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271.
272.
In recent years, there has been a renewed interest in forensic sciences about forensic age estimation in living subjects by means of radiological methods. This research was conducted on digital thorax X-rays to test the usefulness of some radiological changes in the clavicle and first rib. The sample consisted in a total of 123 subjects of Spanish origin (61 men and 62 women; age range: 5-75 years). From all subjects, a thorax posterior-anterior radiograph was obtained in digital format. Scoring for fusion of medial epiphyses of the clavicle was carried out by Schmeling's system and ossification of the costal cartilage of the first rib by Michelson's system. Degree of ossification and epiphyseal fusion were analyzed in relation with known age and sex of these subjects. The results give a minimum age of >20 years for full fusion of the medial epiphysis of the clavicle (Stages 4 and 5). Concerning the first rib, all subjects with the final Stage 3 of ossification were above 25 years of age. These results suggest that the first rib ossification might become an additional method to the ones so far recommended for forensic age estimation in subjects around 21. New research would be desirable to confirm this suggestion. 相似文献
273.
During the analysis of "seized samples", suspected of containing 4-methylmethcathinone (mephedrone) and N-ethylcathinone (ethcathinone) additional compounds were observed in the GCMS chromatogram. These compounds were suspected to be the corresponding phenylacetone isomers of mephedrone and ethcathinone respectively. These isomers are referred to as iso-mephedrone and iso-ethcathinone, respectively. The identity of these compounds was verified by synthesising the isomers from known starting materials and comparing them with the compounds found in the seized samples. Analytical data, GCMS, NMR and IR on these compounds are provided. Possible explanations for the presence of these compounds in the seized samples are explored. Contaminated starting material is one suggestion. Rearrangement of the propiophenone based product to the phenylacetone based product is also suggested. The reaction of the α-bromopropiophenone with a primary amine can also lead to the phenylacetone based product. The presence of these isomeric compounds in seized samples could be used to compare different samples and attempt to establish a common origin. 相似文献
274.
Power JD McGlynn P Clarke K McDermott SD Kavanagh P O'Brien J 《Forensic science international》2011,212(1-3):6-12
The ring substituted methyl isomers of methcathinone, 2-, 3- and 4-methylmethcathinone were analysed. The 2- and 3-isomers were synthesized. The 4-methylmethcathinone isomer is also known as mephedrone and has been widely studied. We present GCMS, NMR and IR data for the three isomers. We show that the three isomers can be separated by GCMS and that the IR spectra for the three compounds can be used to distinguish between them. A seized sample was analysed and it was found to contain 4-methylmethcathinone and benzocaine. 相似文献
275.
Stability of raw TATP (3,3,6,6,9,9-hexamethyl-1,2,4,5,7,8-hexoxonane) samples in solutions of common solvents was studied to highlight problems faced by forensic labs in identification and analysis of organic peroxide samples. The TATP samples were prepared by reaction of acetone and hydrogen peroxide (30%) with the aid of following catalysts: hydrochloric, sulfuric, nitric, perchloric and methanesulfonic acid. Acetone, acetonitrile, methanol and acetonitrile/water solutions of TATP samples were prepared and stored at 50°C. Various degrees of stability were observed for particular combination of catalyst and solvent ranging from totally unstable (catalyst-H(2)SO(4)/any solvent) to very stable (catalyst-HCl/solvent acetonitrile). Purification of crude TATP by re-crystallization results in product stable in all investigated solvents. Stability of solution prepared from re-crystallized DADP (3,3,6,6-tetramethyl-1,2,4,5-tetroxane) was found to be on the same level as the stability of solution of re-crystallized TATP. 相似文献
276.
This article presents a thorough analysis of dual practice among physicians who work in both the public and private sectors. A conceptual framework is presented to help the reader understand dual practice and the contexts where it takes place. The article reviews the existing theoretical and empirical literature on this form of dual practice among physicians. It analyzes the extent of this phenomenon, the underlying factors that motivate physicians to engage in dual practice, and the main implications of their decision to do so. It also examines and discusses current policies that address dual practice. In this regard, the article provides some qualified support for the use of "rewarding" policies to retain physicians in the public sectors of more developed countries, while "limiting" policies are recommended for developing countries - with the caveat that the policies should be accompanied by the strengthening of institutional and contracting environments. The article highlights the lack of quality evaluative evidence regarding the consequences of dual practice on the delivery of health care services. It concludes that the overall impact of dual practice remains an open question that warrants more attention from researchers and policy makers alike. 相似文献
277.
Rocío Dánica Cóndor Antonino Scarelli Riccardo Valentini 《International Environmental Agreements: Politics, Law and Economics》2011,11(2):117-137
The three Rio Conventions—the United Nations Framework Convention on Climate Change, the Convention on Biological Diversity,
and the United Nations Convention to Combat Desertification—face the challenge to create synergies at different levels. The
objective of this article is to describe how we have assessed synergies between the Rio Conventions at the project level in
the forest sector. Since the complexity of the decision problem is high, we adopted the Multicriteria Decision Aid approach,
which can provide a broad insight into the decision problem and find a compromise solution to a problem with multidimensional
and conflicting criteria including social, economic and environmental features. The ELECTRE TRI model was used for assessing
synergies at the project level, and has been a useful tool to quantify the performance of afforestation and reforestation
projects into three categories (synergistic, reasonably synergistic, and not synergistic). For the first time, afforestation
and reforestation projects have been assessed in a comprehensive way through decision criteria that reflect global and local
interests using a non-compensatory multicriteria method. 相似文献
278.
Sandra L. Suárez 《Journal of Public Affairs (14723891)》2012,12(4):303-314
Because of popular and political pressure, governments have been compelled to regulate ‘excessive’ executive compensation and search both a policy and political solution. In this paper, I seek to establish the mechanisms of policy learning, competition, and emulation by examining American and British regulatory policies of executive compensation that show evidence of reciprocal diffusion, i.e. from the US to the UK and vice versa. The evidence suggests that during the past two decades, the extent of reciprocal policy diffusion varied and was primarily driven by policy learning. Using published government reports, press releases, public hearings, newspaper articles, and interviews, I demonstrate that reciprocal learning occurred because one country's policymakers and practitioners explicitly discussed and/or referred to the practices in the other country when deciding to adopt a specific policy solution to the problem of excessive executive pay. I discuss the implications for the literature on diffusion and point out avenues for future research. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
279.
Romão W Vaz BG Lalli PM Bueno MI Correa DN Telles VL de Castro EV Eberlin MN 《Journal of forensic sciences》2012,57(2):539-543
Using desorption/ionization techniques such as easy ambient sonic-spray ionization mass spectrometry (EASI-MS), it is possible to analyze documents of Brazilian vehicles for authenticity, providing a chemical profile directly from the surface of each document. A method for the detection of counterfeit documents is described, and the falsification procedure is elucidated. Forty authentic and counterfeit documents were analyzed by both positive and negative ion modes, EASI(±)-MS. EASI(+)-MS results identified the presence of (bis(2-ethylhexyl)phthalate plasticizer and of dihexadecyldimethylammonium biocide in both types of documents. For EASI(-)-MS results, the 4-octyloxybenzoic acid additive ([M + H](+): m/z 249) is present only in counterfeit documents. It was also found that counterfeit vehicle documents are produced via Laserjet printers. Desorption/ionization techniques, such as EASI-MS, offer therefore, an intelligent way to characterize the counterfeiting method. 相似文献
280.
Gómez-Valdés JA Quinto-Sánchez M Menéndez Garmendia A Veleminska J Sánchez-Mejorada G Bruzek J 《Forensic science international》2012,221(1-3):156.e1-156.e7
Sex estimation is the first step for biological profile reconstruction of an unknown skeleton (archaeological or contemporary) and consequently for positive identification of skeletal remains recovered from forensic settings. Several tools have been developed using different osseous structures. With the intention to provide an objective method comparison, we reported the analysis of three different methods (visual, metric and geometric morphometrics) for sex assessment of the greater sciatic notch. One hundred and thirty pelvic bones (45.4% females and 54.6% males) from the National Autonomous University of Mexico Skeletal Collection pertaining to the contemporary Mexican population were analyzed. We used the ROC-analysis to test between desired false positive thresholds (1-specificity) and expected true positive rates (sensitivity) in order to predict the best approach to sex assessment. The comparison of the area under the ROC-curves shows significant differences among visual and metric methods. At the same time, the analysis suggested that higher morphological variation among the sexes is independent of the methodological approach. The results indicate that the metric (angle), with a high percent of indeterminate cases (34.6%), and visual, with 26.2% of the cases allocated as intermediate cases, were poorly accurate; we cannot recommend these techniques for sexing an unknown specimen. On the other hand, the geometric morphometrics approach improves sex estimation in 82.3% of correctly classified individuals with more than 95% of posterior probability. In addition to the method comparison, the major sexual variation of the greater sciatic notch was determined to be located on its posterior border. 相似文献