10,221 research outputs found

    Majorization and dynamics of continuous distributions

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    In this work we show how the concept of majorization in continuous distributions can be employed to characterize chaotic, diffusive and quantum dynamics. The key point lies in that majorization allows to define an intuitive arrow of time, within a continuous dynamics, along with an associated majorized Second Law which implies the standard Second Law of thermodynamics but not viceversa. Moreover, mixing dynamics, generalized Fokker-Planck equations and quantum evolutions are explored as majorized ordered chains along the time evolution, being the stationary states the infimum elements

    Flywheel -" A Bateria Electromecânica"..

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    Desde sempre, o homem necessitou de fontes energéticas. Uma vez que essas fontes não estão sempre disponíveis, existe a necessidade de armazenar a energia para utilização posterior. Isso passa-se com os seres vivos que, alimentando-se, conservam a energia dos alimentos sob a forma de compostos químicos no próprio organismo. Com o desenvolvimento da civilização tornou-se óbvio o armazenamento de várias formas de energia. No caso de um painel solar, só se produz energia durante as horas do dia. Mas o homem também vive de noite, necessitando também de energia eléctrica. Torna-se então clara a necessidade de armazenar a energia produzida durante o dia, muitas vezes em excesso, pois nem sequer é utilizada

    A Fauna de Morcegos Fósseis como Ferramenta na Caracterização de Paleoambientes Quaternários.

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    This study proposes to reconstruct the paleoenvironment from Quaternary sites of the caves in the sertão baiano and Lagoa Santa region during the Pleistocene. The paleofauna of bats from these sites were compared to the extant fauna of 25 localities, representing most important Neotropical biome. This study was possible because all bat fossil species from both sites were elements of the extant Neotropical fauna, excepting Desmodus draculae. Because bats are considered goodenvironmental definers, the association of extant and fossil fauna permits the recognition of similar environments. The similarity between faunas was analyzed by Jaccard index with a posterior grouping analysis by UPGMA. The paleofauna of Lagoa Santa matched to Caatinga fauna, suggesting a dry and open environment adjacent to the Lagoa Santa cavesduring the Pleistocene. The paleofauna of sertão baiano caves matched to neither of the analyzed faunas. Most authorssuggest that fossil record of the sertão baiano caves represents a faunal mixture. The dissimilarity between the paleofaunaof bats from the sertão baiano caves and the other analyzed faunas resulted of this study is in agreement to the argumentof a faunal mixture represented by the former

    Actas da 10ª Conferência sobre Redes de Computadores

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    Universidade do MinhoCCTCCentro AlgoritmiCisco SystemsIEEE Portugal Sectio

    A new approach on communications architectures for intelligent transportation systems

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    A Vehicular Adhoc Network (VANET) is a generic communications conceptualization that can be applied to Intelligent Transportation Systems (ITS) and its main goal is to allow exchange of information between moving vehicles, fixed infrastructures, pedestrians with personal devices, and all other electronic devices able to connect to a VANET environment. Information exchange between different stakeholders brings a relevant potential to the development of applications to help users in different areas such as traffic safety and efficiency, infotainment and personal comfort. However, due to the expected heterogeneity (different processing power and storage capabilities, communications technologies and mobility patterns) and large scale on the number of devices involved, application interoperability in VANET contexts can be a challenging problem. Non-agnostic standard communications architectures for ITS systems have some deploying limitations and lack important specific implementation details. This paper presents an agnostic VANET architecture (it permits the use of several communication technologies in an open and modular framework), which is an adaption of present standards approach, to be deployed on ITS systems as a mean to overcome their main limitations. (C) 2017 The Authors. Published by Elsevier B.V.This work has been sponsored by the Portugal Incentive System for Research and Technological Development. Project in co-promotion no 002797/2015 (INNOVCAR 2015-2018), and also by COMPETE: POCI-01-0145-FEDER-007043 and FCT - Fundação para a Ciência e Tecnologia within the Project Scope: UID/CEC/00319/2013

    Synthesis and biological evaluation of new salicylate macrolactones from anacardic acids

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    No âmbito de uma linha de pesquisa que visa a obtenção de novas substâncias bioativas, a partir de lipídeos fenólicos não-isoprenóides de Anacardium occidentale, descrevemos a síntese e avaliação citotóxica de novas macrolactonas salicílicas, preparadas a partir da mistura de ácidos anacárdicos, principal constituinte do líquido da casca da castanha de caju (LCC) in natura.In connection with our ongoing investigation in the search for new bioactive compounds using non-isoprenoid phenolic lipids from Anacardium occidentale as starting material, we describe the synthesis and cytotoxicity screening of some novel salicylate macrolactones prepared from anacardic acids, the major constitutents of natural cashew nut-shell liquid (CNSL)

    Expression of histone methyltransferases as novel biomarkers for renal cell tumor diagnosis and prognostication

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    Renal cell tumors (RCTs) are the most lethal of the common urological cancers. The widespread use of imaging entailed an increased detection of small renal masses, emphasizing the need for accurate distinction between benign and malignant RCTs, which is critical for adequate therapeutic management. Histone methylation has been implicated in renal tumorigenesis, but its potential clinical value as RCT biomarker remains mostly unexplored. Hence, the main goal of this study was to identify differentially expressed histone methyltransferases (HMTs) and histone demethylases (HDMs) that might prove useful for RCT diagnosis and prognostication, emphasizing the discrimination between oncocytoma (a benign tumor) and renal cell carcinoma (RCC), especially the chromophobe subtype (chRCC). We found that the expression levels of three genes-SMYD2, SETD3, and NO66-was significantly altered in a set of RCTs, which was further validated in a large independent cohort. Higher expression levels were found in RCTs compared to normal renal tissues (RNTs) and in chRCCs comparatively to oncocytomas. SMYD2 and SETD3 mRNA levels correlated with protein expression assessed by immunohistochemistry. SMYD2 transcript levels discriminated RCTs from RNT, with 82.1% sensitivity and 100% specificity (AUC=0.959), and distinguished chRCCs from oncocytomas, with 71.0% sensitivity and 73.3% specificity (AUC: 0.784). Low expression levels of SMYD2, SETD3, and NO66 were significantly associated with shorter disease-specific and disease-free survival, especially in patients with non-organ confined tumors. We conclude that expression of selected HMTs and HDMs might constitute novel biomarkers to assist in RCT diagnosis and assessment of tumor aggressiveness.This study was funded by research grants from Research Center of Portuguese Oncology Institute – Porto (CI-IPOP 4-2012) and European Community’s Seventh Framework Program – Grant number FP7-HEALTH-F5-2009-241783. ASP-L and FQV are and were supported by FCT-Fundação para a Ciência e a Tecnologia grants (SFRH/SINTD/94217/2013 and SFRH/ BD/70564/2010, respectively)

    Números equilibrados aritméticos e geométricos uma abordagem na metodologia de resoluções de problemas

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    This work aims to present some properties of the class of Arithmetic Balanced numbers and from these results extend to Geometric Balanced numbers, for that, we use notions and concepts of Combinatorial Analysis emphasizing the following contents Arrangement, Permutation, Factorial, Permutation with Repetition, Arithmetic and Geometric Means and the Inequality of Means, we intend to present general results related to the properties, as well as to enumerate or count for some particular cases using the notion of the Multipli- cative Principle and the Counting Principles Enabling a more fluid mechanism to obtain the counting of Arithmetic and Geometric Numbers, and from this conception, present problems related to fundamental issues in the development of the research, elaborating during the processes linked to classes of Balanced Numbers, as well as problems of the respective question banks OBMEP/OBM will be presented that address issues related to the content presented in preliminary content in order to contribute to the understanding and development of work-related themes, the proposal is in the field of Problem Solving Methodology, and it is used as a means of systematizing concepts related to Balanced numbers , exalting the importance of problematization.Este trabalho tem o objetivo de apresentar algumas propriedades da classe de números Equilibrados Aritméticos e a partir destes resultados estender para os números Equili- brados Geométricos, para isso, utilizamos noções e conceitos de Análise Combinatória dando ênfase nos seguintes conteúdos Arranjo, Permutação, Fatorial, Permutação com Repetição, Média Aritmética e Geométrica e a Desigualdade das Médias, temos por intuito apresentar resultados gerais relativos às propriedades, bem como enumerar ou contar para alguns casos particulares utilizando noção do Principio Multiplicativo e os Princípios da Contagem Possibilitando um mecanismo mais fluido para obter a contagem de Números Aritmético e Geométricos, e a partir desta concepção apresentar problemas relacionados a assuntos fundamentais no desenvolvimento da pesquisa, elaborando no decorrer dos processos vinculados a classes de números Equilibrados, como também será apresentado problemas dos respectivos bancos de questões OBMEP/OBM que abordem assuntos relacionados ao conteúdo apresentado conteúdos preliminares com a finalidade de contribuir no entendimento e desenvolvimento da temática relacionada ao trabalho, a proposta encontra-se no campo da Metodologia de Resolução de Problemas, sendo ela utilizada como meio de sistematização de conceitos referentes aos números Equilibrados, exaltando a importância da problematização
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