866 research outputs found

    Modelling double skin façades (DSFs) in whole-building energy simulation tools: Validation and inter-software comparison of a mechanically ventilated single-story DSF

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    Double skin façades (DSFs) have been proposed as responsive building systems to improve the building envelope's performance. Reliable simulation of DSF performance is a prerequisite to support the design and implementation of these systems in real buildings. Building energy simulation (BES) tools are commonly used by practitioners to predict the whole building energy performance, but the simulation of the thermophysical behaviour of DSFs may be challenging when carried out through BES tools. Using an exhaust-air façade case study, we analyse and assess the reliability of four popular BES tools when these are used to simulate a DSF, either through available in-built models or through custom-built representations based on zonal models. We carry out this study by comparing numerical simulations and experimental data for a series of significant thermophysical quantities, and we reflect on the performance and limitations of the different tools. The results show that no tool is outstandingly better performing over the others, but some tools offer better predictions when the focus is placed on certain thermophysical quantities, while others should be chosen if the focus is on different ones. After comparing the different models’ limitations and challenges, we conclude that BES tools can simulate the performance of DSF systems over long periods. However, their use alone is not recommended when the simulation's scope is to replicate and study short-term phenomena and dynamic aspects, such as sizing the building's HVAC system

    Replacing red and processed meat with lean or fatty fish and all-cause and cause specific mortality in Norwegian women. the Norwegian Women and Cancer Study (NOWAC): A prospective cohort study

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    Nordic Nutrition Recommendations recommend reducing red and processed meat and increasing fish consumption, but the impact of this replacement on mortality is understudied. This study investigated the replacement of red and processed meat with fish in relation to mortality. Of 83 304 women in the Norwegian Women and Cancer Study (NOWAC) study, 9420 died during a median of 21·0 years of follow-up. The hazard ratios (HR) for mortality were estimated using Cox proportional hazards regression with analyses stratified on red and processed meat intake due to non-linearity. Higher processed meat (> 30 g/d), red and processed meat (> 50 g/d), and fatty fish consumption were associated with higher mortality, while red meat and lean fish consumption were neutral or beneficial. Among women with higher processed meat intake (> 30 g/d), replacing 20 g/d with lean fish was associated with lower all-cause (HR 0·92, 95 % CI 0·89, 0·96), cancer (HR 0·92, 95 % CI 0·88, 0·97) and CVD mortality (HR 0·82, 95 % CI 0·74, 0·90), while replacing with fatty fish was associated with lower CVD mortality (HR 0·87, 95 % CI 0·77, 0·97), but not with all-cause or cancer mortality. Replacing processed meat with fish among women with lower processed meat intake (≤ 30 g/d) or replacing red meat with fish was not associated with mortality. Replacing processed meat with lean or fatty fish may lower the risk of premature deaths in Norwegian women, but only in women with high intake of processed meat. These findings suggest that interventions to reduce processed meat intake should target high consumers

    Black carbon in the atmosphere and snow, from pre-industrial times until present

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    The distribution of black carbon (BC) in the atmosphere and the deposition of BC on snow surfaces since pre-industrial time until present are modelled with the Oslo CTM2 model. The model results are compared with observations including recent measurements of BC in snow in the Arctic. The global mean burden of BC from fossil fuel and biofuel sources increased during two periods. The first period, until 1920, is related to increases in emissions in North America and Europe, and the last period after 1970 are related mainly to increasing emissions in East Asia. Although the global burden of BC from fossil fuel and biofuel increases, in the Arctic the maximum atmospheric BC burden as well as in the snow was reached in 1960s, with a slight reduction thereafter. The global mean burden of BC from open biomass burning sources has not changed significantly since 1900. With current inventories of emissions from open biomass sources, the modelled burden of BC in snow and in the atmosphere north of 65° N is small compared to the BC burden of fossil fuel and biofuel origin. From the concentration changes radiative forcing time series due to the direct aerosol effect as well as the snow-albedo effect is calculated for BC from fossil fuel and biofuel. The calculated radiative forcing in 2000 for the direct aerosol effect is 0.35 W m<sup>−2</sup> and for the snow-albedo effect 0.016 W m<sup>−2</sup> in this study. Due to a southward shift in the emissions there is an increase in the lifetime of BC as well as an increase in normalized radiative forcing, giving a change in forcing per unit of emissions of 26 % since 1950

    IDES-EDU: Comprehensive multidisciplinary education programme to accelerate the implementation of EPBD in Europe

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    This paper presents a new education and training programme on integrated energy design developed by fifteen European universities collaborating within the IDES-EDU project (2010-2013), funded by Intelligent Energy Europe. IDES-EDU aims to accelerate the implementation of the Energy Performance of Buildings Directive (EPBD) by proposing Master and Post Graduate education and training in multidisciplinary teams. To speed up transition from traditional, sub-optimised building projects with discipline-oriented, segregated budgets and operations, IDES-EDU developed comprehensive, multidisciplinary educational programmes targetting integrated project design at the interface of architecture and engineering. Taking into account local variations in climate, construction and pedagogical approaches, the programme facilitates gradual implementation towards full integration of energy efficiency in building education according to local capacity and legislation. This paper summarises the evaluation process of the first implementation of the educational material in the 15 universities, by academic staff, national industry and professional organisations, and reference students from each university. Included are expected learning outcomes, level of integration in existing curricula and alignment with theory and assessment methods. Measures for improvement as well as further dissemination to other European educational facilities are proposed. In this manner, the project will contribute to make the multiple opportunities for energy efficiency a reality.Intelligent Energy Europe programme for its financial support, Grant agreement no.IEE/09/631/SI2.55822

    Variation in the achievement of HbA1c, blood pressure and LDL cholesterol targets in type 2 diabetes in general practice and characteristics associated with risk factor control.

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    Aims To identify population, general practitioner, and practice characteristics associated with the achievement of HbA1c, blood pressure and LDL cholesterol targets, and to describe variation in the achievement of risk factor control. Methods We conducted a cross‐sectional survey of 9342 people with type 2 diabetes, 281 general practitioners and 77 general practices in Norway. Missing values (7.4%) were imputed using multiple imputation by chained equations. We used three‐level logistic regression with the achievement of HbA1c, blood pressure and LDL cholesterol targets as dependent variables, and factors related to population, general practitioners, and practices as independent variables. Results Treatment targets were achieved for HbA1c in 64%, blood pressure in 50%, and LDL cholesterol in 52% of people with type 2 diabetes, and 17% met all three targets. There was substantial heterogeneity in target achievement among general practitioners and among practices; the estimated proportion of a GPs diabetes population at target was 55–73% (10–90 percentiles) for HbA1c, 36–63% for blood pressure, and 47–57% for LDL cholesterol targets. The models explained 11%, 5% and 14%, respectively, of the total variation in the achievement of HbA1c, blood pressure and LDL cholesterol targets. Use among general practitioners of a structured diabetes form was associated with 23% higher odds of achieving the HbA1c target (odds ratio 1.23, 95% confidence interval (CI) 1.02–1.47) and 17% higher odds of achieving the LDL cholesterol target (odds ratio 1.17, 95% CI 1.01–1.35). Conclusions Clinical diabetes management is difficult, and few people meet all three risk factor control targets. The proportion of people reaching target varied among general practitioners and practices. Several population, general practitioner and practice characteristics only explained a small part of the total variation. The use of a structured diabetes form is recommended.publishedVersio

    Maternal vitamin D status in pregnancy and molar incisor hypomineralisation and hypomineralised second primary molars in the offspring at 7–9 years of age:a longitudinal study

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    Purpose: The study aimed to investigate associations between maternal vitamin D status during pregnancy and molar incisor hypomineralisation (MIH) and hypomineralised second primary molars (HSPM) among children. Methods: The study had a longitudinal design using prospectively collected data from 176 mother and child pairs. Mothers were initially recruited in a randomised controlled trial to assess a pregnancy exercise programme. Along with the 7-year follow-up, we invited the children to a dental examination. The exposure variable was maternal serum 25-hydroxyvitamin D in gestational weeks 18–22 and 32–36, categorised as insufficient (< 50 nmol/l) and sufficient (≥ 50 nmol/l). Negative binomial hurdle models were used to analyse potential associations between the exposure variables and MIH or HSPM. The models were adjusted for potential confounders. Results: Among the children (7–9 years old), 32% and 22% had at least one tooth with MIH or HSPM, respectively. A significant association was found between insufficient maternal vitamin D measured in gestational weeks 18–22 and the number of affected teeth among those with MIH at 7–9 years (adjusted RR = 1.82, 95% CI 1.13–2.93). Conclusion: Considering any limitations of the present study, it has been shown that insufficient maternal serum vitamin D at mid-pregnancy was associated with a higher number of affected teeth among the offspring with MIH at 7–9 years of age. Further prospective studies are needed to investigate whether this finding is replicable and to clarify the role of maternal vitamin D status during pregnancy and MIH, as well as HSPM, in children

    Costs and global impacts of black carbon abatement strategies

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    Abatement of particulate matter has traditionally been driven by health concerns rather than its role in global warming. Here we assess future abatement strategies in terms of how much they reduce the climate impact of black carbon (BC) and organic carbon (OC) from contained combustion. We develop global scenarios which take into account regional differences in climate impact, costs of abatement and ability to pay, as well as both the direct and indirect (snow-albedo) climate impact of BC and OC. To represent the climate impact, we estimate consistent region-specific values of direct and indirect global warming potential (GWP) and global temperature potential (GTP). The indirect GWP has been estimated using a physical approach and includes the effect of change in albedo from BC deposited on snow. The indirect GWP is highest in the Middle East followed by Russia, Europe and North America, while the total GWP is highest in the Middle East, Africa and South Asia. We conclude that prioritizing emission reductions in Asia represents the most cost-efficient global abatement strategy for BC because Asia is (1) responsible for a large share of total emissions, (2) has lower abatement costs compared to Europe and North America and (3) has large health co-benefits from reduced PM10 emissions

    Effectiveness, cost-effectiveness and cost-benefit of a single annual professional intervention for the prevention of childhood dental caries in a remote rural Indigenous community

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    Background The aim of the study is to reduce the high prevalence of tooth decay in children in a remote, rural Indigenous community in Australia, by application of a single annual dental preventive intervention. The study seeks to (1) assess the effectiveness of an annual oral health preventive intervention in slowing the incidence of dental caries in children in this community, (2) identify the mediating role of known risk factors for dental caries and (3) assess the cost-effectiveness and cost-benefit of the intervention. Methods/design The intervention is novel in that most dental preventive interventions require regular re-application, which is not possible in resource constrained communities. While tooth decay is preventable, self-care and healthy habits are lacking in these communities, placing more emphasis on health services to deliver an effective dental preventive intervention. Importantly, the study will assess cost-benefit and cost-effectiveness for broader implementation across similar communities in Australia and internationally. Discussion There is an urgent need to reduce the burden of dental decay in these communities, by implementing effective, cost-effective, feasible and sustainable dental prevention programs. Expected outcomes of this study include improved oral and general health of children within the community; an understanding of the costs associated with the intervention provided, and its comparison with the costs of allowing new lesions to develop, with associated treatment costs. Findings should be generalisable to similar communities around the world. The research is registered with the Australian New Zealand Clinical Trials Registry (ANZCTR), registration number ACTRN12615000693527; date of registration: 3rd July 2015
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