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Fraudulent substitution of a page within a multiple page document such as a will or business contract, the counterfeit manufacture of paper banknotes, and linking ransom or extortion notes have all been the focus of criminal investigations at one time or another. In a recent homicide investigation, document examiners were requested to compare a threatening letter received by a business partner of the deceased with paper samples seized under warrant from a suspect's house. Through a quantitative elemental analysis of the concentrations of nine elements (Na, Mg, Al, Mn, Sr, Y, Ba, La, and Ce) within the questioned and specimen documents, determined by inductively coupled plasma-mass spectrometry (ICP-MS), it was concluded that (i) the paper of the threatening letter originated from a different source to that of the paper seized from the suspect's house and (ii) all six pages of paper seized from the suspect's house originated from the same source. This discrimination of paper is presented as both a statistical t-test analysis (99.9% confidence limit) as well as construction of an elemental fingerprint for individual replicates within the questioned and specimen sample populations. This is the first reported use of the comparison of the elemental composition of document paper, determined by ICP-MS, to assist in a criminal investigation.  相似文献   
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An unusual case of driving under the influence of the volatile anaesthetic enflurane is reported. A markedly affected anaesthetist was sniffing at an enflurane-moistened handkerchief before he crashed into a lorry at a red traffic light. In the blood sample enflurane (2.92 mg/l) as well as diclofenac (0.28 mg/l) and 4-aminophenazone (24.4 mg/l) were found. The way of driving and the accident and the deficiency symptoms could be explained by the central suppressing effects of enflurane. The physician was considered as impaired and not suitable to drive at the time of the incidence.  相似文献   
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Time-of-flight mass spectrometry (TOF-MS) offers new perspectives for forensic toxicology. Qualitative and quantitative analyses of a mixture of three selected benzodiazepines (diazepam, nordazepam and bromazepam) were used to compare gas chromatography (GC-TOF-MS, quadrupole GC-MS, GC-ECD) and liquid chromatography (HPLC-DAD) data. Method validation parameters like LOD, LOQ, S/N-ratios reflect the capabilities of GC-TOF-MS. Five-point calibrations for bromazepam in human peripheral blood (50, 100, 160, 200, 300 ng/ml) using medazepam as internal standard (1000 ng/ml) were performed. The calibrations using GC-TOF-MS (using the fragments of m/z 236 and 288), GC-ECD (dual system) and HPLC-DAD (at 235 nm) all showed correlation coefficients close or superior to 0.99. Quadrupole GC-MS data was not used in the comparison of extracted samples due to the low sensitivity in the full scan mode. Two analyses of real cases concerning bromazepam are presented. In the first case, the presence or absence of bromazepam could not be established with both HPLC-DAD and GC-ECD due to background signals. The extracted ion chromatograms and spectrum traces after the analysis with the GC-TOF-MS could clearly excluded the presence of bromazepam. The second case illustrates the quantitation of bromazepam, where both HPLC-DAD and GC-ECD were unable to give satisfactory results, again due to interfering background signals. The analyses performed on the GC-TOF-MS-system demonstrated high sensitivity and also high selectivity due to the high quality of mass spectra obtained. The advantages of GC-TOF-MS make it a promising analytical technique for forensic toxicology.  相似文献   
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This study examined the factors associated with resistance to peer pressure toward antisocial behaviors among a sample of Mexican-origin adolescents (n=564) living in a large Southwestern city in the U.S. A model examining the influence of generational status, emotional autonomy from parents, and self-esteem on resistance to peer pressure was tested independently for boys and girls. Gender differences emerged in the factors that influenced resistance to peer pressure. Results indicated that resistance to peer pressure was influenced by generational status and emotional autonomy from parents for both boys and girls. However, self-esteem was found to influence resistance to peer pressure only for boys.Mayra Y. Bámaca is a graduate student in Family and Human Development at Arizona State University. Her research interests include adolescent development among ethnically diverse populations, the influence of contextual factors in development, parenting adolescents, and resiliency among Latino adolescents and their families. This work was based on the master’s thesis of the first author.Adriana J. Uma?a-Taylor received her Ph.D. from the University of Missouri-Columbia and is currently an Assistant Professor of Family and Human Development at Arizona State University. Her research interests include ethnic identity formation during adolescence and resilience among Latino adolescents and their families.This study was supported, in part, by a grant to the second author from the Fahs Beck Fund for Research and Experimentation of the New York Community Trust.  相似文献   
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In this paper, the authors use the Bush administration's management grades from the Program Assessment Rating Tool (PART) to evaluate performance budgeting in the federal government—in particular, the role of merit and political considerations in formulating recommendations for 234 programs in the president's fiscal year 2004 budget. PART scores and political support were found to influence budget choices in expected ways, and the impact of management scores on budget decisions diminished as the political component was taken into account. The Bush administration's management scores were positively correlated with proposed budgets for programs housed in traditionally Democratic departments but not in other departments. The federal government's most ambitious effort to use performance budgeting to date shows both the promise and the problems of this endeavor.  相似文献   
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