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351.
Cholesterol and squalene are fatty materials of latent fingermarks that can be utilized for dating methodologies and visualization techniques. Previous studies have suggested these compounds undergo degradation in fingermarks as a function of time (days) and light at ambient temperature. However, studies assessing how their composition changes at low and high temperatures over short periods of time (hours) have not been published previously. Here, we performed quantitative analysis of cholesterol and squalene in natural fingermark residue using PVDF membrane, after exposure to a range of temperatures (−20 to 100°C) for 4 and 8 h. We found that levels of both fatty materials remained constant at −20 to 60°C, but both showed significant reduction at 100°C, over short exposure times. These results indicate that cholesterol and squalene are detectable at −20 to 60°C, whereas at 100°C or higher, both are lost due to rapid thermal degradation.  相似文献   
352.
In the case of suspicious deaths, the technique of 1:1 taping is often used in Belgium. It consists of affixing a large number of adhesive tapes to the body of the victim. It is conventionally aimed at obtaining microtraces (e.g., fibers, hair) and is usually not used for DNA analysis. However, in some cases, DNA analysis of certain areas of interest identified on the 1:1 taping material can offer a last resort solution. The four-step method that is described in this article involves the selection of areas of interest on the body (Step 1), the selection of the corresponding tapes (Step 2), the decontamination of the tapes (Step 3), the selection of areas of interest on the tapes, for DNA sampling (Step 4). The method is illustrated by its successful application in four murder cases. In each case, DNA profiles of good quality could be identified, including profiles of persons different from the victim.  相似文献   
353.
The horizontal displacement of the human body resulting from fatal fall from a height is an important variable commonly used to inversely determine the cause or identify other forensic aspects of the fall. When examining the horizontal displacement, the wind effect is generally ignored. This technical note reports analytical modeling of the falling process, utilizing previous measurements of wind force acting on the human body, for determining the functional relationship between the wind speed and the horizontal displacement in the falling process. The result reveals that it does not take extremely rare wind conditions to cause a considerable shift of the human body, highlighting the importance to consider wind as a factor in investigations of fatal falls.  相似文献   
354.
Species identification of necrophagous insects found on a dead body is an essential key in applying medicolegal entomology to the estimation of postmortem interval (PMI). Due to limited morphological identification of insect evidence, several studies have identified species using molecular information such as DNA markers. While considerable cytochrome c oxidase subunit I (COI) gene sequence data of necrophagous fly species have been collected and annotated, those of necrophagous beetle species have not. Since necrophagous beetles such as Dermestes species have a larval period longer than that of flies, beetles are useful in even the late decomposition phase in estimating minimum PMI. To obtain the full-length COI gene sequences of six Dermestes species collected from South Korea, we designed primers for polymerase chain reaction amplification and sequencing. The obtained full COI nucleotide sequences were used for performing phylogenic analysis and comparison with previously reported sequences. The results demonstrated that the COI gene sequences could be used to identify forensically important Dermestes species in South Korea.  相似文献   
355.
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   
356.
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   
357.
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   
358.
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   
359.
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   
360.
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   
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