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41.
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
42.
Virginie Redouté Minzière M.Sc. Denis Werner M.Sc. Daniela Schneider M.Sc. Manuela Manganelli M.S. Balthasar Jung Ph.D. Céline Weyermann Ph.D. Anne-Laure Gassner Ph.D. 《Journal of forensic sciences》2020,65(4):1102-1113
Gunshot residue (GSR) analysis and their interpretation provide crucial information on a criminal investigation involving the use of firearms. To date, several approaches have been proposed for the implementation of a combined sampling and analysis of inorganic (IGSR) and organic GSR (OGSR). However, it is not clear at this stage if concurrent analyses of both types of residue might be detrimental to the analysis of IGSR currently applied in forensic laboratories. Thus, this work aims to compare and evaluate three different protocols for the combined collection and analysis of IGSR and OGSR. These methods, respectively, involve the use of a modified stub (with two halves, one for the detection of IGSR and the other for the analysis of OGSR); the sequential recovery of GSR with two stubs mounted with different adhesives (double-sided carbon tape and Tesa® TACK) and the sequential analysis of IGSR and OGSR from a single carbon stub following carbon deposition. The detection of IGSR was carried out using SEM-EDX, while OGSR analysis was performed using ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS). Obtained results for experiments performed using Geco Sinoxid® ammunition indicated that sequential analysis was the most suitable protocol for the combined collection and analysis of both IGSR and OGSR. A higher number of inorganic (characteristic and consistent) particles and higher concentrations of ethylcentralite, N-nitrosodiphenylamine, diphenylamine, and nitroglycerin were recovered with this method. 相似文献
43.
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
44.
Humanitarian organisations respond to increasing donor requests to assess economic aspects of their programmes, including cost-effectiveness. This article presents results from a survey of humanitarian agency staff and donor agencies, investigating such requests. Findings indicate a need for clear guidelines and capacity building in these economic assessments, expressed by both humanitarian staff and donor agencies themselves. While improving efficiency is important to ensure effective humanitarian response, caution is warranted in adopting overly burdensome and complex assessments of efficiency which are poorly understood by staff requesting and responding to them, the outcomes of which may lead to reductive and decontextualised decision-making. 相似文献
45.
AbstractScalability can be understood as the ability to expand without changing. Yet, expanding an intervention to a global scale, we suggest, is a significant and difficult accomplishment. In this paper we propose to explore the kind of evidential exigencies that this accomplishment involves. To do so, we focus on the field of global health and examine how child immunization against the pneumococcus bacterium has been scaled up in low-income countries. The paper first attends to initial epidemiological scrutiny that revealed the existence of a large-scale public health problem and the possibility of an expandable solution (vaccination). It then describes the set-up of a funding arrangement using overseas aid to purchase vaccine doses manufactured by pharmaceutical companies, before paying attention to various frictions that affect the widespread use of pneumococcal vaccines. In these different moments through which scalability is accomplished, always partially and temporarily, we show that a dual activity can be witnessed, a pivoting between referential work and forward projection. To conclude, we suggest that scalability is more usefully approached as a form of expansion that is always attentive to the possibilities of change. 相似文献
46.
Véra Ehrenstein 《Economy and Society》2018,47(1):162-186
AbstractThis paper explores an example of global politics in action by attending to the modalities and outcomes of United Nations negotiations on global warming. More precisely, the paper ethnographically traces how the capacity of tropical forests to act as carbon sinks is turned into a matter of global concern. The focus is on a negotiated policy called Reducing Emissions from Deforestation and forest Degradation (REDD+) and its anchoring in the Democratic Republic of the Congo, whose territory contains the second largest area of rainforest after Brazil. The paper discusses the importance of the promissory in climate actions, the multivalence of what is at stake and the porosity and resilience of national demarcation. To do so, it identifies three moments and sites of geopolitical re-composition: the formulation of international consensus, the work of preparatory agents and the quest for metrological inclusiveness. These moments and sites point to the theatricality and semi-secrecy of United Nations negotiations, the mobilizing activities of expatriate consultants hired with overseas aid funding and the unstable evidential grounds on which emission reduction efforts are based. The paper suggests that, through this series of processes, the carbon stored by tropical forests becomes a matter of global exigency. 相似文献
47.
48.
This paper deals with the long-term evolution of dock labor in Dakar. Through the utilization of archival sources and their analysis, this investigation explores the changes that occurred in this sector and primarily the reform plan developed during the world wars but that was never introduced into the labor regulations, mainly due to the colonial regime. In addition, this paper studies the legal changes since the 1970s when the dockers’ statute was settled. Furthermore, this research uses oral testimony from retired Senegalese dockers to study the way these workers observed these structural changes. It is the first time that this topic has been explored for the port of Dakar from a historical long-term perspective. 相似文献
49.
50.
Why do some peace agreements end armed conflicts whereas others do not? Previous studies have primarily focused on the relation between warring parties and the provisions included in peace agreements. Prominent mediators, however, have emphasised the importance of stakeholders at various levels for the outcome of peace agreements. To match the experience of these negotiators we apply a level-of-analysis approach to examine the contextual circumstances under which peace agreements are concluded. While prominent within the causes of war literature, level-of-analysis approaches are surprisingly scant in research about conflict resolution. This article compares two Sudanese Peace Agreements: the Comprehensive Peace Agreement (2005) that ended the North–South war and led to the independence of South Sudan, and the Darfur Peace Agreement (2006) which failed to end fighting in Darfur. We find that factors at the local, national and international level explain the different outcomes of the two agreements. Hence, the two case studies illustrate the merit of employing a level-of-analysis approach to study the outcome of peace agreements. The main contribution of this article is that it presents a new theoretical framework to understand why some peace agreements terminate armed conflict whereas others do not. 相似文献