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Research on U.S. congressional elections has placed great emphasis on the role of competitiveness, which is associated with high levels of campaign spending, media coverage, and interest group and party involvement. Competitive campaigns have been found to increase citizens' participation, engagement and learning. However, little is known about whether the effects of competitive campaigns have enduring consequences for citizens' attitudes and behavior. Analyzing a survey of citizens conducted one year after the 2006 congressional elections that includes an oversample of respondents from competitive House races, we examine whether exposure to a competitive House campaign affects voters' political knowledge and political interest as well as their consumption of political news. We find that competitive elections have positive effects that endure for at least a year beyond the campaign season, reinforcing the idea that political competition plays a robust role in American representative democracy.  相似文献   
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In late February 2008, law enforcement officials in Las Vegas, Nevada, discovered in a hotel room, a copy of The Anarchist Cookbook, suspected castor beans and a "white powder" thought to be a preparation of ricin. Ricin is a deadly toxin from the seed of the castor bean plant (Ricinus communis). The United States regulates the possession, use, and transfer of ricin and it is the only substance considered a warfare agent in both the Chemical and the Biological Weapons Conventions. Six samples obtained from the hotel room were analyzed by laboratories at the Centers for Disease Control and Prevention using a panel of biological and mass spectrometric assays. The biological assays (real time-PCR, time resolved fluorescence and cytotoxicity) provided presumptive evidence of active ricin in each of the samples. This initial screen was followed by an in-depth analysis using a novel, state-of-the-art mass spectrometry-based ricin functional assay and high sensitivity tandem mass spectrometry for protein identification. Mass spectrometric analysis positively identified ricin and confirmed that in each of the samples it was enzymatically active. The tandem mass spectrometry analysis used here is the most selective method available to detect ricin toxin. In each sample, ricin was unequivocally identified along with other R. communis plant proteins, including the highly homologous protein RCA120. Although database searches using tandem mass spectra acquired from the samples indicated that additional controlled substances were not present in these samples, the mass spectrometric results did provide extensive detail about the sample contents. To the best of our knowledge following a review of the available literature, this report describes the most detailed analysis of a white powder for a public health or forensic investigation involving ricin.  相似文献   
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Conflicted parental separation is associated with risks to safety and wellbeing for all family members. The Family Law DOORS (FL-DOORS; Detection of Overall Risk Screen) is a standardized screening framework to assist identification, evaluation, and response to family safety risks. The FL-DOORS has previously been validated in two large Australian samples (N = 6089) and found fit-for-purpose as an indicator of family violence and wellbeing risks in separated families. Now, using pilot data from a community mediation context, we examine its utility as a repeated measure for detecting change in safety and wellbeing over time. A pilot cohort of 67 parents engaged in a mediation service for parenting and/or property disputes completed the FL-DOORS at intake (T1) and approximately 8 weeks later (T2). We assessed T1-T2 change scores and correlations in change between variables and used MANOVA to determine if clusters of related scales discriminated change across time. Findings support the psychometric capacity of the FL-DOORS for use as a repeated measure in risk monitoring. We also note possible effects of this early screening process for reducing risk prior to engagement in mediation input. We discuss implementation utility for family law services to monitor change in risk type and magnitude over time.  相似文献   
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