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61.
We consider asymptotics of ratios of random characteristic polynomials associated with orthogonal polynomial ensembles. Under some natural conditions on the measure in the definition of the orthogonal polynomial ensemble we establish a universality limit for these ratios. 相似文献
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Eugene Mills 《Acta Analytica》2013,28(1):19-30
We are beings endowed with “personal capacities”—the capacity for reason, for a concept of self, perhaps more. Among ontologically salient views about what else we are, I focus on the “Big Three.” According to animalism, we are animals that have psychological properties only contingently. According to psychologistic materialism, we are material beings; according to substance dualism, we are either immaterial beings or composites of immaterial and material ones; but according to both psychologistic materialism and substance dualism, we essentially have some psychological properties. I argue that—contrary to what has been argued and is natural to think—none of the Big Three yields different assignments of moral status to early fetuses from any of the others, and consequently the moral status of early abortion doesn’t depend on which (if any) of these views of personal ontology is correct. 相似文献
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Pesticide residue analysis is an important part of food quality control. Three of the most widely used methods are the DFG S19 (extraction with acetone), the ChemElut method (extraction with methanol), and QuEChERS (quick, easy, cheap, effective, rugged, safe; acetonitrile‐based). Despite many developments in the field of sample preparation, matrix effects are still one of the most disturbing problems in routine analysis. In this study, we compare the matrix effects in LC–MS analysis after using these three methods in pesticide analysis. Using postcolumn infusion, we were able to visualize all suppressions over the whole chromatogram in matrix‐effect profiles. Recently, we also presented a system for the determination of up to 300 pesticides from various kinds of fruit and vegetables. For the measurement, we injected an aliquot of a raw acetonitrile extract. The subsequent cleanup was carried out fully automated by a multidimensional LC. Matrix compounds and analytes are separated in the first dimension on a hydrophilic interaction LC column. In this study, we also compared this new approach with the classical methods. The matrix‐effect profiles showed less suppression with the hydrophilic interaction LC‐based cleanup. A final evaluation of the partitioning steps of all methods confirmed the benefits of the chromatographic cleanup approach. 相似文献
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Postnikov Eugene B. Pikalov Ivan Yu. Chora̧żewski Mirosław 《Journal of solution chemistry》2022,51(11):1311-1333
Journal of Solution Chemistry - Recently ionic liquids have been considered as prospective substances for application as heat transfer fluids, which requires accurate knowledge of their thermal... 相似文献
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Tong Su Yafei Wang Yi Liu William G. Branton Eugene Asahchop Christopher Power Bei Jiang Linglong Kong Niansheng Tang 《Entropy (Basel, Switzerland)》2020,22(11)
Distance weighted discrimination (DWD) is an appealing classification method that is capable of overcoming data piling problems in high-dimensional settings. Especially when various sparsity structures are assumed in these settings, variable selection in multicategory classification poses great challenges. In this paper, we propose a multicategory generalized DWD (MgDWD) method that maintains intrinsic variable group structures during selection using a sparse group lasso penalty. Theoretically, we derive minimizer uniqueness for the penalized MgDWD loss function and consistency properties for the proposed classifier. We further develop an efficient algorithm based on the proximal operator to solve the optimization problem. The performance of MgDWD is evaluated using finite sample simulations and miRNA data from an HIV study. 相似文献