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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
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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
287.
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
288.
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
289.
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
290.
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