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摘要： Motivation: High throughput and high content screening are extensively used to determine the effect of small molecule compounds and other potential therapeutics upon particular targets as part of the early drug development process. However, screening is typically used to find compounds that have a desired effect but not to identify potential undesirable side effects. This is because the size of the search space precludes measuring the potential effect of all compounds on all targets. Active machine learning has been proposed as a solution to this problem. Results: In this article, we describe an improved imputation method, Impute by Committee, for completion of matrices containing categorical values. We compare this method to existing approaches in the context of modeling the effects of many compounds on many targets using latent similarities between compounds and conditions. We also compare these methods for the task of driving active learning in well-characterized settings for synthetic and real datasets. Our new approach performed the best overall both in the accuracy of matrix completion itself and in the number of experiments needed to train an accurate predictive model compared to random selection of experiments. We further improved upon the performance of our new method by developing an adaptive switching strategy for active learning that iteratively chooses between different matrix completion methods.

关键词： Exact category   Semibrick   Wide subcategory   Schur's lemma  

摘要： We show that for a given exact category, there exists a bijection between semibricks (pairwise Hom-orthogonal set of bricks) and length wide subcategories (exact extension-closed length abelian subcategories). In particular, we show that a length exact category is abelian if and only if simple objects form a semibrick, that is, Schur's lemma holds. (C) 2021 Elsevier Inc. All rights reserved.

摘要： In this investigation we explore whether assessment of the risk of mortality can be refined by stratifying high-risk patients with pulmonary embolism (PE) according to whether they had cardiac arrest. We stratified high-risk patients according to whether they had shock but no cardiac arrest, or cardiac arrest diagnosed in the emergency department (ED). This was a retrospective cohort study based on administrative data from the Nationwide Emergency Department Sample (NEDS), 2016. Included patients were 274,227 who were admitted to the same hospital as the ED or died in the ED. This was 77% of 354,616 patients with pulmonary embolism seen in the ED in 2016. Patients were identified based on International Classification of Diseases, 10th Edition, Clinical Modification (ICD-10-CM) Codes. High-risk with no cardiac arrest were 4,317 of 274,227 (1.6%) and high-risk with cardiac arrest were 1,027 of 274,227 (0.4%). Mortality of high-risk patients who did not have cardiac arrest was 1,753 of 4,317 (41%). Mortality of high-risk patients who had cardiac arrest was 754 of 1027 (74%). Mortality increased with age in high-risk patients who did not have cardiac arrest, but mortality was not age-related in high-risk patients with cardiac arrest. In conclusion, high-risk patients with PE are a heterogeneous group and stratification according to whether they had cardiac arrest refines risk assessment. (C) 2021 Published by Elsevier Inc.

关键词： Cluster category   Skew-group algebra   Orbifold groupoid  

摘要： Given a certain triangulation of a punctured surface with boundary, we construct a new triangulated surface without punctures which covers it. This new surface is naturally equipped with an action of a group of order two, and its quotient by this action recovers the original surface. We show that the group acts on the quivers with potentials associated to the surfaces, and that their Ginzburg dg algebras are skew group algebras of each other, up to Morita equivalence. We then use these results to construct functors between the generalized cluster categories associated to the triangulations. This allows us to give a complete description of the indecomposable objects of these categories in terms of curves on the surface, when the surface has punctures and non-empty boundary. (c) 2021 Elsevier Inc. All rights reserved.

关键词： Tamari lattice   Fractionally Calabi-Yau category   Representation of poset  

摘要： We prove that the bounded derived category of the incidence algebra of the Tamari lattice is fractionally Calabi-Yau, giving a positive answer to a conjecture of Chapoton. The proof involves a combinatorial description of the Serre functor of this derived category on a sufficiently nice family of indecomposable objects. (c) 2021 Elsevier Inc. All rights reserved.

关键词： Categorical dynamics   Mapping torus   Flux group   Homological mirror symmetry   Noncommutative geometry  

摘要： This paper describes constructions in homological algebra that are part of a strategy whose goal is to understand and classify symplectic mapping tori. More precisely, given a dg category and an auto-equivalence, satisfying certain assumptions, we introduce a category M-phi-called the mapping torus category-that describes the wrapped Fukaya category of an open symplectic mapping torus. Then we define a family of bimodules on a natural deformation of M-phi, uniquely characterize it and using this, we distinguish M-phi from the mapping torus category of the identity. The proof of the equivalence of M-phi with wrapped Fukaya category is proven in a different paper ([17]). (C) 2021 Elsevier Inc. All rights reserved.

关键词： 税收维度社会范畴化   群体归属   税收遵从   税收社会认同  

摘要： 通过对现实世界的观察会发现,税收制度、税收负担相似的不同经济体,其纳税人的税收遵从呈现比较大的差异。这与税收征管的制度设计和成本投入有关,同时往往还与公共品提供规模与质量有密切的关系。但从时间序列上看,上述因素的改变确实可以影响税收遵从,除了路径的差异,还具有明显的时滞性。这除了与正式制度运行的惯性有关,还有其他非正式制度的影响。从社会学和社会心理学的视角看,税收维度的个人自我范畴化过程会影响税收遵从行为的内在演化机制。通过分析以税收维度初始个体自我范畴化为起点和以负面税收立场个体自我范畴化为起点的群体归属产生过程及其变迁,探究税收社会表征及其形成与演化的基本特征、路径,有助于进一步厘清税收维度的范畴化对税收遵从行为的影响。

关键词： “逸”范畴   清代   “逸品”   朴学  

摘要： 清代是“逸”范畴的理论深化期,以简为尚的朴学学风是“逸品”成为清代文艺审美风尚的重要原因之一,清人对“逸品”的高捧最终导致了“逸品”的泛化。崇尚学术的客观性、实证性,主张理性判断的清代学者随之掀起了对“伪逸品”的批判高潮,促进了“逸”范畴的健康发展。同时,随着“逸”论在清代诗学、词学、书画领域的全面繁荣与交融互释,“逸”范畴得到了前所未有的理论深化。

关键词： 汉学家译者   中国小说翻译   英语国家读者   范畴化   重新定位  

摘要： 本文从范畴化理论和斯戴宾(Stebbins)的阅读理论出发,对新时期汉学家有关英译中国小说读者范畴的观念和重新定位进行评述和理论化概括,进一步阐释和明确了英译中国小说读者范畴的构成、特征和分布形态。文章提出,对新时期的翻译读者进行定位,应充分认识新时期英译中国小说读者范畴的异质性、历史性和变动性等特征,明确中国文学国际声誉的实质,关注读者和出版者的双向认知关系,以及分众传播的趋势。在进行读者原型范畴化时,应避免认知定型的局限。开展新时期翻译读者的范畴化研究,对中国文化和文学"走出去"具有重要理论和实践意义。