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1.
Summary. This study investigates whether there was evidence of increasing risk of still-birth with increasing paternal exposure to ionizing radiation received during employment at the Sellafield nuclear installation before the child was conceived. A significant positive association is found between the total paternal preconceptional exposure to external ionizing radiation and the risk of still-birth (after adjustment for year of birth, social class, birth order and paternal age, odds ratio at 100 mSv 1.24 (95% confidence interval 1.04–1.45)). A summary of the principal scientific findings of this study has been published in the Lancet . This paper describes in detail the statistical methods that were used in the investigation and presents the results in full.  相似文献   
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Philadelphia, then and still one of the worst governed of America’s badly governed cities, was having one of its periodic spasms of reform. A thorough study of causes was called for. Not but what the underlining cause was evident to most white Philadelphians: the corrupt semi-criminal vote of the Negro Seventh Ward…. Would it not be well, to elucidate the known causes by a scientific investigation?… With my bride of three months, I settled in one room over a cafeteria run by a College Settlement, in the worst part of the Seventh Ward. We lived there a year, in the midst of an atmosphere of dirt, drunkenness, poverty and crime. Murder sat on our doorstep, police were our government, and philanthropy dropped in with periodic advice. (DuBois, 1968/1975: 194–5 also in Logan, ed. 1944: 42) What had been borne into me during my book studies was my utter ignorance of the manual-working class, that is, of four-fifths of my countrymen…. How was I to get an opportunity of watching, day by day, in their homes and in their workshops, a sufficient number of normal manual-working families to enable me to visualize the class as a whole; to understand what was meant by chronic poverty and insecurity of livelihood. (Webb, 1926: 146–7)  相似文献   
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The posterior distribution of the likelihood is used to interpret the evidential meaning of P-values, posterior Bayes factors and Akaike's information criterion when comparing point null hypotheses with composite alternatives. Asymptotic arguments lead to simple re-calibrations of these criteria in terms of posterior tail probabilities of the likelihood ratio. (Prior) Bayes factors cannot be calibrated in this way as they are model-specific.  相似文献   
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In an anonymous survey of 195 men and 511 women (Mage = 19.8) at a small Midwestern university, 119 men (61%) and 303 women (59.5%) reported that they had engaged in sex while parked. Of these 422, 14% lost their virginity in a parked car. Having sex in parked cars was more likely to involve relational dating partners than hookups. In most recent incidents, the majority of respondents were with a serious but noncohabiting romantic partner (56.9%) in the back seat (63.4%) of a standard car (56.4%) parked out in the country (56.0%). The most common sexual acts were penile-vaginal sex and genital touching, reported by 84.6% and 57.5% of respondents, respectively. Condoms were used by 58.2% of respondents. Less than 1% of respondents reported sexually transmitted infections (STIs) or pregnancy outcomes. These data, including personal stories of memorable incidents, revealed that despite discomfort, body bumps, and risk of being caught, sex while parked was primarily a positive sexual and romantic experience for both men and women. A dark side of parked-car sex existed in that 2.5% of men and 4.3% of women reported being sexually coerced. The future study of sex in parked cars in urban environments is recommended.  相似文献   
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The most extensively studied influence on adolescent conduct problem behaviors is peers, and the literature points to genetics as one source of individual differences in peer influence. The purpose of this study was to test the hypothesis that an environmental sensitivity genetic index comprised of DRD4, 5‐HTTLPR, and GABRA2 variation would moderate the association between peer and adolescent conduct problems. Latent growth modeling was applied to PROSPER project longitudinal data from adolescents and their peers. Results showed the hypothesis was supported; adolescents with more copies of putative sensitivity alleles were more strongly influenced by their peers. The interaction form was consistent with differential susceptibility in follow‐up analyses. Strengths and weaknesses of genetic aggregates for sensitivity research are discussed.  相似文献   
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Infants’ emerging ability to move independently by crawling is associated with changes in multiple domains, including an increase in expressions of anger in situations that block infants’ goals, but it is unknown whether increased anger is specifically because of experience with being able to move autonomously or simply related to age. To examine the influence of locomotion on developmental change in anger, infants’ (N = 20) anger expressions during an arm restraint procedure were observed longitudinally at a precrawling baseline assessment and 2 and 6 weeks after the onset of crawling. Infant age at each crawling stage was unrelated to the frequency of anger expressed in response to arm restraint. At 6 weeks postcrawling onset, infants whose mothers rated them as temperamentally higher in distress to limitations, compared with those rated lower, showed a greater increase in the frequency of anger expressed during the arm restraint relative to earlier assessments and took longer to reduce the frequency of anger expressed when no longer restrained. Findings suggest that experience with autonomous crawling has an effect on anger expression, independent of age, and that a temperamental tendency to become distressed by limitations may exacerbate the effect of crawling on anger expression.  相似文献   
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In response to water quality standard violations linked to excessive organic matter (OM) and a lack of sampling data informing the Total Maximum Daily Load (TMDL), an organic matter budget was created to quantify and identify sources of OM in the lower Jordan River (Salt Lake City, UT). By sampling dissolved, fine and coarse particulate OM, as well as measuring ecosystem metabolism at seven different sites, the researchers aimed to identify the origin of excess OM, and understand pathways by which different size classes of the OM pool are generated. The dissolved fraction (DOM; 94 %) was found to be the dominant form of OM transported within the river with fine particulate organic matter (FPOM; 6 %) the second most abundant, and coarse particulate organic matter (CPOM; 1 %) transport relatively insignificant in the overall OM budget. Primary production exceeded respiratory losses in the upper river, and this, along with OM inputs from two tributaries (where water reclamation facilities discharge into the river) delivered excess OM to the impaired lower reaches. Increasing stream metabolism index (SMI) with distance downstream (>1 in the lower river) further demonstrated that transport of excessive organic matter into the lower river was from upstream sources and not due to lateral inputs. This simple approach to characterizing the organic matter budget as it relates to water quality in the Jordan River was effective and could serve as a model for future studies attempting to quantify and identify sources of OM in urban ecosystems.  相似文献   
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