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51.
X-ray photoelectron spectroscopy (XPS) is a widely used technique to characterize the surface chemistry of materials. It plays a crucial role in accessing qualitative and quantitative information and in detecting the presence of chemical functional groups on the surface of any material. The forensic methods available to detect and identify elements and organic/inorganic compounds are often destructive, so evidence cannot be re-analyzed. However, XPS allows rapid analysis of samples without damaging them. Recently, an increasing number of forensic researchers have begun to study certain chemical information on fingermarks. In this study, the authors aimed to present the applicability and power of XPS imaging in fingermark analysis which can also provide specific information about the fingermark chemical composition. Herein, monochromated X-ray (Al Kα) spot size was fixed at 50 μm. XPS mapping resulted in the acquisition of spectra at each pixel, in an array of 41 × 30 pixels with a step size of 50 μm. Then, a simple discussion has been made about how the scanned surface spectrum and basic snapshot spectra are used to identify different components at a fingertip of a scanned surface area (~3 mm2). Hence, a fingermark pattern contaminated with caffeine, TiO2, and Pb/PbO deposited on the silicon wafer can be chemically mapped and visualized by XPS using principal component analysis (PCA). Thus, the present study showed the possible applicability of XPS for the identification of illicit drugs of abuse, gunshot residue, and skin care products on latent fingermark by mimicking a crime scene evidence.  相似文献   
52.
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   
53.
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   
54.

The aim of this paper is to examine the influence of the right to information laws on sustainability transparency in European local governments. This goal is novel, in that previous studies have examined the effects of various factors on the dissemination of government information (demographic, socioeconomic, political and financial) but not the contribution of legal factors to online transparency on environmental, social and economic sustainability. Our research question is this: Do information laws contribute to transparency on sustainability? Using the Global Reporting Initiative guidelines and a statistical regression analysis, we studied the websites of 106 local governments in ten European countries. The results obtained show that when transparency laws clearly stipulate the rules applicable and the procedures established for appeals, exceptions, refusals and requests, this can favour transparency on environmental, social and economic sustainability. Our findings advance understanding of this field and reinforce the basis for legal reforms to enhance sustainability transparency.

  相似文献   
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56.
Persistent underperformance of public policy and program implementation in Aboriginal affairs is widely recognised. We analysed the results of two case studies of attempted reforms in public administration of Aboriginal primary health care in the Northern Territory, using a framework based on the institutionalist and systemic racism literatures, with the aim of better understanding the sources of implementation failure. Implementation of the agreed reforms was unsuccessful. Contributing factors were as follows: strong recognition of the need for change was not sustained; the seeds of change, present in the form of alternative practices, were not built on; there was a notable absence of sustained political/bureaucratic authorisation; and, interacting with all of these, systemic racism had important consequences and implications. Our framework was useful for making sense of the results. It is clear that reforms in Aboriginal affairs will require government authorities to engage with organisations and communities. We conclude that there are four requirements for improved implementation success: clear recognition of the need for change in ‘business as usual’; sustainable commitment and authorisation; the building of alternative structures and methods to enable effective power sharing (consistent with the requirements of parliamentary democracy); and addressing the impact of systemic racism on decision-making, relationships, and risk management.  相似文献   
57.
Housework and childcare have been considered mechanisms for ‘doing gender’ through the allocation of different functions to women and to men. Women continue to devote more time and effort to this type of work, in spite of their progressive incorporation into the labour market. Same-sex couples escape this gender binarism, and so this study set out to learn the distribution criteria work, as well as the influence of gender socialization when it comes to establishing this distribution. A qualitative investigation was carried out with 21 Spanish same-sex families. The results indicate that the majority of couples position themselves in an egalitarian discourse based on the absence of differentiated gender roles and a low level of specialization. No differences were found between male and female couples. Nevertheless, the female couples show higher levels of discontent when the distribution was not egalitarian. In conclusion, it is proposed that the effects of gender socialization are perpetuated beyond heterosexual relationships and also affect same-sex couples.  相似文献   
58.
This paper examines Irish campaigns for condom access in the early 1990s. Against the backdrop of the AIDS crisis, activists campaigned against a law which would not allow condoms to be sold from ordinary commercial spaces or vending machines, and restricted sale to young people. Advancing a conception of ‘transformative illegality’, we show that illegal action was fundamental to the eventual legalisation of commercial condom sale. However, rather than foregrounding illegal condom sale as a mode of spectacular direct action, we show that tactics of illegal sale in the 1990s built on 20 years of everyday illegal sale within the Irish family planning movement. Everyday illegal sale was a long-term world-making practice, which gradually transformed condoms’ legal meanings, eventually enabling new forms of provocative and irreverent protest. Condoms ‘became legal’ when the state recognised modes of condom sale, gradually built up over many years and publicised in direct action and in the courts.  相似文献   
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60.
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   
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