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41.
This study developed a composite machine learning algorithm for attribution of materials of forensic interest (like ammonium nitrate) to original sources. k-nearest neighbor and random forest models were used for source elimination and classification, respectively, in a two-step, composite algorithm based on particle color, size/shape, and trace element concentration features. Novel approaches for simulation to supplement within-source reference features based on empirically measured multi-lot analyses, an improved hold-one-lot-out method for cross-validation, an assessment of the likelihood of the presence of a reference sample, fusion of the source probabilities from the respective classification models, and the calculation of metrics for assessing ensemble sourcing performance are described. Excellent sourcing predictions were obtained; the sourcing algorithm identified the correct source as the top choice 89% of the time, and the correct source was identified to be an average of 2.7 times more likely than the most likely incorrect source. 相似文献
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Minji Lee M.S. Ju Yeon Jung M.S. Sungsoo Choi M.S. Ilung Seol Ph.D. Seohyun Moon Ph.D. In Kwan Hwang Ph.D. 《Journal of forensic sciences》2020,65(6):2117-2120
Lophophora is a member of the Cactaceae family, which contains two species: Lophophora williamsii and L. diffusa. Lophophora williamsii is an illegal plant containing mescaline, a hallucinogenic alkaloid. In this study, a novel method based on a single nucleotide polymorphism (SNP) assay was developed for identifying L. williamsii; this assay reliably detects SNPs within chloroplast DNA (rbcL, matK, and trnL-trnF IGS) and was validated for identifying Lophophora and L. williamsii simultaneously. The chloroplast DNA sequences from four L. williamsii and three L. diffusa plants were obtained and compared using DNA sequence data from approximately 300 other Cactaceae species available in GenBank. From this sequence data, a total of seven SNPs were determined to be suitable for identifying L. williamsii. A multiplex assay was constructed using the ABI PRISM® SNaPshot™ Multiplex Kit (Applied Biosystems, Forster City, CA) to analyze species-specific SNPs. Using this multiplex assay, we clearly distinguished the Lophophora among 19 species in the Cactaceae family. Additionally, L. williamsii was distinguished from L. diffusa. These results suggest that the newly developed assay may help resolve crimes related to illegal distribution and use. This multiplex assay will be useful for the genetic identification of L. williamsii and can complement conventional methods of detecting mescaline. 相似文献
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Carla Guerrón Montero 《Bulletin of Latin American research》2020,39(2):191-207
This article analyses how a gendered perspective on community-based tourism (CBT) contributes to the realisation of identity and sovereignty of quilombos. It examines the potential sustainability of CBT coupled with agro-ecological practices within the context of gendered identity politics. Drawing from in-depth ethnographic and archival research conducted between February and July 2015 at Campinho da Independência (Rio de Janeiro, Brazil), the article discusses how female leaders integrate sustainable agro-ecological practices and CBT with environmental education in what they call ‘ethno-ecological tourism’. This approach to CBT strengthens a proudly defiant version of Afro-Brazilian ethnic identity vis-à-vis the state. 相似文献
47.
Kenneth N. O. Ghartey 《Commonwealth Law Bulletin》2020,46(2):249-269
The scope of directors’ duties forms perhaps the most important part of corporate governance. This paper considers the trajectory of the regulation of directors’ duties under Ghanaian company law from the Companies Act, 1963 (Act 179) to the Companies Act, 2019 (Act 992). Using the 2017 to 2019 financial institutions’ insolvencies in Ghana as a backdrop, it considers whether the scope, formulation and structure of directors’ duties within the new legislation is capable of promoting corporately-beneficial director behaviour. It also discusses whether the framework is apt to deal with similar lapses in corporate governance marked by reckless and opportunistic director behaviour. It discovers that Act 992 places a greater reliance on specific rules while retaining the largely principles-based regulatory technique adopted for regulating director conduct under Act 179. The overall tenor of the framework of directors’ duties under the new Act points to a firmer legislative view of the serious consequences of reckless director conduct. The paper concludes that the language of the framework regulating director conduct is capable of promoting corporately beneficially director behaviour and is also apt to deal with the kind of lapses in corporate governance which led to mass financial sector insolvencies in Ghana. 相似文献
48.
Matthew C. Benwell Alejandro F. Gasel Andres Núñez 《Bulletin of Latin American research》2020,39(4):424-438
This paper draws on recent research examining feminist and everyday geopolitics to focus on the relatively neglected domestic sphere as a space where geopolitical events like the Falklands/Malvinas war are learnt, (re)produced, remembered and contested by young people. It presents qualitative data drawn from interviews with young people from Argentina (Río Gallegos) and the Falkland Islands (Stanley), locations with intimate connections to the 1982 war. It argues that research in domestic environments that engages the familial relations, objects and practices that embody geopolitical pasts can help make sense of how young people (are able to) express geopolitical agency. 相似文献
49.
Sabrina Zorbo M.S. Patrick P. J. M. H. Jeuniaux Ph.D. 《Journal of forensic sciences》2020,65(2):641-648
In the case of suspicious deaths, the technique of 1:1 taping is often used in Belgium. It consists of affixing a large number of adhesive tapes to the body of the victim. It is conventionally aimed at obtaining microtraces (e.g., fibers, hair) and is usually not used for DNA analysis. However, in some cases, DNA analysis of certain areas of interest identified on the 1:1 taping material can offer a last resort solution. The four-step method that is described in this article involves the selection of areas of interest on the body (Step 1), the selection of the corresponding tapes (Step 2), the decontamination of the tapes (Step 3), the selection of areas of interest on the tapes, for DNA sampling (Step 4). The method is illustrated by its successful application in four murder cases. In each case, DNA profiles of good quality could be identified, including profiles of persons different from the victim. 相似文献
50.
Ahmet Içduygu 《Third world quarterly》2020,41(3):415-433
AbstractAlthough the Syrian conflict continues, local and global stakeholders have already begun to consider the return of the six million refugees, especially as neither the option of local integration in the countries of first asylum nor that of resettlement to third countries is seen as a realistic possibility. Elaborating on the return debates in Turkey, Lebanon and Jordan, we relate the politicisation of this question to the growing acceptance of the option of voluntary and involuntary repatriation in the international refugee regime as well as to policies and public opinion. We argue, based on empirical fieldwork, that any debate about the return of Syrian refugees is problematic, since the conditions of safety, voluntariness and sustainability are not fulfilled. Further, returns should not be left entirely to the individual hosting states and actors in the region but should be carried out in collaboration with representative authorities in Syria and the mediation of international organisations upon full resolution of conflict. 相似文献