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921.
Munchelou M. Gomonit BS Britni Skillman PhD Madeleine J. Swortwood PhD 《Journal of forensic sciences》2024,69(2):678-687
There has been burgeoning interest in psilocybin-use for the treatment of various neurological and neurodegenerative diseases. Psilocybin is mistakenly perceived as the principal pharmacologically active compound due to its high concentrations found in magic mushrooms; however, it is the prodrug of psilocin. Despite the expanding body of clinical research seeking to understand the pharmacodynamic/pharmacokinetic properties of psilocin, and its role in inducing dramatic changes to cognitive function, there has not been a corresponding increase in the development of sensitive analytical methods that can quantify psilocin in different biological fluids. Existing analytical methods have been developed using plasma, serum, and urine as the matrix of choice, but with the unknown blood-to-plasma ratio of psilocin, any pharmacokinetic conclusions drawn solely on plasma data may be misleading. Thus, the main objective of this study is to develop the first analytical method that utilizes SPE and LC–MS/MS to quantify psilocin in human whole blood. The SPE procedure yielded a high recovery efficiency (≥89%) with minimal matrix effects. The method was validated according to ANSI/ASB 036 guidelines. Linearity was between 0.7–200 ng/mL and encompassed previously reported ranges found in plasma/serum. Bias, within- and between-run precision for all quality controls met ANSI/ASB 036 acceptability criteria. Endogenous/exogenous interferences and carryover were negligible. Psilocin stability was assessed at 4°C over 48 h and was considered stable. Although a proof-of-concept study will need to be performed to characterize the method, this analytical workflow was able to detect and quantify psilocin in human whole blood at low limits of quantification. 相似文献
922.
Nick Laan M.Sc. Rolf H. Bremmer Ph.D. Maurice C.G. Aalders Ph.D. Karla G. de Bruin Ph.D. 《Journal of forensic sciences》2014,59(1):34-41
The volume of bloodstains found on crime scenes may help forensic investigators reconstruct the location and kinematics of bloodletting events, as stain size, volume, and impact velocity are related. Optical coherence tomography was used as a method to determine the volume and volume ratio of dried and fresh bloodstains on both glass and irregular surfaces or deposited with an impact velocity. The volume of blood drops deposited on smooth glass surfaces was measured within a deviation of 2%. This deviation increased for droplets on irregular surfaces or deposited with an impact velocity. The volume ratio of dried and fresh bloodstains was equal to 19–28% depending on the individual donor and on the use of an anticoagulant. Optical coherence tomography is a good method to determine the volume of fresh and dried bloodstains in laboratory conditions and allows accurate determination of the dry/fresh ratio. 相似文献
923.
924.
ABSTRACT Social support from others with shared experiences can be an invaluable resource for individuals impacted by traumatic events, like school and mass shootings. While a growing body of literature explores the psychological impacts of these events on those who survive them, these studies predominantly focus on shootings at two universities, do not assess the effects beyond three years post-shooting, and rely almost exclusively on quantitative methodologies. To extend this body of literature, the present study relies on in-depth interviews with 16 survivors of the April 20, 1999 shooting at Columbine High School to explore the way in which they viewed various forms of social support during their trauma recovery process in both the short- and long-term. The findings indicate that the most effective support came from “similar others,” or those who had experienced the shooting in an analogous manner. Social support from the outside, even when well-intended, was viewed as unhelpful, while mixed perspectives were found related to community-level support. Based on these findings, broader consideration is given to the benefits of informal survivor networks. 相似文献
925.
固相微萃取(SPME)GC/MS、GC/MS/MS法检测环境水中的有机磷杀虫剂 总被引:11,自引:0,他引:11
目的 通过对固相微萃取 (SPME)条件的优化、筛选实验 ,建立环境水中有机磷杀虫剂的快速检验方法。方法 收集 17种有机磷杀虫剂 ,使用SPME并结合GC/MS、GC/MS/MS检验方法。结果 该方法简便、灵敏、迅速、可靠 ,样品利用率高 ,最低检测浓度为 0 .0 1~ 10 0 pg/ml,在痕量范围 0 .1~ 10ng/ml内线性回归好(相关系数r达 0 .99以上 )。结论 实际应用效果理想 ,有望成为公安、环保、检验检疫的农残及毒物分析中的一种快速有效的分析方法。 相似文献
926.
In this paper, we examine and compare the impact of social disorganization, including recent immigration, and other predictors on community counts of black and Latino motive‐specific homicides in Miami and San Diego. Homicides for 1985 to 1995 are disaggregated into escalation, intimate, robbery and drug‐related motives. Negative binomial regression models with corrections for spatial autocorrelation demonstrate that there are similarities and differences in effects of social disorganization and other predictors by motive‐specific outcomes, as well as for outcomes across ethnic groups within cities and within ethnic groups across cities. Recent immigration is negatively or not associated with most outcomes. Overall, the study shows the importance of disaggregating homicide data by race/ethnicity and motive and demonstrates that predictions based on existing theories are qualified on local conditions. 相似文献
927.
928.
儿童的参与权是确保儿童的各项权利能够真正得到实现的一项具有基本价值的权利。承认儿童的参与权也就意味着承认儿童是拥有权利的积极主体,承认儿童是儿童问题的专家。承认儿童的参与权也意味着对家长制作风的否定。中国儿童的参与权状况在近些年有了很大改善,但是,除非有系统的法律保障,儿童的参与权意识很难短时间内在大众的心里扎根,儿童也很难在影响他们自身利益的事务中发挥应有的作用。 相似文献
929.
930.
GC-PFPD法测定血中的杀虫双 总被引:3,自引:0,他引:3
杀虫双(dimehypo),化学名称为2-N,N-二甲基-1,3-双硫代磺酸钠基丙烷(C5H11NO6S4Na2)属于沙蚕毒素类杀虫剂。近年来对杀虫双的检验主要有GC/MS[1]、GC/TCD[2]等方法。用GC/PFPD进行检验的报道较少。通过对仪器条件和提取条件进行优化,建立了一种快速准确的分析方法。2004年11月11日,建德市某村黄某死于家中。为查明事实,建德市公安局送来死者心血要求毒物检验。运用建立的方法对死者的血液进行分析,在血液中检出杀虫双成份,谱图见图1。所以激发态硫分子(S*)的生成是至关重要的,而S*易形成于冷的富氢火焰[4]。通过设定检测器的温度… 相似文献