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941.
This study developed a composite machine learning algorithm for attribution of materials of forensic interest (like ammonium nitrate) to original sources. k-nearest neighbor and random forest models were used for source elimination and classification, respectively, in a two-step, composite algorithm based on particle color, size/shape, and trace element concentration features. Novel approaches for simulation to supplement within-source reference features based on empirically measured multi-lot analyses, an improved hold-one-lot-out method for cross-validation, an assessment of the likelihood of the presence of a reference sample, fusion of the source probabilities from the respective classification models, and the calculation of metrics for assessing ensemble sourcing performance are described. Excellent sourcing predictions were obtained; the sourcing algorithm identified the correct source as the top choice 89% of the time, and the correct source was identified to be an average of 2.7 times more likely than the most likely incorrect source. 相似文献
942.
Khizhnyak Sergey P. Zaraiskiy Alexander A. 《International Journal for the Semiotics of Law》2020,33(3):543-558
International Journal for the Semiotics of Law - Revue internationale de Sémiotique juridique - The article deals with the problem of coining terms and nomenclature signs with proper names... 相似文献
943.
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
944.
Andrea Y. Garzón-Serrano M.Sc. César A. Sierra Ph.D. Oscar Rodríguez-Bejarano Dr.Sc. Diana Sinuco Dr.Sc. 《Journal of forensic sciences》2020,65(4):1085-1093
Ammonium nitrate fuel oil is an explosive mixture found in most antipersonnel landmines (APL) buried throughout the Colombian territory. During more than 50 years of internal conflict, the Colombian government has found that trained dogs are the most effective method to detect APL. However, the olfactive signature in ANFO is unknown and also if there are differences in detection related to the explosive manufacturing origin. Therefore, this work begins with the analytical validation of the method used to determine ammonia, in its derivatized form as carbamate, released by home-made ANFO using HS-SPME-GC-FID. Once validated, the method was used to identify ammonia and other organic volatile compounds present in ANFO, under laboratory and simulated field conditions. The validation process includes the evaluation of the optimum conditions for the derivation and extraction of butylcarbamate, the determination of the working ranges with linear response in FID, the limits of detection and quantification, the sensitivity, and the precision. The results of the validation established linearity and sensitivity in a concentration between 20 and 120 mg/L, as well as low limits of detection and quantification of 6.4 and 21.4 mg/L, respectively. Also, an intermediate precision of 11% for butylcarbamate with a repeatability of 8%. The validated method showed in real samples of home-made ANFO besides ammonia, the presence of low molecular methylamines, and also exhibited differences in volatile compositions according to the origin. The objective of this work is to offer a reliable analytical methodology for the extraction and analysis of volatile compounds from ANFO. 相似文献
945.
946.
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
947.
Jeri D. Ropero-Miller Ph.D. Hope M. Smiley-McDonald Ph.D. Stephanie A. Zimmer Ph.D. Katherine M. Bollinger M.S. 《Journal of forensic sciences》2020,65(2):544-549
In 2007, the Bureau of Justice Statistics reported on 2004 data collected from the Census of Medical Examiner and Coroner Offices (CMEC). The CMEC was one of the first comprehensive reports on the state of the medicolegal death investigation system in the United States and included information on administration, expenditure, workload, specialized death investigations, records and evidence retention, and resources. However, the report did not include responses on questions that were related to toxicology such as specimen retention and type of testing. The purpose of this publication is to provide the community with toxicology laboratory-specific responses from nearly 2000 medical examiner and coroner (MEC) offices. Data obtained from a BJS CMEC public use dataset for any remaining information that was not reported in the 2007 BJS report were evaluated specific to the operation of toxicology laboratories within a MEC office or specific to toxicology testing. The CMEC includes information on average operating budget for MEC offices with internal or external toxicology services, budget for toxicology/microbiology services, respondents’ routine uses of toxicology analysis, toxicology specimen retention time, average turnaround times, use of computerized information management systems, and participation in federal data collections. These historical data begin to address the present state of our nation’s toxicology laboratories within the medicolegal death investigation system and their preparedness for the current drug overdose epidemic. 相似文献
948.
Netherlands International Law Review - Unlike the ICTY and ICTR Statutes, the Rome Statute of the ICC provides in Article 75 for various forms of court-ordered reparations for the victims of... 相似文献
949.
Research indicates that voters are not particularly effective at removing corrupt politicians from office, in part because voters make decisions on the basis of many competing factors. Party leaders are much more single-minded than voters and will choose to deselect implicated legislators if it means maintaining a positive party reputation and improving the odds of winning a legislative majority. We examine renominations to Italy’s legislature in two periods marked by corruption. We compare these renomination patterns with those from the prior legislature, when corruption lacked political salience. Our analysis shows that incumbent renominations are negatively associated with the number of press mentions that link the incumbent to corruption—but only when corruption is salient to the public. Our study highlights the importance of party leaders in forcing malfeasant legislators out of office—and reducing corruption—and redirects attention from voters to political elites as a critical channel in enforcing democratic accountability. 相似文献
950.
Richard A. Warshak 《Family Court Review》2020,58(2):432-455
Involvement in custody cases that include accusations of parental alienation—whether as an evaluator, expert witness, lawyer, judge, therapist, provider of a specialized intervention, or researcher—incurs both professional and personal risks. Some risks relate to false negative or false positive identifications of parental alienation that can lead to regulatory agency complaints and public condemnation by the parent who feels wronged by the case outcome. Other risks stem from providing services in an emerging area of practice and working with children who overtly oppose repairing the relationship with their rejected parent. These risks include: unfounded accusations of mistreating children; negatively biased commentary and sensationalist attacks in the media and in social media, professional conferences and journals, and in courtroom testimony; harassment, vilification, and invasion of privacy; threats of violence and public humiliation; shunning and rumor spreading by colleagues; and complaints to regulatory agencies. This article examines circumstances, beliefs, and dynamics that give rise to these risks, suggests precautions to reduce the risk of false accusations against professionals, and offers recommendations for dealing with regulatory agencies. Criticisms that a court or service provider has mistreated a child merit careful scrutiny in the context of the case evidence and empirical data. While some interventions for alienated children raise legitimate concerns, others have been maligned by anecdotal complaints that studies show do not represent the experience of most participants. 相似文献