9,759 research outputs found

    Constraints on the duality relation from ACT cluster data

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    The cosmic distance-duality relation (CDDR), dL(z)(1+z)2/dA(z)=ηd_L(z) (1 + z)^{2}/d_{A}(z) = \eta, where η=1\eta = 1 and dL(z)d_L(z) and dA(z)d_A(z) are, respectively, the luminosity and the angular diameter distances, holds as long as the number of photons is conserved and gravity is described by a metric theory. Testing such hypotheses is, therefore, an important task for both cosmology and fundamental physics. In this paper we use 91 measurements of the gas mass fraction of galaxy clusters recently reported by the Atacama Cosmology Telescope (ACT) survey along with type Ia supernovae observations of the Union2.1 compilation to probe a possible deviation from the value η=1\eta = 1. Although in agreement with the standard hyphothesis, we find that this combination of data tends to favor negative values of η\eta which might be associated with some physical processes increasing the number of photons and modifying the above relation to dL<(1+z)2dAd_L < (1+z)^2d_A.Comment: 4 pages, 2 figures, 2 table

    Generalized Chaplygin gas with α=0\alpha = 0 and the ΛCDM\Lambda CDM cosmological model

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    The generalized Chaplygin gas model is characterized by the equation of state p=−Aραp = - \frac{A}{\rho^\alpha}. It is generally stated that the case α=0\alpha = 0 is equivalent to a model with cosmological constant and dust (ΛCDM\Lambda CDM). In this work we show that, if this is true for the background equations, this is not true for the perturbation equations. Hence, the mass spectrum predicted for both models may differ.Comment: Latex file, 4 pages, 2 figures in eps forma

    Interoperability and Standards: The Way for Innovative Design in Networked Working Environments

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    Organised by: Cranfield UniversityIn today’s networked economy, strategic business partnerships and outsourcing has become the dominant paradigm where companies focus on core competencies and skills, as creative design, manufacturing, or selling. However, achieving seamless interoperability is an ongoing challenge these networks are facing, due to their distributed and heterogeneous nature. Part of the solution relies on adoption of standards for design and product data representation, but for sectors predominantly characterized by SMEs, such as the furniture sector, implementations need to be tailored to reduce costs. This paper recommends a set of best practices for the fast adoption of the ISO funStep standard modules and presents a framework that enables the usage of visualization data as a way to reduce costs in manufacturing and electronic catalogue design.Mori Seiki – The Machine Tool Compan

    The Safe-Port project: an approach to port surveillance and protection

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    SAFE-PORT is a recently started project addressing the complex issue of determining the best configurations of resources for harbour and port surveillance and protection. More specifically, the main goal is to find, for any given scenario, an adequate set of configuration solutions — i.e., number and type of sensors and equipments, their locations and operating modes, the corresponding personnel and other support resources — that maximize protection over a specific area. The project includes research and development of sensors models, novel algorithms for optimization and decision support, and a computer-based decision support system (DSS) to assist decision makers in that task. It includes also the development of a simulation environment for modelling relevant aspects of the scenario (including sensors used for surveillance, platforms, threats and the environment), capable to incorporate data from field-trials, used to test and validate solutions proposed by the DSS. Test cases will consider the use of intelligent agents to model the behaviour of threats and of NATO forces in a realistic way, following experts’ definitions and parameters

    Neuropsychiatric Systemic Lupus Erythematosus Involvement: Towards a Tailored Approach to Our Patients?

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    Neuropsychiatric involvement in systemic lupus erythematosus (NPSLE) is a complex condition that remains poorly understood, and includes heterogeneous manifestations involving both the central and peripheral nervous system, with disabling effects. There are several models to improve NPSLE diagnosis when a neurological syndrome is present. In the last couple of years, the growing knowledge of the role of cytokines and antibodies in NPSLE, as well as the development of new functional imaging techniques, has brought some insights into the physiopathology of the disease, but their validation for clinical use remains undetermined. Furthermore, besides the classic clinical approach, a new tool for screening the 19 NPSLE syndromes has also been developed. Regarding NPSLE therapeutics, there is still no evidence-based treatment approach, but some data support the safety of biological medication when classic treatment fails. Despite the tendency to reclassify SLE patients in clinical and immunological subsets, we hope that these data will inspire medical professionals to approach NPSLE in a manner more tailored to the individual patient.info:eu-repo/semantics/publishedVersio

    Cultivo sustentĂĄvel de feijĂŁo caupi (Vigna unguiculata (L.) Walp.) em ecossistema de vĂĄrzea amazĂŽnica.

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    Este trabalho objetivou avaliar 20 genótipos de feijão caupi em ecossistema de vårzea amazÎnica situada à margem do Rio SolimÔes, nas condiçÔes edafoclimåticas de Iranduba-AM
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