. Demographics, tumour size and vestibular schwannoma growth rate (mm/month) were recorded.
Results
A total of 288 patients (39.2 per cent) had growing vestibular schwannomas. Of the patients, 103 (35.8 per cent) were managed conservatively, with 52 patients (50.5 per cent of the conservative management group, 18 per cent of the total growing vestibular schwannoma group) showing growth arrest, which occurred on average at four years following the diagnosis. Eighty-two per cent of vestibular schwannomas stopped growing within five years. Only differences between age (p = 0.016) and vestibular schwannoma size (p = 0.0008) were significant.
Conclusion
Approximately 20 per cent of growing vestibular schwannomas spontaneously stop growing, predominantly within the first five years; this is important for long-term management.
To determine the impact of pre-operative intratympanic gentamicin injection on the recovery of patients undergoing translabyrinthine resection of vestibular schwannomas.
Methods
This prospective, case–control pilot study included eight patients undergoing surgical labyrinthectomy, divided into two groups: four patients who received pre-operative intratympanic gentamicin and four patients who did not. The post-operative six-canal video head impulse test responses and length of in-patient stay were assessed.
Results
The average length of stay was shorter for patients who received intratympanic gentamicin (6.75 days; range, 6–7 days) than for those who did not (9.5 days; range, 8–11 days) (p = 0.0073). Additionally, the gentamicin group had normal post-operative video head impulse test responses in the contralateral ear, while the non-gentamicin group did not.
Conclusion
Pre-operative intratympanic gentamicin improves the recovery following vestibular schwannoma resection, eliminating, as per the video head impulse test, the impact of labyrinthectomy on the contralateral labyrinth.
To examine when cochlear fibrosis occurs following a translabyrinthine approach for vestibular schwannoma resection, and to determine the safest time window for potential cochlear implantation in cases with a preserved cochlear nerve.
Methods
This study retrospectively reviewed the post-operative magnetic resonance imaging scans of patients undergoing a translabyrinthine approach for vestibular schwannoma resection, assessing the fluid signal within the cochlea. Cochleae were graded based on the Isaacson et al. system (from grade 0 – no obstruction, to grade 4 – complete obliteration).
Results
Thirty-nine patients fulfilled the inclusion criteria. The cochleae showed no evidence of obliteration in: 75 per cent of patients at six months, 38.5 per cent at one year and 27 per cent beyond one year. Most changes happened between 6 and 12 months after vestibular schwannoma resection, with cases of an unobstructed cochlear decreasing dramatically, from 75 per cent to 38.5 per cent, within this time.
Conclusion
The progress of cochlear obliteration that occurred between 6 and 12 months following vestibular schwannoma resection indicates that the first 6 months provides a safer time window for cochlear patency.
Recovery Colleges are opening internationally. The evaluation focus has been on outcomes for Recovery College students who use mental health services. However, benefits may also arise for: staff who attend or co-deliver courses; the mental health and social care service hosting the Recovery College; and wider society. A theory-based change model characterising how Recovery Colleges impact at these higher levels is needed for formal evaluation of their impact, and to inform future Recovery College development. The aim of this study was to develop a stratified theory identifying candidate mechanisms of action and outcomes (impact) for Recovery Colleges at staff, services and societal levels.
Methods
Inductive thematic analysis of 44 publications identified in a systematised review was supplemented by collaborative analysis involving a lived experience advisory panel to develop a preliminary theoretical framework. This was refined through semi-structured interviews with 33 Recovery College stakeholders (service user students, peer/non-peer trainers, managers, community partners, clinicians) in three sites in England.
Results
Candidate mechanisms of action and outcomes were identified at staff, services and societal levels. At the staff level, experiencing new relationships may change attitudes and associated professional practice. Identified outcomes for staff included: experiencing and valuing co-production; changed perceptions of service users; and increased passion and job motivation. At the services level, Recovery Colleges often develop somewhat separately from their host system, reducing the reach of the college into the host organisation but allowing development of an alternative culture giving experiential learning opportunities to staff around co-production and the role of a peer workforce. At the societal level, partnering with community-based agencies gave other members of the public opportunities for learning alongside people with mental health problems and enabled community agencies to work with people they might not have otherwise. Recovery Colleges also gave opportunities to beneficially impact on community attitudes.
Conclusions
This study is the first to characterise the mechanisms of action and impact of Recovery Colleges on mental health staff, mental health and social care services, and wider society. The findings suggest that a certain distance is needed in the relationship between the Recovery College and its host organisation if a genuine cultural alternative is to be created. Different strategies are needed depending on what level of impact is intended, and this study can inform decision-making about mechanisms to prioritise. Future research into Recovery Colleges should include contextual evaluation of these higher level impacts, and investigate effectiveness and harms.
Anti-retroviral therapy (ART) regimes for HIV are associated with raised levels of circulating triglycerides (TGs) in western populations. However, there are limited data on the impact of ART on cardiometabolic risk in sub-Saharan African (SSA) populations.
Methods
Pooled analyses of 14 studies comprising 21 023 individuals, on whom relevant cardiometabolic risk factors (including TG), HIV and ART status were assessed between 2003 and 2014, in SSA. The association between ART and raised TG (>2.3 mmol/L) was analysed using regression models.
Findings
Among 10 615 individuals, ART was associated with a two-fold higher probability of raised TG (RR 2.05, 95% CI 1.51–2.77, I2 = 45.2%). The associations between ART and raised blood pressure, glucose, HbA1c, and other lipids were inconsistent across studies.
Interpretation
Evidence from this study confirms the association of ART with raised TG in SSA populations. Given the possible causal effect of raised TG on cardiovascular disease (CVD), the evidence highlights the need for prospective studies to clarify the impact of long term ART on CVD outcomes in SSA.
Africa is experiencing a rapid increase in adult obesity and associated cardiometabolic diseases (CMDs). The H3Africa AWI-Gen Collaborative Centre was established to examine genomic and environmental factors that influence body composition, body fat distribution and CMD risk, with the aim to provide insights towards effective treatment and intervention strategies. It provides a research platform of over 10 500 participants, 40–60 years old, from Burkina Faso, Ghana, Kenya and South Africa. Following a process that involved community engagement, training of project staff and participant informed consent, participants were administered detailed questionnaires, anthropometric measurements were taken and biospecimens collected. This generated a wealth of demographic, health history, environmental, behavioural and biomarker data. The H3Africa SNP array will be used for genome-wide association studies. AWI-Gen is building capacity to perform large epidemiological, genomic and epigenomic studies across several African counties and strives to become a valuable resource for research collaborations in Africa.
The blue compact dwarf galaxy NGC 5253 hosts a very young starburst containing twin nuclear star clusters. Calzetti et al. (2015) find that the two clusters have an age of 1 Myr, in contradiction to the age of 3–5 Myr inferred from the presence of Wolf-Rayet (W-R) spectral features. We use Hubble Space Telescope (HST) far-ultraviolet (FUV) and ground-based optical spectra to show that the cluster stellar features arise from very massive stars (VMS), with masses greater than 100 M⊙, at an age of 1–2 Myr. We discuss the implications of this and show that the very high ionizing flux can only be explained by VMS. We further discuss our findings in the context of VMS contributing to He ii λ1640 emission in high redshift galaxies, and emphasize that population synthesis models with upper mass cut-offs greater than 100 M⊙ are crucial for future studies of young massive clusters.
We present VLT/MUSE observations of NGC 2070, the dominant ionizing nebula of 30 Doradus in the LMC, plus HST/STIS spectroscopy of its central star cluster R136. Integral Field Spectroscopy (MUSE) and pseudo IFS (STIS) together provides a complete census of all massive stars within the central 30×30 parsec2 of the Tarantula. We discuss the integrated far-UV spectrum of R136, of particular interest for UV studies of young extragalactic star clusters. Strong He iiλ1640 emission at very early ages (1–2 Myr) from very massive stars cannot be reproduced by current population synthesis models, even those incorporating binary evolution and very massive stars. A nebular analysis of the integrated MUSE dataset implies an age of ~4.5 Myr for NGC 2070. Wolf-Rayet features provide alternative age diagnostics, with the primary contribution to the integrated Wolf-Rayet bumps arising from R140 rather than the more numerous H-rich WN stars in R136. Caution should be used when interpreting spatially extended observations of extragalactic star-forming regions.
Today there is growing interest on the part of aeronautical engineers in forgings of large size, for three main reasons. Certain types of forgings will naturally need to be bigger as the aircraft itself becomes bigger; more composite structures are being replaced by single components made as forgings; and there is an increasing use of complex units machined directly from blocks of metal which are too big in at least one dimension to be made as extrusions or rolled plate. It is with these larger forgings that we are mainly concerned. Their production presents many serious problems. It is reasonable to hope that some of these will be overcome as experience grows and techniques are improved but others seem to be inherent in the materials used and must be appreciated at the design stage of the component if fully satisfactory service is to be obtained.
A flush air data system uses surface pressure measurements to obtain speed and aerodynamic orientation of a flight vehicle. This paper investigates the use of a neural network to calibrate the air data system on a low-observable aircraft forebody with 22 pressure tappings. Wind tunnel data were obtained for between 0 and 25° angle of attack, 0 to 10° sideslip for speeds of 32, 37 and 45ms-1. Experimental data were used to train multilayer perceptron neural networks. A calibration accuracy of 0·322ms-1, 0·811° and 0·552° for speed, alpha and beta respectively was achieved just using the first five tappings on the nose cone. Increasing the number of tappings used as inputs to the neural network reduces the calibration error. A neural network with 22 inputs gives a best accuracy of 0·095ms-1, 0·15° and 0·085° for speed, α and β respectively. Trained networks show poor robustness to single sensor failures. Robustness is improved by preprocessing input data with an autoassociative network or by introducing sensor redundancy.
Fluidic flight controls enable forces and moments for flight vehicle trim and manoeuvre to be produced without use of conventional moving surface controls. This paper introduces a methodology for the design of Circulation Control (CC) and Fluidic Thrust Vectoring (FTV) as fluidic controls for roll and pitch. Work was undertaken as part of the multidisciplinary FLAVIIR project, with the goal of providing full authority fluidic flight controls sufficient for a fully flapless flight of an 80kg class demonstrator aircraft known as DEMON. The design methodology considers drag, mass, volume and pneumatic power requirements as part of the overall design cost function. It is shown that the fundamental flow physics of both CC and FTV are similar, and hence there are strong similarities to the design approach of each. Flight ready CC and FTV hardware has been designed, manufactured and ground tested. The CC system was successfully wind tunnel demonstrated on an 85% scale half model of the DEMON. The design condition of a control ΔCL of 0·1 was achieved with a blowing coefficient of 0·01, giving a useable control gain of 10. The FTV system was static tested using a micro gas turbine source. The control characteristic was ‘N’ shaped, consisting of an initial high gain response in a negative sense (gain = −30) followed by a low gain response in a positive sense (gain = +3) at higher blowing rate. CC and FTV control hardware directly contributes to around 6% to the overall mass of the flight vehicle, however provision of pneumatic power carries a significant mass penalty unless generated as part of an integrated engine bleed system.
The use of flow control (FC) technology on civil transport aircraft is seen as a potential means of providing a step change in aerodynamic performance in the 2020 time frame. There has been extensive research into the flow physics associated with FC. This paper focuses on developing an understanding of the costs and design drivers associated with the systems needed and certification. The research method adopted is based on three research strands:
1. Study of the historical development of other disruptive technologies for civil transport aircraft,
2. Analysis of the impact of legal and commercial requirements, and
3. Technological foresight based on technology trends for aircraft currently under development.
Fly by wire and composite materials are identified as two historical examples of successful implementation of disruptive new technology. Both took decades to develop, and were initially developed for military markets. The most widely studied technology similar to FC is identified as laminar flow control. Despite more than six decades of research and arguably successful operational demonstration in the 1990s this has not been successfully transitioned to commercial products. Significant future challenges are identified in cost effective provision of the additional systems required for environmental protection and in service monitoring of FC systems particularly where multiple distributed actuators are envisaged. FC generated noise is also seen as a significant challenge. Additional complexity introduced by FC systems must also be balanced by the commercial imperative of dispatch reliability, which may impose more stringent constraints than legal (certification) requirements. It is proposed that a key driver for future successful application of FC is the likely availability of significant electrical power generation on 787 aircraft forwards. This increases the competitiveness of electrically driven FC systems compared with those using engine bleed air. At the current rate of progress it is unlikely FC will make a contribution to the next generation of single-aisle aircraft due to enter service in 2015. In the longer term, there needs to be significant movement across a broad range of systems technologies before the aerodynamic benefits of FC can be exploited.
Vitamin D deficiency has been implicated in the aetiology of infectious diseases and metabolic syndrome. These diseases are prevalent in the African and Asian-Indian populations of South Africa; however, there is limited data on 25-hydroxyvitamin D (25(OH)D) concentrations in these populations. The aim of the present study was to assess the vitamin D status and its predictors in healthy adults in Johannesburg. We assessed the vitamin D status of 730 adult African and Asian-Indian subjects residing in Johannesburg. The contributions of sun exposure, season, dietary intake of Ca and vitamin D, total body fat and body fat distribution to 25(OH)D concentrations were assessed. The concentrations of 25(OH)D were measured by HPLC. The contribution of 25(OH)D3 to total 25(OH)D concentrations was assessed. The mean age of the subjects was 42·6 (sd 13·1) years (range: 18–65). Concentrations of 25(OH)D < 30 nmol/l were found in 28·6 % of the Asian-Indian subjects in comparison with 5·1 % of the African subjects (P< 0·0001). Parathyroid hormone (PTH) concentrations were negatively associated with 25(OH)D concentrations, while season and sun exposure were positive predictors explaining 16 % of the variance in 25(OH)D concentrations (P< 0·0001) in the African subjects. In the Asian-Indian subjects, PTH concentrations were negatively associated with 25(OH)D concentrations, while male sex, season and Ca supplementation were positive predictors and explained 17 % of the variance in 25(OH)D concentrations (P< 0·0001). In the multivariate regression analysis, neither total body fat nor body fat distribution was predictive of 25(OH)D concentrations in either group. In conclusion, factors such as sun exposure, dietary supplement use and ethnicity are important determinants of plasma 25(OH)D concentrations.
The federally funded Cities Readiness Initiative (CRI) requires seamless federal, state, and local public health coordination to provide antibiotics to an entire city population within 48 hours of an aerosolized release of anthrax. We document practical lessons learned from the development and implementation of the Boston CRI plan. Key themes center on heightened emphasis on security, a new mass protection model of dispensing, neighborhood-centric clinic site selection, online training of Medical Reserve Corps volunteers, and the testing of operations through drills and exercises. Sharing such lessons can build national preparedness. (Disaster Med Public Health Preparedness. 2008;2:40–49)
The development of infrared observational facilities has revealed a number of massive stars in obscured environments throughout the Milky Way and beyond. The determination of their stellar and wind properties from infrared diagnostics is thus required to take full advantage of the wealth of observations available in the near and mid infrared. However, the task is challenging. This session addressed some of the problems encountered and showed the limitations and successes of infrared studies of massive stars.