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991.
Waltraud Baier M.Sc. Jason M. Warnett Ph.D. Mark Payne M.B.A. Mark A. Williams Ph.D. 《Journal of forensic sciences》2018,63(4):1298-1302
This case report presents one of the first reported uses of a 3D printed exhibit in an English homicide trial, in which two defendants were accused of beating their victim to death. The investigation of this crime included a micro‐CT scan of the victim's skull, which assisted the pathologist to determine the circumstances of the assault, in particular regarding the number of assault weapons and perpetrators. The scan showed two distinct injury shapes, suggesting the use of either two weapons or a single weapon with geometrically distinct surfaces. It subsequently served as the basis for a 3D print, which was shown in court in one of the first examples that 3D printed physical models have been introduced as evidence in a criminal trial in the United Kingdom. This paper presents the decision‐making process of whether to use 3D printed evidence or not. 相似文献
992.
Time Radically Alters Ex Situ Evidentiary Soil 16S Bacterial Profiles Produced Via Next‐Generation Sequencing,, 下载免费PDF全文
Alyssa J. Badgley M.S. Ellen M. Jesmok M.S. David R. Foran Ph.D. 《Journal of forensic sciences》2018,63(5):1356-1365
Previous research has revealed the potential of soil bacterial profiling for forensic purposes; however, investigators have not thoroughly examined fluctuations in microbial profiles from soil aged on evidence. In this research, soils collected from multiple habitats were placed on evidence items and sampled over time, and then bacterial profiles were generated via next‐generation sequencing of the 16S rRNA locus. Bacterial abundance charts and nonmetric multidimensional scaling plots provided visual representation of bacterial profiles temporally, while supervised classification was used to statistically associate evidence to a source. The ex situ evidence soils displayed specific, consistent taxonomic changes as they aged, resulting in their drift in multidimensional space, but never toward a different habitat. Ninety‐five percent of the 364 evidentiary profiles statistically classified to the correct habitat, with misclassification generally stemming from evidence type and increased age. Ultimately, understanding bacterial changes that occur temporally in ex situ soils should enhance their use in forensic investigations. 相似文献
993.
Quantification of Morphine,Codeine, and Thebaine in Home‐Brewed Poppy Seed Tea by LC‐MS/MS 下载免费PDF全文
Deborah Powers M.S. Stephen Erickson M.D. Madeleine J. Swortwood Ph.D. 《Journal of forensic sciences》2018,63(4):1229-1235
Recently, medical examiners reported two cases of a 21‐year‐old male and 24‐year‐old male with high amounts of morphine in their blood at autopsy. It was suspected that the decedents ingested lethal amounts of morphine from home‐brewed poppy seed tea. No studies to date have investigated opium alkaloid content extracted from poppy seeds by home‐brewing methods. Various poppy seed products were purchased from online sources and extracted with four home‐brewing methods representative of recipes found on drug user forums. Morphine, codeine, and thebaine were quantified in the tea extracts by liquid chromatography‐tandem mass spectrometry using a validated analytical method. Morphine, codeine, and thebaine concentrations from seeds were <1–2788 mg/kg, <1–247.6 mg/kg, and <1–124 mg/kg, respectively. Alkaloid yield varied between extractions, but regardless of extraction conditions, lethal amounts of morphine can be rinsed from poppy seed coats by home‐brewing methods. 相似文献
994.
Jatupon Krongvorakul M.D. Saranya Auparakkitanon Ph.D. Satariya Trakulsrichai M.D. Pitsucha Sanguanwit M.D. Jetjamnong Sueajai M.Sc. Nantida Noumjad B.Sc. Winai Wananukul M.D. 《Journal of forensic sciences》2018,63(4):1325-1330
Human xylazine poisoning is uncommon. This report describes the use of xylazine for intentional poisoning with criminal intent. Two incidents occurred within 3 weeks: the first involved one victim, and the second involved two victims. The clinical presentations were brief coma, bradycardia, hypotension, and hyperglycemia. The victims recalled having been given a drink from a stranger in a hospital waiting room before loss of consciousness. In the first case, general drug screening by gas chromatography/mass spectrometry (MS) revealed xylazine in the gastric contents, but liquid chromatography–tandem MS (LC‐MS/MS) of serum did not. In the second incident, LC‐MS/MS screening of both victims’ urine and serum samples revealed an unknown peak in the total ion chromatograms, which a molecular mass database identified as morantel or xylazine. The latter was confirmed by comparison with a xylazine standard. Based on this report, we suggest that xylazine should be classified as a controlled drug. 相似文献
995.
Teens and Spice: A Review of Adolescent Fatalities Associated with Synthetic Cannabinoid Use 下载免费PDF全文
Anthea B. Mahesan Paul M.D. M.Sc. Lary Simms D.O. M.Sc. Saeideh Amini B.Sc. M.Sc. Abraham Ebenezer Paul M.D. 《Journal of forensic sciences》2018,63(4):1321-1324
Synthetic cannabinoids (SCs) are commonly abused by adolescents with reported past year (2013) use in high school students between 3 and 10%. Standard adolescent postmortem toxicology does not include routine SC analysis, and thus, the true burden of fatalities related to SCs is unknown. A retrospective case review of two cases included scene investigation, interviews, autopsy, and toxicology. SCs were confirmed by liquid chromatography–tandem mass spectrometry (LC?MS/MS). Review of the eight adolescent SC‐associated fatalities in the literature revealed five of eight cases had no other discernible cause of death on autopsy. Compounds detected included PB‐22 (1.1 ng/mL), JWH‐210 (12 ng/mL), XLR‐11 (1.3 ng/mL), JWH‐122, AB‐CHMINACA (8.2 ng/mL), UR‐144 (12.3 ng/mL), and JWH‐022 (3 ng/mL). With synthetic drug use on the rise, forensic experts should have a high index of suspicion for the possibility of SC intoxication in adolescent fatalities with no other discernible cause of death. 相似文献
996.
Laser scanning technology is increasingly being used in forensic anthropological research to obtain virtual data for archival purposes and post hoc measurement collection. This research compared the measurement accuracy of two laser scanners—the FARO Focus3D 330X and the FARO Freestyle3D—against traditionally obtained (i.e., by hand) control data (N = 454). Skeletal data were collected to address a novel question: the ability of laser scanning technology to produce measurements useful for biological characteristic estimation, such as sex and stature. Results indicate that both devices produced measurements very similar to control (c. 3‐mm average absolute error), but also illuminate a tendency to under‐measure. Despite these findings, the virtual data produced sex and stature estimates that varied little from control‐produced estimates, signifying the usefulness of virtual data for preliminary biological identification when the skeletal elements are no longer available for physical analysis. 相似文献
997.
998.
受内在的诸多固有问题影响,传统涉农供应链无论采取总成本领先战略还是差异化战略都面临着重大障碍。21世纪农业高新技术的发展为涉农供应链提供了战略性再造的契机。它能够营造涉农链的高度稳定,进而强力支持涉农链基本竞争战略的实现和深化。 相似文献
999.
菲律宾是第一个表示支持美国反恐斗争的亚洲国家,反恐战争使双方之间的安全合作关系迅速升温,用美国总统布什的话说,美菲在反恐战争中已经是"军事同盟".本文分析了菲美安全合作关系迅速升温的原因、影响,并针对菲美安全合作对中国安全环境的影响提出了一些政策建议. 相似文献
1000.
温州汉族人群D7S2846、D19S400和D18S535基因座的遗传多态性研究 总被引:1,自引:0,他引:1
目的研究D7S2846、D19S400和D18S535位点在温州汉族人群的遗传多态性。方法EDTA抗凝血样采自194名无血缘关系温州地区汉族个体,用chelex-100法提取DNA,PCR扩增,聚丙烯酰胺凝胶电泳,银染显色分析。结果D7S2846观察到6个等位基因及15种基因型;D19S400观察到10个等位基因及36种基因型;D18S535观察到8个等位基因及26种基因型。各基因座的杂合度(H)分别为:0.644、0.724、0.772;个人识别能力(Dp):0.854、0.940、0.938。结论三个STR基因座具有较高杂合度,等位基因分布符合Hardy-Weinberg平衡,在法医学应用和群体遗传学研究中有较高的价值。 相似文献