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301.
Difference-in-difference methods are being increasingly used to analyze the impact of mergers on pricing and other market equilibrium outcomes. Using evidence from an exogenous merger between two retail gasoline companies in a specific market in Spain, this paper shows how concentration did not lead to a price increase. In fact, the conjectural variation model concludes that the existence of a collusive agreement before and after the merger accounts for this result, rather than the existence of efficient gains. This result may explain empirical evidence reported in the literature according to which mergers between firms do not have significant effects on prices.  相似文献   
302.
Stalking, which is a form of interpersonal violence, has been increasing and has a significant impact on affected victims. However, despite established scientific consensus, the juridical–legal system, specifically in Europe, is still extremely asymmetric. Portugal, compelled by scientific data and the Istanbul Convention, was the most recent country to approve specific legislation against stalking. In this critical review, we describe the previous national situation and provide examples from other countries to elucidate the trajectory of the recent criminalisation process, analyse the existing legal content and reflect upon the implications and challenges associated with this legal progression.  相似文献   
303.
One method that has been touted to help end mass incarceration is using intermediate sanctions. While intermediate sanctions often present as attractive options, there is evidence that as practiced, these sanctions often result in net widening. One of the most common forms of intermediate sanctions are drug courts, which are often viewed as progressive alternatives to locking up people with substance abuse problems. However, along with the dangers of net widening, scholars have shown that many people admitted to drug courts do not seem to have substance abuse problems and could benefit from lesser criminal justice interventions. In the current study, we analyzed intake data from a drug court to determine: (1) what charge(s) drug participants had and (2) how they became involved with the criminal justice system. Among important findings were that a large number of drug court participants were arrested for the possession of one drug only (often marijuana) and that more than half of participants came to the attention of the criminal justice system through a traffic stop rather than through repeated encounters with the criminal justice system.  相似文献   
304.
We report a case of fatal intoxication from 1,4‐butanediol (1,4‐BD), which was ingested by a young and “naïve” gamma‐hydroxybutyrate (GHB) consumer during a party with the co‐ingestion of alcohol, cannabis, and methylene‐dioxy‐methamphetamine. The following drug concentrations were found using gas chromatography coupled with mass spectrometry on autopsy samples and on a cup and a glass found at the scene: 20,350 mg/L (bottle) for 1,4‐BD; 1020 mg/L (femoral blood), 3380 mg/L (cardiac blood), 47,280 mg/L (gastric content), and 570 mg/L (vitreous humor) for GHB. The concentration of GHB is difficult to interpret in forensic cases due to the possibility of an endogenous production of GHB. The variable tolerance of the user may also modify the peri‐ and postmortem GHB concentrations. This case underscores the need to have many different sources of toxicology samples analyzed to avoid the hypothesis of endogenous production of GHB.  相似文献   
305.
Soil vestiges might provide information about a crime scene. The Rietveld method with X‐ray diffraction data (RM‐XRD) is a nondestructive technique that makes it possible to characterize minerals present in the soils. Soil clays from the metropolitan region of Curitiba (Brazil) were submitted to DCB treatment and analyzed using XRD with CuKα radiation in the step‐scan mode (0.02° 2θ/5 s). The GSAS+EXPGUI software was used for RM refinement. The RM‐XRD results, together with the principal component analysis (PCA) (52.6% total variance), showed the kaolinite predominance in most analyzed samples and the highest quartz contents in “site 1.” Higher anatase, and gibbsite and muscovite contents influenced discrimination, mainly in “site 3” and “site 1,” respectively. These results were enough to discriminate clays of four sites and two horizons using a reduced amount of sample showing that the technique can be applied to the investigation into soil vestiges.  相似文献   
306.
This article provides an in‐depth assessment of lone actor terrorists’ attack planning and preparation. A codebook of 198 variables related to different aspects of pre‐attack behavior is applied to a sample of 55 lone actor terrorists. Data were drawn from open‐source materials and complemented where possible with primary sources. Most lone actors are not highly lethal or surreptitious attackers. They are generally poor at maintaining operational security, leak their motivations and capabilities in numerous ways, and generally do so months and even years before an attack. Moreover, the “loneness” thought to define this type of terrorism is generally absent; most lone actors uphold social ties that are crucial to their adoption and maintenance of the motivation and capability to commit terrorist violence. The results offer concrete input for those working to detect and prevent this form of terrorism and argue for a re‐evaluation of the “lone actor” concept.  相似文献   
307.
An investigation into the effects of physical and chemical enhancement on subsequent presumptive and confirmatory tests for human blood is presented. Human blood was deposited onto porous (white 80 gsm paper and brown envelope) and non-porous (tile and linoleum) substrates in a depletion series (30 depletions on non-porous and 20 on porous) and subjected to three ageing periods; 1, 7 and 28?days. A number of enhancement techniques were tested [fluorescence, black magnetic powder (BMP), iron-oxide black powder suspension (PS), cyanoacrylate (CA) fuming, acid violet 17 (AV17), acid yellow 7 (AY7), ninhydrin, DFO and Bluestar Forensic Magnum (BFM) luminol] to evaluate their potential effects on subsequent presumptive and confirmatory tests. AV17 and Bluestar provided the best enhancement and fully enhanced all depletions in the series. The sensitivity of the Kastle-Meyer (KM) (presumptive), Takayama and RSID-Blood tests (confirmatory) was initially investigated to determine the range of detectable depletions. The KM test detected all depletions, whereas the Takayama test detected up to depletion 6 and RSID-Blood detected up to depletion 20 (paper), 10 (envelope), 15 (tile) and 9 (lino). The abilities of these tests to detect blood after enhancement were then observed.A number of techniques resulted in little to no effect on any of the blood tests, whereas adverse effects were observed for others. Ninhydrin and CA fuming caused weak but instantaneous positive KM results whereas methanol-based AV17 and AY7 delayed the reaction by as much as 1?min. The Takayama test was not very sensitive, therefore, its performance was easily affected by enhancement and negative results were often observed. RSID-Blood tests were largely unaffected by chemical enhancement although a drop in positive results was observed for some of the techniques when compared to positive controls.Using a standard procedure for DNA extraction, all the tested blood samples (before and after enhancement) gave a detectable quantity of DNA and were successfully profiled. Out of the 45 samples processed for DNA profiling, 41 gave full profiles, while the remaining showed allele drop out in one or two loci.  相似文献   
308.
It is important to understand the extent of transfer of explosive particles to different surfaces in order to better evaluate potential cross-contamination by explosives in crowded security controls such as those at airports. This work investigated the transfer of nine explosive residues (ANFO, dynamite, black powder, TNT, HMTD, PETN, NH4NO3, KNO3, NaClO3) through fingerprints from one surface to another. First, the extent of adhesion of explosive residues from different surfaces to the bare finger, nitrile and latex gloves was studied. Then, the transfer of explosive residues from one surface to another through fingerprints was investigated. Cotton fabric (hereinafter referred to as cotton) as clothing material and polycarbonate plastic (hereinafter referred to as polycarbonate) as luggage material were chosen for the experiments. These surfaces containing explosive particles were imaged using a reflex camera before and after the particles were transferred. Afterwards the images were processed in MATLAB where pixels corresponding to explosive residues were quantified. Results demonstrated that transfer of explosive residues frequently occurred with certain differences among materials. Generally, the amount of explosive particles adhered to the finger decreased in the following order: skin>latex>nitrile, while the transfer of particles from the finger to another surface was the opposite. The adhesion of explosive residues from polycarbonate to the finger was found to be better compared to cotton, while the amount of particles transferred to cotton was higher.  相似文献   
309.
In the context of increased scrutiny of the methods in forensic sciences, it is essential to ensure that the approaches used in forensic taphonomy to measure decomposition and estimate the postmortem interval are underpinned by robust evidence-based data. Digital photographs are an important source of documentation in forensic taphonomic investigations but the suitability of the current approaches for photographs, rather than real-time remains, is poorly studied which can undermine accurate forensic conclusions. The present study aimed to investigate the suitability of 2D colour digital photographs for evaluating decomposition of exposed human analogues (Sus scrofa domesticus) in a tropical savanna environment (Hawaii), using two published scoring methods; Megyesi et al., 2005 and Keough et al., 2017. It was found that there were significant differences between the real-time and photograph decomposition scores when the Megyesi et al. method was used. However, the Keough et al. method applied to photographs reflected real-time decomposition more closely and thus appears more suitable to evaluate pig decomposition from 2D photographs. The findings indicate that the type of scoring method used has a significant impact on the ability to accurately evaluate the decomposition of exposed pig carcasses from photographs. It was further identified that photographic taphonomic analysis can reach high inter-observer reproducibility. These novel findings are of significant importance for the forensic sciences as they highlight the potential for high quality photograph coverage to provide useful complementary information for the forensic taphonomic investigation. New recommendations to develop robust transparent approaches adapted to photographs in forensic taphonomy are suggested based on these findings.  相似文献   
310.
Forensic advisors (FA) at the National Institute for Criminalistics and Criminology (NICC), generalists in forensic science, act as an advising body to the magistrate to improve communication between the various parties involved in the investigation: magistrate, police and crime scene investigators, and forensic experts. Their role is manifold, but their main objectives are to optimise trace processing by selecting the most pertinent traces in the context of the case and by advising magistrates on the feasibility of forensic analyses in particular circumstances in regards to the latest technical advances.Despite the absence of a legal framework governing their role and involvement in judicial cases, the demand for their services has increased over the years. Initially, forensic advisors were called for complex homicide cases. Due to the proximity with the Public Prosecutor's Office, the types of offences for which their expertise was sought have become more diverse (mainly including robbery, burglary and sexual assault cases), leading to a diversity in the types of cases handled by the forensic advisors (complex, simple and review).In many of the cases they are requested for, in addition to consulting on the best analytical strategy, forensic advisors also assume the role of case coordinator regarding the seized objects and their respective analyses. Indeed, in the majority of cases treated by the FAs, two or more types of expertise have been requested and performed, either at the internal laboratories of NICC or at external laboratories.This paper explains the role of the forensic advisors in Belgium, the path that let to their current status and problems encountered.  相似文献   
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