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741.
The purpose of this study was to investigate the relationships among self-efficacy for condom use during distress (SE-Condom Distress), self-efficacy related to general HIV prevention skills (SE-HIV), and HIV risk behaviors, attitudes, and knowledge. Two hundred and twenty two adolescents with psychiatric disorders between 13 and 18 years-old participated. Participants completed measures related to HIV Self-Efficacy, HIV Attitudes, and Sexual Behaviors. Self-efficacy for condom use during distress (SE-Condom Distress) was significantly associated with more HIV protective behaviors. Controlling for observed covariates, SE-Condom Distress was the only variable significantly associated with consistent condom use in a multiple logistic regression (OR=2.43). Self-efficacy regarding condom use during affective arousal is closely associated with HIV-related attitudes and behaviors. Clinicians need to be alert to subtle signs of distress as adolescents contemplate safer sexual behavior.  相似文献   
742.
Harold D. Clarke and Marianne C. Stewart School of Economic, Political and Policy Sciences, University of Texas at Dallas, Richardson, TX 75083 e-mail: hclarke{at}utdallas.edu e-mail: mstewart{at}utdallas.edu Paul Whiteley Department of Government, University of Essex, Colchester, England CO4 3SQ e-mail: whiteley{at}essex.ac.uk e-mail: sanders{at}essex.ac.uk (Corresponding author) Although political scientists have begun to investigate theproperties of Internet surveys, much remains to be learned aboutthe utility of the Internet mode for conducting major surveyresearch projects such as national election studies. This paperaddresses this topic by presenting the results of an extensivesurvey comparison experiment conducted as part of the 2005 BritishElection Study. Analyses show statistically significant, butgenerally small, differences in distributions of key explanatoryvariables in models of turnout and party choice. Estimatingmodel parameters reveals that there are few statistically significantdifferences between coefficients generated using the in-personand Internet data, and the relative explanatory power of rivalmodels is virtually identical for the two types of data. Ingeneral, the in-person and Internet data tell very similar storiesabout what matters for turnout and party preference in Britain.Determining if similar findings obtain in other countries shouldhave high priority on the research agenda for national electionstudies. Authors' note: We thank the U.K. Economics and Social ResearchCouncil (ESRC) and Gary Williams, Senior Science Manager atthe ESRC, for their generous support of, and interest in, thisproject. We also thank the editor and anonymous reviewers forhelpful comments and suggestions.  相似文献   
743.
We show that the optimal prize structure of symmetric n-player Tullock tournaments assigns the entire prize pool to the winner, provided that a symmetric pure strategy equilibrium exists. If such an equilibrium fails to exist under the winner-take-all structure, we construct the optimal prize structure which improves existence conditions by dampening efforts. If no such optimal equilibrium exists, no symmetric pure strategy equilibrium induces positive efforts.  相似文献   
744.
We investigate how material and symbolic campaign appeals may motivate segments of the electorate to be more engaged with the unfolding presidential campaign; this engagement is a first step toward bringing these populations into an electoral coalition. We pair two massive new data collections—the National Annenberg Election Study capturing public opinion across an entire campaign and The Wisconsin Advertising Project recording and cataloging the political commercials aired by campaigns—to examine how the candidates’ choice of issues affects who gets into the game. We find evidence that appeals to symbolic interests are more likely than appeals to material interest to selectively engage targeted groups.  相似文献   
745.
On 15 March 2012 the European Court of Human Rights (the Court) issued its first judgment addressing the differential treatment of same‐sex and opposite‐sex couples in respect of the adoption of a child. 1 The Court held that excluding same‐sex couples in civil partnerships, who have no legal right to marry, from adoption provisions available to married opposite‐sex couples does not violate rights guaranteed by the European Convention on Human Rights (the Convention). I argue that the Court's reasoning in Gas and Dubois v France is unpersuasive and unsustainable in light of its wider case law.  相似文献   
746.
Surface coatings that can help deter and solve gun crime are described. These nanoengineered coatings have been applied and evaluated on brass cartridge cases, where they increase associative forensic evidence through nanotag donation to the handler and the retention of handler's DNA. In future we expect this approach to be used for other surfaces and conditions.  相似文献   
747.
Pearson correlation coefficients were applied for the objective comparison of 30 black gel pen inks analysed by laser desorption ionization mass spectrometry (LDI-MS). The mass spectra were obtained for ink lines directly on paper using positive and negative ion modes at several laser intensities. This methodology has the advantage of taking into account the reproducibility of the results as well as the variability between spectra of different pens. A differentiation threshold could thus be selected in order to avoid the risk of false differentiation. Combining results from positive and negative mode yielded a discriminating power up to 85%, which was better than the one obtained previously with other optical comparison methodologies. The technique also allowed discriminating between pens from the same brand.  相似文献   
748.
This paper demonstrates a numerical pattern recognition method applied to curvilinear image structures. These structures are extracted from physical cross-sections of cast internal pistol barrel surfaces. Variations in structure arise from gun design and manufacturing method providing a basis for discrimination and identification. Binarised curvilinear land transition images are processed with fast Fourier transform on which principal component analysis is performed. One-way analysis of variance (95% confidence interval) concludes significant differentiation between 11 barrel manufacturers when calculating weighted Euclidean distance between any trio of land transitions and an average land transition for each barrel in the database. The proposed methodology is therefore a promising novel approach for the classification and identification of firearms.  相似文献   
749.
Several studies have indicated that there are potential environmental sources of particles resembling inorganic primer found in gunshot residues (GSR); as a consequence examiners are reluctant to unambiguously assign the origin of inorganic particles. If organic gunshot residues (OGSR) were found in combination with inorganic particles, the possibility of environmental sources could be potentially eliminated, thereby significantly enhancing the strength of the evidence. Methods have been previously described whereby GSR specimens can be analysed for the presence of OGSR or inorganic GRS (IGSR). However, no methods have been reported that allow the analysis of both OGSR and IGSR on the same specimen. Described in this article is a direct method using desorption electrospray ionisation-mass spectrometry (DESI-MS) for the detection of methyl centralite (MC), ethyl centralite (EC) and diphenylamine (DPA) on adhesive tape GSR stubs typically used for scanning electron microscopy-energy-dispersive X-ray (SEM-EDX) analysis. The optimisation of numerous parameters was conducted using an experimental design. The results indicate that direct analysis of these organic components of GSR is possible although some limitations were also identified. This initial investigation has also indicated that subjecting stubs to DESI analysis does not interfere with subsequent SEM-EDX analysis of primer residues; therefore the technique described herein allows a comprehensive examination of GSR that would be highly probative in the event that both OGSR and IGSR are detected in the same specimen.  相似文献   
750.
Low self-control has emerged as a consistent and strong predictor of antisocial and delinquent behaviors. Using the twin subsample of the National Longitudinal Study of Adolescent Health (Add Health), genetic analyses were conducted to examine the genetic and environmental contributions to low self-control and offending as well as to their relationship with one another. The results revealed that low self-control and criminal behaviors are influenced by genetic and nonshared environmental factors with the effects of shared environmental factors being negligible. In addition, the co-variation between low self-control and criminal behaviors appears to be largely due to common genetic and nonshared environmental factors operating on both phenotypes. The implications of these findings on the current understanding of Gottfredson and Hirschi??s general theory of crime are discussed.  相似文献   
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