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971.
Synthetic cannabinoids are sprayed onto plant material and smoked for their marijuana‐like effects. Clandestine manufacturers modify synthetic cannabinoid structures by creating closely related analogs. Forensic laboratories are tasked with detection of these analog compounds, but targeted analytical methods are often thwarted by the structural modifications. Here, direct analysis in real time coupled to accurate mass time‐of‐flight mass spectrometry (DART‐TOF‐MS) in combination with liquid chromatography quadruple time‐of‐flight mass spectrometry (LC‐QTOF‐MS) are presented as a screening and nontargeted confirmation method, respectively. Methanol extracts of herbal material were run using both methods. Spectral data from four different herbal products were evaluated by comparing fragmentation pattern, accurate mass and retention time to available reference standards. JWH‐018, JWH‐019, AM2201, JWH‐122, 5F‐AKB48, AKB48‐N‐(4‐pentenyl) analog, UR144, and XLR11 were identified in the products. Results demonstrate that DART‐TOF‐MS affords a useful approach for rapid screening of herbal products for the presence and identification of synthetic cannabinoids.  相似文献   
972.
This case report details an individual arrested for drug‐impaired driving after leaving the scene of multiple motor vehicle collisions and evading police. The driver was examined by a drug recognition expert and failed the drug recognition evaluation. The driver admitted to using cocaine, marijuana, an antidepressant medication and “N‐bomb,” a novel psychoactive substance that possesses hallucinogenic properties. Toxicological analyses at the Centre of Forensic Sciences’ Toronto laboratory revealed only the substance 2‐[4‐chloro‐2,5‐dimethoxyphenyl]‐N‐[(2‐methoxyphenyl)methyl]ethanamine (25C‐NBOMe) in the accused's urine. This is the first report in which 25C‐NBOMe was identified through DRE and toxicological analyses in a drug‐impaired driver.  相似文献   
973.
In forensic anthropology, age‐at‐death estimation typically requires the macroscopic assessment of the skeletal indicator and its association with a phase or score. High subjectivity and error are the recognized disadvantages of this approach, creating a need for alternative tools that enable the objective and mathematically robust assessment of true chronological age. We describe, here, three fully computational, quantitative shape analysis methods and a combinatory approach that make use of three‐dimensional laser scans of the pubic symphysis. We report a novel age‐related shape measure, focusing on the changes observed in the ventral margin curvature, and refine two former methods, whose measures capture the flatness of the symphyseal surface. We show how we can decrease age‐estimation error and improve prior results by combining these outline and surface measures in two multivariate regression models. The presented models produce objective age‐estimates that are comparable to current practices with root‐mean‐square‐errors between 13.7 and 16.5 years.  相似文献   
974.
This article describes how disrupting the activities of suspected violent extremists has become an increasingly significant construct in the policy and practice of the Prevent strand of UK Counter‐Terrorism. Informed by empirical data collected during semi‐structured interviews with police officers involved in conducting disruptions and members of the communities where these occurred, blended with a limited amount of field observation, the analysis documents how and why a logic of disruption has assumed increasing prominence in counter terrorism work. In respect of police interventions in particular, implementing disruptions, rather than pursuing fully‐fledged prosecutions, represents a pragmatic way of reconciling increasing demand with limited resources, as well as managing some of the difficulties of translating intelligence into legal evidence. Conceptualized in this way, the analysis positions disruption as a distinctive mode of crime prevention; one premised upon logics of near‐event interdiction. As such, it is understood as rather different in its operations and functions to other forms of “early intervention” that are increasingly prominent in much contemporary crime prevention policy. By focusing upon how specific Prevent interventions are implemented and performed this analysis makes a particular contribution to our knowledge of counter terrorism work. This reflects the fact that most previous studies of Prevent and other countering violent extremism programs have provided analyses of community perceptions and reactions to policing and the policy frame, rather than the configuration of the interventions themselves.  相似文献   
975.
Practicing recall of a non-target event prior to discussing substantive issues is a relatively new recommendation for interviews with child victims and witnesses. Despite evidence of the effectiveness of these practice narratives in obtaining detailed reports from children, specific recommendations about the duration and content of these interviews have yet to be systematically investigated. In the present study, 176 children aged 6–10 years watched a magic show and then participated in an interview that began with a practice narrative, with varying length (2 or 5 minutes) and topics (unique or commonplace), or no practice narrative. Conducting a practice narrative of any kind was beneficial to children's subsequent recall of accurate details over no practice narrative. Benefits to children's accurate recall were observed with as little as 2 minutes of practice and practice narratives were particularly beneficial if a unique, rather than commonplace, experience was targeted for practice recall. The present results confirm previous field research and laboratory findings indicating that the substantive phase of the interview is enhanced by conducting a practice narrative and extends the benefits of practice narratives to even a very brief practice narrative.  相似文献   
976.
For decades, America's state and local governments have promised their workers increasingly generous pensions but failed to fully fund them, producing a fiscal problem of staggering proportions. In this article, we examine the politics of public pensions. While mainstream theoretical ideas in the American politics literature would suggest the pension issue should be polarized, with Democrats pushing for generous pensions over Republican resistance, we develop an argument—rooted in more traditional theoretical work by Schattschneider, Lowi, Wilson, and others—implying that both parties should be expected to support generous pensions during normal times and that only after the onset of the Great Recession, which expanded the scope of conflict, should the parties begin to diverge. Using a new data set of state legislators' votes on hundreds of pension bills passed between 1999 and 2011, we carry out an empirical analysis that supports these expectations.  相似文献   
977.

Objectives

Criminologists have long studied the relationship between economic conditions and crime. Empirical evidence is inconclusive, pointing at different directions. This may reflect the conflicting theoretical predictions on the relationship between these phenomena, but also the prevailing methodological choice which focuses on linear relationships even though nonlinearities are plausible theoretically.

Methods

In this paper, we revisit the empirical relationship between economic conditions and crime by exploring potential nonlinearities. We look at flexible parametric specifications that include up to a cubic term of per capita income (or one dummy for each income quintile) and nonparametric and semi-parametric specifications (such as General Additive Models). Our results are robust to controlling for the standard socioeconomic, demographic, and policy determinants of crime, as well as to including a lagged dependent variable or state and time fixed effects.

Results

We document the existence of an inverted U-shaped relationship between crime and income within US states for the period 1970-2011. Crime increases with per capita income until it reaches a maximum, and then decreases as income keeps rising. This “Crime Kuznets Curve” (CKC) exists for property crime and for categories of violent crime that can be related to economic appropriation, like robbery, and is less robust for violent crimes not connected to economic incentives. We show that this pattern cannot be explained by correlated changes in economic inequality or by changes in law enforcement.

Conclusions

In addition to providing robust evidence of the existence of a CKC, our findings lay the groundwork for studies exploring the underlying theoretical mechanisms. These should go beyond income inequality or law enforcement, and should explain why the results hold more clearly for property than for violent crime. Our findings and subsequent research to understand the underlying drivers are relevant for policy, as they suggest that violent conflict cannot be tackled solely by the trickle-down forces of economic growth.
  相似文献   
978.
Several previous studies have found that interventions by security forces against criminal organisations result in increased violence related to organised crime. However, much less is known about how and why this effect occurs. Our study not only identifies the causal mechanisms that explain this outcome, but also evaluates the empirical validity of these mechanisms. Employing a novel data set, we find that following security-force intervention, the number of criminal organisations increases, and such greater fragmentation in turn raises the incidence of violence among criminal organisations as the relative power of the organisations changes. We employ a mediation model to verify the existence of these causal mechanisms. In addition, we find a decreasing rate of rise in levels of violence as the number of organisations increases.  相似文献   
979.
980.
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