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排序方式: 共有5713条查询结果,搜索用时 15 毫秒
991.
Five 44 gallon drums labeled as glycidyl methacrylate were seized by the Australian Customs Service and the Australian Federal Police at Port Botany, Sydney, Australia, in December 2004. Each drum contained a white, semisolid substance that was initially suspected to be 3,4-methylenedioxymethylamphetamine (MDMA). Gas chromatography-mass spectroscopy (GC/MS) analysis demonstrated that the material was neither glycidyl methacrylate nor MDMA. Because intelligence sources employed by federal agents indicated that this material was in some way connected to MDMA production, suspicion fell on the various MDMA precursor chemicals. Using a number of techniques including proton nuclear magnetic resonance spectroscopy ((1)H NMR), carbon nuclear magnetic resonance spectroscopy ((13)C NMR), GC/MS, infrared spectroscopy, and total synthesis, the unknown substance was eventually identified as methyl 3-[3',4'(methylenedioxy)phenyl]-2-methyl glycidate. The substance was also subjected to a published hydrolysis and decarboxylation procedure and gave a high yield of the MDMA precursor chemical, 3,4-methylenedioxyphenyl-2-propanone, thereby establishing this material as a "precursor to a precursor."  相似文献   
992.
Methods to estimate adult age from observations of skeletal elements are not very accurate and motivate the development of better methods. In this article, we test recently published method based on the acetabulum and Bayesian inference, developed using Coimbra collection (Portugal). In this study, to evaluate its utility in other populations, this methodology was applied to 394 specimens from four different documented Western European collections. Four strategies of analysis to estimate age were outlined: (a) each series separately; (b) on Lisbon collection, taken as a reference Coimbra collection; (c) on Barcelona collection, taken as a reference both Portuguese collections; and (d) on London collection taken as reference the three Iberian collections combined. Results indicate that estimates are accurate (83-100%). As might be expected, the least accurate estimates were obtained when the most distant collection was used as a reference. Observations of the fused acetabulum can be used to make accurate estimates of age for adults of any age, with less accurate estimates when a more distant reference collection is used.  相似文献   
993.
Abstract:  We retrospectively reviewed autopsy records at a statewide medical examiner's office in order to identify and characterize deaths due to child abuse. In a 6-year period in New Mexico, the medical examiner investigated 45 deaths determined to be child abuse-related. Decedents were predominantly male (68.9%), Hispanic White (53.3%), and all were 5 years of age or younger, with a median age of 1 year. Head injuries were the most common cause of death (44.4%), followed by battered baby syndrome (15.6%). Relatives were involved as alleged perpetrators in 80% of the cases, with the father most often implicated (36.1% of cases), and 88.9% of child abuse injuries resulting in death occurred in the family's residence. Toxicology was positive in 26.7% of cases, but only two cases had substances of abuse present. Information on risk factors such as prematurity, parental age, and history of abuse was also collected.  相似文献   
994.
Abstract: This is a case report of a 30‐year‐old man found dead in his flat lying on the floor with multiple stab wounds over the body, surrounded by an extensive volume of blood. Examination of the scene of death showed a secure flat, locked from inside. A blood‐stained knife was present close to the body and two unstained notes left on the sofa at the locus. A small plastic bag containing white powder (which following toxicological examinations appeared to be cocaine) and an almost full bottle of beer were present on a table. Autopsy revealed more than 40 stab wounds to neck, chest, and abdomen arranged in isolated groups within which the wounds showed similar directions and had a transverse orientation. Together with hesitation marks located on the neck and wrists these characteristics allowed to interpret this case as a suicide.  相似文献   
995.
Abstract: The design and preliminary characterization of a novel sensor for drugs of abuse, DETECHIP®, is described in this proof‐of‐concept note. Combining both colorimetric and fluorimetric assays, DETECHIP® is suitable for lab and field use. More than a conventional spot test which provides a single “yes or no” answer, DETECHIP® provides twenty responses for a more complete characterization of suspect material. This is accomplished by visually noting colorimetric and fluorescent changes of carefully selected dyes upon the addition of test analytes, including drugs of abuse, with respect to controls. Color and fluorescence changes are recorded numerically so that a 20 digit identification code can be constructed for comparison of test analytes and known compounds. DETECHIP® is applicable to a variety of drugs, both plant‐derived and synthetic, addressing the need to use several different spot tests simultaneously for a single sample.  相似文献   
996.
Abstract: Three studies have proposed discriminant functions for sex determination from deciduous tooth crown dimensions, and this study tests the existing functions on a sample of 46 Portuguese immature skeletons of known sex, aged from birth to 10 years. Deciduous teeth were measured in their mesiodistal and faciolingual crown dimensions, and percentage of correct allocation accuracy in determining sex using each specific function was determined. Discriminant functions were also calculated from data collected for this study and tested using cross‐validation. Results show poor overall accuracy (33.3–75%) and poor cross‐validation (46.2–60.0%). This is related to low sexual dimorphism in deciduous tooth crown size, as well as differences in degree of sexual dimorphism and in overall tooth size between different samples. For these reasons, deciduous crown size does not seem to show significant forensic value as discriminator of sex, particularly when methods developed on one population are applied to individuals of another population.  相似文献   
997.
Parallel investment treaty arbitrations present a demonstrated risk of inconsistent awards. This article examines several ameliorative responses to parallel investment treaty proceedings, executable by treaty‐drafters, arbitrators and parties themselves. The unique jurisdiction mechanics and applicable law in investment treaty disputes frames the responses available. Despite the unique context within which parallel investment arbitrations occur, the challenges they pose to party interests, to principles including legal fairness and to the effective pursuit of dispute resolution closely resemble those posed by parallel proceedings in other domestic and international legal fora.  相似文献   
998.
Archaeological remains can provide concrete cases, making it possible to develop, refine or validate medico-legal techniques.In the case of the so-called ‘Joan of Arc's relics’ (a group of bone and archaeological remains known as the ‘Bottle of Chinon’), 14 specialists analysed the samples such as a cadaver X of carbonised aspect: forensic anthropologist, medical examiners, pathologists, geneticists, radiologist, biochemists, palynologists, zoologist and archaeologist. Materials, methods and results of this study are presented here.This study aims to offer an exploitable methodology for the modern medico-legal cases of small quantities of human bones of carbonised aspect.  相似文献   
999.
1000.
Although not common occurrences, schools are occasionally the site of barricaded captive events. To date little research has examined these acts of school violence. The purpose of this article is to describe 19 school barricaded captive events that occurred between February, 1998 and September, 2007 in the United States. Data were analyzed by examination of news reports of each incident, and include the following variables: Incident location (state, community), school level and size, time of day of the event, location of the event within the school, age and sex of the subjects, information about the captives, presence of school resource officers, student screening mechanisms, behavioral changes of the subjects, the subject’s expected outcomes, injuries or fatalities, demands and deadlines, captive escapes and releases, weapons, incident resolution, tactical team response, and negotiations. Results pertain to incident demographics, prevention/mitigation, and response.  相似文献   
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