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961.
Terezie Cernosek B.S. Kevin E. Eckert M.Sc. David O. Carter Ph.D. Katelynn A. Perrault Ph.D. 《Journal of forensic sciences》2020,65(1):134-143
Volatile organic compounds (VOCs) are by-products of cadaveric decomposition and are responsible for the odor associated with decomposing remains. The direct link between VOC production and individual postmortem microbes has not been well characterized experimentally. The purpose of this study was to profile VOCs released from three postmortem bacterial isolates (Bacillus subtilis, Ignatzschineria indica, I. ureiclastica) using solid-phase microextraction arrow (SPME Arrow) and gas chromatography–mass spectrometry (GC-MS). Species were inoculated in headspace vials on Standard Nutrient Agar and monitored over 5 days at 24°C. Each species exhibited a different VOC profile that included common decomposition VOCs. VOCs exhibited upward or downward temporal trends over time. Ignatzschineria indica produced a large amount of dimethyldisulfide. Other compounds of interest included alcohols, aldehydes, aromatics, and ketones. This provides foundational data to link decomposition odor with specific postmortem microbes to improve understanding of underlying mechanisms for decomposition VOC production. 相似文献
962.
Asser H. Thomsen M.D. Hans Petter Hougen M.D. D.M.Sc. Palle Villesen Ph.D. Ole Brink M.D Ph.D. Peter M. Leth M.D. Ph.D. D.M.Sc. 《Journal of forensic sciences》2020,65(3):833-839
Sharp force trauma is a common homicide method. The weapon is typically a knife, which is easily accessible and does not require special skills. We have analyzed all 471 sharp force homicides in Denmark during 1992–2016 with special focus on aspects that are relevant to forensic pathologists, including the distribution of wounds and organ injuries. Most homicides were committed inside with a kitchen knife. The front left thorax was the most common area to be affected by sharp force trauma. In 18.9% of the victims, there was only one sharp injury, the majority on the thorax. The most common trajectory for stab wounds was directly posterior with no deviation to the sides or up/down followed by directly anterior. The heart (including pericardium) and lungs (including hemo- and pneumothorax) had injuries in more than 75% of the victims. 67% of victims were males. Female victims had more sharp force injuries and defense wounds than male victims. Most females were killed in domestic homicides (73.7%), most commonly in partner killings (56.4%). In contrast, many male victims were killed in a setting of nightlife/intoxication (34.0%) most by a friend/acquaintance delivering a few stab wounds. The results clearly show strong sex differences in both victims and offenders. This could be useful for shaping policies and public opinion, and as a route for understanding the developments in interpersonal violence. In the narrow setting of death investigation, our results will provide an evidence-based approach to understanding the injury patterns in sharp force homicide. 相似文献
963.
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
964.
Ju Yeon Jung M.S. Ga Hee Ryu B.S. Da-Hye Kim B.S. Joo-Young Kim Ph.D. In Kwan Hwang Ph.D. Pil-Won Kang Ph.D. Byung Won Chun Ph.D. Seong Yeon Yoo Ph.D. 《Journal of forensic sciences》2020,65(1):209-213
When using non-FTA cards in commercial multiplex STR kits for direct PCR, pretreatment steps with specific buffers are recommended. Here, we designed a rapid direct PCR method utilizing a non-FTA card, Oral Cell Sampling Kit, by omitting the pretreatment step involving Prep-n-Go™ Buffer, and it showed compatibility with the GlobalFiler™ Express PCR Amplification Kit, GlobalFiler™ PCR Amplification Kit, and PowerPlex® Fusion system. To optimize the PCR conditions, we tested the method with different final PCR volumes and cycles. Finally, we conducted a performance test using 50 Korean buccal samples and confirmed the high performance of the method, detecting more than 90% of the samples with full profiles when using GlobalFiler™ PCR Amplification Kit and PowerPlex® Fusion system at 29 cycles in a 10 μL final PCR volume. Thus, we report a simple direct PCR set-up to analyze reference samples collected using a non-FTA card manufactured in Korea. 相似文献
965.
Cristiane Barbosa D'Oliveira Matielo M.S. Rafael Plá Matielo Lemos Ph.D. Deise Schröder Sarzi M.S. Lilian de Oliveira Machado Ph.D. Dalvan Carlos Beise Bac. Priscila Caroline Thiago Dobbler M.S. Renata Machado Castro Bac. Mauro Sander Fett Ph.D. Luiz Fernando Würdig Roesch Ph.D. Flávio Anastácio de Oliveira Camargo Ph.D. Valdir Marcos Stefenon Ph.D. 《Journal of forensic sciences》2020,65(1):259-265
DNA is one of the fastest growing tools in forensic sciences, increasing reliability in forensic reports and judgments. The use of DNA has increased in different areas of the forensic sciences, such as investigation of plant species, where plastid DNA has been used to elucidate and generate evidence in cases of traceability of genetically modified and controlled plants. Even with several advances and the practice of using DNA in forensic investigations, there are just few studies related to the identification of genetic tools for the characterization of drug and nondrug-types of Cannabis. Herein, the whole plastomes of two drug-type Cannabis are presented and have their structures compared with other Cannabis plastomes deposited in the GenBank, focusing in the forensic use of plastome sequences. The plastomes of Cannabis sativa “Brazuka” and of the hybrid Cannabis AK Royal Automatic presented general structure that does not differs from the reported for other C. sativa cultivars. A phylogenomic analyses grouped C. sativa “Brazuka” with the nondrug C. sativa cultivars, while the hybrid Cannabis AK Royal Automatic placed isolated, basal to this group. This suggests that the analysis of plastomes is useful toward genetic identification of hybrids in relation to C. sativa. 相似文献
966.
Sizhe Huang Ph.D. Rongshuai Wang Ph.D. Bingbing Guo M.Bs. Hongbin Ruan M.Bs. Jinghong Ma M.M. Liang Ren Ph.D. Liang Liu Ph.D. 《Journal of forensic sciences》2020,65(3):1016-1022
Methyl nitrite is suggested to cause methemoglobinemia by generating methemoglobin, which may be lethal when the methemoglobin concentration exceeds 70%. However, intoxication with methyl nitrite is seldom reported compared with that with other nitrites. Here, we present an industrial accident involving methyl nitrite inhalation during its synthesis process that resulted in three fatalities and one survivor. The autopsy revealed conspicuous blue-gray discoloration in various parts of the body, including the skin, airway mucosa, vessels, brain, heart, and among other areas. The toxicological tests on the deceased showed methemoglobin concentrations in the blood over the lethal level and increased nitrite ion levels in the blood, gastric contents, liver, and lung tissue compared with those in control samples. The cause of death was determined to be methemoglobinemia-induced hypoxia due to methyl nitrite inhalation. This report provides evidence that in methyl nitrite intoxication, exposure duration has a significant influence on the postmortem changes and likelihood of a fatal outcome may be related to the age of the victim. More attention is required regarding the industrial hazards of this substance. 相似文献
967.
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
968.
Jong-Hyun Choi M.S. Jungheum Park Ph.D. Sangjin Lee Ph.D. 《Journal of forensic sciences》2020,65(3):966-973
Network-attached storage (NAS) is a system that uses a redundant array of disks (RAID) to create virtual disks comprising multiple disks and provide network services such as FTP, SSH, and WebDAV. Using these services, the NAS's virtual disks store data about individuals or groups, making them a critical analysis target for digital forensics. Well-known storage manufacturers like Seagate, Synology, and NETGEAR use Linux-based software RAID, and they usually support Berkeley RAID (e.g., RAID 0, 1, 5, 6, and 10) as well as self-developed hybrid RAID. Those manufacturers have published data on the introduction and features of hybrid RAID, but there is not enough information to reassemble RAID from a digital forensic perspective. Besides, digital forensic tools (such as EnCase, FTK, X-ways, and RAID Reconstructor) do not support automatic RAID reassembly for hybrid RAID, so research on hybrid RAID reassembly methods is necessary. This paper analyzes the disk array composed of hybrid RAID and explains the layout of disk array, partition layout in hybrid RAID, and hybrid RAID configuration strategy. Furthermore, it suggests parameters that are required for RAID reassembly and then propose a hybrid RAID reassembly procedure using them. Finally, we propose a proof-of-concept tool (Hybrid RAID Reconstructor) that identifies hybrid RAID from disk array and parse RAID parameters. 相似文献
969.
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
970.
Mitchell Messner M.D. Sarah E. Meyers M.D. Walter L. Kemp M.D. Ph.D. 《Journal of forensic sciences》2020,65(2):487-491
Previous studies suggest cardiovascular pathologists are less accurate than noncardiovascular pathologists (e.g., clinical pathologists) in estimating the degree of coronary artery stenosis. To further investigate the effect of training on accurate estimation of coronary artery stenosis, we designed a study to compare the accuracy of estimates made by forensic pathologists versus medical students. Six forensic pathologists and twelve medical students each independently examined 24 images of coronary artery cross sections and gave an estimate of the degree of stenosis. When comparing all 24 images, the forensic pathologists had a median difference between the estimated percentage of stenosis and actual percentage of stenosis of −12.380 and the medical students had a median difference of −16.50 (p-value of 0.08542). In estimating the percentage of stenosis, training in forensic pathology does not guarantee significantly improved accuracy compared with medical students. Our study showed no consistent statistically significant difference between estimates given by forensic pathologists and by medical students. 相似文献