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关键词： Algebra epimorphism   d-abelian category   d-cluster tilting subcategory   d-homological pair   d-pseudoflat morphism   functorially finite subcategory   higher homological algebra   wide subcategory  

摘要： A subcategory of an abelian category is wide if it is closed under sums, summands, kernels, cokernels, and extensions. Wide subcategories provide a significant interface between representation theory and combinatorics. If (I) is a finite dimensional algebra, then each functorially finite wide subcategory of mod( (I)) is of the form 0* ( mod(F)) in an essentially unique way, where F is a finite dimensional algebra and (I) ci> F is an algebra epimorphism satisfying TorT(F, F) = 0. Let C mod((I)) be a d-cluster tilting subcategory as defined by Iyama. Then is a d-abelian category as defined by Jasso, and we call a subcategory of wide if it is closed under sums, summands, d-kernels, d-cokernels, and d-extensions. We generalise the above description of wide subcategories to this setting: Each functorially finite wide subcategory of is of the form 0* (1) in an essentially unique way, where (I) F is an algebra epimorphism satisfying Tord (F, F) = 0, and C mod(F) is a d-cluster tilting subcategory. We illustrate the theory by computing the wide subcategories of some d-cluster tilting subcategories C mod((I)) over algebras of the form (I) = kAmArad kA,X.

关键词： Category transition   Category hierarchy   Representation learning   Collective POI   Uncertain check-in   Next POI recommendation  

摘要： Most existing next POI recommendation studies rely on users' certain check-ins at individual POIs (e.g., Italian restaurant). In reality, users may leave some uncertain check-ins in the places (e.g., shopping mall), which are named as collective POIs. It indicates that we cannot always access users precise check-ins at collective POIs, thus existing approaches fail to work well. To this end, we propose a new research problem, that aims to recommend next individual POIs with uncertain check-ins at collective POIs. It is, however, difficult to learn complete and accurate users' check-in transition patterns with uncertain check-ins. Besides, uncertain check-ins aggravate the cold start issue, as the individual POIs inside collective POIs cannot be observed in users' historical check-ins. To tackle these challenges, we devise a novel hierarchical category transition (HCT) framework, which exploits category transitions at different layers to model users' preference transition patterns in different granularity. By doing so, HCT predicts users' preferred categories inside collective POIs. As bounded to specific categories, HCT further adopts hierarchical dependencies between POIs and categories to capture the semantic relatedness of POIs, thus easing the cold start issue. Empirical studies on multiple datasets show the superiority of HCT against state-of-the-art algorithms. (C) 2020 Elsevier Inc. All rights reserved.

关键词： Direct sum   Biproduct   C*   documentclass[12pt]{minimal}   usepackage{amsmath}   usepackage{wasysym}   usepackage{amsfonts}   usepackage{amssymb}   usepackage{amsbsy}   usepackage{mathrsfs}   usepackage{upgreek}   setlength{   oddsidemargin}{-69pt}   begin{document}$$   hbox {C}*$$   end{document}-category   W*   documentclass[12pt]{minimal}   usepackage{amsmath}   usepackage{wasysym}   usepackage{amsfonts}   usepackage{amssymb}   usepackage{amsbsy}   usepackage{mathrsfs}   usepackage{upgreek}   setlength{   oddsidemargin}{-69pt}   begin{document}$$   hbox {W}*$$   end{document}-category   Category of Hilbert spaces  

摘要： When formulating universal properties for objects in a dagger category, one usually expects a universal property to characterize the universal object up to unique unitary isomorphism. We observe that this is automatically the case in the important special case of C*-categories, provided that one uses enrichment in Banach spaces. We then formulate such a universal property for infinite direct sums in C*-categories, and prove the equivalence with the existing definition due to Ghez, Lima and Roberts in the case of W*-categories. These infinite direct sums specialize to the usual ones in the category of Hilbert spaces, and more generally in any W*-category of normal representations of a W*-algebra. Finding a universal property for the more general case of direct integrals remains an open problem.

关键词： Causal inference   Negative control   Semiparametric inference   Unmeasured confounding  

摘要： Unmeasured confounding is a threat to causal inference in observational studies. In recent years, the use of negative controls to mitigate unmeasured confounding has gained increasing recognition and popularity. Negative controls have a long-standing tradition in laboratory sciences and epidemiology to rule out non-causal explanations, although they have been used primarily for bias detection. Recently, Miao and colleagues have described sufficient conditions under which a pair of negative control exposure and outcome variables can be used to identify non-parametrically the average treatment effect (ATE) from observational data subject to uncontrolled confounding. We establish non-parametric identification of the ATE under weaker conditions in the case of categorical unmeasured confounding and negative control variables. We also provide a general semiparametric framework for obtaining inferences about the ATE while leveraging information about a possibly large number of measured covariates. In particular, we derive the semiparametric efficiency bound in the non-parametric model, and we propose multiply robust and locally efficient estimators when non-parametric estimation may not be feasible. We assess the finite sample performance of our methods in extensive simulation studies. Finally, we illustrate our methods with an application to the post-licensure surveillance of vaccine safety among children.

关键词： Similarity   Semantics   Conceptual structure   Taxonomic categories   Thematic association   N400  

摘要： Human similarity judgments do not reliably conform to the predictions of leading theories of psychological similarity. Evidence from the triad similarity judgment task shows that people often identify thematic associates like DOG and BONE as more similar than taxonomic category members like DOG and CAT, even though thematic associates lack the type of featural or relational similarity that is foundational to theories of psychological similarity. This specific failure to predict human behavior has been addressed as a consequence of education and other individual differences, an artifact of the triad similarity judgment paradigm, or a shortcoming in psychological accounts of similarity. We investigated the judged similarity of semantically-related concepts (taxonomic category members and thematic associates) as it relates to other task-independent measures of semantic knowledge and access. Participants were assessed on reading and language ability, then event-related potentials (ERPs) were collected during a passive, sequential word reading task that presented pseudowords and taxonomically-related, thematically-related, and unrelated word sequences, and, finally, similarity judgments were collected with the classic two-alternative forced-choice triad task. The results uncovered a correspondence between ERP amplitude and triad-based similarity judgments-similarity judgment behavior reliably predicts ERP amplitude during passive word reading, absent of any instruction to consider similarity. It was also found that individual differences in reading and language ability independently predicted ERP amplitude. This evidence suggests that similarity judgments are driven by reliable patterns of thought that are not solely rooted in the interpretation of task goals or reading and language ability.

关键词： Jellyfish partition category   Partition algebra   Alternating group   Representation theory  

摘要： For each positive integer n, we introduce a monoidal category JP( n) using a generalization of partition diagrams. When the characteristic of the ground field is either 0 or at least n, we show JP(n) is monoidally equivalent to the full subcategory of Rep(A(n)) whose objects are tensor powers of the natural n-dimensional permutation representation of the alternating group A(n).

关键词： Blastocyst   In vitro fertilization   Obesity   BMI   Race  

摘要： Purpose There are well-documented racial and ethnic disparities for in vitro fertilization (IVF) outcomes, including disparities in clinical pregnancy and live birth rate. Obesity has also been associated with an increase in the risk of infertility and reduction in the efficacy of fertility treatment. However, there are limited data regarding the potential effect of race and obesity on in vitro embryo development. The purpose of this study was to determine whether blastocyst formation rates vary with race and body mass index (BMI). Methods This retrospective analysis included 1134 fresh autologous cycles (N = 8266 embryos), which took place from January 2013 to December 2016. Women were categorized as Caucasian, Asian (not Indian), and Indian (South Asian) and by BMI categories (normal, overweight, and obese). Regression analyses were performed using race and BMI as the primary predictor variables and blastocyst formation as the outcome. Results Compared to Caucasian, the adjusted OR for blastocyst development was 0.85 (95% CI 0.72-1.00) for Asian women and 1.15 (95% CI 0.95-1.38) for Indian women. Women who were overweight (aOR 0.93;95% CI 0.77-1.12) or obese (aOR 0.92;95% CI 0.74-1.12) had similar odds of blastocyst formation comparing to women with normal BMI. Furthermore, analyses examining combined effects of race and BMI revealed no differences in blastocyst formation among Asian or Indian women with varied BMI categories compared to Caucasian women with normal BMI. Conclusion Blastocyst formation did not differ based on race or BMI.

关键词： Problem gambling   Problem gambling severity index   PGSI   Latent class analysis   Help-seeking   Gambling services   Validity  

摘要： Background: The Problem Gambling Severity Index (PGSI) was intended for use in epidemiological research with gamblers across the continuum of risk. Its utility within clinical settings, where the majority of clients are problem gamblers, has been brought into question. Aims: (1) Identify refined categories for the problem gambling category of the PGSI in help-seeking gamblers;(2) Validate these categories using the Gambling Symptom Assessment Scale (G-SAS);(3) Explore the relationship of these categories with indices of gambling and help-seeking behaviour. Methods: Secondary data analysis of help-seeking problem gamblers from the Australian online gambling counselling/support service (Gambling Help Online [GHO]) from October 2012 to December 2015 (n = 5,881) and trial data evaluating an Australian online self-directed program for gambling (GAMBLINGLESS;n = 198). Both datasets included the PGSI, gambling frequency and expenditure. The GAMBLINGLESS dataset also included the G-SAS and help-seeking behaviour. Results: A Latent Class Analysis, using GHO data, identified a 2-class solution. Multiple analytical methods identified a cut-off value of >= 19 distinguishing this 2-class solution (low problem severity: Median = 16;high problem severity: Median = 23). High problem severity gamblers had increased odds of being categorised in the higher GSAS category, greater gambling expenditure and having sought face-to-face support. The refined categories were not associated with gambling frequency, distance-based or self-directed help-seeking. Conclusion: These findings are consistent with a stepped-care approach, whereby individuals with higher severity may be better suited to more intensive interventions and individuals with lower severity could commence with less intensive interventions and step-up to intensive interventions.

关键词： Bott-Samelson variety   Equivariant cohomology   Category  

摘要： We consider all Bott-Samelson varieties BS(s) for a fixed connected semisimple complex algebraic group with maximal torus T as the class of objects of some category. The class of morphisms of this category is an extension of the class of canonical (inserting the neutral element) morphisms BS(s) -> BS(s'), where s is a subsequence of s'. Every morphism of the new category induces a map between the T-fixed points but not necessarily between the whole varieties. We construct a contravariant functor from this new category to the category of graded H-T(center dot) (pt)-modules coinciding on the objects with the usual functor H-T(center dot) of taking T-equivariant cohomologies. We also discuss the problem how to define a functor to the category of T-spaces from a smaller subcategory. The exact answer is obtained for groups whose root systems have simply laced irreducible components by explicitly constructing morphisms between Bott-Samelson varieties (different from the canonical ones).

关键词： Hand hygiene compliance   Patients' family members   Hospital   India  

摘要： Introduction: In India, due to manpower constraints, patients' family members are often actively involved in healthcare activities of their near and dear ones. They have significant contact with the patient at all World Health Organization (WHO) 'five moments for hand hygiene'. This study analysed the impact of decade-long awareness campaigns on the hand hygiene compliance (HHC) by our patients' carers. Methods: Trained infection control nurses observed the HHC at each of the five moments for patients' attendants in different hospital settings from January 2014 to December 2018. Compliance was calculated as percentage of events divided by total opportunities. Findings: A total of 7302 opportunities were observed with an overall compliance of 46.1% (35.5% in 2014 to 48.2% in 2018, P < 0.0001). Compliance at WHO moments 1, 2, 3, 4, and 5 was 51.0%, 47.4%, 67.6%, 48.8%, and 24.3% respectively. Among family members, mothers of newborns had a much higher HHC (77%) than others (44.5%) (P < 0.0001). Also, the compliance was higher in medical versus surgical wards and in paediatric wards versus adult wards (P < 0.0001 in both). Conclusion: This is the first study on family members' HHC in a hospital setting in a low-and middle-income country. The study shows that family members, once trained, exhibit fairly good HHC while caring for their patients, especially mothers of newborns. It is worthwhile empowering and educating patient attendants about the importance and process of hand hygiene as it is likely to result in immense benefit for patients. (C) 2019 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.