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The United States Supreme Court’s recent decision relating to violent video games revealed divisions within the scientific community about the potential for negative effects of such games as well as the need for more, higher quality research. Scholars also have debated the potential for violent games to have positive effects such as on visuospatial cognition or math ability. The current study sought to extend previous literature by using well-validated clinical outcome measures for relevant constructs, which have generally been lacking in past research. Cross-section data on aggression, visuospatial cognition, and math achievement were available for a sample of 333 (51.7 % female) mostly Hispanic youth (mean age = 12.76). Prospective 1-year data on aggression and school GPA were available for 143 (46.2 % female) of those youth. Results from both sets of analysis revealed that exposure to violent game had neither short-term nor long-term predictive influences on either positive or negative outcomes. A developmental analysis of the cross-sectional data revealed that results did not differ across age categories of older children, preadolescents or adolescents. Analysis of effect sizes largely ruled out Type II error as a possible explanation for null results. Suggestions for new directions in the field of video game research are proffered.  相似文献   
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Two synthetic cannabinoids have been identified, during a survey, as new adulterants; they might have been intended to be used as ingredients for smart drugs. The characterization of these compounds has been made by gas chromatography–mass spectrometry (GC–MS), Orbitrap high resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR), leading to the identification of WIN48098, a compound disclosed as a new adulterant in herbal and powder products, and AM679, identified in Italy for the first time.Taking into account the high number of synthetic cannabinoids seized during the last year in Italy, how quickly they appear on the illegal market and the rapidity required for analytical results, a method was developed for the simultaneous quantitation of several synthetic cannabinoids, using gas chromatography–flame ionization detection (GC–FID).  相似文献   
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Abstract

This note presents wide evidence on the relationship between population and income for 125 countries for which data was available for the period 1950–2000. The main result is that there is a weak but negative relationship between population growth and per capita GDP, as income increases population expands at a slower rate. This relationship appears to be stronger for African countries and for Asian countries before 1970.  相似文献   
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The paper questions the impact of rule-based governance in an environment with poor legal enforcement and general mistrust in the law-setting institutions. We conduct a quasi-experiment and a survey to prove that ??law on books?? can still play a role by triggering the social norm of ??obeying the law??. We furthermore expose and empirically confirm the role of the Corporate Governance Code as a signaling tool, and discuss why in a weak institutional environment the Code??s potential may be even stronger than in the developed market economies.  相似文献   
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One of the aims of fire investigations is to identify associations among accelerants according to their source. In this study, 50 gasoline samples--representing five brands--were analyzed using solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS). Chemometric procedures, such as principal component analysis (PCA) and discriminant analysis (DA), were applied to a data matrix obtained by the target compound chromatogram method, to discriminate samples according to their brand. PCA was successful in finding a natural grouping of samples according to their brand, suggesting that aromatic compounds were more useful than aliphatics for the purpose of this study. DA, if applied to aromatic compounds, gave both a classification ability and a prediction ability of 100%. The outstanding results obtained by this work provide the basis of a data matrix that could be used in real cases of arson to link a sample of unevaporated gasoline to its brand or refinery.  相似文献   
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The degree to which media contributes to body dissatisfaction, life satisfaction and eating disorder symptoms in teenage girls continues to be debated. The current study examines television, social media and peer competition influences on body dissatisfaction, eating disorder symptoms and life satisfaction in a sample of 237 mostly Hispanic girls. 101 of these girls were reassessed in a later 6-month follow-up. Neither television exposure to thin ideal media nor social media predicted negative outcomes either concurrently nor prospectively with the exception of a small concurrent correlation between social media use and life satisfaction. Social media use was found to contribute to later peer competition in prospective analysis, however, suggesting potential indirect but not direct effects on body related outcomes. Peer competition proved to be a moderate strong predictor of negative outcomes both concurrently and prospectively. It is concluded that the negative influences of social comparison are focused on peers rather than television or social media exposure.  相似文献   
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This paper tests whether factors referring to socio-economic aspects, family heritage, social interaction, habits and customs explain differences among violent and non-violent prisoners. Some of the results of the probit estimation show that economic issues are the main factors that stimulate the practice of non-violent crime. On the other hand, violent crimes results suggest that factors related to family heritage reduce this kind of crime. In relation to variables of social interaction, prisoners who were brought up in a good neighborhood have a lower probability of committing violent crimes.  相似文献   
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