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21.
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
22.
ABSTRACTMany liberals have been immodest in postulating that their own progressive, secular liberalism is the only one that can be justified in public reason. In Liberalism’s Religion, I articulate a more modest theory of liberalism and religion. While I personally endorse progressive secular liberalism, I argue that it is only one of the reasonable conceptions of liberal justice. This liberal modesty has profound, hitherto unnoticed implications for (i) the role of religious arguments in the public sphere, (ii) the legitimacy of religious establishment, and (iii) the justifiability of religious exemptions. In this article, I defend these three claims by providing replies to my critics. 相似文献
23.
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
24.
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
25.
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
26.
Numerous accounts reveal that congressional leaders often secure “hip‐pocket votes” or “if you need me” pledges from rank‐and‐file legislators. These are essentially options on votes. Leaders exercise sufficient options—pay legislators to convert to favorable votes—when those options will yield victory. Otherwise, they release the options. A model shows that this optimal strategy for leaders produces many small victories, few small losses, and losses that are, on average, larger than victories. We find precisely these patterns, hence strong evidence for vote options, in Congressional Quarterly key votes from 1975 through 2001 and in non‐key votes from the 106th Congress (1999–2000). 相似文献
27.
In 1991 the FCC implemented a price cap plan for local exchange carriers' interstate access service designed to deal with the regulatory boundaries problem arising from the breakup of AT&T in 1984. The experience with the price cap plan demonstrates the difficulty of predicting productivity growth accurately and makes clear that regulators cannot depend upon a pure price cap plan to keep prices within a reasonable range of costs. With periodic reviews to readjust plan parameters, however, a price cap plan can maintain the rate-of-return close to the target rate-of-return without diminishing the price cap plan's incentives for efficient production. A simple method of recalculating the X-factor based on the rate-of-return over the previous three years worked well in simulations. If this procedure had been used over the price cap period 1991 to 2000, prices would have been 20 percent lower and expenditures on LECs' telecommunications service subject to a price cap would have been $3.8 billion lower. 相似文献
28.
While the concepts of race and ethnicity have been abused historically, they are potentially invaluable in epidemiology and public health. Epidemiology relies upon variables that help differentiate populations by health status, thereby refining public health and health care policy, and offering insights for medical science. Race and ethnicity are powerful tools for doing this. The prerequisite for their responsible use is a society committed to reducing inequalities and inequities in health status. When this condition is met, it is irresponsible not to utilize these concepts. 相似文献
29.
Ellen K. Marshall Ph.D. 《Journal of Police and Criminal Psychology》2006,21(1):62-71
The present study measured the existence of traumatic stress symptomatology as reported by certified law enforcement officers
within the State of Delaware. A questionnaire was devised which documented age, sex, race, education, years of service, marital
status, children, rank, position, and shift work. The questionnaire was divided into parts which assessed the exposure and
the frequency of specific traumatic incidents experienced in the line of duty, and the frequency of experienced traumatic
symptomatology criteria: re-experiencing, numbing, and arousal. 相似文献
30.