451 research outputs found

    Theoretical prediction of spectral and optical properties of bacteriochlorophylls in thermally disordered LH2 antenna complexes

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    A general approach for calculating spectral and optical properties of pigment-protein complexes of known atomic structure is presented. The method, that combines molecular dynamics simulations, quantum chemistry calculations and statistical mechanical modeling, is demonstrated by calculating the absorption and circular dichroism spectra of the B800-B850 BChls of the LH2 antenna complex from Rs. molischianum at room temperature. The calculated spectra are found to be in good agreement with the available experimental results. The calculations reveal that the broadening of the B800 band is mainly caused by the interactions with the polar protein environment, while the broadening of the B850 band is due to the excitonic interactions. Since it contains no fitting parameters, in principle, the proposed method can be used to predict optical spectra of arbitrary pigment-protein complexes of known structure.Comment: ReVTeX4, 11 pages, 9 figures, submitted to J. Chem. Phy

    a cross-sectional study in six European cities

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    Background: The relationship between socioeconomic position (SEP) and adolescent physical activity is uncertain, as most evidence is limited to specific settings and a restricted number of SEP indicators. This study aimed to assess the magnitude of socioeconomic differences in adolescent vigorous physical activity (VPA) across various European countries using a wide range of SEP indicators, including family-based (education, family affluence, perceived social standing, parents’ employment, housing tenure) and adolescent-based (academic performance and pocket money) ones. Methods: We used data from a survey among 10,510 students aged 14–17 from 50 schools in six European cities: Namur (BE), Tampere (FI), Hannover (DE), Latina (IT), Amersfoort (NL), Coimbra (PT). The questionnaire included socio-demographic characteristics and the amount of time spent in VPA. Results: The mean time spent practicing VPA was 60.4 min per day, with lower values for Namur (BE) and Latina (IT), and higher values for Amersfoort (NL). In the multivariable analysis, both categories of SEP indicators (family-based and adolescent based indicators) were independently associated with VPA. For each SEP indicator, lower levels of VPA were recorded in lower socioeconomic groups. In the total sample, each additional category of low SEP was associated with a decrease in mean VPA of about 4 min per day. Conclusions: This study showed that across European cities adolescent VPA is positively related to both family-based SEP and adolescents’ own SEP. When analysing socioeconomic differences in adolescent VPA, one should consider the use of multiple indicators of SEP.publishersversionpublishe

    Good practice in mental health care for socially marginalised groups in Europe: a qualitative study of expert views in 14 countries

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    This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

    The role of parental smoking on adolescent smoking and its social patterning: a cross-sectional survey in six European cities

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    Background Several studies have observed socio-economic (SE) inequalities in smoking among adolescents, but its causes are not fully understood. This study investigates the association between parental and adolescent smoking, and whether this association is socially patterned. Methods We used data from a survey administered in 2013 to students aged 14-17 years old of six European cities (n = 10 526). Using multilevel mixed-effects logistic regression, we modelled the probability of being a daily smoker as a function of parental smoking and SE status. We tested whether the smoking association differed across social strata. Results The prevalence of parental smoking was higher in low SE status adolescents. Boys and girls were more likely to smoke if they have a father [boys: adjusted odds ratio (AOR) = 1.90, 95% CI = 1.47-2.46; girls: AOR = 1.42, 95% CI = 1.09-1.86] and mother (boys: AOR = 1.77, 95% CI = 1.35-2.31; girls: AOR = 3.36, 95% CI = 2.56-4.40) who smoked. Among boys, the odds of smoking when having a smoking parent were higher in lower SE classes. However, this was not statistically significant, nor was it observed among girls. Conclusions Adolescents are more likely to smoke when their father and mother smoke. Although the susceptibility to parental smoking was similar across social classes, SE differences in parental smoking contribute to the transmission of SE inequalities in smokin

    As variedades de arroz vermelho brasileiras.

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    The Association Between Smoke-Free School Policies and Adolescents’ Perceived Antismoking Norms: Moderation by School Connectedness

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    © The Author(s) 2019. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco.BACKGROUND: Many European schools implement smoke-free school policies (SFSPs). SFSPs may decrease adolescent smoking by causing adolescents to perceive stronger anti-smoking norms, yet there exists no quantitative evidence that indicates for which norms and for whom such effects may occur. This study therefore assessed to what extent adolescents' perceived anti-smoking norms among best friends, teachers, and society at large were associated with SFSPs, and whether these associations were moderated by adolescents' level of school connectedness. METHODS: Survey data were collected in 2016/2017 on 10,653 14-16-year-old adolescents and 315 staff members in 55 schools from seven European cities. Associations of adolescent-perceived SFSPs and staff-reported SFSPs with best friend, teacher and societal anti-smoking norms were estimated in multilevel logistic regression models, adjusted for demographics and school-level smoking prevalence. We tested for interaction between school connectedness and SFSPs. RESULTS: Adolescent-perceived SFSPs were positively associated with anti-smoking norms by teachers (OR:1.46, 95%CI:1.15-1.85), were negatively associated with anti-smoking norms by best friends (OR:0.81, 95%CI:0.67-0.99), but were not significantly associated with anti-smoking norms by society at large (OR:0.87, 95%CI:0.74-1.02). All interaction tests between adolescent-perceived SFSPs and school connectedness were non-significant. Staff-reported SFSPs were not associated with any norm and showed no significant interaction with school connectedness. CONCLUSIONS: We found that SFSPs are associated with adolescents' perception of more anti-smoking norms by teachers, but less anti-smoking norms by best friends, irrespective of adolescents' level of school connectedness. IMPLICATIONS: Smoke-free school policies, just as many other tobacco control policies, are assumed to foster adolescents' perception of anti-smoking norms. Still, current evidence does not demonstrate which anti-smoking norms may be influenced by SFSPs and whether this influence is equal for adolescents with different levels of school connectedness. This study suggests that SFSPs foster adolescents' perception of anti-smoking norms by teachers, but may concurrently lead to the perception of less anti-smoking norms by best friends, irrespective of adolescents' school connectedness. SFSPs may therefore need to be complemented with interventions that target anti-smoking norms in adolescent peer groups.authorsversionpublishe
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