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关键词： Hom-Lie algebra   (co)triangular Hom-Hopf algebra   Unified Hom-Yetter-Drinfeld category   Symmetry   Pseudosymmetry  

摘要： In this paper, we discuss properties of the unified Hom-Yetter-Drinfeld categories (HHYD(l))-H-H, where (H, beta) is a Hom-Hopf algebra with bijective antipode S and l is an element of Z (the set of integers). On one hand, we prove the following results about the symmetry and pseudosymmetry of (HHYD(l))-H-H: If (HHYD(l))-H-H is symmetric then H is trivial;(HHYD(l))-H-H is pseudosymmetric if and only if (H, alpha) is commutative and cocommutative;The relations between u-condition of Hom-type and the symmetry of (HHYD(l))-H-H;The (co)representation category of (co)triangular Hom-Hopf algebra is symmetric. On the other hand, we focus on the category (HHYD(0))-H-H. We introduce the notion of (0 degree) unified H-Lie algebra, then show that a Hom-algebra (A, alpha) satisfying additional conditions gives rise to (0 degree) unified H-Lie algebra with suitable bracket product And if (A, alpha) also has two Hom-subalgebras U and X which are (H, beta)-commutative such that A = U + X, then we prove that [A, A][A, A] = 0. (C) 2019 Elsevier B.V. All rights reserved.

关键词： 18D10   57R56  

摘要： The definitions of the nth Gauss sum and the associated nth central charge are introduced for premodular categories C and n. Z. We first derive an expression of the nth Gauss sum of a modular category C, for any integer n coprime to the order of the T-matrix of C, in terms of the first Gauss sum, the global dimension, the twist and their Galois conjugates. As a consequence, we show for these n, the higher Gauss sums are d-numbers and the associated central charges are roots of unity. In particular, if C is the Drinfeld center of a spherical fusion category, then these higher central charges are 1. We obtain another expression of higher Gauss sums for de-equivariantization and local module constructions of appropriate premodular and modular categories. These expressions are then applied to prove theWitt invariance of higher central charges for pseudounitary modular categories.

关键词： Indigenous persistence   colonialism   site recording   dating   California  

摘要： To understand the implications of archaeological site recording practices and associated inventories for studying Indigenous persistence after the arrival of Europeans, we examined the documentary record associated with nearly 900 archaeological sites in Marin County, California. Beginning with the first regional surveys conducted during the early 1900s and continuing into the present, the paper trail created by archaeologists reveals an enduring emphasis on precontact materials to the exclusion of more recent patterns of Indigenous occupation and land use. In assessing sites occupied by Indigenous people from the late sixteenth through the mid-twentieth centuries, we discuss how the use of multiple lines of evidence-including temporally diagnostic artifacts, chronometric dating techniques, and historical documentation-may help illuminate subtle but widespread patterns of Native presence that have been obscured by essentialist assumptions about Indigenous culture change. Our findings further reveal the shortcomings of traditional site recording systems, in which archaeologists typically categorize sites within the prehistoric-protohistoric-historic triad on the basis of commonsense decisions that conflate chronology with identity. Instead, we argue for recording practices that focus specifically on the calendric ages of occupation for any given site.

关键词： attribution theory   linguistic category model   the situational crisis communication theory  

摘要： Through two experiments, this study examines the relationship between linguistic choice and attribution perception in organizational crisis. Experiment 1 demonstrated that abstract (vs. concrete) language in crisis news elicited higher attribution and lower purchase intentions. Experiment two showed that preventable (vs. victim) crisis led to higher usage of abstract language in describing and commenting on the crisis. Also, abstract language use in describing and commenting on the crisis mediates crisis clusters' effect on purchase intentions. Furthermore, attribution of crisis responsibility mediated crisis cluster and in-group/out-group's effects on abstract language use in describing and commenting on the crisis. The findings empirically connect two attribution theory-rooted theories: linguistic category model and the situational crisis communication theory.

关键词： Sugihara monoids   Twist products   Relevant logic   Godel algebras   Relational semantics  

摘要： We give a new Esakia-style duality for the category of Sugihara monoids based on the Davey-Werner natural duality for lattices with involution, and use this duality to greatly simplify a construction due to Galatos-Raftery of Sugihara monoids from certain enrichments of their negative cones. Our method of obtaining this simplification is to transport the functors of the Galatos-Raftery construction across our duality, obtaining a vastly more transparent presentation on duals. Because our duality extends Dunn's relational semantics for the logic R-mingle to a categorical equivalence, this also explains the Dunn semantics and its relationship with the more usual Routley-Meyer semantics for relevant logics. (C) 2019 Elsevier B.V. All rights reserved.

关键词： 18A25   18D05   18G55   55P15   55U10   55U35 (primary)   18G30   55P20   55P35 (secondary)  

摘要： We prove a generalization of Quillen's Theorem B to strict infinity-categories. More generally, we show that under similar hypothesis as for Theorem B, the comma construction for strict infinity-categories, that we introduced with Maltsiniotis in a previous paper, is the homotopy pullback with respect to Thomason equivalences. We give several applications of these results including the construction of new models for certain Eilenberg-Mac Lane spaces.

关键词： Glucosamine   Chitin   Mycelium   Fermentation   Enzymatic catalysis   High-end product  

摘要： Glucosamine (GlcN) is an amine sugar, in which a hydroxyl group of glucose is replaced with an amino group. It is an important part of the polysaccharides chitin and chitosan and is highly hydrophilic. It is also an important compound required for the formation of cartilage cells and represents one of the elementary units of the cartilage matrix and joint fluid. GlcN has been widely used in food, cosmetics, health care, and pharmaceutical industries. This paper fully addresses the categories and biomanufacturing methods of GlcN, including its production by fermentation with wild-type as well as engineered microorganisms and enzymatic catalysis with a series of chitinolytic enzymes. However, GlcN is usually produced from glucose by fermentation in a coupled manner with N-acetylglucosamine (GlcNAc). Enzymatic catalysis is thus a specific pathway for production of GlcN where chitin can be directly hydrolyzed to GlcN. In industry, GlcN produced with fungal mycelium as raw materials (plant GlcN) is thought as a high-end product because of vegetarian and non-transgenosis. In our opinion, more studies should be performed in order to develop a competitive enzymatic pathway using Aspergillus niger mycelium for the preparation of high-end GlcN.

关键词： Linear orderings   Hyperarithmetically categorical   Computable ordinals   Effective structure theory  

摘要： We prove that for every computable limit ordinal alpha there exists a computable linear ordering A which is Delta(0)(alpha)-categorical and alpha is smallest such, but nonetheless for every isomorphic computable copy B of A there exists a beta < alpha such that A congruent to(Delta beta 0) B. This answers a question left open in the earlier work of Downey, Igusa, and Melnikov. We also show that such examples can be found among ordered abelian groups and real-closed fields. (C) 2019 Published by Elsevier B.V.

关键词： Prostate cancer   Magnetic resonance imaging   Nomogram  

摘要： Objectives To evaluate whether low PI-RADS v2 assessment categories are effective at excluding extraprostatic extension (EPE) of prostate cancer (>= pT3a PCa). Methods The local institutional ethics committee approved this retrospective analysis of 301 consecutive PCa patients. Patients were classified as low- or intermediate/high-risk based on clinical parameters and underwent pre-surgical multiparametric magnetic resonance imaging. A PI-RADS v2 assessment category and ESUR EPE score were assigned for each lesion by two readers working in consensus. Histopathologic analysis of the whole-mount radical prostatectomy specimen was the reference standard. Univariate and multivariate analyses were performed to evaluate the association of PI-RADS v2 assessment category with final histology >= pT3a PCa. Results For a PI-RADS v2 assessment category threshold of 3, the overall performance for ruling out (sensitivity, negative predictive value, negative likelihood ratio) >= pT3a PCa was 99%/98%/0.04 and was similar in both the low-risk (96%/97%/0.12;N = 137) and the intermediate/high-risk groups (100%/100%/0.0;N = 164). In univariate analysis, all clinical and tumor characteristics except age were significantly associated with >= pT3a PCa. In multivariate analysis, PI-RADS v2 assessment categories <= 3 had a protective effect relative to categories 4 and 5. The inclusion of ESUR EPE score improved the AUC of >= pT3a PCa prediction (from 0.73 to 0.86, p = 0.04 in the overall cohort). The impact of PI-RADS v2 assessment category is reflected in a nomogram derived on the basis of our cohort. Conclusions In our cohort, low PI-RADS v2 assessment categories of 3 or less confidently ruled out the presence of >= pT3a PCa irrespective of clinical risk group.

关键词： Aichi target 11   Ley de Rompientes   marine conservation   marine protected areas   OECMs   surf breaks   surfing   TURFs   World Surfing Reserves  

摘要： The expansion of surfing as a multibillion-dollar industry and sport has, on the one hand, increased awareness about threats posed to marine and coastal environments, but has also brought growing acknowledgement of the environmental, cultural and economic value that surfing provides. This has been accompanied by a growing movement of surfers and related stakeholders (e.g. communities and manufacturers that rely on the surf tourism and industry for income) that seek to protect surf breaks. This paper argues that certain emblematic surf breaks should be protected not only for their value to surfers, but also for the ecosystem services they provide and other benefits for marine conservation. Through a series of case studies from Peru, Chile and the USA, the paper discusses how, in areas where there is significant biodiversity or iconic seascapes, surf breaks can be integrated with marine conservation. Suggestions are given regarding the International Union for Conservation of Nature categories of protected areas that are most appropriate for such cases. The paper also explores how, in certain cases, several existing surf-break protection mechanisms could qualify as other effective area-based conservation measures, including Chile's proposed TURF-surf model, the international World Surfing Reserves, and Peru's Ley de Rompientes. In this way, certain surf-break protection mechanisms could help contribute to countries' progress towards achieving the Convention on Biological Diversity's Aichi Target 11. Overall benefits of marine conservation groups and surfers joining forces are discussed, including how this can help reduce negative impacts of the sport on natural ecosystems.