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Andrea Y. Garzón-Serrano M.Sc. César A. Sierra Ph.D. Oscar Rodríguez-Bejarano Dr.Sc. Diana Sinuco Dr.Sc. 《Journal of forensic sciences》2020,65(4):1085-1093
Ammonium nitrate fuel oil is an explosive mixture found in most antipersonnel landmines (APL) buried throughout the Colombian territory. During more than 50 years of internal conflict, the Colombian government has found that trained dogs are the most effective method to detect APL. However, the olfactive signature in ANFO is unknown and also if there are differences in detection related to the explosive manufacturing origin. Therefore, this work begins with the analytical validation of the method used to determine ammonia, in its derivatized form as carbamate, released by home-made ANFO using HS-SPME-GC-FID. Once validated, the method was used to identify ammonia and other organic volatile compounds present in ANFO, under laboratory and simulated field conditions. The validation process includes the evaluation of the optimum conditions for the derivation and extraction of butylcarbamate, the determination of the working ranges with linear response in FID, the limits of detection and quantification, the sensitivity, and the precision. The results of the validation established linearity and sensitivity in a concentration between 20 and 120 mg/L, as well as low limits of detection and quantification of 6.4 and 21.4 mg/L, respectively. Also, an intermediate precision of 11% for butylcarbamate with a repeatability of 8%. The validated method showed in real samples of home-made ANFO besides ammonia, the presence of low molecular methylamines, and also exhibited differences in volatile compositions according to the origin. The objective of this work is to offer a reliable analytical methodology for the extraction and analysis of volatile compounds from ANFO. 相似文献
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Mária Kondeková Radoslav Beňuš Ph.D. Soňa Masnicová Ph.D. Petra Švábová Ph.D. 《Journal of forensic sciences》2020,65(4):1303-1309
Minutiae are small distinguishing features found along every ridge flow, which make each friction ridge print unique. The most common friction ridge prints found at the crime scene are fingerprints; therefore, the most of the minutiae studies are focused exactly on this kind of prints. The authors believe that further examination and enlargement of the palm print database could result in better use of the palm prints for personal identification. We analyzed a total of 160 palm prints from 40 females and 40 males aged between 18 and 70 years from Slovakia. For the evaluation of the minutiae, the area of the hypothenar had to be marked out. The classification of the minutiae used for this study was based on a modified version of the classification system using the total of 13 types of minutiae. The frequency of every minutiae type was calculated and, using the chi-square test with Yates's correction, bilateral and sex differences were assessed. The relationship between the different types of minutiae was examined with Pearson's correlation test. During the initial phases of the identification process, the focus should be on the least common types of minutiae (Y or M and return), which were found not to correlate; thus, their mutual occurrence is random (e.g., overlap—Y or M, crossbar—return, or Y or M—dock). The results of the present study show which specific minutiae types are the most suitable for personal identification. These findings may be beneficial in more effective outcome of the identification process. 相似文献
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Developing countries have suffered most of the financial crises in the context of the process of economic and financial globalisation. Both current and previous crises have revealed that unpredictability is a feature common to all the episodes which occurred during the process of globalisation. Although certain alarms went off, any of those external financial crises were actually predicted by the advanced methods in use for prediction and country risk analysis. Taking into consideration the information above, the aim of this paper is to check the ability to foresee external financial crises in developing countries of both the country risk index published by Euromoney and the Credit Ratings variable included therein. We have focused on the external financial crises that took place between 1992 and 2011, that is, in a full globalisation era. The results are negative. It appears that neither the index nor the sovereign ratings are able to reflect early enough the vulnerabilities that arise previously to the setting off the crisis episodes. This leads us to conclude that the existing models of country risk have limits. Thus, it would necessary to develop new instruments to measure this risk, considering uncertainty as an essential feature of the current economic and financial environment. 相似文献
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ABSTRACTSla?álek and Svobodová’s paper focuses on the ideology of the Czech Islamophobic movement as seen during the 2015–16 migration crisis. In their analysis of interviews with demonstrators and speeches by leaders of the movement, they discuss first how the movement imagined its enemies, and then describe its vision of positive core values. They conclude that the movement’s key ideological features are: an emphasis on social and civilizational decline (declinism); a return to an assumed naturalness in economic and gender relationships (naturalization); and the open evocation of violence and severity (brutalization). In terms of Rogers Brubacker’s distinction between xenophobic ethno-nationalism in Eastern Europe, and the xenophobic defence of liberal values in the West, Sla?álek and Svobodová find that the Czech case fits the allegedly western pattern better than the eastern one, which may cast doubt on the whole essentialization of distinctions between ‘western’ and ‘eastern’ populisms. 相似文献
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ABSTRACTGatti, Irazuzta and Martinez address the intercultural public policies implemented in the education system of the Autonomous Region of the Basque Country (Spain). Focusing on the education system allows them to reconstruct the historicity of identity-alterity production in a region in which language has been central for the establishment of ethnic frontiers. More specifically, they examine the implementation of these policies in three pre-school and primary educational institutions in a multicultural neighbourhood of the city of Bilbao. They look at Euskara—the Basque language—as a key element of the us-them distinction. The various education models regarding language and the teaching in/of Euskara or Spanish pave the way for the specialization and spatialization of the schools analysed. ‘Integration’ policies are implemented in ethnically marked schools only, based on a rhetoric of interculturality that assumes that any ‘racial or ethnic discrimination’ can be overcome through knowledge of the Other. Moreover, the assessment of public policies through ‘interculturality figures and best practice’ developed to address the so-called ‘immigration issue’ promotes a protectionist intervention on behalf of the assumed social vulnerabilities of immigrant schoolchildren and their families, which are read as ‘problematic characteristics’. The article argues that, as a result of the approach based on the social conditions of immigrant children and their families in the Basque Country, the race issue evaporates. 相似文献
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This paper asks whether strong bureaucracies can effectively constrain the continuously growing stock of rules in modern democracies through organizational coordination and learning. To answer this question, the paper analyzes the growth of rule stocks in the areas of environmental policy and social policy in 23 OECD countries over the period between 1976 and 2005. To do so, it develops a new measure of rule growth based on the content of laws and regulations rather than their length. The analysis highlights that effective bureaucracies are indeed better able to contain rule growth in these areas than weak bureaucracies. Since rules have to be implemented, countries suffering from bureaucratic capacity and quality constraints thus appear to be stuck in an implementation deficit trap. Appropriate implementation is not only inherently more challenging for countries with weak public administrations, but the body of rules to be implemented also tends to grow quicker in these countries. 相似文献