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关键词： Mouse   Learning   Memory   Procedural memory   Reference memory   Declarative-like memory   Hippocampus  

摘要： Different memory systems operate in parallel to support behaviour. To evaluate procedural and reference subcategories of long-term memory as early as possible in the mouse, the Helico Maze (HM) was developed. BALB/c AnNCrl (BALB), C57BL/6JRj (C57) and DBA/2 JRj (DBA) mice were trained on this new maze. The three strains learned how to use the HM (procedural memory), and they then learned and remembered four odour-reward associations (reference memory). The three strains differed in the number of correct responses. BALB mice showed better performance than C57 and DBA mice. The results of the first block of each session revealed that only the BALB and C57 mice remembered the odour-reward associations. DBA mice needed to relearn the associations each day. With this new apparatus, the number of olfactory cue-reward associations was increased from 2 to 4 in comparison to a previous olfactory tubing maze. Consequently, a supplementary effort of memory was required, and the chance level was decreased from 50 % to 25 %. Thus, in several important respects, the HM can be considered to measure the hippocampus-dependent behaviour of the mouse, allowing to study, as early as possible in young mice, the different subcategories of long-term memory, such as those observed in humans.

关键词： Projective functor   Whittaker functor   Whittaker modules  

摘要： We show that the Whittaker functor on a regular block of the BGG-category O of a semisimple complex Lie algebra can be obtained by composing a translation to the wall functor with Soergel and Milicic's equivalence between the category of Whittaker modules and a singular block of O. We show that the Whittaker functor is a quotient functor that commutes with all projective functors and endomorphisms between them. (C) 2021 Elsevier Inc. All rights reserved.

关键词： Extriangulated categories   Auslander-Reiten-Serre duality   Serre duality   Auslander bijection   Restricted Auslander bijection  

摘要： Extriangulated categories were introduced by Nakaoka and Palu, which unify exact categories and extension-closed subcategories of triangulated categories, and recently Iyama, Nakaoka and Palu investigated Auslander-Reiten theory in terms of Auslander-Reiten-Serre duality in extriangulated categories. In this paper, we introduce the notion of Serre duality, as a special type of Auslander-Reiten-Serre duality, and then give an equivalent condition for the existence of Serre duality. On the other hand, we study a bijection triangle in extriangulated categories which involves the restricted Auslander bijection and Auslander-Reiten-Serre duality. Let Rbe a commutative artinian ring. We show that the restricted Auslander bijection holds true in Hom-finite R-linear KrullSchmidt extriangulated categories having Auslander-ReitenSerre duality, and especially obtain the Auslander bijection in Hom-finite R-linear Krull-Schmidt extriangulated categories having Serre duality. We also give some applications, and in particular, we show that a conjecture given by Ringel holds true in this setting. (C) 2021 Elsevier Inc. All rights reserved.

关键词： Extriangulated category   Auslander-Reiten E-triangle   Relations of Grothendieck group   Locally finite extriangulated category   Dense resolving subcategory  

摘要： Extriangulated categories were introduced by Nakaoka and Palu to give a unification of properties in exact categories and triangulated categories. We consider in this article the Grothendieck group K-0(C) of an extriangulated category C. We show that a locally finite extriangulated category Calways has almost split extensions and in this case the relations of the Grothendieck group K-0(C) are generated by the AuslanderRieten E-triangles. We give a partial converse result when restricting to the triangulated categories with a cluster tilting subcategory: in the triangulated category with a cluster tilting subcategory, the relations of the Grothendieck group are generated by AR-triangles if and only if the triangulated category is locally finite. We also show that there is a one-toone correspondence between subgroups of K-0(C) containing the image of G and dense G-(co)resolving subcategories of Cw here Ga generator of C, which generalizes results about classifying subcategories of a triangulated or exact category C by subgroups of K-0(C). (C) 2021 Published by Elsevier Inc.

关键词： Assortment planning   Retailing   Brand identity   Marketing strategy   Product management   Fast moving consumer goods   Brick-and-Mortar retailing   Category evolution   Consumer packaged goods   Niche brands  

摘要： Purpose This study aims to focus on the role of niche brands in online retailer assortments and the general market positions of niche brands, no prior study has explicitly focused on if and when brick-and-mortar retailers should include niche brands in their category assortments. Design/methodology/approach The authors empirically analyze the category performance implications of focusing assortments on niche brands, at the expense of mainstream brands, in two product categories that have significant niche brand presence, namely, coffee and beer. The empirical data include sales, distribution and marketing tactical information for 50 US geographic markets from 2001-2011. Findings This research finds that a mainstream brand focus has a generally positive impact on category performance. However, a store's strategic shift toward niche brands is beneficial in certain cases such as when a store has higher average prices or product form variety or when they are part of a powerful chain. The authors also find that a niche brand focus strategy is becoming increasingly viable over time for brick-and-mortar retailers. Originality/value Little is known about the parameters that might make a brick-and-mortar retailer more or less likely to pursue a niche brand focus strategy and when doing so might improve category performance. This analysis helps clarify the conditions under which a brick-and-mortar retailer may experience category level sales increases from focusing assortments on niche brands.

关键词： genome-wide association studies   GWAS   phenome-wide association studies   PheWAS   ordinal categorical data   mixed model approach   proportional odds logistic mixed model   POLMM   UK Biobank   saddlepoint approximation   unbalanced phenotypic distribution   food and other preferences   genetic relationship matrix   GRM  

摘要： In genome-wide association studies, ordinal categorical phenotypes are widely used to measure human behaviors, satisfaction, and preferences. However, because of the lack of analysis tools, methods designed for binary or quantitative traits are commonly used inappropriately to analyze categorical phenotypes. To accurately model the dependence of an ordinal categorical phenotype on covariates, we propose an efficient mixed model association test, proportional odds logistic mixed model (POLMM). POLMM is computationally efficient to analyze large datasets with hundreds of thousands of samples, can control type I error rates at a stringent significance level regardless of the phenotypic distribution, and is more powerful than alternative methods. In contrast, the standard linear mixed model approaches cannot control type I error rates for rare variants when the phenotypic distribution is unbalanced, although they performed well when testing common variants. We applied POLMM to 258 ordinal categorical phenotypes on array genotypes and imputed samples from 408,961 individuals in UK Biobank. In total, we identified 5,885 genome-wide significant variants, of which, 424 variants (7.2%) are rare variants with MAF < 0.01.

关键词： Elite   cycling   power output   heart rate   performance  

摘要： This study analyses the influence of race category and result on the demands of professional cycling races. In total, 2920 race files were collected from 20 male professional cyclists, within a variety of race categories: Single-day (***) and multi-day (***) World Tour races, single-day (***) and multi-day (***) Hors Categorie races and single-day (1.1) and multi-day (2.1) category 1 races. Additionally, the five cycling "monuments" were analysed separately. Maximal mean power outputs (MMP) were measured across a broad range of durations. Volume and load werelargetovery largely(d = 1.30-4.80) higher in monuments compared to other single-day race *** were observed for most intensity measures between different single-day race categories, with only RPE and sRPE center dot km(-1)beingmoderately(d = 0.70-1.50) higher in the monuments. Distance and duration weresmalltomoderately(d = 0.20-0.80) higher in *** races compared to *** and 2.1 multi-day race categories with only small differences in terms of load and intensity. Generally, higher ranked races (i.e. Monuments, *** and GT) tend to present with lower shorter-duration MMPs (e.g. 5-120 sec) compared to races of "lower rank" (with less differences and/or mixed results being present over longer durations), potentially caused by a "blunting" effect of the higher race duration and load of higher ranked races on short duration MMPs. MMP weresmalltolargelyhigher over shorter durations (<5 min) for a top-10 result compared to no top-10, within the same category.

关键词： Latent interaction   categorical data   latent moderated structural equations  

摘要： Latent moderated structural equations (LMS) is a popular method in estimating latent interaction effects. Mplus has implemented a variant of LMS (LMS-cat) that uses categorical confirmatory factor analysis to handle ordered-categorical indicators. We conducted a simulation study to examine the performance of the LMS-cat in varying sample size, interaction effect size, missing data rate and scenario, as well as number and symmetry of item response category conditions. Results showed that the LMS-cat is an excellent method in estimating structural parameters (i.e., interaction effect and lower-order effects). However, it could produce highly biased measurement parameters (i.e., factor loadings, and item category thresholds). We illustrated the LMS-cat by testing the interaction effect between participation in teachers` support activities and that of teachers` counterfactual activities (meditation, meditative movement, vigorous physical exercise) on teachers` sense of self-efficacy.

关键词： 工匠精神   匠   溯源   意义  

摘要： 当今时代,"工匠精神"复归,其浪潮一直在持续,因此对"匠"范畴的辨析符合新时期中国特色社会主义发展要求。"匠"范畴沟通了文学与艺术创作的界限,体现了知识分子人文精神与劳动阶级工匠"技艺"精神的融会贯通。探究"匠"范畴的意义衍变和"匠"范畴在古今文论衔接中的角色定位以及"匠"与文学创作的关联,不仅仅是对"匠"范畴的辨析,甚至是对古人和整个时代审美形态的探析。

关键词： 戏曲美学   美学范畴   安葵  

摘要： 在戏曲研究领域内,戏曲美学范畴研究一直相对薄弱,无论是戏曲美学范畴个案,还是戏曲美学范畴体系,都有着很大的研究提升空间。2020年安葵《戏曲美学范畴论》一书的出版,扎实推进了当前的戏曲美学范畴研究。该书表现出非常突出的四个特点,即:清晰而正确的方法论意识,戏曲美学范畴的提炼与确认,对戏曲美学范畴系统的勾勒,和以实践为导向的戏曲美学范畴研究。