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981.
A study was performed to acquire urine, serum and oral fluid samples in cases of suspected driving under the influence of drugs of abuse. Oral fluid was collected using a novel sampling/testing device (Dr?ger DrugTest System). The aim of the study was to evaluate oral fluid and urine as a predictor of blood samples positive for drugs and impairment symptoms. Analysis for cannabinoids, amphetamine and its derivatives, opiates and cocaine was performed in urine using the Mahsan Kombi/DOA4-test, in serum using immunoassay and gas chromatography-mass spectrometry (GC-MS) confirmation and in oral fluid by GC-MS. Police and medical officer observations of impairment symptoms were rated and evaluated using a threshold value for the classification of driving inability. Accuracy in correlating drug detection in oral fluid and serum were >90% for all substances and also >90% in urine and serum except for THC (71.0%). Of the cases with oral fluid positive for any drug 97.1% of corresponding serum samples were also positive for at least one drug; of drug-positive urine samples this were only 82.4%. In 119 of 146 cases, impairment symptoms above threshold were observed (81.5%). Of the cases with drugs detected in serum, 19.1% appeared not impaired which were the same with drug-positive oral fluid while more persons with drug-positive urine samples appeared uninfluenced (32.7%). The data demonstrate that oral fluid is superior to urine in correlating with serum analytical data and impairment symptoms of drivers under the influence of drugs of abuse. 相似文献
982.
The bodies of socially isolated people may remain undiscovered in their own houses for prolonged periods. Occasionally the body is in situ for sufficient time to become skeletonised, or partially so. Medico-legal investigation of these cases is complicated by degradation and contamination of evidence. Thus, a multidisciplinary forensic investigation is recommended. The potential contributions of forensic pathology, anthropology, odontology and entomology are outlined here with reference to two cases that occurred in Victoria, Australia, in 2003. Forensic pathologists are often unable to determine the cause of death in skeletonised bodies, however, they may find evidence to support either a natural or unnatural mode of death, and they may describe skeletal pathology or trauma, and identify skeletal features to support radiological identification of the deceased. Anthropologists can provide supplementary evidence of skeletal trauma. Additionally, they can assess age, sex, stature and racial affiliation from skeletal remains. Odontologists can identify individuals through comparison with ante-mortem dental records; however, potential difficulties exist in identifying the treating dentist of a socially isolated person. Odontologists may also examine the teeth and oro-facial skeleton for trauma. Entomologists may estimate minimum death time and/or season of death. Entomological examination of insect remains may also confirm that a body has lain in situ for a considerable period. 相似文献
983.
Eighteen external quality assessment (proficiency testing) samples were prepared from client specimens collected with the Intercept oral fluid collection device and by spiking drug-free oral fluid. Samples were circulated in pairs at quarterly intervals to 13 UK and USA based laboratories for analysis by a panel of OraSure micro-plate Intercept enzyme immunoassay kits and hyphenated mass spectrophotometric techniques. During the survey, there was a single case of non-specificity in a false report for methadone. The major errors were of lack of sensitivity relative to the concentration thresholds specified for the immunoassays. The sensitivity for overall "present"/"not found" reports calculated as true positives/(true positives+false negatives) were for the amphetamine specific assay 50%, methyl-amphetamines 93%, barbiturates 64%, cannabinoids 73%, cocaine and metabolites 100%, benzodiazepines 69%, methadone 95%, opiates 79% (opiates excluding oxycodone 93%), phencyclidine 93% and human gamma-globulin 97%. A small number of the sensitivity errors were attributable to errors in chromatographic confirmation techniques. 相似文献
984.
Salas A Prieto L Montesino M Albarrán C Arroyo E Paredes-Herrera MR Di Lonardo AM Doutremepuich C Fernández-Fernández I de la Vega AG Alves C López CM López-Soto M Lorente JA Picornell A Espinheira RM Hernández A Palacio AM Espinoza M Yunis JJ Pérez-Lezaun A Pestano JJ Carril JC Corach D Vide MC Alvarez-Iglesias V Pinheiro MF Whittle MR Brehm A Gómez J 《Forensic science international》2005,150(2-3):191-198
A qualitative and quantitative analytical method was developed and validated for the determination of 49 licit and illicit drugs in oral fluid. Small oral fluid samples, volume 1mL, were collected from volunteers using a modified Omni-Sal device and the analytes were extracted from an oral fluid/buffer mixture using a single Bond Elut Certify solid phase extraction cartridge. Liquid chromatography-tandem mass spectrometry (LC-MS-MS) and gas chromatography-repetitive full scan mass spectrometry (GC-MS) were used in parallel to analyze the extracts for the targeted drugs. Extracts were analyzed by GC-MS in their underivatized form and as their pentafluoropropionyl derivatives. Deuterated internal standards were used for quantification of drugs of abuse by LC-MS-MS to minimize matrix effects. Methadone-d(9) and tumoxetine were used as the internal standards for quantification of non-derivatized and derivatized analytes respectively by GC-MS. Linearity was demonstrated over the range 5-200 ng/mL and limits of detection were less than 4 ng/mL for each drug analyzed. The method demonstrated acceptable recoveries for most of the analytes and good intra- and inter-day precision. Acquisition of data by repetitive full scan GC-MS allows the addition of further analytes to the target menu. 相似文献
985.
Renita?R.?Glaser M.?Lee?Van.?Horn Michael?W.?ArthurEmail author J.?David.?Hawkins Richard?F.?Catalano 《Journal of Quantitative Criminology》2005,21(1):73-102
Prevention science has produced information about risk and protective factors that predict adolescent drug use and related problem behaviors. This paper investigates the Communities That Care Youth Survey that measures multiple risk and protective factors. Using a sample of 172,628 students who participated in surveys administered in seven states in 1998, analyses were conducted to test the factor structure of these risk and protective factors and to test the equivalence of the factor models across five racial/ethnic groups (African Americans, Asians or Pacific Islanders, Caucasians, Hispanic Americans, and Native Americans), four grade levels (6th, 8th, 10th, and 12th) and both gender groups. Results support the construct validity of the surveys risk and protective factor scales and indicate that the measures are equally reliable across males and females and five racial/ethnic groups. Implications of these findings for science-based prevention planning are discussed. 相似文献
986.
S R Sherman 《Social security bulletin》1985,48(7):27-43
Most new retired workers in 1982 owned some type of asset, usually a savings, checking, or credit union account, according to data obtained by the Social Security Administration (SSA) in its New Beneficiary Survey. Many recently retired workers also owned their home, often mortgage-free. Homeownership was their most significant asset in terms of its median value. Comparatively few retirees owned property other than a home, though for owners of such property, the median value was substantial. Married couples, whose assets included those of both partners, more frequently owned assets and their assets had higher median values than did unmarried individuals. A comparison of retired workers with persons aged 65 or older who were enrolled in the Medicare program but who had not yet received retired-worker benefits showed that these Medicare-only enrollees were much better off, both in the likelihood of owning assets and in having higher median values for their assets. Individuals who retired before reaching age 65 and therefore received a reduced social security benefit were not as well off as those whose first benefit was paid at age 65 or older. Overall, the asset situation of new retired workers in 1982 was better than that of men and unmarried women aged 58-63 in 1969, even when the 1969 assets were adjusted to constant 1982 dollars. 相似文献
987.
988.
989.
990.
This article is a nontechnical presentation of the debate that has gone on during the past decade over whether the U.S. social security system has depressed private saving in the economy. The heart of the article is an assessment of economist Martin Feldstein's original evidence, presentation of the alternative evidence that concluded that currently available historical data do not support the proposition that social security reduces private saving, and an evaluation of the contradictory evidence presented by Feldstein in response to the alternative evidence. The article concludes that, although the total body of evidence is inconclusive, the historical evidence fails to support the hypothesis that social security has reduced private saving. The Office of Research, Statistics, and International Policy, as part of its ongoing research mission, investigates the interrelationship between social security and the economy. This article presents an examination of one of several aspects of this relationship relevant to public policy considerations and is intended to make previously published technical papers available to a broader audience. 相似文献