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821.
Cole J. Harvey 《欧亚研究》2020,72(5):837-862
Abstract Why are some elections manipulated more severely than others, and why do the techniques used to manipulate them vary over time and space? This article addresses these related questions by showing that patronage resources—not incumbent popularity—make manipulation appealing to frontline agents, while local political conditions can make manipulation personally risky for them. Agents can mitigate these risks by adopting more dispersed forms of manipulation like vote-buying, rather than more centralised falsification. These hypotheses are tested using forensic analysis of electoral data from more than 90,000 precincts per election across Russia’s 83 regions, from 2003 to 2012. 相似文献
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824.
When a bullet punctures a surface, it leaves behind a bullet impact, which can be analyzed in order to determine the origin and trajectory path from which a bullet was discharged using many different scientific methods to reconstruct a shooting scene. The purpose of the research was to test the accuracy and repeatability of reconstructing the impact angle of single bullet impacts using the ellipse method. The research was conducted by firing various calibers of ammunition into drywall panels positioned at varying angles of incidence from 88° until ricochet occurred. This was done in order to determine which caliber type and angle of incidence are most accurate and precise for reconstructing a shooting scene. The study examined four caliber types fired into drywall panels, with 5 repeated shots for each of the 11 angles of incidence (n = 220). Furthermore, 31 participants partook in the study to estimate a bullet impact angle of incidence utilizing the ellipse method. The results show that the best performance (accuracy and repeatability) is seen with the measurements of the 0.45 caliber ammunition. When angle of incidences is low (<64°), the performance (accuracy and repeatability) was seen to be better in all caliber ammunitions. Overall, the data provided for single bullet impacts deposited in drywall show that the ellipse method is useful in providing measurements for most crime scene reconstruction purposes and has also demonstrated that results vary depending on the type of ammunition, firearm, and angle of incidence being examined. 相似文献
825.
Dominic Gascho R.T. Mária Marosi R.T. Michael J. Thali M.D. Eva Deininger-Czermak M.D. 《Journal of forensic sciences》2020,65(4):1360-1364
Postmortem magnetic resonance imaging (MRI) is rarely used for the radiologic assessment of gunshot injuries, although it has clear advantages over postmortem computed tomography (CT) with regard to the imaging of soft tissue injuries. Another benefit in using MRI is that lodged projectiles composed of nonferromagnetic material such as lead present only marginal metal artifacts compared with severe artifacts on CT. This case report presents CT and MRI findings in a case with two gunshot wounds to the neck: a perforating wound and a nonperforating wound with a lead bullet lodged in the cervical spine. The decedent underwent CT and MRI before the scheduled autopsy. A ring of radiopaque material under the dermis in the fatty tissue was identified at both entrance wounds on CT, which was indicative of contact shots. The perforating gunshot was clearly indicated on CT by bullet fragments along the wound channel through the perforated 6th cervical vertebra and the fractured cricoid cartilage at the exit wound. The second trajectory, however, was only assumed based on the presence of gunshot residues at the entrance wound and the position of the lodged bullet. The radiologic assessment was severely impeded by the metal artifacts on CT. Barely noticeable metal artifacts on MRI allowed for clear visualization of the soft tissue injuries and the ruptured medulla oblongata. Only MRI clarified the soft tissue injuries of the brainstem noninvasively, which could provide specific and graphic information on the rapidity of death and the incapacitation of the victim. 相似文献
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827.
Owen Esaias M.Sc. Grant W. Noonan D.P.S. Shane Everist M.Sc. Michell Roberts B.B.Sc. Cassie Thompson M.Sc. Matt N. Krosch Ph.D. 《Journal of forensic sciences》2020,65(3):722-728
An important component of crime scene reconstruction is bloodstain pattern analysis (BPA). Where BPA concerns impact patterns, estimating the area of origin is critical information for scene reconstruction. Traditionally, this is achieved by measuring individual bloodstains and performing trigonometric calculations; however, 3D scanning has been proposed as a viable alternative for overcoming logistical and practical concerns with the manual method. Therefore, this project aimed to establish whether the FARO Focus 3D scanner and FARO Zone 3D software can improve the accuracy of area of origin estimates relative to the manual method. We created a series of eight bloodstain impact patterns and performed paired analysis using the two methods to estimate areas of origin for each pattern. Our data suggested that FARO-derived estimates were generally more accurate than using the manual method. FARO-estimated heights of origin areas were generally closer to the true distance. Both methods underestimated the distance from the wall for most patterns originating 150mm or greater from the wall, but overestimated distances for patterns originating closer to the wall. The degree to which distances were underestimated increased significantly the further the blood source was from the wall and was greater for FARO-derived estimates. The results of this research contribute to the validation of these instruments for operational implementation for BPA and should be considered alongside the practical benefits of 3D scanning relative to manual methods. Further, 3D scanning can provide reliable BPA reconstruction documentation for technical review and court presentation. 相似文献
828.
Adam Lanzarotta Ph.D. Martin M. Kimani Ph.D. Michael D. Thatcher B.S. John Lynch Ph.D. Moseley Fulcher A.S. Mark R. Witkowski Ph.D. JaCinta S. Batson M.S. 《Journal of forensic sciences》2020,65(4):1274-1279
This study describes the performance of handheld Raman devices for determining whether suspect pharmaceutical tablets declared to contain controlled substances were consistent with authentic (CWA) or not consistent with authentic (NCWA) tablets using a simple, rapid, field-friendly method capable of being used by nonexperts. Twenty-five authentic products and 84 known NCWA tablets were examined using three “parent” devices for a total of 327 analyses. On average, the parent devices yielded a true pass rate of 100%, a true fail rate of 98.4%, a false pass rate of 1.6%, and a false fail rate of 0%. The methods/libraries were then transferred to 13 identical “daughter” devices, which were used to examine 10 suspect finished dosage forms in duplicate (six known NCWA tablets and four authentic tablets) for a total of 260 measurements. On average, the daughter devices had a true pass rate of 100%, a true fail rate of 95.5%, a false pass rate of 4.5%, and a false fail rate of 0.0%. These data demonstrate that the parent–daughter electronic transfer method was successful, which permits the ability to develop methods in the laboratory that can be seamlessly pushed out to field devices. The methods can then be used to (i) prioritize samples for additional testing using other more time-consuming laboratory-based techniques needed to detect and quantify active ingredients and (ii) help support the interdiction of dangerous tablets at ports of entry, thereby preventing them from reaching the supply chain. 相似文献
829.
Sophia K. Chiu M.D. M.P.H. Jessica F. Li M.S.P.H. Kurt B. Nolte M.D. 《Journal of forensic sciences》2020,65(4):1324-1327
Recent increases in deaths in the United States from synthetic opioids such as fentanyl and fentanyl analogues (fentanyls) have raised concerns about possible occupational exposures to these potent agents. Medicolegal death investigators and autopsy suite staff might perform job tasks involving exposure to fentanyls. The potential for exposure to fentanyls among medicolegal death investigators and autopsy technicians at a state medical examiner's office was evaluated through review of caseload characteristics, injury and illness logs, and procedures and policies and discussions with management and employee representatives. The evaluation showed that this medical examiner's office had low potential for work-related exposure to fentanyls; its standard operating procedures and personal protective equipment requirements should reduce the potential for occupational exposure. Medicolegal death investigation agencies can develop and implement guidance to control exposures and provide workforce education and training to reduce the potential for work-related exposure to fentanyls. 相似文献
830.
Mamiko Fukuta M.D. Ph.D. Tetsuya Horita M.D. Yoshimi Seko-Nakamura B.S. Hideaki Kato M.D. Ph.D. Sanae Kanno Ph.D. Jun Monma-Otaki B.S. Yasuhiro Aoki M.D. Ph.D. 《Journal of forensic sciences》2020,65(3):1004-1008
A 55-year-old man complained of sudden onset of severe neck pain. This was followed by prompt loss of consciousness and death. Autopsy revealed rupture of a saccular aneurysm, which was considered to have resulted from enlargement of the remaining ductal tissue, and was located on the medial aspect of the uppermost portion of the descending aorta. Dense blood extravasation was noted in the posterior mediastinum and extending to the strap muscles of the neck and larynx. Histological examination of the rupture site revealed disappearance of the medial elastic fibers and thickened intima covered with dense fibrous tissue. Spontaneous ductus arteriosus aneurysm in adults is a rare finding, but widespread use of imaging technologies has revealed that it develops more frequently than previously recognized. Fatal complications may occur even when the aneurysm is relatively small. Therefore, pathologists should be aware of this aneurysm as a potential cause of sudden death. 相似文献