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701.
702.
This paper describes the recovery and identification of crew members lost during a collision at sea. On 9 February 2001, south of Honolulu, Hawaii, the Japanese fishing training boat, Ehime Maru was struck by the USS Greeneville (SSN 772), a Los Angeles-class fast attack submarine. Witnesses estimate that the vessel sank within 5-10 min after the collision. Nine of the 35 crew members remained unaccounted for after rescue procedures were completed. The U.S. Navy attempted the unprecedented procedure of moving the boat from a depth of 610 m (2000 ft) into shallower waters so that the missing could be located and recovered. Eight of the nine crew members were recovered and identified by their dental records. 相似文献
703.
Agg KM Craddock AF Bos R Francis PS Lewis SW Barnett NW 《Journal of forensic sciences》2006,51(5):1080-1084
A rapid method for screening drug seizure samples for 3,6-diacetylmorphine (heroin), which consists of a simple hydrolysis procedure and flow-injection analysis with two chemiluminescence reagents, is described. Before hydrolysis, 3,6-diacetylmorphine evokes an intense response with a tris(2,2'-bipyridyl)ruthenium(III) reagent (prepared by dissolving the perchlorate salt in acetonitrile), and a relatively weak chemiluminescence response with a second reagent: potassium permanganate in an aqueous acidic polyphosphate solution. However, the permanganate reagent is extremely sensitive toward the hydrolysis products of 3,6-diacetylmorphine (i.e., 6-monoacetylmorphine and morphine). Some compounds commonly found in drug laboratories may cause false positives with tris(2,2'-bipyridyl)ruthenium(III), but do not produce the markedly increased response with the permanganate reagent after the hydrolysis procedure. The combination of these two tests therefore provides an effective presumptive test for the presence of 3,6-diacetylmorphine, which we have verified with 14 samples obtained from a forensic science laboratory. 相似文献
704.
Hypertension is a growing medical concern in the United States. With the number of Americans suffering from hypertension increasing, the use of antihypertensives such as beta-blockers is increasing as well. In fact, three beta-blockers - atenolol, metoprolol and propranolol - were among the 200 most prescribed medications in the United States in 2003. Pilots that successfully manage their hypertension can remain certified to fly. The Federal Aviation Administration currently designates approximately 8% of active pilots as "hypertensive with medication". The Civil Aerospace Medical Institute (CAMI) performs toxicological evaluation on victims of fatal aviation accidents. At CAMI beta-blockers are analyzed using gas chromatography with mass spectrometric detection. We have, however, recently developed a liquid chromatography with mass spectrometric detection (LC/MS) method for the simultaneous quantitation of three commonly prescribed beta-blockers, atenolol, metoprolol and propranolol. One advantage of our LC/MS method is the specificity provided by an ion trap MS. Utilizing an ion trap MS, we were able to conduct MS/MS and MS/MS/MS on each analyte. This method also eliminates the time-consuming and costly derivitization step necessary during GC/MS analysis. Additionally, by utilizing this novel method, any concerns about beta-blocker metabolite and/or sample matrix interference are eliminated. The limits of detection for this method ranged from 0.39 to 0.78 ng/mL and the linear dynamic range was generally 1.6-3200 ng/mL. The extraction efficiencies for each analyte ranged from 58% to 82%. This method was successfully applied to postmortem fluid and tissue specimens obtained from victims of three separate aviation accidents. 相似文献
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706.
This paper discusses changes in the social organization of mental institutionalization as they relate to developments in the wider social and economic environment. Despite dramatic changes in the system of inpatient psychiatric care during the last three decades, the historic division of labor between the private and the public system (with the latter treating the poor, the unemployed, and the nonwhite) has not ceased to exist. At the same time, under the influence of the postwar trend towards greater political integration of disadvantaged and marginal groups into society's central value systems, treatment of the mentally ill has become less segregated and more voluntary. An important implication of these two interacting trends--the changed legal position of the patient vis-à-vis the provider and the deteriorating economic position of the user of public psychiatric facilities--has been the exceeding irrelevance of one of the basic tenets of psychiatric care: that clinical treatment precedes social functioning. With two vignettes of chronic patients the article illustrates how symptoms and survival are fused in the contemporary, inclusionary system of care. 相似文献
707.
A basic median-voter model is developed and extended to analyze issues of economic regulation and public policy outcomes. The model is used to generate comparative static results relating changes in public-policy outcomes to changes in relative group sizes, total population, information costs, and population heterogeneity. The model is also used to explore the issue of optimal group size — the size of the special-interest group that maximizes the group's per capita public policy gains. Comparative static analysis reveals how optimal group size and gains per capita are affected by changes in population heterogeneity, the size of the total population, and relative knowledge levels. 相似文献
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