110 research outputs found

    Palaeobiology, ecology, and distribution of stromatoporoid faunas in biostromes of the mid-Ludlow of Gotland

    Get PDF
    Six well exposed mid−Ludlow stromatoporoid−dominated reef biostromes in four localities from the Hemse Group in southeastern Gotland, Sweden comprise a stromatoporoid assemblage dominated by four species; Clathrodictyon mohicanum, “Stromatopora” bekkeri, Plectostroma scaniense, and Lophiostroma schmidtii. All biostromes investigated in this area (of approximately 30 km2) are interpreted to belong to a single faunal assemblage forming a dense accumulation of fossils that is probably the best exposed stromatoporoid−rich deposit of the Silurian. The results from this comprehensive study strengthen earlier interpretations of a combination of genetic and environmental control on growth−forms of the stromatoporoids. Growth styles are similar for stromatoporoids in all six biostromes. Differences in biostrome fabric are due to variations in the degree of disturbance by storms. The uniformity of facies and the widespread low−diversity fauna support the view that palaeoenvironmental conditions were similar across the area where these biostromes crop out, and promoted the extraordinary growth of stromatoporoids in this shallow shelf area

    Sibling bullying at 12 years and high-risk behavior in early adulthood : a prospective cohort study

    Get PDF
    Emerging evidence suggests that sibling aggression is associated with the development of high‐risk behavior. This study investigated the relationship between sibling bullying perpetration and victimization in early adolescence and high‐risk behavior in early adulthood. Sibling bullying was assessed at 12 years in 6,988 individuals from the Avon Longitudinal Study of Parents and Children, a birth cohort based in the UK and high‐risk behavioral outcomes were assessed at 18–20 years. Frequent sibling bullying perpetration predicted antisocial behavior (OR = 1.74; 95%CI, 1.38–2.20), while frequent sibling bullying victimization increased the odds of nicotine dependence (OR = 2.87; 95%CI, 1.55–5.29), even after accounting for peer bullying and parent maltreatment. Categorical analysis revealed that particularly bullies and bully‐victims were at risk of developing high‐risk behavior. Finally, this study found that adolescents who were involved in bullying perpetration across multiple contexts (home and school) had the highest odds of reporting antisocial behavior (OR = 3.05; 95%CI, 2.09–4.44), criminal involvement (OR = 2.12; 95%CI, 1.23–3.66), and illicit drug use (OR = 2.11; 95%CI, 1.44–3.08). Findings from this study suggest that sibling bullying perpetration may be a marker of or a contributory factor along the developmental trajectory to antisocial behavior problems. Intervention studies are needed in order to test whether reducing sibling bullying can alleviate long‐term adverse social and behavioral outcomes

    Evaluating the validities of different DSM-IV-based conceptual constructs of tobacco dependence

    Full text link
    AIM: To compare the concurrent and predictive validities of two subsets of DSM-IV criteria for nicotine dependence (tolerance and withdrawal; withdrawal; difficulty controlling use; and use despite harm) to the concurrent and predictive validity of the full DSM-IV criteria. DESIGN: Analysis of baseline and outcome data from three randomized clinical trials of cigarette smoking treatment. SETTING: San Francisco, California. PARTICIPANTS: Two samples of cigarette smokers (n = 810 and 322), differing with regard to baseline characteristics and treatment received, derived from three randomized clinical trials. MEASUREMENTS: DSM-IV nicotine dependence criteria were measured at baseline with a computerized version of the Diagnostic Interview Schedule for DSM-IV (DIS-IV). Additional baseline measures included the Fagerström Test of Nicotine Dependence (FTND), number of cigarettes smoked per day, breath carbon monoxide (CO) level, the Minnesota Nicotine Withdrawal Scale (MNWS), the Michigan Nicotine Reinforcement Questionnaire (M-NRQ) and the Profile of Mood States (POMS). Seven-day point-prevalence abstinence was assessed at week 12. FINDINGS: Full DSM-IV criteria displayed greater concurrent validity than either of the two subsets of criteria. However, DSM-IV symptoms accounted for only a nominal amount of the variance in baseline smoking-related characteristics and were unrelated to smoking abstinence at week 12. Cigarettes smoked per day was the only significant predictor of abstinence at week 12. CONCLUSIONS: Although the findings do not provide a compelling alternative to the full set of DSM-IV nicotine dependence criteria, its poor psychometric properties and low predictive power limit its clinical and research utility

    Measurement of (anti)deuteron and (anti)proton production in DIS at HERA

    Get PDF
    The first observation of (anti)deuterons in deep inelastic scattering at HERA has been made with the ZEUS detector at a centre-of-mass energy of 300--318 GeV using an integrated luminosity of 120 pb-1. The measurement was performed in the central rapidity region for transverse momentum per unit of mass in the range 0.3<p_T/M<0.7. The particle rates have been extracted and interpreted in terms of the coalescence model. The (anti)deuteron production yield is smaller than the (anti)proton yield by approximately three orders of magnitude, consistent with the world measurements.Comment: 26 pages, 9 figures, 5 tables, submitted to Nucl. Phys.

    The association between workplace smoking bans and self-perceived, work-related stress among smoking workers

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>There is substantial empirical evidence on the benefits of smoking bans; however, the unintended consequences of this anti-smoking measure have received little attention. This paper examines whether workplace smoking bans (WSB's) are associated with higher self-perceived, work-related stress among smoking workers.</p> <p>Methods</p> <p>A longitudinal representative sample of 3,237 individuals from the Canadian National Population Health Survey from 2000 to 2008 is used. Work-related stress is derived from a 12-item job questionnaire. Two categories of WSB's, full and partial, are included in the analysis, with no ban being the reference category. Analysis also controls for individual socio-demographic characteristics, health status, provincial and occupational fixed-effects. We use fixed-effects linear regression to control for individual time-invariant confounders, both measured and unmeasured, which can affect the relationship between WSB's and work-related stress. To examine the heterogeneous effects of WSB's, the analysis is stratified by gender and age. We check the robustness of our results by re-estimating the baseline specification with the addition of different control variables and a separate analysis for non-smokers.</p> <p>Results</p> <p>Multivariate analysis reveals a positive and statistically significant association between full <it>(ÎČ = 0.75, CI = 0.19-1.32) </it>or partial <it>(ÎČ = 0.69, CI = 0.12-1.26) </it>WSB's, and the level of self-perceived, work-related stress among smoking workers compared to those with no WSB. We also find that this association varies by gender and age. In particular, WSB's are significantly associated with higher work stress only for males and young adults (aged 18-40). No statistically significant association is found between WSB's and the level of self-perceived work-related stress among non-smoking workers.</p> <p>Conclusion</p> <p>The results of this study do not imply that WSB's are the main determinant of self-perceived, work-related stress among smokers but provides suggestive evidence that these may be positively related.</p

    Genome-wide association study across European and African American ancestries identifies a SNP in DNMT3B contributing to nicotine dependence

    Get PDF
    Cigarette smoking is a leading cause of preventable mortality worldwide. Nicotine dependence, which reduces the likelihood of quitting smoking, is a heritable trait with firmly established associations with sequence variants in nicotine acetylcholine receptor genes and at other loci. To search for additional loci, we conducted a genome-wide association study (GWAS) meta-analysis of nicotine dependence, totaling 38,602 smokers (28,677 Europeans/European Americans and 9925 African Americans) across 15 studies. In this largest-ever GWAS meta-analysis for nicotine dependence and the largest-ever cross-ancestry GWAS meta-analysis for any smoking phenotype, we reconfirmed the well-known CHRNA5-CHRNA3-CHRNB4 genes and further yielded a novel association in the DNA methyltransferase gene DNMT3B. The intronic DNMT3B rs910083-C allele (frequency = 44-77%) was associated with increased risk of nicotine dependence at P = 3.7 x 10(-8) (odds ratio (OR) = 1.06 and 95% confidence interval (CI) = 1.04-1.07 for severe vs mild dependence). The association was independently confirmed in the UK Biobank (N = 48,931) using heavy vs never smoking as a proxy phenotype (P = 3.6 x 10(-4), OR = 1.05, and 95% CI = 1.02-1.08). Rs910083-C is also associated with increased risk of squamous cell lung carcinoma in the International Lung Cancer Consortium (N = 60,586, meta-analysis P = 0.0095, OR = 1.05, and 95% CI = 1.01-1.09). Moreover, rs910083-C was implicated as a cis-methylation quantitative trait locus (QTL) variant associated with higher DNMT3B methylation in fetal brain (N = 166, P = 2.3 x 10(-26)) and a cis-expression QTL variant associated with higher DNMT3B expression in adult cerebellum from the Genotype-Tissue Expression project (N = 103, P = 3.0 x 10(-6)) and the independent Brain eQTL Almanac (N = 134, P = 0.028). This novel DNMT3B cis-acting QTL variant highlights the importance of genetically influenced regulation in brain on the risks of nicotine dependence, heavy smoking and consequent lung cancer.Peer reviewe

    The Stages of Change in the Treatment of Nicotine Dependence

    No full text
    • 

    corecore