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关键词： Package color   Categorization   Perceived typicality   Attitude  

摘要： Despite the growing amount of research on different aspects of product package design, there is lack of empirical evidence with regard to how package color perceptions may influence consumer preferences. Based on categorization theory, the present paper explores responses to package colors that conform or do not conform to product category color norms. Results of two experiments show that atypical package colors implicate negative consequences to the brand. Findings indicate that perceived package color atypicality increases consumers' skepticism and, contrary to expectations, decreases interest. These affective reactions negatively influence consumers' product attitude which subsequently translates into lower purchase intention. The results provide important insights for theory and practice.

关键词： pain   pain management   pain score   inference  

摘要： A noncommutative deformation of a quadric surface is usually described by a three-dimensional cubic Artin-Schelter regular algebra. In this paper we show that for such an algebra its bounded derived category embeds into the bounded derived category of a commutative deformation of the Hilbert scheme of two points on the quadric. This is the second example in support of a conjecture by Orlov. Based on this example we formulate an infinitesimal version of the conjecture and provide some evidence in the case of smooth projective surfaces.

关键词： Thyroid neoplasms   Diagnostic imaging   Ultrasonography   Systematic review   Meta-analysis  

摘要： Objectives To determine the accuracies of the American College of Radiology (ACR)-thyroid imaging reporting and data systems (TIRADS), Korean (K)-TIRADS, and European (EU)-TIRADS for diagnosing malignancy in thyroid nodules. Methods Original studies reporting the diagnostic accuracy of TIRADS for determining malignancy on ultrasound were identified in MEDLINE and EMBASE up to June 23, 2019. The meta-analytic summary sensitivity and specificity were obtained for TIRADS category 5 (TR-5) and category 4 or 5 (TR-4/5), using a bivariate random effects model. To explore study heterogeneity, meta-regression analyses were performed. Results Of the 34 eligible articles (37,585 nodules), 25 used ACR-TIRADS, 12 used K-TIRADS, and seven used EU-TIRADS. For TR-5, the meta-analytic sensitivity was highest for EU-TIRADS (78% [95% confidence interval, 64-88%]), followed by ACR-TIRADS (70% [61-79%]) and K-TIRADS (64% [58-70%]), although the differences were not significant. K-TIRADS showed the highest meta-analytic specificity (93% [91-95%]), which was similar to ACR-TIRADS (89% [85-92%]) and EU-TIRADS (89% [77-95%]). For TR-4/5, all three TIRADS systems had sensitivities higher than 90%. K-TIRADS had the highest specificity (61% [50-72%]), followed by ACR-TIRADS (49% [43-56%]) and EU-TIRADS (48% [35-62%]), although the differences were not significant. Considerable threshold effects were noted with ACR- and K-TIRADS (p <= 0.01), with subject enrollment, country of origin, experience level of reviewer, number of patients, and clarity of blinding in review being the main causes of heterogeneity (p <= 0.05). Conclusions There was no significant difference among these three international TIRADS, but the trend toward higher sensitivity with EU-TIRADS and higher specificity with K-TIRADS.

关键词： Matroid   Matroid strong maps   Matroid-minor Hopf algebra   Hall algebra   Proto-exact category   K-theory  

摘要： This paper examines the category Mat(circle) of pointed matroids and strong maps from the point of view of Hall algebras. We show that Mat(circle) has the structure of a finitary proto-exact category - a non-additive generalization of exact category due to Dyckerhoff-Kapranov. We define the algebraic K-theory K-*(Mat(circle)) of Mat(circle) via the Waldhausen construction, and show that it is non-trivial, by exhibiting injections pi(s)(n) (S) hooked right arrow K-n (Mat(circle)) from the stable homotopy groups of spheres for all n. Finally, we show that the Hall algebra of Mat(circle) is a Hopf algebra dual to Schmitt's matroid-minor Hopf algebra.

关键词： Lattices   Semilattices   Duality   Filters  

摘要： The main aim of this article is to develop a categorical duality between the category of semilattices with homomorphisms and a category of certain topological spaces with certain morphisms. The principal tool to achieve this goal is the notion of irreducible filter. Then, we apply this dual equivalence to obtain a topological duality for the category of bounded lattices and lattice homomorphism. We show that our topological dualities for semilattices and lattices are natural generalizations of the duality developed by Stone for distributive lattices through spectral spaces. Finally, we obtain directly the categorical equivalence between our topological spaces and those presented for Moshier and Jipsen (Algebra Univers 71(2):109-126, 2014).

摘要： Computational protein-protein docking is one of the most intensively studied topics in structural bioinformatics. The field has made substantial progress through over three decades of development. The development began with methods for rigid-body docking of two proteins, which have now been extended in different directions to cover the various macromolecular interactions observed in a cell. Here, we overview the recent developments of the variations of docking methods, including multiple protein docking, peptide-protein docking, and disordered protein docking methods.

关键词： Front-of-package   Health logos   Warnings   Nutrition information   FOP  

摘要： Front-of-package (FOP) nutrition labelling schemes use different framing to highlight nutrient content and promote healthier food choices. Health logos and nutritional warnings can be positioned on opposite sides of a continuous that goes from highlighting healthful products (gain-frame) to highlight unhealthful products (loss-frame), respectively. The aim of the present work was to evaluate the impact of health logos and nutritional warnings on consumers' choice of products with lower sugar content, and the impact of the two FOP nutrition labelling schemes on consumers' associations with sugar. An online study with 1232 people was carried out. Participants were randomly assigned to three experimental conditions: control (no information), health logos and nutritional warnings. They were presented with a series of three packages of different product categories featuring the corresponding information about sugar content and they had to indicate the product they would buy. After completing the choice tasks, they had to complete a word association task about sugar. Results confirmed that the inclusion of FOP nutrition labelling schemes containing information about sugar content encouraged consumers to select the product with lower sugar content. A larger proportion of participants selected the product with the lowest sugar content when packages featured nutritional warnings compared to when they featured health logos. Results from the word association task showed that nutritional warnings made the negative health effects of sugar more salient on consumers' mind. These results suggest that FOP nutrition labelling schemes based on a loss-frame to sugar content may be more efficient at encouraging healthier food choices than gain-frame schemes.

关键词： Latent class model   Local independence assumption   Health insurance   Healthcare utilization   Categorical health data  

摘要： Latent class models are now widely applied in health economics to analyse heterogeneity in multiple outcomes generated by subgroups of individuals who vary in unobservable characteristics, such as genetic information or latent traits. These models rely on the underlying assumption that associations between observed outcomes are due to their relationship to underlying subgroups, captured in these models by conditioning on a set of latent classes. This implies that outcomes are locally independent within a class. Local independence assumption, however, is sometimes violated in practical applications when there is uncaptured unobserved heterogeneity resulting in residual associations between classes. While several approaches have been proposed in the case of binary and continuous outcomes, little attention has been directed to the case of multiple ordered categorical outcome variables often used in health economics. In this paper, we develop an approach to test for the violation of the local independence assumption in the case of multiple ordered categorical outcomes. The approach provides a detailed decomposition of identified residual association by allowing it to vary across latent classes and between levels of the ordered categorical outcomes within a class. We show how this level of decomposition is important in the case of ordered categorical outcomes. We illustrate our approach in the context of health insurance and healthcare utilization in the US Medigap market.