5,302 research outputs found

    Algebras of Toeplitz operators on the n-dimensional unit ball

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    We study CC^*-algebras generated by Toeplitz operators acting on the standard weighted Bergman space Aλ2(Bn)\mathcal{A}_{\lambda}^2(\mathbb{B}^n) over the unit ball Bn\mathbb{B}^n in Cn\mathbb{C}^n. The symbols facf_{ac} of generating operators are assumed to be of a certain product type, see (\ref{Introduction_form_of_the_symbol}). By choosing aa and cc in different function algebras Sa\mathcal{S}_a and Sc\mathcal{S}_c over lower dimensional unit balls B\mathbb{B}^{\ell} and Bn\mathbb{B}^{n-\ell}, respectively, and by assuming the invariance of aSaa\in \mathcal{S}_a under some torus action we obtain CC^*-algebras Tλ(Sa,Sc)\boldsymbol{\mathcal{T}}_{\lambda}(\mathcal{S}_a, \mathcal{S}_c) whose structural properties can be described. In the case of kk-quasi-radial functions Sa\mathcal{S}_a and bounded uniformly continuous or vanishing oscillation symbols Sc\mathcal{S}_c we describe the structure of elements from the algebra Tλ(Sa,Sc)\boldsymbol{\mathcal{T}}_{\lambda}(\mathcal{S}_a, \mathcal{S}_c), derive a list of irreducible representations of Tλ(Sa,Sc)\boldsymbol{\mathcal{T}}_{\lambda}(\mathcal{S}_a, \mathcal{S}_c), and prove completeness of this list in some cases. Some of these representations originate from a ``quantization effect'', induced by the representation of Aλ2(Bn)\mathcal{A}_{\lambda}^2(\mathbb{B}^n) as the direct sum of Bergman spaces over a lower dimensional unit ball with growing weight parameter. As an application we derive the essential spectrum and index formulas for matrix-valued operators

    The relevance of outsourcing and leagile strategies in performance optimization of an integrated process planning and scheduling

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    Over the past few years growing global competition has forced the manufacturing industries to upgrade their old production strategies with the modern day approaches. As a result, recent interest has been developed towards finding an appropriate policy that could enable them to compete with others, and facilitate them to emerge as a market winner. Keeping in mind the abovementioned facts, in this paper the authors have proposed an integrated process planning and scheduling model inheriting the salient features of outsourcing, and leagile principles to compete in the existing market scenario. The paper also proposes a model based on leagile principles, where the integrated planning management has been practiced. In the present work a scheduling problem has been considered and overall minimization of makespan has been aimed. The paper shows the relevance of both the strategies in performance enhancement of the industries, in terms of their reduced makespan. The authors have also proposed a new hybrid Enhanced Swift Converging Simulated Annealing (ESCSA) algorithm, to solve the complex real-time scheduling problems. The proposed algorithm inherits the prominent features of the Genetic Algorithm (GA), Simulated Annealing (SA), and the Fuzzy Logic Controller (FLC). The ESCSA algorithm reduces the makespan significantly in less computational time and number of iterations. The efficacy of the proposed algorithm has been shown by comparing the results with GA, SA, Tabu, and hybrid Tabu-SA optimization methods

    A Declarative Framework for Specifying and Enforcing Purpose-aware Policies

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    Purpose is crucial for privacy protection as it makes users confident that their personal data are processed as intended. Available proposals for the specification and enforcement of purpose-aware policies are unsatisfactory for their ambiguous semantics of purposes and/or lack of support to the run-time enforcement of policies. In this paper, we propose a declarative framework based on a first-order temporal logic that allows us to give a precise semantics to purpose-aware policies and to reuse algorithms for the design of a run-time monitor enforcing purpose-aware policies. We also show the complexity of the generation and use of the monitor which, to the best of our knowledge, is the first such a result in literature on purpose-aware policies.Comment: Extended version of the paper accepted at the 11th International Workshop on Security and Trust Management (STM 2015

    Large CP Violation in B_s Meson Mixing with EDM constraint in Supersymmetry

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    Motivated by the recent measurement of the like-sign dimuon charge asymmetry, we investigate anomalous CP violation in the B_s- bar{B}_s mixing within the supersymmetry. We show that when gluino diagrams dominate supersymmetry contributions, it is very difficult to realize a large B_s- bar{B}_s mixing phase under the constraint from electric dipole moments barring cancellations. This constraint can be ameliorated by supposing superparticles decoupled. In this limit, we find that it is possible to achieve the large CP asymmetry, and the branching ratio of B_s -> mu^+ mu^- tends to become sizable.Comment: 20 pages, 5 figure

    Metastatic primary adenocarcinoma of the bladder in a twenty-five years old woman

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    Primary adenocarcinoma of the bladder is a rare tumor. The classification between primary vesical and urachal is debated. We present the case of a young female who presented clinicopathological features of a metastatic urachal adenocarcinoma, but the histological result revealed primary adenocarcinoma of the bladder contrary to expectancy. To the best of our knowledge this is the first reported case of a metastatic adenocarcinoma of the bladder in a 25 years old female. This case emphasizes the challenge for urologists to recognize and manage this aggressive tumor in the setting described

    Clostridium difficile ribotypes in Austria: a multicenter, hospital-based survey

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    A prospective, noninterventional survey was conducted among Clostridium difficile positive patients identified in the time period of July until October 2012 in 18 hospitals distributed across all nine Austrian provinces. Participating hospitals were asked to send stool samples or isolates from ten successive patients with C.difficile infection to the National Clostridium difficile Reference Laboratory at the Austrian Agency for Health and Food Safety for PCR-ribotyping and in vitro susceptibility testing. A total of 171 eligible patients were identified, including 73 patients with toxin-positive stool specimens and 98 patients from which C. difficile isolates were provided. Of the 159 patients with known age, 127 (74.3 %) were 65 years or older, the median age was 76 years (range: 9–97 years), and the male to female ratio 2.2. Among these patients, 73 % had health care-associated and 20 % community-acquired C. difficile infection (indeterminable 7 %). The all-cause, 30-day mortality was 8.8 % (15/171). Stool samples yielded 46 different PCR-ribotypes, of which ribotypes 027 (20 %), 014 (15.8 %), 053 (10.5 %), 078 (5.3 %), and 002 (4.7 %) were the five most prevalent. Ribotype 027 was found only in the provinces Vienna, Burgenland, and Lower Austria. Severe outcome of C. difficile infection was found to be associated with ribotype 053 (prevalence ratio: 3.04; 95 % CI: 1.24, 7.44), not with the so-called hypervirulent ribotypes 027 and 078. All 027 and 053 isolates exhibited in vitro resistance against moxifloxacin. Fluoroquinolone use in the health care setting must be considered as a factor favoring the spread of these fluoroquinolone resistant C. difficile clones

    Exploring Protein-Protein Interactions as Drug Targets for Anti-cancer Therapy with In Silico Workflows

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    We describe a computational protocol to aid the design of small molecule and peptide drugs that target protein-protein interactions, particularly for anti-cancer therapy. To achieve this goal, we explore multiple strategies, including finding binding hot spots, incorporating chemical similarity and bioactivity data, and sampling similar binding sites from homologous protein complexes. We demonstrate how to combine existing interdisciplinary resources with examples of semi-automated workflows. Finally, we discuss several major problems, including the occurrence of drug-resistant mutations, drug promiscuity, and the design of dual-effect inhibitors.Fil: Goncearenco, Alexander. National Institutes of Health; Estados UnidosFil: Li, Minghui. Soochow University; China. National Institutes of Health; Estados UnidosFil: Simonetti, Franco Lucio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Shoemaker, Benjamin A. National Institutes of Health; Estados UnidosFil: Panchenko, Anna R. National Institutes of Health; Estados Unido

    Spatially Explicit Data: Stewardship and Ethical Challenges in Science

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    Scholarly communication is at an unprecedented turning point created in part by the increasing saliency of data stewardship and data sharing. Formal data management plans represent a new emphasis in research, enabling access to data at higher volumes and more quickly, and the potential for replication and augmentation of existing research. Data sharing has recently transformed the practice, scope, content, and applicability of research in several disciplines, in particular in relation to spatially specific data. This lends exciting potentiality, but the most effective ways in which to implement such changes, particularly for disciplines involving human subjects and other sensitive information, demand consideration. Data management plans, stewardship, and sharing, impart distinctive technical, sociological, and ethical challenges that remain to be adequately identified and remedied. Here, we consider these and propose potential solutions for their amelioration
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