Modelling of a standard gas mixtures generator with computational fluid dynamics

Monitoring VOC for climate change and for indoor and outdoor air quality at trace level concentrations need reference standard materials at high metrological performance. To improve this performance, the description of phenomena involved in mixtures generation by rigorous models is mandatory. A model to describe diffusion cells of a primary generator was developed and validated with experimental data. A good agreement was found between the uncertainties of measurements and calculations

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Interventions using behavioural insights to influence children's diet-related outcomes: a systematic review

The global prevalence of children with overweight and obesity continues to rise. Obesity in childhood has dire long-term consequences on health, social and economic outcomes. Promising interventions using behavioural insights to address obesity in childhood have emerged. This systematic review examines the effectiveness and health equity implications of interventions using behavioural insights to improve children's diet-related outcomes. The search strategy included searches on six electronic databases, reference lists of previous systematic reviews and backward searching of all included studies. One-hundred and eight papers describing 137 interventions were included. Interventions using behavioural insights were effective at modifying children's diet-related outcomes in 74% of all included interventions. The most promising approaches involved using incentives, changing defaults and modifying the physical environment. Information provision alone was the least effective approach. Health equity implications were rarely analysed or discussed. There was limited evidence of the sustainability of interventions-both in relation to their overall effectiveness and cost-effectiveness. The limited evidence on health equity, long-term effectiveness and the cost-effectiveness of these interventions limit what can be inferred for policymakers. This review synthesises the use of behavioural insights to improve children's diet-related outcomes, which can be used to inform future interventions

In-use Energy Performance Study Of Automated Smart Homes

Domestic energy demand has been high on the carbon reduction agenda for some time. Today new homes are being designed following the “fabric first” principle which is reducing heat demand, but it is shifting the design challenge to ventilation. Further energy reductions and comfort improvements are needed. It is frequently proposed that automated control systems can achieve this. However, the technologies involved are currently considered expensive and complicated. There is little published evidence of how these types of systems perform in use, which leads to scepticism. This research study aims to test the hypothesis that automated demand-controlled heating and ventilation can provide a good indoor environment while reducing energy consumption in “real-life” homes. A year-long case study was conducted using six occupied, neighbouring dwellings installed with a low-cost automated building control system. The energy consumption figures recorded were compared to the values predicted by the Standard Assessment Procedure and by a Dynamic Simulation Model, and compared to Passivhaus standard. Significant savings have been identified. The results of this study show that an automated control system can lead to very low energy, and hence low carbon homes at a price-point that would incentivise widespread role out. This means that such systems have the potential to make a considerable contribution to reducing the carbon footprint of housing stock, and hence to meeting carbon reduction targets

The benefits and challenges of taxing sugar in a small island state: an interrupted time series analysis

Background: Beverage and food taxes have become a popular ‘best buy’ public health intervention in the global battle to tackle noncommunicable diseases. Though many countries have introduced taxes, mainly targeting products containing sugar, there is great heterogeneity in tax design. For taxes levied as import tariffs, there is limited evidence of effectiveness in changing the price and sale of taxed products, while the evidence base is stronger for excise taxes levied as a fixed amount per quantity of product. This paper examines the effect of the Bermuda Discretionary Foods Tax, which was based on import tariff changes, on retail prices and sales of sugar-sweetened beverages (SSBs), and on selected fruits and vegetables that benefited from a tariff reduction. Methods: We used weekly electronic point-of-sale data from a major food retailer in Bermuda. We assessed historical weekly sales and price data using an interrupted time series design on 2,703 unique products between the dates of January 2018 through January 2020, covering 103 weeks. Results: By January 2020, the average price per ounce of SSBs increased by 26.0%, while the price of untaxed beverages (including waters and non-added sugar drinks) remained constant. The increasing price of SSBs was the sole observable structural driver of SSB market share, responsible for a decrease in the market share by nearly eight percentage points by the end of the study period. The subsidy on fruits and vegetables was ineffective in changing prices and sales, due to the relatively small 5% import tax decrease. Conclusions: The tax was largely passed through to consumers. However, several factors mitigated the impact of the tax on the prices paid for SSBs by consumers, including the specific design of the tax, price promotions and consumer responses. The experience of Bermuda provides important lessons for the planning of similar taxes in the future

Episiotomy in Southern Brazil: prevalence, trend, and associated factors

OBJECTIVE To identify and analyze the prevalence, trend, and factors associated with episiotomy in Rio Grande, in the state of Rio Grande do Sul, Southern Brazil. METHODS A single, standardized questionnaire was applied to all pregnant women, residents in the municipality of Rio Grande, who had children in local hospitals between January 1 and December 12 of the years 2007, 2010, 2013, 2016 e 2019. Demographic and socioeconomic characteristics were investigated, as well as the assistance received during pregnancy and delivery. Chi-square test was used to compare proportions and Poisson regression with robust variance adjustment was used for multivariable analysis. Prevalence ratio (PR) was used as effect measure. RESULTS Among the 12,645 births that occurred in the five years, 5,714 (45.2%) were vaginal delivery. Of these mothers, 2,930 (51.3%; 95%CI: 50.0%–52.6%) underwent episiotomy. Over this period, the episiotomy rate decreased from 70.9% (68.4–73.5) in 2007 to 19.4% (17.1–21.7) in 2019. Adjusted analysis showed a high PR of episiotomy occurrence among women who were young (PR = 2.23; 95%CI: 1.89–2.63), had higher education (PR = 1.21; 95%Cl: 1.03–1.42), had a higher family income (PR = 1.25; 95%CI: 1.10–1.41), were primiparous (PR = 3.41; 95%CI: 2.95–3.95), had prenatal care in the private sector (PR = 1.25; 95%CI: 1.07–1.46), had oxytocin-induced labor (PR = 1.18; 95%CI:1.09–1.27), underwent forceps (PR = 1.32; 95%CI: 1.16–1.50), and whose newborn weighed 4,000 g or more (PR = 1.43; 95%CI: 1.14–1.80). CONCLUSION Although the prevalence of episiotomy fell sharply within the studied period, its occurrence is more likely among women at lower risk of birth complications

Mercury acetate produced by metallic mercury subjected to acoustic cavitation in a solution of acetic acid in water.

Mercury acetate (MA) can be obtained by metallic mercury immersed in a mixture of deionised, bidistillated water (dbw) and acetic acid. We show that MA crystallization time is drastically reduced if the previous mixtures are subjected to acoustic cavitation. The largest quantity of crystals is obtained by a concentration of acetic acid of about 7% in volume. NMR analysis of identical mixtures in the presence of mercury, performed as soon as possible after cavitation, showed the largest quantity of mercury acetate molecules, for the same concentration of acetic acid of 7% in volume