253 research outputs found

    Radiation and Climate

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    The role of water-vapour photodissociation on the formation of a deep minimum in mesopause ozone

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    Smoking status in relation to serum folate and dietary vitamin intake

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    Objective Cigarette smoke itself is an abundant source of free radicals and a major cause of oxidative stress, to which plasma antioxidants function as a vital protective and counterbalancing mechanism. The objective of this study was to investigate into the relationship between smoking status and serum and dietary micronutrient concentrations. Design Cross-sectional study Subjects ' Setting 502 farmers from the Valley of Messara in Crete were randomly selected and examined. Complete three-day and 24-hr recall questionnaires were collected along with anthropometrical, physical activity and clinical data from all participating subjects. Results After adjusting for age, gender and number of fasting days adhered to per year, current smokers were found to have a lower dietary intake of vitamin C (112.1 mg vs. 136.4 mg, p = 0.03), fibre (16.6 g vs. 19.1 g, p = 0.006) and fruits and vegetables (339 g vs. 412 g, p = 0.014), while dietary vitamin B1 intake was found to be higher (1.7 mg vs. 1.4 mg, p = 0.02) in comparison to non/ex smokers. Dietary intake of meat, folate and vitami A, E, B2, B6 and B12 did not differ between the groups. Controlling age, gender, fasting days and dietary micronutrient intake, serum folate levels were found to be lower among smokers (geometric mean 15.3 nmol/L vs. 17.7 nmol/L, p = 0.023), while serum iron and vitamin B12 levels were not affected by smoking status. Conclusion Current smoking status affects dietary nutrient intake as well as plasma folate levels. The above coherence between antioxidant depletion and reduced antioxidant intake may predispose smokers to the premature development of tobacco related mortality and morbidity

    Maintained Smoking Cessation for 6 Months Equilibrates the Percentage of Sputum CD8+ Lymphocyte Cells with That of Nonsmokers

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    Little is known about the longitudinal effects of smoking cessation on sputum inflammatory cells. We aimed to investigate the changes in sputum inflammatory cells and T-lymphocyte subpopulations after 6 and 12 months smoking cessation. Induced sputum was obtained from 68 healthy smokers before and after 6 months (n = 21) and 1 year (n = 14) smoking cessation and from ten healthy never-smokers. Inflammatory cells were identified by morphology and T-lymphocyte subpopulations by flow cytometry. Sputum macrophages were decreased after 12 months of smoking cessation in comparison to baseline, while neutrophils increased. Moreover, CD8+ T-cells were decreased in smokers before smoking cessation compared to never-smokers and increased in smokers after 6 months of smoking cessation in comparison to baseline; result that was maintained after 1 year of smoking cessation. These novel findings indicate that smoking cessation can equilibrate certain inflammatory cells of smokers with those of nonsmokers, within 6 months of smoking cessation

    Attitudes towards electronic cigarettes regulation in indoor workplaces and selected public and private places: a population-based cross-sectional study

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    Background: currently, there is an intensive debate about the regulation of the use of electronic cigarettes (e-cigarettes) in indoor places. The aim of this study was to assess the attitudes toward e-cigarette use in indoor workplaces and selected public and private venues among the general population in Barcelona (Spain) in 2013-2014. Methods: this is a cross-sectional study of a representative sample of the population of Barcelona (n5736). The field work was conducted between May 2013 and February 2014. We computed the prevalence and the adjusted odds ratios(OR) derived from multivariable logistic regression models. Results: the awareness of e-cigarettes was 82.3%. Forty five percent of respondents did not agree with the use of e-cigarettes in public places and 52.3% in workplaces. The proportion of disapproval of the use of e-cigarettes in indoor places was higher at 71.5% for schools and 65.8% for hospitals and health care centers; while the prevalence of disapproval of e-cigarette use in homes and cars was lower (18.0% and 32.5%, respectively). Respondents who disagreed on the use of e-cigarettes in indoor workplaces were more likely to be older (OR51.64 and 1.97 for groups 45-64 and §65 years old, respectively), those with a high educational level (OR51.60), and never and former smokers (OR52.34 and 2.16, respectively). Increased scores in the Fagerstro¨m test for cigarette dependence were also related to increased support for their use. Conclusions: based on this population based study, half of the general population of Barcelona does not support the use of e-cigarettes in indoor workplaces and public places, with the percentage reaching 65% for use in schools, hospitals and health care centers. Consequently, there is good societal support in Spain for the politicians and legislators to promote policies restricting e-cigarettes use in workplaces and public places, including hospitality venues

    Association between unmet dental needs and school absenteeism because of illness or injury among U.S. school children and adolescents aged 6-17 years, 2011-2012

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    BACKGROUND : We assessed the prevalence of dental disease among U.S. children and adolescents aged 6–17 years, as well as the impact of unmet dental needs on school absenteeism because of illness/injury within the past 12 months. METHODS : Data were from the 2011/2012 National Survey of Children's Health (n = 65,680). Unmet dental need was defined as lack of access to appropriate and timely preventive or therapeutic dental healthcare when needed within the past 12 months. The impact of unmet dental needs on school absenteeism was measured using a multivariate generalized linear model with Poisson probability distribution (p b 0.05). RESULTS : Within the past 12 months, 21.8% (10.8 million) of all U.S. children and adolescents aged 6–17 years had “a toothache, decayed teeth, or unfilled cavities.” Of all U.S. children and adolescents aged 6–17 years, 15.8% (7.8 million) reported any unmet dental need (i.e., preventive and/or therapeutic dental need)within the past 12 months. The mean number of days of school absence because of illness/injury was higher among students with an unmet therapeutic dental need in the presence of a dental condition compared to those reporting no unmet dental need (β=0.25; p b 0.001). CONCLUSIONS : Enhanced and sustained efforts are needed to increase access to dental services among underserved U.S. children and adolescents.http://www.elsevier.com/locate/ypmed2016-03-31hb201

    Scholarly communication in transition: The use of question marks in the titles of scientific articles in medicine, life sciences and physics 1966–2005

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    The titles of scientific articles have a special significance. We examined nearly 20 million scientific articles and recorded the development of articles with a question mark at the end of their titles over the last 40 years. Our study was confined to the disciplines of physics, life sciences and medicine, where we found a significant increase from 50% to more than 200% in the number of articles with question-mark titles. We looked at the principle functions and structure of the titles of scientific papers, and we assume that marketing aspects are one of the decisive factors behind the growing usage of question-mark titles in scientific articles

    Lithium depletion in solar-like stars: no planet connection

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    We have determined precise stellar parameters and lithium abundances in a sample of 117 stars with basic properties very similar to the Sun. This sample selection reduces biasing effects and systematic errors in the analysis. We estimate the ages of our sample stars mainly from isochrone fitting but also from measurements of rotation period and X-ray luminosity and test the connection between lithium abundance, age, and stellar parameters. We find strong evidence for increasing lithium depletion with age. Our sample includes 14 stars that are known to host planets and it does not support recent claims that planet-host stars have experienced more lithium depletion than stars without planets. We find the solar lithium abundance normal for a star of its age, mass, and metallicity. Furthermore, we analyze published data for 82 stars that were reported to support an enhanced lithium depletion in planet hosts. We show that those stars in fact follow an age trend very similar to that found with our sample and that the presence of giant planets is not related to low lithium abundances. Finally, we discuss the systematic biases that led to the incorrect conclusion of an enhanced lithium depletion in planet-host stars.Comment: 11 pages, 8 figure
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