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61.
生产力是少数民族社会发展的最终决定力量;科学技术是第一生产力,是推动少数民族社会全面进步的伟大杠杆。我国少数民族社会必须通过科技建设与技术创新、民族教育的建设与创新、管理创新、民族文化的创新和发展,实现生产力的跨越式发展,促进少数民族经济社会的全面发展。 相似文献
62.
文章在对广西服务业发展现状、存在问题、面临的机遇与挑战等进行分析的基础上,系统探讨了广西服务业科技发展的战略选择、重大任务、重点领域、政策与保障措施等有关问题,对于促进广西服务业的进一步发展具有现实意义。 相似文献
63.
Wu-ting Tsai Ph.D. Chia-I Hu M.S. Chia-Yun Chang L.L.M. 《Journal of forensic sciences》2020,65(1):255-258
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
64.
Hari Jang M.S. Sang Eon Shin Ph.D. Kyu Jin Youm B.S. Mustafa Zafer Karagozlu Ph.D. Chang Bae Kim Ph.D. Kwang Soo Ko M.S. Seong Hwan Park M.D. Ph.D. 《Journal of forensic sciences》2020,65(1):283-287
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
65.
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
66.
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
67.
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
68.
Youngmin Kim M.S. Won-sil Choi Ph.D. Byoungjun Jeon B.S. Tae Hyun Choi M.D. Ph.D. 《Journal of forensic sciences》2020,65(2):458-464
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
69.
Sierra F. Kaszubinski B.Sc. Jennifer L. Pechal Ph.D. Carl J. Schmidt M.D. Heather R. Jordan Ph.D. Mark E. Benbow Ph.D. Mariah H. Meek Ph.D. 《Journal of forensic sciences》2020,65(2):513-525
Microbial communities have potential evidential utility for forensic applications. However, bioinformatic analysis of high-throughput sequencing data varies widely among laboratories. These differences can potentially affect microbial community composition and downstream analyses. To illustrate the importance of standardizing methodology, we compared analyses of postmortem microbiome samples using several bioinformatic pipelines, varying minimum library size or minimum number of sequences per sample, and sample size. Using the same input sequence data, we found that three open-source bioinformatic pipelines, MG-RAST, mothur, and QIIME2, had significant differences in relative abundance, alpha-diversity, and beta-diversity, despite the same input data. Increasing minimum library size and sample size increased the number of low-abundant and infrequent taxa detected. Our results show that bioinformatic pipeline and parameter choice affect results in important ways. Given the growing potential application of forensic microbiology to the criminal justice system, continued research on standardizing computational methodology will be important for downstream applications. 相似文献
70.
Kevin J. Farrugia Ph.D. Danielle Hunter B.Sc. Clarice Wilson B.Sc. Stef Hay B.Sc. Paul Sherriffs B.Sc. Paul Deacon B.Sc. 《Journal of forensic sciences》2020,65(1):248-254
This study presents a number of pseudo-operational trials on plastic bags investigating the double- and co-fuming process of a one-step fluorescent cyanoacrylate (LumicyanoTM) in comparisons with the two-step process with basic yellow 40 (BY40) staining for the detection of latent fingermarks. The results demonstrate that both Lumicyano solution and dye contribute to the increased detection of latent fingermarks during the double-fuming process (trial 1). Co-fuming the Lumicyano solution and dye separately (at a concentration of 8%) but simultaneously was less effective than 8% Lumicyano (trial 2). Co-fuming Lumicyano 8% and an additional 8% Lumicyano dye by weight was more effective than Lumicyano 8% (trial 3), possibly due to increased fluorescent material deposition during co-fuming allowing for better visualization. The use of BY40 after Lumicyano resulted in a considerable increase in detected fingermarks. 相似文献