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排序方式: 共有2647条查询结果,搜索用时 31 毫秒
931.
Greenspoon SA Yeung SH Johnson KR Chu WK Rhee HN McGuckian AB Crouse CA Chiesl TN Barron AE Scherer JR Ban JD Mathies RA 《Journal of forensic sciences》2008,53(4):828-837
Miniaturization of capillary electrophoresis onto a microchip for forensic short tandem repeat analysis is the initial step in the process of producing a fully integrated and automated analysis system. A prototype of the Berkeley microfabricated capillary array electrophoresis device was installed at the Virginia Department of Forensic Science for testing. Instrument performance was verified by PowerPlex 16 System profiling of single source, sensitivity series, mixture, and casework samples. Mock sexual assault samples were successfully analyzed using the PowerPlex Y System. Resolution was assessed using the TH01, CSF1PO, TPOX, and Amelogenin loci and demonstrated to be comparable with commercial systems along with the instrument precision. Successful replacement of the Hjerten capillary coating method with a dynamic coating polymer was performed. The accurate and rapid typing of forensic samples demonstrates the successful technology transfer of this device into a practitioner laboratory and its potential for advancing high-throughput forensic typing. 相似文献
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The current policy emphasis on data-driven decision-making is creating the right incentives for government agencies around the world that have not traditionally disseminated their administrative data to do so. The literature on statistical disclosure control focuses on the technical aspects of a variety of methods designed to protect data confidentiality. There is, however, a void in the literature in regard to what other elements are necessary to create and sustain a successful initiative. This paper examines six case studies of individual-level datasets. It reviews current practice in several domains and summarizes recommendations from expert practitioners including challenges for future initiatives. 相似文献
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Bailey J. Henwood B.Sc. Tracy S. Oost B.Sc. Scott I. Fairgrieve Ph.D. 《Journal of forensic sciences》2019,64(4):1139-1144
Studies on ballistic trauma to the ribs and thorax, cranium, and long bones demonstrate the potential of obtaining a bullet caliber from an entrance wound. In order to validate prior research on caliber estimation in bone tissue and assess the viability of bullet type determination based on the macroscopic evidence at the entrance wound, thirty fleshed pork (Sus scrofa) shoulders (humeri) were shot with either lead or copper jacketed bullets in one of three calibers; 0.22, 9 mm, or 0.38. Overall, our findings are consistent with previous research indicating that calibers can be grouped into “small” and “large” categories. Bullet type, lead or copper jacket, can be ascertained based on cortical flaking and the analysis of materials deposited around the entry wound. The addition of this evidence holds value in cases where no firearm or ballistic evidence is recovered from a crime scene. 相似文献
938.
A Hydrologic Retention System and Water Quality Monitoring Program for a Human Decomposition Research Facility: Concept and Design 下载免费PDF全文
Jeffrey R. Wozniak Ph.D. Monte L. Thies Ph.D. Joan A. Bytheway Ph.D. William I. Lutterschmidt Ph.D. 《Journal of forensic sciences》2015,60(1):54-60
Forensic taphonomy is an essential research field; however, the decomposition of human cadavers at forensic science facilities may lead to nutrient loading and the introduction of unique biological compounds to adjacent areas. The infrastructure of a water retention system may provide a mechanism for the biogeochemical processing and retention of nutrients and compounds, ensuring the control of runoff from forensic facilities. This work provides a proof of concept for a hydrologic retention system and an autonomous water quality monitoring program designed to mitigate runoff from The Southeast Texas Applied Forensic Science (STAFS) Facility. Water samples collected along a sample transect were analyzed for total phosphorous, total nitrogen, , , NH4, F?, and Cl?. Preliminary water quality analyses confirm the overall effectiveness of the water retention system. These results are discussed with relation to how this infrastructure can be expanded upon to monitor additional, more novel, byproducts of forensic science research facilities. 相似文献
939.
Samantha C. Robbins B.Sc. Scott I. Fairgrieve Ph.D. Tracy S. Oost B.Sc. 《Journal of forensic sciences》2015,60(Z1):S182-S187
This study examined the effects of fire on the features associated with saw marks in bone. Both class and individual characteristics were examined using stereomicroscopy and scanning electron microscopy (SEM). Twenty-four semifleshed Sus scrofa L. tibiae were sawed into three sections with the middle section having deep and shallow false starts. Twelve saw blades of varying age and type were each used to cut two tibiae. In each case, the first tibia was burned in an outdoor open fire to the point of partial calcination. The second tibia, our control, was macerated using a heated enzyme solution. Controls and burned specimens were examined for the following characteristics: breakaway spur, tooth hop, false start, exit chipping, tooth imprint, breakaway notch, pull out striae, kerf flare, and blade drift. In general, there was parity in the observed characteristics in the burned samples using the SEM and the stereomicroscope. SEM observation, however, provided enhanced images, with the addition of observing individual tooth imprints, previously not visible. Therefore, this study recommends using an SEM for the examination of saw cuts in burnt bone. 相似文献
940.
Analysis of the First- and Second-Generation Raving Dragon Novelty Bath Salts Containing Methylone and Pentedrone 下载免费PDF全文
Justin L. Poklis B.S. Carl E. Wolf Ph.D. Omar I. ElJordi M.S. Kai Liu Ph.D. Shijun Zhang Ph.D. Alphonse Poklis Ph.DT. 《Journal of forensic sciences》2015,60(Z1):S234-S240
In recent years, a large number of designer drugs sold as “Bath Salts” have appeared on the market. In July of 2011, Raving Dragon Novelty Bath Salts was obtained over the Internet. This product became unavailable in October of that year coinciding with the DEA issuing a temporarily schedule of mephedrone, methylone, and MDPV. Four months later in February of 2012, a new product was released from the same company under the new name Raving Dragon Voodoo Dust. The contents of both products were identified using spectroscopy methods: nuclear magnetic resonance, infrared, UV–visible, tandem mass spectrometry, and high-resolution time-of-flight mass spectrometry. It was determined that Raving Dragon Novelty Bath Salts contained methylone. The replacement product Raving Dragon Voodoo Dust contained the unscheduled drug pentedrone. The Raving Dragon brand of products illustrates the rapid change of ingredients in these products to circumvent laws restricting availability, distribution, and use. 相似文献