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关键词： Deligne category   Thick tensor ideals   Periplectic Lie superalgebra   Categorification   Diagram algebras   Temperley-Lieb algebra   Fock space  

摘要： We construct a faithful categorical representation of an infinite Temperley-Lieb algebra on the periplectic analogue of Deligne's universal monoidal category. We use the corresponding combinatorics to classify thick tensor ideals in this periplectic Deligne category. This allows us to determine the objects in the kernel of the monoidal functor going to the module category of the periplectic Lie supergroup. We use this to classify indecomposable direct summands in the tensor powers of the natural representation, determine which are projective and determine their simple top.

关键词： Modular neural network   Interpretable machine learning   Image classification   Category hierarchy   Learning to learn  

摘要： Modular is a powerful and inherently hierarchical concept in the human brain to process a large variety of complex tasks. Converging evidence has shown several advantages to hierarchically modular network organizations in the human brain such as interpretability and evolvability of network function. Inspired by previous neuroscience studies, we propose MNN-CH, a novel modular neural network that is constructed with explored category hierarchy. The basic idea is learning to learn an optimized category hierarchy to decompose complex patterns. And specific patterns are imposed into corresponding modules to realize a transparent design of the neural network. Specifically, for a given classification task, each class or superclass is first represented as a prototype. Afterward, the category hierarchy is initially determined by investigating class similarity and gather similar ones to train each branch neural network (i.e., modular) separately. Finally, an error-driven prototype learning is introduced to refine the category hierarchy by updating the class-superclass affiliation. Experiment results on several image classification datasets show that our model has a good performance, especially in complex tasks. Beyond, we conduct an analysis to illustrate the tree-manner interpretability of the modular neural network. (c) 2021 Elsevier Inc. All rights reserved.

关键词： Hotel revenue management   Hedonic pricing   Online pricing   Price determinants   Pricing behaviour   Big data  

摘要： This research uses a big dataset of online prices published on *** by three-, four- and five-star hotels located in Madrid (Spain). Data is broadened by other sources, resulting in a rich set of context-, hotel- and offerbased variables. This research aims to determine the impact of these variables on the online room prices set by one representative sample, featuring the total pricing behaviour as well as per hotel categories. The variables considered, their extent and the insight per category represent a novelty and complement the literature on demand forecasting and hedonic pricing, enabling the improvement of optimisation techniques. The models, based on regression analysis with random effects, reveal a significant impact of the variables on room prices and a clearly distinct behaviour for five-star hotels. This research contributes to the scientific community and practitioners by showing the pricing dynamics behaviour of an important urban destination by star rating.

摘要： In this article, gentle algebras are realised as tiling algebras, which are associated to partial triangulations of unpunctured surfaces with marked points on the boundary. This notion of tiling algebras generalise the notion of Jacobian algebras of triangulations of surfaces and the notion of surface algebras. We use this description to give a geometric model of the module category of any gentle algebra.

关键词： Psychiatry   Medical Education  

摘要： To accomplish this, we used two complementary and anonymous surveys to determine each group of interns’ perceptions of the professional training and scope of practice of the other intern group. The instrument would greatly benefit from methods to establish reliability, and our sample size is small. [...]clinical psychology and psychiatry have a complicated relationship. Marcussen, M; Norgaard, B; Arnfred, S. The effects of interprofessional education in mental health practice: findings from a systematic review.

关键词： Cardiovascular diseases   Obesity  

关键词： Health inequalities   Social categories   Intersectionality   Mixed methods   Healthcare access   Maternal health   Zambia  

摘要： "Categorical thinking" in social science research has been widely criticised by feminist scholars for conceptualising social categories as natural, de-contextualised, and internally homogeneous. This paper develops and applies a mixed-methods approach to the study of health inequalities, using social categories meaningfully in order to challenge categorical thinking. The approach is demonstrated through a case study of socio-economic (SES) inequalities in maternal healthcare access in Zambia. This paper's approach responds to the research agenda set by intersectional social epidemiologists by considering potential heterogeneity within categories, but also by exploring the context-specific meaning of categories, examining explanations at multiple levels, and interpreting results according to mutually constitutive social processes. The study finds that meso-level institutions, "health service environments", explain a large share of SES inequalities in maternal healthcare access. Women's work, marital status, and levels of "autonomy" have heterogeneous implications for healthcare access across SES categories. Disadvantaged categories and their reproductive behaviours are stigmatised as 'backwards', in contrast to advantaged categories and their behaviours, which are associated with 'modernity' and 'development'. Challenging categorical thinking has important implications for social justice and health, by rejecting framings of a specific category as problematic or noncompliant, highlighting the possibility of change, and emphasising the political and structural nature of progress.

关键词： Derived category   Exact context   Localization   Noncommutative tensor product   Recollement  

摘要： A new method is established to construct recollements of derived categories of rings from exact contexts and noncommutative tensor products. This method is applicable to a large variety of situations, including Milnor squares, localizations, ring extensions and ring epimorphisms. (C) 2020 Elsevier B.V. All rights reserved.

关键词： basaloid   fine‐   needle aspiration (FNA)   Milan System for Reporting Salivary Gland Cytopathology (MSRSGC)   oncocytic   salivary gland neoplasm of unknown malignant potential (SUMP)  

摘要： BACKGROUND The salivary gland neoplasm of unknown malignant potential (SUMP) category reflects the cytomorphologic overlap and complexity of reporting salivary gland cytology in the Milan system. It includes neoplasms for which a diagnosis of a specific entity cannot be made and, more importantly, for which a carcinoma cannot be entirely excluded. For risk stratification, the subcategorization of SUMP based on the predominant cell type is recommended. This study was aimed at evaluating the risk of neoplasm (RON) and the risk of malignancy (ROM) of the basaloid and oncocytic subtypes of the SUMP category. METHODS A retrospective analysis of 482 salivary gland fine-needle aspirations from 2012 to 2019 resulted in 48 SUMP cases. The cytology of these cases was reviewed and reclassified as the basaloid or oncocytic subtype. Surgical follow-up was available for 36 cases. The RON and ROM for each subtype were calculated. RESULTS The RON and ROM were 100% and 23%, respectively, for monomorphic basaloid tumors and 88% and 58.8%, respectively, for monomorphic oncocytic tumors. The ROM for basaloid tumors was 8.3% without matrix/with minimal matrix and 60% with an nonfibrillary matrix. The ROM for oncocytic tumors was 50% without a cystic background and 60% with a cystic or mucinous background. The difference was not statistically significant for either of the subgroups. CONCLUSIONS Even though statistically not significant in our study, the differential ROMs within the oncocytic and basaloid subgroups help in the risk stratification of SUMP cases. Further subcategorization based on the stroma and background helps in limiting the differential diagnosis but does not necessarily add to the value of the risk stratification.

关键词： comorbidity   disaster preparedness   ICU   pandemic   SOFA score   triage  

摘要： BACKGROUND: The COVID-19 pandemic has led to unprecedented demand for ICUs, with the need to triage admissions along with the development of ICU triage criteria. However, how these criteria relate to outcomes in patients already admitted to the ICU is unknown, as is the incremental ICU capacity that triage of these patients might create given existing admission practices. RESEARCH QUESTION: What is the short- and long-term survival of low- vs high-priority patients for ICU admission according to current pandemic triage criteria? STUDY DESIGN AND METHOD: This study analyzed prospectively collected registry data (2007-2018) in 23 ICUs in Victoria, Australia, with probabilistic linkage with death registries. After excluding elective surgery, admissions were stratified according to existing ICU triage protocol prioritization as low (age >= 85 years, or severe chronic illness, or Sequential Organ Failure Assessment [SOFA] score = 0 or >= 12), medium (SOFA score = 8-11) or high (SOFA score = 1-7) priority. The primary outcome was long-term survival. Secondary outcomes were in-hospital mortality, ICU length of stay (LOS) and bed-day usage. RESULTS: This study examined 126,687 ICU admissions. After 5 years of follow-up, 1,093 of 3,296 (33%;95% CI, 32-34) of "low-priority" patients aged >= 85 years or with severe chronic illness and 86 of 332 (26%;95% CI, 24-28) with a SOFA score >= 12 were still alive. Sixty-three of 290 (22%;95% CI, 17-27) of patients in these groups followed up for 10 years were still alive. Together, low-priority patients accounted for 27% of all ICU bed-days and had lower in-hospital mortality (22%) than the high-priority patients (28%). Among nonsurvivors, low-priority admissions had shorter ICU LOS than medium- or high-priority admissions. INTERPRETATION: Current SOFA score or age or severe comorbidity-based ICU pandemic triage protocols exclude patients with a close to 80% hospital survival, a > 30% five-year survival, and 27% of ICU bed-day use. The