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141.
Abstract: An LC–MS method was developed for benzylpiperazine (BZP) and trifluoromethylphenylpiperazine (TFMPP), constituents of “party pills” or “legal herbal highs,” and their metabolites in human blood plasma. Compounds were resolved using a mixture of ammonium formate (pH 4.5, 0.01 M) and acetonitrile (flow rate of 1.0 mL/min) with a C18 column. Calibration curves were linear from 1 to 50 ng/mL (R2 > 0.99); the lower limit of quantification (LLOQ) was 5 ng/mL; the accuracy was >90%; the intra‐ and interday relative standard deviations (R.S.D) were <5% and <10%, respectively. Human plasma concentrations of TFMPP were measured in blood samples taken from healthy adults (n = 6) over 24 h following a 60‐mg oral dose of TFMPP: these peaked at 24.10 ng/mL (±1.8 ng/mL) (Cmax) after 90 min (Tmax). Plasma concentrations of 1‐(3‐trifluoromethyl‐4‐hydroxyphenyl) piperazine peaked at 20.2 ng/mL (±4.6 ng/mL) after 90 min. TFMPP had two disposition phases (t½ = 2.04 h (±0.19 h) and 5.95 h (±1.63 h). Apparent clearance (Cl/F) was 384 L/h (±45 L/h).  相似文献   
142.
In this study, we randomly assigned 123 sixth and seventh grade classrooms from seven middle schools in the greater Cleveland area to one of two five-session curricula addressing gender violence/sexual harassment (GV/SH) or to a no-treatment control group. A baseline survey and two follow-up surveys were administered immediately after the treatment (Wave 2) and about six months post-treatment (Wave 3). In an earlier paper, we demonstrated the effectiveness of two approaches to youth GV/SH prevention programming (a fact-based, law and justice curriculum and an interaction-based curriculum). In this paper, we explored whether these largely positive findings remain for both girls and boys, including whether girls experience higher levels of GV/SH than boys. Most of our statistical models proved to be non-statistically significant. However, in 2 of our 48 victimization/perpetration (any violence, sexual violence and non-sexual violence) models (across two post-intervention follow-up points), we observed that the interventions reduced peer (male or female, non-dating partner) sexual violence victimization and reduced peer perpetration, but another outcome model indicated that the interventions increased dating perpetration. These mixed findings will need to be explored further in future research. Regarding our primary research question, we observed no statistically significant differences for the treatment multiplied by gender interaction terms for any of the perpetration or victimization outcome models, suggesting that the treatment had similar effects on girls and boys. However, we did observe that boys are more involved in violence than girls: both as victims and perpetrators. Boys experienced significantly more of three types of victimization from peers and dating partners compared to what girls experienced at the hands of their peers and dating partners. As perpetrators, boys committed more sexual victimization against peers (immediately post-intervention only) and more sexual victimization against dating partners than girls. The implications of these results are discussed.  相似文献   
143.
The diagnosis of posttraumatic stress disorder (PTSD) was introduced in 1980 with the publication of the Diagnostic and Statistical Manual of the American Psychiatric Association, Third Edition (DSM-III). DSM-III put forward a novel syndrome consisting of intrusive, avoidance/numbing, and arousal symptoms as distinctive psychopathology following exposure to traumatic events. The traumatic stressors, although expanded in later editions published in 1987 (DSM-III-R) and 1994 (DSM-IV), focus on life-threatening events and situations. However, at least 12 studies, most of them recent, have found associations between the PTSD symptoms and the PTSD symptom syndrome with stressors, such as unemployment and divorce that would not qualify, even in the broadened DSM-IV diagnosis, as traumatic stressors. These findings challenge the basic assumption on which the PTSD diagnosis is based, the assumption that exposure to life-threatening stressors is the primary cause of a unique set of stress response symptoms. The purpose of this paper is to show how to confront this challenge by developing a typology of stressful situations and events that can be tested systematically for their relation to the PTSD symptom syndrome and other relevant variables. The typology includes but is not limited to the types of situations and events defined as "traumatic" in the DSMs.  相似文献   
144.
Although sanction threats promote fear, among committed offenders, that fear can become a resource with which to sculpt emerging crime preferences. In such cases, criminality is not deterred but channeled. We explore the channeling process here as it relates to auto theft and carjacking. Our qualitative findings reveal that auto thieves are reluctant to embrace the violence of carjacking due to concerns over sanction threat severity they attributed to carjacking—both formal (higher sentences) and informal (victim resistance and retaliation). Meanwhile, the carjackers are reticent to enact auto theft because of the more uncertain and putatively greater risk of being surprised by victims, a fear that appears to overcome the enhanced long-term formal penalty of taking a vehicle by force. We examine the implications of offenders’ decision-making for the analytic intersection of rational choice and deterrence, offering the notion of projective risk sensitivity to encapsulate the process.  相似文献   
145.
The movements of political protest, competitive elections and the installation of new regimes are widely regarded as the most significant political upheaval to shake Africa since political independence. The impression is often given that this transformation has also seen the sweeping away of the old guard of autocratic leaders. The image of renewed leadership does not however correspond with reality. Taking the leaders that were in office in 1990 at the beginning of the democratisation movement, the article traces their subsequent history. It finds that half still hold the highest office, having for the most part successfully transformed themselves into 'democratic' leaders. This remarkable success story is examined, for the purpose of this article, from a voluntarist perspective, that is, the tactics that the incumbents pursued so as to remain in office are the focus. Continuing in the tradition of Sandbrook, and Jackson and Rosberg's work on 'personal rule',1 it constitutes a primer on how to hang on to power against the odds.  相似文献   
146.
Abstract

Despite its potential policy relevance, public opinion about homelessness has received little attention from researchers. This deficiency is addressed here by bringing together data obtained in four recent surveys. The survey results indicate that many Americans accurately perceive the characteristics of homeless people, consider homelessness a serious problem with structural roots, and support a variety of measures intended to solve it. Certain segments of the public— Democrats, liberals, blacks, and residents of communities that have homeless populations—are especially likely to hold these views. The extent to which the public's thoughts on homelessness have been shaped by the media is difficult to determine. However, an analysis of the volume and content of print and broadcast news coverage of the issue hints at a plausible causal connection.  相似文献   
147.
148.
While in recent years new charters and government actions have boosted the collective and individual rights enjoyed by “Fourth-World” indigenous peoples such as the Inuit, another set of indigenous peoples has not experienced such protection: “self-delimiting” peoples. Their rights go largely unprotected because of deliberate ambiguities in the word “indigenous”; because these peoples generally avoid all contact with the larger society, and so are unknown by it and have no voice in it; and because charters and institutions generally require validation of an indigenous people as bona fide—such as a history of contact and of evident land occupation—in order for the group to enjoy full rights protections. Both practice and theory may militate against the extension of full protection. This paper argues that theory, institutions building upon it, and practice realizable from theory and institutions must be reconsidered in terms of the particular circumstances and needs of these peoples if their rights are to be fully respected and maintained. Clear, special protection for these peoples’ rights to their culture must be established.  相似文献   
149.
150.
This review article argues that analyses of the food security implications of emerging powers in Africa could be strengthened through foregrounding the issue of perspective. Researchers working in this area should engage with food security opinion contests, and avoid obscuring these debates moving forward.  相似文献   
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