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861.
862.
863.
Wilson JF Toseland PA Capps NE Sandle LN Smith BL Sweeney G Thomson AH Watson ID Williams J 《Forensic science international》2001,121(1-2):27-32
A mean of 44 members of the United Kingdom national external quality assessment scheme (UKNEQAS) for toxicology reported analytical findings on 10 toxicological cases circulated between December 1995 and February 2000. Material distributed usually consisted of a 5ml blood and a 20ml urine sample simulated by quantitative addition of drugs and their metabolites to material donated by volunteers and patients. The samples were accompanied by a brief outline of the circumstances surrounding the case. Laboratories were requested to report their analytical findings, list methods of analysis, and provide interpretation of their findings. The mean overall success rate for identification of drugs or their pharmacological group was 76%, failure being largely by laboratories providing an immunoassay-based screening service for a fixed range of drug groups. The latter laboratories indicated that cases would be referred to regional toxicology centres for further investigation or confirmation. The coefficient of variation of measurements was <7% for routine analytes, such as ethanol and paracetamol, but 26-44% for tricyclics and opiates. There were 3% false positive reports. The quantity and content of interpretative comment provided by the laboratories was very variable. A number provide nothing in addition to the analytical result. 相似文献
864.
Electrochemical interactions between latent human fingerprints and metal surfaces in ambient air are investigated using a scanning Kelvin microprobe. Inorganic salts present in sweat deposited at fingerprint ridges locally depassivate the metal surface producing a Volta potential decrease of greater than 200 mV. Volta potential patterns may persist for months and prints may be visualized by potential mapping, even when overcoated with a polymer layer. Because the Volta potential differences are produced by involatile salts they persist when the organic components of the fingerprint residue have been volatilized by heating to 600 degrees C. 相似文献
865.
Mass disasters represent a significant challenge for dental personnel who are frequently called upon to provide identifications. Recently-published materials have highlighted the need to prepare such groups for the disaster challenge and to report inadequacies in existing preparation methods with an emphasis on team integration, organization, and the psychological and emotional effects of such work. Many studies have retrospectively reported errors that have been made in disaster situations, but few have addressed the issues proactively. In an effort to provide a prepared team of dental members, a mock disaster exercise (Operation: DENT-ID) is conducted annually in Vancouver, Canada. The present study analyzes the effectiveness of this exercise in relation to team organization, assessment of preparedness, and the emotional and psychological issues. An index of preparedness is developed and described. This index, in the form of a questionnaire, can be given to participants in mock disasters to assess the effectiveness of such exercises. While the focus of this paper is on the assessment of dental personnel, the indices and methods used can be applied to any group working within the disaster team. Results indicate that the increase in preparedness as a result of the exercise was highly significant. 相似文献
866.
867.
868.
A study was undertaken to assess the stability and the radioimmunoassay (RIA) detection of cocaine, benzoylecgonine (BZE), and 11-nor-delta-9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in whole blood while stored in 4 different kinds of blood collection tubes for up to 30 days at refrigeration and room temperatures. At various intervals, the tubes were sampled and analyzed using Abuscreen RIA. Also, semi-quantitative data derived from RIA analysis of forensic blood specimens were compared with quantitative data acquired using gas chromatography (GC) or GC/mass spectrometry (GC/MS) on the same specimens. RIA and chromatographic studies revealed that BZE and THC-COOH were stable in blood under all conditions studied. Cocaine, however, was found not to be stable in blood, especially when stored at room temperatures. Despite cocaine's instability in blood, RIA was able to detect the presence of cocaine and its breakdown products in blood under all conditions studied. 相似文献
869.
870.
Most state constitutions contain detailed restrictions on thelegislative process. Violations of some of these restrictions(e.g., single-subject requirements) are reflected on the faceof a final enactment. Other violations (e.g., alteration ofa bill to change its original purpose) are not evident in thefinal enactment, but require investigation of the legislativeprocess. State courts have developed a variety of approachesto these second types of violations, from excluding all evidencebeyond the enactment to permitting any evidence of constitutionalviolations. The Pennsylvania Abortion Control Act was passedin apparent violation of both types of constitutional restrictions.The legislative debates reflected legislators' attitudes aboutsuch restrictions, but the Pennsylvania courts refuse to enforcethem. After surveying other judicial approaches, the articlediscusses the legislative and executive obligation to followconstitutional restrictions, regardless of judicial enforcement.The article then advocates increased judicial enforcement, whilemaintaining proper deference to the legislature. 相似文献