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关键词： Diagonals-parameter symmetry   Local odds ratio   Sub-table   Uniform association  

摘要： This study proposes original symmetry models with a structure wherein the local odds ratios increase exponentially as the row number of the square contingency table increases in each sub-table. The proposed models provide a better fit than the existing models. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Derived categories   Semi-orthogonal decompositions   Deligne-Mumford Stacks  

摘要： Suppose f , g are homogeneous polynomials of degree d defining smooth hypersurfaces X-f = V(f) subset of Pm-1 and X-g = V(g) subset of Pn-1. Then the sum of f and g defines a smooth hypersurface X = V(f circle plus g) subset of Pm+n-1 with an action of mu(d) scaling the g variables. Motivated by the work of Orlov, we construct a semi-orthogonal decomposition of the derived category of coherent sheaves on [X/mu(d)] provided d >= max{m, n}. Published by Elsevier B.V.

关键词： Cartesian differential categories   Exponential functions   Differential exponential maps   Differential exponential rigs  

摘要： In this paper, we introduce differential exponential maps in Cartesian differential categories, which generalizes the exponential function ex from classical differential calculus. A differential exponential map is an endomorphism which is compatible with the differential combinator in such a way that generalizations of e(0) = 1, e(x+y) = e(x)e(y), and partial derivative e(x)/partial derivative x = e(x) all hold. Every differential exponential map induces a commutative rig, which we call a differential exponential rig, and conversely, every differential exponential rig induces a differential exponential map. In particular, differential exponential maps can be defined without the need of limits, converging power series, or unique solutions of certain differential equations-which most Cartesian differential categories do not necessarily have. That said, we do explain how every differential exponential map does provide solutions to certain differential equations, and conversely how in the presence of unique solutions, one can derivative a differential exponential map. Examples of differential exponential maps in the Cartesian differential category of real smooth functions include the exponential function, the complex exponential function, the split complex exponential function, and the dual numbers exponential function. As another source of interesting examples, we also study differential exponential maps in the coKleisli category of a differential category.

关键词： Categories   Logoi   Contextuality   Kochen-Specker theorem   Intensive valuation  

摘要： In this paper we present a new categorical approach which attempts to provide an original understanding of QM. Our logos categorical approach attempts to consider the main features of the quantum formalism as the standpoint to develop a conceptual representation that explains what the theory is really talking about -rather than as problems that need to be bypassed in order to allow a restoration of a classical "common sense" understanding of what there is. In particular, we discuss a solution to Kochen-Specker contextuality through the generalization of the meaning of global valuation. This idea has been already addressed by the so called topos approach to QM -originally proposed by Isham, Butterfiled and Doring- in terms of sieve-valued valuations. The logos approach to QM presents a different solution in terms of the notion of intensive valuation. This new solution stresses an ontological (rather than epistemic) reading of the quantum formalism and the need to restore an objective (rather than classical) conceptual representation and understanding of quantum physical reality.

摘要： Background: Health authorities can influence citizens in subtle ways that render them more likely to participate in cancer screening programmes, and thereby possibly increase the beneficial effects. If the influences become too severe, the citizens' ability to make a personal choice may be lost on the way. The purpose of this analysis was to identify and categorize the influences while questioning whether they still permit the citizens to make their own choices regarding participation. Methods: A two-stringed approach was used to obtain empirical examples of systematic influences that aim to raise participation rates in cancer screening programmes: First, a systematic literature search was conducted on three databases. Second, relevant experts were contacted via internationally based e-mail lists and asked for examples of systematic influences in cancer screening. The present analysis was based on direct, conventional content analysis to address different categories of systematic influences. Results: The literature search yielded 19 included articles and the expert inquiry yielded 11 empirical examples of which content analysis of the empirical examples generated six major categories of systematic influence: (i) misleading presentation of statistics, (ii) misrepresentation of harms vs. benefits, (iii) opt-out systems, (iv) recommendation of participation, (v) fear appeals and (vi) influencing the general practitioners and other healthcare professionals. Conclusion: The six categories of identified influences work through psychological biases and personal costs and are still in widely use. The use of these types of influence remains ethically questionable in cancer screening programmes since they might compromise informed decision making.

关键词： PAH   Pollution   Endocrine disruption   Gut bacteria   Land cover categories   Urban/rural gradient  

摘要： There is evidence that polycyclic aromatic hydrocarbons (PAHs) and human gut microbiota are associated with the modulation of endocrine signaling pathways. Independently, studies have found associations between air pollution, land cover and commensal microbiota. We are the first to estimate the interaction between land cover categories associated with air pollution or purification, PAH levels and endocrine signaling predicted from gut metagenome among urban and rural populations. The study participants were elderly people (65-79 years);30 lived in rural and 32 in urban areas. Semi-Permeable Membrane devices were utilized to measure air PAH concentrations as they simulate the process of bioconcentration in the fatty tissues. Land cover categories were estimated using CORINE database and geographic information system. Functional orthologues for peroxisome proliferator-activated receptor (PPAR) pathway in endocrine system were analyzed from gut bacterial metagenome with Kyoto Encyclopaedia of Genes and Genomes. High coverage of broad-leaved and mixed forests around the homes were associated with decreased PAH levels in ambient air, while gut functional orthologues for PPAR pathway increased along with these forest types. The difference between urban and rural PAH concentrations was not notable. However, some rural measurements were higher than the urban average, which was due to the use of heavy equipment on active farms. The provision of air purification by forests might be an important determining factor in the context of endocrine disruption potential of PAHs. Particularly broad-leaved forests around homes may reduce PAH levels in ambient air and balance pollution-induced disturbances within commensal gut microbiota. (C) 2020 The Author(s). Published by Elsevier Ltd.

摘要： Applying Popa's orthogonality method to a new class of groups, we construct amenable group factors that are prime and have no infinite-dimensional regular abelian *-subalgebras. By adjusting Farah-Katsura's solution of Dixmier's problem to the von Neumann algebra setting, we obtain the 1st examples of prime approximately finite-dimensional factors and tensorially prime simple AF-algebras. Our results are proved in Zermelo-Fraenkel set theory with the axiom of choice (ZFC), thus in particular answering questions asked by Farah-Hathaway-Katsura-Tikuisis. We also directly determine central sequences of certain crossed products. This concludes the failure of the Kirchberg O-infinity-absorption theorem in the non-separable setting.

关键词： 14F42 (primary)   18D10   18E30   18G99   19E15   14L17 (secondary)  

摘要： We explain why every non-trivial exact tensor functor on the triangulated category of mixed motives over a fieldFhas zero kernel, if one assumes 'all' motivic conjectures. In other words, every non-zero motive generates the whole category up to the tensor triangulated structure. Under the same assumptions, we also give a complete classification of triangulated etale motives overFwith integral coefficients, up to the tensor triangulated structure, in terms of the characteristic and the orderings ofF.

关键词： EMG   LSGS   AB-k-means   Hand grasps   Feature extraction  

摘要： Electromyogram (EMG) signals have had a great impact on many applications, including prosthetic or rehabilitation devices, human-machine interactions, clinical and biomedical areas. In recent years, EMG signals have been used as a popular tool to generate device control commands for rehabilitation equipment, such as robotic prostheses. This intention of this study was to design an EMG signal-based expert model for hand-grasp classification that could enhance prosthetic hand movements for people with disabilities. The study, thus, aimed to introduce an innovative framework for recognising hand movements using EMG signals. The proposed framework consists of logarithmic spectrogram-based graph signal (LSGS), AdaBoost k-means (AB-k-means) and an ensemble of feature selection (FS) techniques. First, the LSGS model is applied to analyse and extract the desirable features from EMG signals. Then, to assist in selecting the most influential features, an ensemble FS is added to the design. Finally, in the classification phase, a novel classification model, named AB-k-means, is developed to classify the selected EMG features into different hand grasps. The proposed hybrid model, LSGS-based scheme is evaluated with a publicly available EMG hand movement dataset from the UCI repository. Using the same dataset, the LSGS-AB-k-means design model is also benchmarked with several classifications including the state-of-the-art algorithms. The results demonstrate that the proposed model achieves a high classification rate and demonstrates superior results compared to several previous research works. This study, therefore, establishes that the proposed model can accurately classify EMG hand grasps and can be implemented as a control unit with low cost and a high classification rate.

关键词： Exact categories   Monomorphism category   Functor category   Bounded derived category   Singularity category  

摘要： Let X be a contravariantly finite resolving subcategory of mod-Lambda, the category of finitely generated right.-modules. We associate to X the subcategory S-X (Lambda) of the morphism category H(Lambda) consisting of all monomorphisms ( A ->(f) B) with A, B and Cok f in X. Since SX (Lambda) is closed under extensions it inherits naturally an exact structure from H(Lambda). We will define two other different exact structures other than the canonical one on SX (Lambda), and completely classify the indecomposable projective (resp. injective) objects in the corresponding exact categories. Enhancing SX (Lambda) with the new exact structure provides a framework to construct a triangle functor. Let mod-X denote the category of finitely presented functors over the stable category X. We then use the triangle functor to show a triangle equivalence between the bounded derived category D-b(mod-X) and a Verdier quotient of the bounded derived category of the associated exact category on SX (Lambda). Similar consideration is also given for the singularity category of mod-X.