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Adolescent smoking is a major public health problem. While the socioeconomic status (SES) of the neighbourhood and that of the family are known to play a role in smoking onset and progression, it is not clear whether it modifies the association between parental influences and adolescent behaviour. The purpose of this study is to investigate family correlates of adolescent smoking experimentation and to explore the modifying role of socioeconomic context and European geographical area in a sample of European adolescents. This is a secondary analysis of the baseline survey of the European Drug Addiction Prevention (EU-Dap) trial which took place in seven European countries and involved 7079 students. School SES was used as indicator of socioeconomic context. European countries were aggregated in two geographical areas: North-Central and South. The associations between parental, family factors, and adolescents smoking experimentation were analysed through multilevel mixed-effect logistic regression models, stratified by school SES and European geographical area. Parental smoking, permissiveness towards tobacco, family conflicts, problematic relationships, low connectedness, and low parental control were significantly associated with adolescent smoking experimentation. Paternal smoking was a stronger correlate of adolescent smoking in low SES schools, while maternal smoking in high SES schools. Parental permissiveness was a stronger correlate in low SES schools. Family conflicts and low parental control were correlates only in low SES schools. The associations did not substantially differ between European geographical areas, with the exception of parental smoking that was a stronger correlate in the North, and parental control that was a correlate only in the South of Europe. To reduce inequalities in tobacco-related outcomes, prevention efforts in low socioeconomic contexts appear to be a public health priority. Parental smoking, permissiveness, family relationships, and connectedness should be addressed in preventive programs.

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In this paper, we review the principal theoretical models through which the dielectric function of metals can be described. Starting from the Drude assumptions for intraband transitions, we show how this model can be improved by including interband absorption and temperature effect in the damping coefficients. Electronic scattering processes are described and included in the dielectric function, showing their role in determining plasmon lifetime at resonance. Relationships among permittivity, electric conductivity and refractive index are examined. Finally, a temperature dependent permittivity model is presented and is employed to predict temperature and non-linear field intensity dependence on commonly used plasmonic geometries, such as nanospheres.  相似文献   
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Variant Creutzfeldt-Jakob disease (vCJD) has been reported in 12 countries. We hypothesized that a common strain of agent is responsible for all vCJD cases, regardless of geographic origin. To test this hypothesis, we inoculated strain-typing panels of wild-type mice with brain material from human vCJD case-patients from France, the Netherlands, Italy, and the United States. Mice were assessed for clinical disease, neuropathologic changes, and glycoform profile; results were compared with those for 2 reference vCJD cases from the United Kingdom. Transmission to mice occurred from each sample tested, and data were similar between non-UK and UK cases, with the exception of the ranking of mean clinical incubation times of mouse lines. These findings support the hypothesis that a single strain of infectious agent is responsible for all vCJD infections. However, differences in incubation times require further subpassage in mice to establish any true differences in strain properties between cases.  相似文献   
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Purpose  

The transduction mechanism of the inner ear and the transmission of nerve impulses along the auditory way are highly dependent upon the cochlear oxygen supply. Several studies have considered the possibility that obstructive sleep apnea–hypopneas during sleep can interfere with these processes, and the results are not uniform. The aim of the study is to evaluate the auditory function in adult patients affected by severe obstructive sleep apnea syndrome (OSAS).  相似文献   
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