359 research outputs found
Maternal alcohol and tobacco consumption and the association with their 9 to 14-year-old children's Body Mass Index
Aims: Little is known about impact of maternal alcohol and tobacco consumption on adolescents' body size. The purpose of this study was to evaluate whether maternal alcohol or tobacco consumption is associated with their children's body size in adolescence, assessed by Body Mass Index (BMI). Methods: This study was conduct in subjects recruited into the Finnish Health in Teens cohort (Fin-HIT) between 2011 and 2014. A total of 4525 subjects aged between 9 and 14 years and their mothers or female adults responsible for the children were analysed. Relative risks (RR) and 95% confidence intervals (CI) were estimated using Multinomial Logistic Regression. Results: Most children were normal weight (74.5%), 10.6% were underweight and 14.9% were overweight or obese. Among mothers, 50.6% were never smokers, 35.7% were former smokers, and 13.7% were current smokers. Alcohol consumption was classified by Alcohol Use Disorders Identification Test (AUDIT), 12.7% were abstainers (score=0), 65.0% were low-moderate drinkers (scores 1-4) and 22.3% were harmful drinkers (scores. 5). There were statistically significant associations between currently smoking mothers and children's overweight (RR=1.36; 95% CI: 1.05-1.76). There was an inverse association between maternal former smoking and children's underweight (RR=0.70; CI: 0.56-0.87) compared with never smoker mothers. Among children in puberty, abstainer mothers were more likely to have underweight children compared with low-moderate mothers (RR=1.57; 95% CI: 1.03-2.41). Conclusions: Current smoker mothers were associated with children's overweight and former-smoker mothers were inversely associated with the children's underweight. Being an abstainer mother was associated with the children's underweight in puberty stage. If other studies confirm these results, public health interventions aiming at healthy weight of adolescents should target the whole family, not only the adolescents themselves.Peer reviewe
A new aerosol wet removal scheme for the Lagrangian particle model FLEXPART v10
A new, more physically based wet removal scheme for aerosols has been implemented in the Lagrangian particle dispersion model FLEXPART. It uses three-dimensional cloud water fields from the European Centre for MediumRange Weather Forecasts (ECMWF) to determine cloud extent and distinguishes between in-cloud and below-cloud scavenging. The new in-cloud nucleation scavenging depends on cloud water phase (liquid, ice or mixed-phase), based on the aerosol's prescribed efficiency to serve as ice crystal nuclei and liquid water nuclei, respectively. The impaction scavenging scheme now parameterizes below-cloud removal as a function of aerosol particle size and precipitation type (snow or rain) and intensity. Sensitivity tests with the new scavenging scheme and comparisons with observational data were conducted for three distinct types of primary aerosols, which pose different challenges for modeling wet scavenging due to their differences in solubility, volatility and size distribution: (1) Cs-137 released during the Fukushima nuclear accident attached mainly to highly soluble sulphate aerosol particles, (2) black carbon (BC) aerosol particles, and (3) mineral dust. Calculated e-folding lifetimes of accumulation mode aerosols for these three aerosol types were 11.7, 16.0, and 31.6 days respectively, when well mixed in the atmosphere. These are longer lifetimes than those obtained by the previous removal schem, and, for mineral dust in particular, primarily result from very slow in-cloud removal, which globally is the primary removal mechanism for these accumulation mode particles. Calculated e-folding lifetimes in FLEXPART also have a strong size dependence, with the longest lifetimes found for the accumulation-mode aerosols. For example, for dust particles emitted at the surface the lifetimes were 13.8 days for particles with 1 aem diameter and a few hours for 10 aem particles. A strong size dependence in below-cloud scavenging, combined with increased dry removal, is the primary reason for the shorter lifetimes of the larger particles. The most frequent removal is in-cloud scavenging (85% of all scavenging events) but it occurs primarily in the free troposphere, while below-cloud removal is more frequent below 1000m (52% of all events) and can be important for the initial fate of species emitted at the surface, such as those examined here. For assumed realistic in-cloud removal efficiencies, both BC and sulphate have a slight overestimation of observed atmospheric concentrations (a factor of 1.6 and 1.2 respectively). However, this overestimation is largest close to the sources and thus appears more related to overestimated emissions rather than underestimated removal. The new aerosol wet removal scheme of FLEXPART incorporates more realistic information about clouds and aerosol properties and it compares better with both observed lifetimes and concentration than the old scheme.Peer reviewe
Hes-6, an inhibitor of Hes-1, is regulated by 17β-estradiol and promotes breast cancer cell proliferation
Snow albedo and its sensitivity to changes in deposited light-absorbing particles estimated from ambient temperature and snow depth observations at a high-altitude site in the Himalaya
Snow darkening by deposited light-absorbing particles (LAP) accelerates snowmelt and shifts the snow meltout date (MOD). Here, we present a simple approach to estimate the snow albedo variability due to LAP deposition and test this method with data for 2 seasons (February-May 2016 and December 2016-June 2017) at a high-altitude valley site in the Central Himalayas, India. We derive a parameterization for the snow albedo that only depends on the daily observations of average ambient temperature and change in snow depth, as well as an assumed average concentration of LAP in snow precipitation. Linear regression between observed and parameterized albedo for the base case assuming an equivalent elemental carbon concentration [ECeq] of 100 ng g(-1) in snow precipitation yields a slope of 0.75 and a Pearson correlation coefficient r(2) of 0.76. However, comparing the integrated amount of shortwave radiation absorbed during the winter season using observed albedo versus base case albedo resulted in rather small differences of 11% and 4% at the end of Seasons 1 and 2, respectively. The enhanced energy absorbed due to LAP at the end of the 2 seasons for the base case scenario (assuming an [ECeq] of 100 ng g(-1) in snow precipitation) was 40% and 36% compared to pristine snow. A numerical evaluation with different assumed [ECeq] in snow precipitation suggests that the relative sensitivity of snow albedo to changes in [ECeq] remains rather constant for the 2 seasons. Doubling [ECeq] augments the absorption by less than 20%, highlighting that the impact on a MOD is small even for a doubling of average LAP in snow precipitation.Peer reviewe
Simultaneous measurements of aerosol size distributions at three sites in the European high Arctic
19 pages, 9 figures, 1 tableAerosols are an integral part of the Arctic climate system due to their direct interaction with radiation and indirect interaction through cloud formation. Understanding aerosol size distributions and their dynamics is crucial for the ability to predict these climate relevant effects. When of favourable size and composition, both long-rangetransported-and locally formed particles-may serve as cloud condensation nuclei (CCN). Small changes of composition or size may have a large impact on the low CCN concentrations currently characteristic of the Arctic environment. We present a cluster analysis of particle size distributions (PSDs; size range 8-500 nm) simultaneously collected from three high Arctic sites during a 3-year period (2013-2015). Two sites are located in the Svalbard archipelago: Zeppelin research station (ZEP; 474 m above ground) and the nearby Gruvebadet Observatory (GRU; about 2 km distance from Zeppelin, 67 m above ground). The third site (Villum Research Station at Station Nord, VRS; 30 m above ground) is 600 km west-northwest of Zeppelin, at the tip of northeastern Greenland. The GRU site is included in an inter-site comparison for the first time. K-means cluster analysis provided eight specific aerosol categories, further combined into broad PSD classes with similar characteristics, namely pristine low concentrations (12 %-14 % occurrence), new particle formation (16 %-32 %), Aitken (21 %-35 %) and accumulation (20 %-50 %). Confined for longer time periods by consolidated pack sea ice regions, the Greenland site GRU shows PSDs with lower ultrafine-mode aerosol concentrations during summer but higher accumulation-mode aerosol concentrations during winter, relative to the Svalbard sites. By association with chemical composition and cloud condensation nuclei properties, further conclusions can be derived. Three distinct types of accumulation-mode aerosol are observed during winter months. These are associated with sea spray (largest detectable sizes, > 400 nm), Arctic haze (main mode at 150 nm) and aged accumulation-mode (main mode at 220 nm) aerosols. In contrast, locally produced particles, most likely of marine biogenic origin, exhibit size distributions dominated by the nucleation and Aitken mode during summer months. The obtained data and analysis point towards future studies, including apportioning the relative contribution of primary and secondary aerosol formation pro cesses and elucidating anthropogenic aerosol dynamics and transport and removal processes across the Greenland Sea. In order to address important research questions in the Arctic on scales beyond a singular station or measurement events, it is imperative to continue strengthening international scientific cooperationThis research has been supported by the Spanish Ministry of Economy through project BIO-NUC (CGL2013-49020-R), PI-ICE (CTM2017-89117-R) and the Ramon y Cajal fellowship (RYC-2012-11922). The research leading to these results has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement no. 654109, the Danish Council for Independent Research (project NUMEN, DFF-FTP-4005-00485B) and previously from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 262254. The work at Villum Research Station, Station Nord, was financially supported by the Danish Environmental Protection Agency via the MIKA/DANCEA funds for Environmental Support to the Arctic Region. The Villum Foundation funded the construction of Villum Research Station, Station Nord. CCN measurements are supported by a KOPRI program (PN19081), funded by a National Research Foundation of Korea grant (NRF-2016M1A5A1901769). The authors acknowledge financial support (to David C. S. Beddows) from the Natural Environment Research Council's funding of the National Centre for Atmospheric Science (NCAS) (grant number R8/H12/83/011)Peer Reviewe
Light-absorption of dust and elemental carbon in snow in the Indian Himalayas and the Finnish Arctic
Light-absorbing impurities (LAIs) deposited in snow have the potential to substantially affect the snow radiation budget, with subsequent implications for snow melt. To more accurately quantify the snow albedo, the contribution from different LAIs needs to be assessed. Here we estimate the main LAI components, elemental carbon (EC) (as a proxy for black carbon) and mineral dust in snow from the Indian Himalayas and paired the results with snow samples from Arctic Finland. The impurities are collected onto quartz filters and are analyzed thermal-optically for EC, as well as with an additional optical measurement to estimate the light-absorption of dust separately on the filters. Laboratory tests were conducted using substrates containing soot and mineral particles, especially prepared to test the experimental setup. Analyzed ambient snow samples show EC concentrations that are in the same range as presented by previous research, for each respective region. In terms of the mass absorption cross section (MAC) our ambient EC surprisingly had about half of the MAC value compared to our laboratory standard EC (chimney soot), suggesting a less light absorptive EC in the snow, which has consequences for the snow albedo reduction caused by EC. In the Himalayan samples, larger contributions by dust (in the range of 50% or greater for the light absorption caused by the LAI) highlighted the importance of dust acting as a light absorber in the snow. Moreover, EC concentrations in the Indian samples, acquired from a 120 cm deep snow pit (possibly covering the last five years of snow fall), suggest an increase in both EC and dust deposition. This work emphasizes the complexity in determining the snow albedo, showing that LAI concentrations alone might not be sufficient, but additional transient effects on the light-absorbing properties of the EC need to be considered and studied in the snow. Equally as imperative is the confirmation of the spatial and temporal representativeness of these data by comparing data from several and deeper pits explored at the same time.Peer reviewe
The study of the mercury cycle in polar regions: An international study in Ny-Alesund, Svalbard
Mercury (Hg) is a toxic pollutant and it can be strongly accumulated in the food chain, especially in Polar Regions. This paper presents a part of the work that has been on-going for 3-4 years in Ny-Alesund, Svalbard within the frame of an international collaboration. In Ny-Alesund in spring 2003, the atmospheric chemistry of mercury has been studied so as to better understand the formation of oxidized mercury species in the atmosphere that could be deposited onto snow surfaces. The role of snow as a potential source of mercury to the atmosphere or as a sink has also been approached to better understand the behavior of this metal. Chemical and biological processes seem to play a major role in Hg storage in snow. When melting, snow could be a major source of Hg into the various ecosystems and this toxin could therefore be accumulated into the food chain
High-precision mapping of protein–protein interfaces: an integrated genetic strategy combining en masse mutagenesis and DNA-level parallel analysis on a yeast two-hybrid platform
Understanding networks of protein–protein interactions constitutes an essential component on a path towards comprehensive description of cell function. Whereas efficient techniques are readily available for the initial identification of interacting protein partners, practical strategies are lacking for the subsequent high-resolution mapping of regions involved in protein–protein interfaces. We present here a genetic strategy to accurately map interacting protein regions at amino acid precision. The system is based on parallel construction, sampling and analysis of a comprehensive insertion mutant library. The methodology integrates Mu in vitro transposition-based random pentapeptide mutagenesis of proteins, yeast two-hybrid screening and high-resolution genetic footprinting. The strategy is general and applicable to any interacting protein pair. We demonstrate the feasibility of the methodology by mapping the region in human JFC1 that interacts with Rab8A, and we show that the association is mediated by the Slp homology domain 1
Core level ionization dynamics in small molecules studied by x-ray-emission threshold-electron coincidence spectroscopy
T wave abnormalities, high body mass index, current smoking and high lipoprotein (a) levels predict the development of major abnormal Q/QS patterns 20 years later. A population-based study
BACKGROUND: Most studies on risk factors for development of coronary heart disease (CHD) have been based on the clinical outcome of CHD. Our aim was to identify factors that could predict the development of ECG markers of CHD, such as abnormal Q/QS patterns, ST segment depression and T wave abnormalities, in 70-year-old men, irrespective of clinical outcome. METHODS: Predictors for development of different ECG abnormalities were identified in a population-based study using stepwise logistic regression. Anthropometrical and metabolic factors, ECG abnormalities and vital signs from a health survey of men at age 50 were related to ECG abnormalities identified in the same cohort 20 years later. RESULTS: At the age of 70, 9% had developed a major abnormal Q/QS pattern, but 63% of these subjects had not been previously hospitalized due to MI, while 57% with symptomatic MI between age 50 and 70 had no major Q/QS pattern at age 70. T wave abnormalities (Odds ratio 3.11, 95% CI 1.18–8.17), high lipoprotein (a) levels, high body mass index (BMI) and smoking were identified as significant independent predictors for the development of abnormal major Q/QS patterns. T wave abnormalities and high fasting glucose levels were significant independent predictors for the development of ST segment depression without abnormal Q/QS pattern. CONCLUSION: T wave abnormalities on resting ECG should be given special attention and correlated with clinical information. Risk factors for major Q/QS patterns need not be the same as traditional risk factors for clinically recognized CHD. High lipoprotein (a) levels may be a stronger risk factor for silent myocardial infarction (MI) compared to clinically recognized MI
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