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41.
Specimens from fatal aviation accident victims are submitted to the FAA Civil Aerospace Medical Institute for toxicological analysis. During toxicological evaluations, ethanol analysis is performed on all cases. Care must be taken when interpreting a positive ethanol result due to the potential for postmortem ethanol formation. Several indicators of postmortem ethanol formation exist; however, none are completely reliable. The consumption of ethanol has been shown to alter the concentration of two major serotonin metabolites, 5-hydroxytryptophol (5-HTOL) and 5-hydroxyindole-3-acetic acid (5-HIAA). While the 5-HTOL/5-HIAA ratio is normally very low, previous studies using living subjects have demonstrated that the urinary 5-HTOL/5-HIAA ratio is significantly elevated for 11-19 h after acute ethanol ingestion. Recently, our laboratory developed and validated an analytical method for the simultaneous determination of both 5-HTOL and 5-HIAA in forensic urine samples using a simple liquid/liquid extraction and LC/MS/MS and LC/MS/MS/MS. In this previous work a 15 pmol/nmol serotonin metabolite ratio cutoff was established in postmortem urine, below which it could be conclusively determined that no recent antemortem ethanol consumption had occurred. In the current study this newly validated analytical method was applied to five ethanol-positive aviation fatalities where the origin of the ethanol present could not previously be conclusively determined. In four of the five cases examined the detected ethanol was demonstrated to be present due to postmortem microbial formation, and not consumption, even though some indication of ethanol consumption may have been present.  相似文献   
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A collaborative study on Raman spectroscopy was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on three dyed fibers: two red acrylics and one red wool. Raman instruments from six different manufacturers were tested as well as nine different laser wavelengths ranging from blue (lambda = 458 nm) to near infrared-NIR (lambda = 1064 nm). This represents the largest comparison study of Raman analytical parameters carried out on identical fiber samples. For the chosen fiber and dye samples, red lasers (lambda = 633 and 685 nm) gave the poorest spectral quality whereas blue (458 nm), green (514 nm) and near infrared lasers (785, 830 and 1064 nm) provided average results. Blue (488 nm) and green lasers (532 nm) globally gave the best quality spectra. Fluorescence problems were often encountered with some of the excitation wavelengths and therefore a flexible Raman instrument equipped with different lasers can be recommended to measure forensic fiber samples. The instrument should also be equipped with a Raman microscope in order to be able to focus on a single fiber. This study shows that Raman spectroscopy usually enables the identification of the main dye present in a colored fiber; however, minor dye components are much more difficult to detect. SERRS (Surface Enhanced Resonance Raman Scattering) techniques give an improvement of the dye's spectral intensity but no spectral improvement was observed for the two red acrylic and red wool fibers tested.  相似文献   
43.
Hypertrophic cardiomyopathy (HCM) is a disease process which results in a large, heavy heart, with hypertrophy of the interventricular septum (IVS) and left ventricle. HCM accounts for a significant number of cases of sudden cardiac death each year, most infamously in young athletes. The prevalence of the disease has increased over the past several years due to advances in clinical diagnosis and molecular genetic studies. Over this same period, new forms of treatment also have emerged. One such treatment is alcohol septal ablation (ASA). ASA is a procedure performed by a cardiologist, via cardiac catheterization, by injecting pure ethanol into selected arteries which supply the IVS, resulting in a targeted myocardial infarction. This infarct then retracts and forms a scar, decreasing the outflow obstruction and improving the patient's clinical symptoms.The authors report 2 cases of death following ASA treatment of HCM. The first, a 56-year-old male, had his ASA procedure 10 days prior to death. The second decedent, a 76-year-old female, had her procedure only 30 hours before death. These case reports are followed by a discussion about HCM, including pathology, treatments, and treatment-related pathology, before closing with a discussion about death certification in the cases presented and therapy-related deaths in general.  相似文献   
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American Grand Strategy in a World at Risk   总被引:1,自引:0,他引:1  
If there is no single long-standing American grand strategy, one nonetheless sees through the course of U.S. history the tracks of a grand strategy. It started with the idea of a U.S. monopoly in the Western Hemisphere, along with balances of power in the chief theaters of the world; with belief in the primacy of sea and air power and the need for an economic system to support these; and the objective of transforming international politics. Since 9/11, even if the strategic hierarchy, intensity, and political basis have changed, the Bush administration has largely been continuing in this same project, with a sensible strategy but poorly considered tactics.  相似文献   
46.
Administrators of law enforcement agencies are increasingly caught up in conflicts between demands to increase educational standards for police officers and the need to justify those increased standards based upon job relevance. On the one hand, national commissions suggest four year degree prerequisites for entry level into police work; on the other hand, police administrators are reluctant to impose rigid higher educational requirements because of possible negative ramifications such as a limited recruitment pool, rapid officer turnover, and court mandates to prove the job relevance of a college education. This study addresses these concerns by reviewing current empirical studies and relevant court decisions which add insight into this topic and which will, hopefully, assist administrators in making decisions regarding college educational requirements for hiring and promotion.  相似文献   
47.
Scholars have long understood that structuring internal work processes into more hierarchical or team‐based arrangements has consequences for organizational outputs. Building on this insight, this research examines the relationship between how agencies organize their rulemaking routines and the resulting rules. Tracking the job functions of rule contacts for economically significant rules proposed over a four‐year period, the analysis demonstrates that expanding the breadth of personnel types closely involved in a rulemaking is associated with a reduction in the time it takes to promulgate the rule. However, increasing the pace at which rules are finalized is not without cost, as those completed faster appear more likely to be overturned when challenged in court. The article not only adds another dimension to empirical scholarship studying rulemaking, which has largely focused on how forces originating outside the agency affect rules, but also suggests the importance of considering competing priorities in designing rulemaking processes.  相似文献   
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The article investigates the relationship between cultural similarities and differences on the part of the representatives of contending states and mediators, and outcomes of mediation efforts in militarized disputes. A distinction is made between social culture, defined primarily in terms of religious identity, and political culture, defined according to the state's political system. Analysis of 752 mediation attempts in militarized disputes occurring between 1945 and 1995 yields support for the hypothesis that mediation is more likely to succeed when the parties are from similar social cultures. The results, however, suggest that the relationship is more complex than that suggested by a simple categorization of states based on Huntington's "clash of civilizations" thesis. We also find that mediation is more likely to succeed when the parties share democratic political cultures, a finding that is consistent with the cultural/normative explanation for the democratic peace.  相似文献   
50.
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