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51.
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   
52.
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   
53.
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   
54.
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   
55.
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   
56.
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   
57.
This study is the first to examine the background level of male DNA on underpants worn by females in the absence of sexual contact. Here, we examined 103 samples from the inside front of underpants from 85 female volunteers. Samples were examined for the presence of male DNA using NGM SElect and PowerPlex Y23 kits. Only five samples gave a “complete” Y-STR profile, even though 83.5% of our volunteers cohabited with a male. In all cases where a partner reference sample was available, the Y-STR profile matched the cohabiting partner. We have demonstrated that a Y-STR profile is not expected on the inside front of underpants worn by females after social contact alone. The results of this study are informative for evaluating the significance of a Y-STR profile on underpants in cases of alleged sexual assault.  相似文献   
58.
Novel psychoactive substances (NPS) are synthetic drugs that pose serious public health and safety concerns. A multitude of NPS have been identified in the United States, often implicated in forensic investigations. The most common and effective manner for identifying NPS is by use of mass spectrometry and the true utility lies within nontargeted acquisition techniques. During this study, a liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) assay was developed, validated, and implemented for forensic toxicology testing. A SCIEX TripleTOF™ 5600 + with SWATH® acquisition was used. Resulting data were compared against an extensive library database containing more than 800 compounds. The LC-QTOF-MS assay was applied to the reanalysis of biological sample extracts to discover emergent NPS. More than 3,000 sample extracts were analyzed, and more than 20 emerging NPS were detected for the first time. Among these were isopropyl-U-47700, 3,4-methylenedioxy-U-47700, fluorofuranylfentanyl, N-methyl norfentanyl, 2F-deschloroketamine, 3,4-methylenedioxy-alpha-PHP, eutylone, and N-ethyl hexedrone.  相似文献   
59.
法益的体系性位置与功能   总被引:3,自引:0,他引:3       下载免费PDF全文
刘孝敏 《法学研究》2007,29(1):74-83
法益的体系性位置可以从法益与实定法的关系、讨论法益问题的领域两个角度来分析。在不同领域内讨论的法益,有不同的概念选择,发挥不同的功能。犯罪立法概念中的法益只能是宪法性法益,其功能在于为刑事立法者提供适当的刑事政策标准。犯罪司法概念中的法益,在入罪判断时只能是后刑法法益,可以指导解释刑法规定的行为构成;在出罪判断时只能是宪法性法益,通过法益价值的衡量,对符合行为构成的行为进行正当化处理。  相似文献   
60.
王方 《中国发展》2020,(1):45-50
产业结构的成长是每个发展阶段的国家都会遇到的问题。各种影响因素之间的博弈决定了产业结构成长的未来走向。该文基于系统科学的思想方法,认为产业结构的成长是多要素共同作用的过程,并且是一个快慢变量共同作用的过程,科技进步是产业结构系统中的快变量,而心智模式则是产业机构系统中的慢变量。通过对发达国家的产业结构成长的经验总结发现,以科技进步促进产业转型的同时,还要持续改进产业系统中的序参量,才能够持续推动中国产业结构的健康成长。  相似文献   
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