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231.
The increasing demand for rapid methods to identify both inorganic and organic gunshot residues (IGSR and OGSR) makes electrochemical methods, an attractive screening tool to modernize current practice. Our research group has previously demonstrated that electrochemical screening of GSR samples delivers a simple, inexpensive, and sensitive analytical solution that is capable of detecting IGSR and OGSR in less than 10 min per sample. In this study, we expand our previous work by increasing the number of GSR markers and applying machine learning classifiers to the interpretation of a larger population data set. Utilizing bare screen-printed carbon electrodes, the detection and resolution of seven markers (IGSR; lead, antimony, and copper, and OGSR; nitroglycerin, 2,4-dinitrotoluene, diphenylamine, and ethyl centralite) was achieved with limits of detection (LODs) below 1 µg/mL. A large population data set was obtained from 395 authentic shooter samples and 350 background samples. Various statistical methods and machine learning algorithms, including critical thresholds (CT), naïve Bayes (NB), logistic regression (LR), and neural networks (NN), were utilized to calculate the performance and error rates. Neural networks proved to be the best predictor when assessing the dichotomous question of detection of GSR on the hands of shooter versus nonshooter groups. Accuracies for the studied population were 81.8 % (CT), 88.1% (NB), 94.7% (LR), and 95.4% (NN), respectively. The ability to detect both IGSR and OGSR simultaneously provides a selective testing platform for gunshot residues that can provide a powerful field-testing technique and assist with decisions in case management.  相似文献   
232.
International non‐governmental organisations (INGOs) are prominent actors in the international arena, aiming to improve the life of disadvantaged people. However, INGOs often do not succeed in doing this. Consequently, INGO legitimacy is regularly questioned. Increased transparency and tightened accountability mechanisms are often‐mentioned solutions to this problem. Based on an analysis of four dimensions of INGO legitimacy—normative, regulatory, cognitive and output legitimacy—we argue that this is not necessarily adequate. We conclude that INGO mission statements create a normative source of legitimacy, but that this, in itself, is not enough to ground INGO legitimacy: it also needs to be institutionalised and organised. However, as a result of power relations and resulting pressures for accountability and transparency, as defined by their external stakeholders, INGOs experience a permanent struggle to reconcile their mission with the requirements for regulatory, cognitive and output legitimacy. The more these stakeholders press for increased organisation of INGO work, the more the pursuit of the core objectives of INGOs is obstructed. We illustrate this argument with the case of the post‐Tsunami humanitarian intervention (2004/2005). Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
233.
Current explanations of taxation levels have identified a host of factors, such as levels of economic development and GDP per capita, tax handles, tax morale, and political regimes. But none of them can account for Argentina's exceptionalism. Using a "transaction cost politics" approach and the case of Brazil for comparison, this article argues that the key to explaining low taxation in Argentina is political instability. Systemic instability affects the tax behavior of governments. Facing an uncertain future, incumbent governments choose to extract resources from society through inflation rather than normal taxation. This article argues that political institutions, particularly federalism, contribute to instability and thereby reduce the discount rates of government policymakers.  相似文献   
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Age at death assessment of adult skeletons is one of the most difficult problems in forensic and physical anthropology. Two fundamental sources of error are described: the complex variability in the process of skeletal aging and methodological bias. Taking into account these limits, we developed a new scoring system for the auricular surface of the ilium and the pubic symphysis. In order to address a large variability, we examine reference samples from Europe, North America, Africa, and Asia. Data were processed using Bayesian prediction in order to classify specimens in age range categories. Results show that combining indicators do not perform better than the auricular surface used as a single indicator. Morphological changes with aging are variable between Asian, African, and European populations, confirming the necessity to use population-specific standards. Bayesian prediction produces reliable classification and is applicable for subjects over 50 years old, a real methodological improvement.  相似文献   
238.
Age determination is a major field of interest in forensic anthropology. Among the different methods based on macroscopic skeletal study, the Suchey-Brooks method, which analyzes the pubic symphysis, is one of the most reliable. We applied the Suchey-Brooks method to three-dimensional computed tomographic reconstructions of the pubic symphysis. We demonstrated excellent agreement between the results of analysis of bone samples and those of the three-dimensional images, in particular regarding ridges of the articular surface and delimitation of the extremities. The accuracy of age estimation did not significantly differ (Wilcoxon test) between the Suchey-Brooks method applied to bones and the same method applied to CT images. Using high-quality images, this approach seems as reliable as the standard Suchey-Brooks method and offers several advantages: no bone preparation, no damage to bone material, and the possibility of application to living individuals.  相似文献   
239.
Allele frequencies of sixteen autossomal short tandem repeats (STRs), D3S1358, VWA, D16S539, D8S1179, D21S11, D18S51, TH01, FGA, D5S818, D13S317, D7S820, TPOX, CSF1PO, Penta D, Penta E (included in the PowerPlex 16 kit), and the SE33 (PowerPlex ES Monoplex System SE33) were determined in a sample of 200 healthy unrelated individuals from the north of Portugal.  相似文献   
240.
Analytical records concerning 440 living drivers suspected of driving under the influence of drug (DUID) were collected and examined during a 2 years period ranging from 2002 to 2003 in canton de Vaud, Valais, Jura and Fribourg (Switzerland). This study included 400 men (91%) and 40 women (9%). The average age of the drivers was 28+/-10 years (minimum 16 and maximum 81). One or more psychoactive drugs were found in 89% of blood samples. Half of cases (223 of 440, 50.7%) involved consumption of mixtures (from 2 to 6) of psychoactive drugs. The most commonly detected drugs in whole blood were cannabinoids (59%), ethanol (46%), benzodiazepines (13%), cocaine (13%), amphetamines (9%), opiates (9%) and methadone (7%). Among these 440 cases, 11-carboxy-THC (THCCOOH) was found in 59% (median 25 ng/ml (1-215 ng/ml)), Delta(9)-tetrahydrocannabinol (THC) in 53% (median 3 ng/ml (1-35 ng/ml)), ethanol in 46% (median 1.19 g/kg (0.14-2.95 g/kg)), benzoylecgonine in 13% (median 250 ng/ml (29-2430 ng/ml)), free morphine in 7% (median 10 ng/ml (1-111 ng/ml)), methadone in 7% (median 110 ng/ml (27-850 ng/ml)), 3,4-methylenedioxymethamphetamine (MDMA) in 6% (median 218 ng/ml (10-2480 ng/ml)), nordiazepam in 5% (median 305 ng/ml (30-1560 ng/ml)), free codeine in 5% (median 5 ng/ml (1-13 ng/ml)), midazolam in 5% (median 44 ng/ml (20-250 ng/ml)), cocaine in 5% (median 50 ng/ml (15-560 ng/ml)), amphetamine in 4% (median 54 ng/ml (10-183 ng/ml)), diazepam in 2% (median 200 ng/ml (80-630 ng/ml)) and oxazepam in 2% (median 230 ng/ml (165-3830 ng/ml)). Other drugs, such as lorazepam, zolpidem, mirtazapine, methaqualone, were found in less than 1% of the cases.  相似文献   
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