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关键词： Category  

关键词： n-exact category   contractible sequence   idempotent complete category  

摘要： An n-exact category is a pair consisting of an additive category and a class of sequences with n + 2 terms satisfying certain axioms. We introduce n-weakly idempotent complete categories. Then we prove that an additive n-weakly idempotent complete category together with the class C-n of all contractible sequences with n + 2 terms is an n-exact category. Some properties of the class C-n are also discussed.

关键词： Geometrical symmetric powers   lambda-structures   Nisnevich sheaves   A(1)-homotopy theory   Admissible categories  

摘要： Symmetric powers of quasi-projective schemes can be extended via Kan extensions to geometrical symmetric powers of motivic spaces. In this work, we study geometrical symmetric powers and compare them with various symmetric powers in the unstable and stable A(1)-homotopy category of schemes over a field. (C) 2019 Elsevier B.V. All rights reserved.

摘要： We show that the blocks of category O for the Lie superalgebra q(n)(C) associated to half-integral weights carry the structure of a tensor product categorification for the infinite rank Kac-Moody algebra of type C-infinity. This allows us to prove two conjectures formulated by Cheng, Kwon and Wang. We then focus on the full subcategory consisting of finite-dimensional representations, which we show is a highest weight category with blocks that are Morita equivalent to certain generalized Khovanov arc algebras.

关键词： Glycerophospholipids   Vegetable oils   Extra-virgin olive oil   Virgin olive oil   Refined olive oil   Mass spectrometry   Liquid chromatography  

摘要： Glycerophospholipids (GPLs) constitute a chemical family within the saponifiable fraction of vegetable oils. GPLs have been scarcely studied in edible oils owing to the lack of sensitive and selective analytical methods. We have developed a method for identification, confirmation and relative quantitation of GPLs in vegetable oils. The method is based on solid-phase extraction (SPE) for isolation of GPLs and determination by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). As proof of concept, the approach has been applied to characterize GPLs in different olive oil categories, thus revealing compositional changes, which could be explained by factors such as the quality of fruits and the extraction process. Families such as glycerophosphatidic acids and phosphatidylglycerides are remarkable because of their capability to discriminate virgin olive oils from the rest of categories. These results open a door to additional studies targeted at the identification of olive oil quality by monitoring these lipids.

关键词： Screening   Algorithm   Eating disorders   General practice   SCOFF questionnaire  

摘要： Background We evaluated the performance of a clinical algorithm (Expali (TM)), combining two or more positive answers to SCOFF questionnaire with Body Mass Index (BMI), to identify four Broad Categories of eating disorders (ED) derived from DSM-5. Methods The clinical algorithm (Expali (TM)) was developed from 104 combinations of BMI levels and answers to five SCOFF questions with at least two positive answers. Two senior ED physicians allocated each combination to one of the four Broad Categories of ED derived from DSM-5: restrictive disorder, bulimic disorder, hyperphagic disorder and other unspecified ED diagnosed by ED clinicians. The performance of Expali (TM) was evaluated on data from 206 patients with ED. Sensitivity, specificity values and Youden index were calculated for each category. Results The 206 patients were diagnosed as follows: 31.5% restrictive disorder, 18.9% bulimic disorder, 40.8% hyperphagic disorder and 8.8% other ED. The sensitivity of Expali (TM) for restrictive, bulimic, hyperphagic and other unspecified ED were respectively: 76.9, 69.2, 79.7 and 16.7%. The Youden index was respectively 0.73, 0.57, 0.67 and 0.07. Conclusions In a SCOFF-positive ED population (at least two positive answers), the clinical algorithm Expali (TM) demonstrated good suitability by correctly classifying three of the four Broad Categories of eating disorders (restrictive, bulimic and hyperphagic disorder). It could be useful both to healthcare professionals and the general population to enable earlier detection and treatment of ED and to improve patient outcomes.

关键词： “断断续续”   词类标注   双层词类范畴理论   语料库  

摘要： “断断续续”一词在各大主流汉语词典及汉英词典中的词类标注存在较大分歧,笔者基于国家语委语料库和北京大学中国语言学研究中心语料库,以双层词类范畴化理论为指导原则,对“断断续续”一词在语料库中的词类进行统计分析,最后判断出其在语言系统层面的规约化用法,进而尝试性地对“断断续续”一词标注为形副兼类词,并进行解释和配例,以期对汉语词典及汉英词典的编撰有所启示。

关键词： Category discovery   Contour analysis   Interpretability   Leaf shape   Morphological description  

摘要： The categorical description of leaf shapes is of paramount importance in ecology, taxonomy and paleobotanical studies. Classification systems proposed by domain experts support these descriptions. Despite the importance of these visual descriptive systems, classifications based on this expert’s knowledge may be ambiguous or limited when representing shapes in unknown scenarios, as expected for biological exploratory domains. This work proposes a novel strategy to automatically discover the shape categories in a set of unlabeled leaves by only using the leaf-shape information. In particular, we overcome the task of discovering shape categories from different plant species for three different biological settings. The proposed method may successfully infer the unknown underlying shape categories with an F-score greater than 92%. The approach also provided high levels of visual interpretability, an essential requirement in the description of biological objects. This method may support morphological analysis of biological objects in exploratory domains.

关键词： Recovery speed   N170   Faces   Chinese characters  

摘要： Neural selectivity of N170 responses is important for understanding face, word, and object processing in the brain. However, the recovery times of neural selective responses remain unclear. In the present study, we used an adaptation paradigm to test the recovery speed of N170 responses to faces and Chinese characters. The findings revealed that recovery of N170 responses elicited by faces occurred between 1400 and 1800 ms after stimulus onset, whereas those elicited by Chinese characters occurred between 600 and 800 ms. These results demonstrate that N170 responses involved in the processing of faces and Chinese characters exhibit category sensitive recovery speeds.

摘要： There are no studies of long-term worsening renal function (WRF) in heart failure (HF) with different ejection fraction (EF) groups. The aim was to compare incidence of, associations with and prognostic impact of WRF in HF with preserved (HFpEF), mid-range (HFmrEF), and reduced EF (HFrEF). The Swedish Heart Failure Registry (SwedeHF) was merged with the Stockholm Creatinine Measurement (SCREAM) registry 2006 to 2010. The associations between EF and WRF (>= 25% decrease in eGFR) and the associations between WRF25-49% and WRF >= 50% within year one and subsequent all-cause mortality were all assessed with multiadjusted Cox regression. Of 7,154 patients, 41.6% of HFpEF versus 34.5% and 35.4% of HFmrEF and HFrEF patients developed WRF >= 25% during year one. The WRF risk was higher in HFpEF (reference) than in HFmrEF, hazard ratio (95% confidence interval) 0.890 (0.794 to 0.997) and HFrEF 0.870 (0.784 to 0.965). WRF within year one was strongly associated with subsequent long-term mortality in all EF groups, yielding adjusted HRs with WRF25-49% and WRF >= 50%: HFpEF, 1.101 (0.913 to 1.328) and 2.096 (1.652 to 2.659), in HFmrEF 1.654 (1.353 to 2.022) and 2.375 (1.807 to 3.122) and in HFrEF 1.212 (1.060 to 1.386) and 1.694 (1.412 to 2.033). In conclusion, the long-term WRF risk was high in HF and highest in HFpEF. WRF was strongly associated with mortality in all EF groups, although in HFpEF only with the most severe WRF. (C) 2019 Elsevier Inc. All rights reserved.