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151.
Lawsone is a 2‐substituted‐1,4‐naphthoquinone derivative, which has been proposed as an alternative to the reagents currently used for fingermark detection on porous surfaces. 2‐substituted‐anthraquinones, which contain an additional conjugated benzene ring, have a similar chemical structure to that of lawsone. In this study, a new series of 2‐substituted‐1,4‐naphthoquinones and 2‐substituted‐1,4‐anthraquinones were synthesized and completely characterized by1H NMR,13C NMR, IR, and HPLC‐TOF/MS analyses. All newly synthesized 2‐substituted‐1,4‐quinones were investigated for their ability to develop latent fingermarks on porous surfaces, and this ability was compared with that of lawsone. Each fingermark developed was graded using an established method; thus, quantitative data were attributed to each fingermark. It has been demonstrated that the 1,4 ‐ quinones react with amino acids present in latent fingermarks on selected paper surfaces to produce faint yellow‐orange impressions, which exhibit strong photoluminescence when illuminated with a forensic light source at 440 nm and observed through a red filter. None of the compounds caused background darkening. The results obtained were generally similar to those of lawsone, however, 8‐dibromo‐2‐(propylamino)naphthalene‐1,4‐dione and 5,8‐dibromo‐2‐(propylthio)naphthalene‐1,4‐dione yielded better results for copier paper and colored (blue) copier paper used in this analysis. To the best of our knowledge, this is the first study to examine the role of 1,4‐anthraquinone derivatives as potential fingermark development reagents. The results indicate that 1,4‐quinones have a potential to be used as reagents for enhancement of latent fingermarks.  相似文献   
152.
153.
As digital evidence now features prominently in many criminal investigations, such large volumes of requests for the forensic examination of devices has led to well publicized backlogs and delays. In an effort to cope, triage policies are frequently implemented in order to reduce the number of digital devices which are seized unnecessarily. Often first responders are tasked with performing triage at scene in order to decide whether any identified devices should be seized and submitted for forensic examination. In some cases, this is done with the assistance of software which allows device content to be “previewed”; however, in some cases, a first responder will triage devices using their judgment and experience alone, absent of knowledge of the devices content, referred to as “decision‐based device triage” (DBDT). This work provides a discussion of the challenges first responders face when carrying out DBDT at scene. In response, the COLLECTORS ranking scale is proposed to help first responders carry out DBDT and to formalize this process in an effort to support quality control of this practice. The COLLECTORS ranking scale consists of 10 categories which first responders should rank a given device against. Each devices cumulative score should be queried against the defined “seizure thresholds” which offer support to first responders in assessing when to seize a device. To offer clarify, an example use‐case involving the COLLECTORS ranking scale is included, highlighting its application when faced with multiple digital devices at scene.  相似文献   
154.
Latent fingerprints were successfully visualized using fluorescence lifetime imaging (FLIM) on paper which emits strong fluorescence with a lifetime close to that of fingerprints and thus from which it is difficult for time-resolved spectroscopy to visualize fingerprints. Latent fingerprint samples on paper were excited using a 450 nm or 532 nm nanosecond pulsed-laser, and time-resolved fluorescence images were obtained at a delay time of 6–16 ns in intervals of 1 ns, to the excitation pulse. The excitation beam was expanded using a lens, and the fluorescence from the fingerprints was captured using an intensified CCD camera. Because of the large fluorescence intensity of the background paper of approximately two to four orders of magnitude larger than that of the fingerprint, the fingerprint was not visualized on each fluorescence image by time-resolved spectroscopy. However, the fingerprint was visualized in a FLIM image constructed using a series of the fluorescence images for the case with the fluorescence intensity of the background paper being four orders of magnitude larger than that of the fingerprint. The difference in fluorescence lifetime in the FLIM image of the visualized fingerprint and background paper was in the order of 0.1 ns, which was an order of magnitude smaller than the inherent fluorescence lifetime of a few nanoseconds for the fingerprints and paper. It was demonstrated that, at a background fluorescence intensity with a certain order of magnitude larger than that of fingerprints, FLIM has the potential to visualize latent fingerprints which cannot be visualized by time-resolved spectroscopy.  相似文献   
155.
The strategic behaviour of international oil companies in war-torn Sudan was overwhelmingly driven by political pressure from governments. After almost 20 years of operating in Sudan, the US giant Chevron was pushed to withdraw as a result of deteriorating relations between Washington and Khartoum. The Canadian flagship oil company, Talisman, which helped kick-start oil development after Chevron's exit also fell victim to Washington's ire. On the other hand, the European junior oil companies, Lundin and omv, protected by the European Union's political standpoint of ‘constructive engagement’ in Sudan, were free to profit. Finally, the eastern parastatals, led by a surging China, eager to capture international energy resources to fuel their budding economies and supported by the plural relationships fostered between their respective governments and the ruling, riverine elite in Khartoum, tactfully established a dominating presence. While fervent international human rights advocacy alone seemingly drove susceptible Western firms out of Sudan, the real power behind corporate movements came from the rules dictated by states.  相似文献   
156.
Over 30 years ago, Eric Browne and Mark Franklin demonstrated that parties in a coalition tend to receive portfolio payoffs in almost perfect proportionality to their seat share. Even though this result has been confirmed in several studies, few researchers have asked what the underlying mechanism is that explains why parties receive a proportional payoff. The aim of this paper is to investigate the causal mechanism linking party size and portfolio payoffs. To fulfil this aim, a small-n analysis is performed. By analysing the predictions from a statistical analysis of all post-war coalition governments in 14 Western European countries, two predicted cases are selected, the coalitions that formed after the 1976 Swedish election and the 1994 German election. In these case studies two hypotheses are evaluated: that the proportional distribution of ministerial posts is the result of a social norm, and that parties obtain payoffs according to their bargaining strength. The results give no support to the social norm hypothesis. Instead, it is suggested that proportionality serves as a bargaining convention for the actors involved, thus rendering proportional payoffs more likely.  相似文献   
157.
This article examines whether the career needs of legislators – to be re-elected or to move on to another political post – allow us to explain the rules governing committee structures and the committee assignments individual legislators obtain. It uses the institutional variations provided by Argentina, Costa Rica, and Venezuela to test hypotheses about committee assignments and committee assignment mechanisms. It finds that incentives created by candidate selection procedures and electoral rules show some relationship to committee assignments, but with a good deal of variation across national cases and individual careers.  相似文献   
158.
Since 2017, complaints of sexual violence have increased in France. At the same time, the management of sexual offenders has been at the center of international public health policies. The prevalence of mental disorders among sexual offenders is an essential field of research. There are some published studies on the prevalence of psychiatric disorders in sexual offenders in detention, but there are few recent published studies among French individuals who were detained. Our objectives were to determine the prevalence of psychiatric disorders among persons detained for sexual offenses and the level of care received according to their diagnosis. For this purpose, we carried out a retrospective observational study from January 2017 to October 2021 of all adult sexual offenders, whether accused or convicted, who were seen in the psychiatric consultation unit of Les Baumettes prison, Marseille, France. The primary outcome measure was the psychiatric diagnosis entered in the medical records. One hundred forty-two patients were included in analysis. All patients were men, and the majority (n = 97, 68.3%) of these patients presented with at least one psychiatric disorder, principally a personality disorder (31.7%). 10.6% presented with a schizophrenic disorder, 4.9% a bipolar disorder, 3.5% a depressive disorder, 5.6% pedophilic paraphilia, and 25.4% an addictive disorder. Their management and comorbid addictions were analyzed in subgroups for each psychiatric disorder. Patients appeared to receive an appropriate level of care for their diagnosed disorder. It seems important to develop structured assessment of recidivism risk for better management of sexual offenders.  相似文献   
159.
Establishing the path or trajectory of a fired bullet is an often recurring part of shooting incident reconstruction. The current study describes how gravitational pull causes a systemic error on the vertical component of a trajectory reconstruction. Bullet drop, drop angle, and vertical offset are explained and calculated for 10 different handgun/ammunition combinations over a range of distances up to 100 m. The presented results are intended to provide forensic firearm examiners with a reference frame for the magnitude of error introduced on handgun bullet trajectory reconstructions over distance. Threshold values of 20 and 30 m are proposed as conservative distances up to where bullet trajectories can be modeled as straight lines with subsonic/transonic handgun bullets and with supersonic handgun bullets respectively. Both the bullet drop and vertical offset will be below 5 cm at these distances for those categories. The drop angle will be below 0.3°.  相似文献   
160.
This research implements a fractographic approach to investigate the relationships between kinetic energy, firearm-to-target distance, and various aspects of fracture behavior in gunshot trauma. Gunshot experiments were performed on pig scapulae (n = 30) using three firearms generating different muzzle (initial) kinetic energies, including a 0.32 pistol (103 J), 0.40 pistol (492 J), and 0.308 rifle (2275 J). Specimens were shot from two distances: 10 cm (n = 15) and 110 cm (n = 15). Features evaluated in fractographic analysis such as cone cracks, radiating cracks, crack branching points, and circumferential cracks could be easily identified and measured in flat bones and allowed for statistical comparison of crack propagation behavior under different impact conditions. Higher-energy bullets produced more radiating cracks, more crack branching points, and longer fracture lengths than lower-energy bullets. Distance had no significant effect on fracture morphology at the distances tested. That quantitative measures of crack propagation varied with energy affirms that kinetic energy transfer is important in determining the nature and extent of fracture in gunshot wounds and suggests it may be possible to infer relatively high- versus relatively low-energy transfer using these features. Ranges obtained with the three firearms exhibited considerable overlap, however, indicating that other variables such as bullet caliber, mass, and construction influence the efficiency of energy transfer from bullet to bone. Therefore, fracture morphology cannot be used to identify a specific firearm or to directly reconstruct the muzzle (initial) kinetic energy in forensic cases.  相似文献   
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