1,720,987 research outputs found

    Asymptotic behavior of positive solutions of a Dirichlet problem involving supercritical nonlinearities

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    summary:Let p>1p>1, q>pq>p, λ>0\lambda >0 and s]1,p[s\in ]1,p[. We study, for sps\rightarrow p^-, the behavior of positive solutions of the problem Δpu=λus1+uq1-\Delta_p u = \lambda u^{s-1}+u^{q-1} in Ω\Omega, uΩ=0u_{\mid\partial \Omega}=0. In particular, we give a positive answer to an open question formulated in a recent paper of the first author

    On a problem of Huang concerning best constants in Sobolev embeddings

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    Answering a question raised by Y.X. Huang, we prove what follows: if O is a bounded smooth domain and p > 1, then the mapping q → λq |O|^(p/q) is decreasing in ]0, p*[ and Lipschitz continuous on compact subsets of ]0, p*[, λq being the p-th power of the best Sobolev constant for the embedding of W^(1,p)(O) into L^q(O

    Existence and multiplicity of solutions for Dirichlet problems involving nonlinearities with arbitrary growth.

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    In this article we study the existence and multiplicity of solutions for the Dirichlet problem \displaylines{ -\Delta_p u=\lambda f(x,u)+ \mu g(x,u)\quad\hbox{in }\Omega,\cr u=0\quad\hbox{on } \partial \Omega} where Ω\Omega is a bounded domain in RN\mathbb{R}^N, f,g:Ω×RRf,g:\Omega \times \mathbb{R}\to \mathbb{R} are Caratheodory functions, and λ,μ\lambda,\mu are nonnegative parameters. We impose no growth condition at \infty on the nonlinearities f,g. A corollary to our main result improves an existence result recently obtained by Bonanno via a critical point theorem for C1C^1 functionals which do not satisfy the usual sequential weak lower semicontinuity property

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Power training in young athletes: Is it all in the genes?

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    Introduction. The aim of the study was to evaluate the effects of plyometric and isometric training protocol on power in 46 team sports (basketball: n = 23; volleyball: n = 23) players, also in relation to genetic background (i.e., ACE and PPARA genes polymorphisms). Methods. The following tests were administered: squat jump (SJ), countermovement jump (CMJ), drop jump (dJ), sprint, handgrip, and agility test. Genetic analysis was based on saliva samples. Results. The training protocol proved to be effective in improving jump performance in basketball players and volleyball players, respectively: 25-meter sprint test (p = 0.006; p = 0.008); agility test (p = 0.000; p = 0.000); SJ test (p = 0.001; p = 0.000); CMJ test (p = 0.005; p = 0.000); and dJ test (p = 0.03 only for basketball players; dJ test improvement in volleyball players was not significant), regardless of sports practice. Furthermore, data confirm that the 'd' allele of ACE and the 'C' allele of PPARA are positive alleles associated to power and strength performances. Conclusions. The importance to train strength skills should be emphasized, above all through isometric and plyometric exercises, not neglecting the key role played by the genetic background

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

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