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Narcisismo na comunidade científica: entrevista com Bruno Lemaitre
No full textBruno Lemaitre (born September 21, 1965, in Lille, France) is an immunologist and professor at the Ecole Polytechnique Fédérale de Lausanne (Switzerland). His research focuses on the mechanisms of innate immunity and endosymbiosis in Drosophila. One of his early discoveries demonstrated that the Toll receptor protein and its downstream signaling pathway are essential components of the fruit fly immune response (Lemaitre et al., 1996). The 2011 Nobel Prize in Physiology or Medicine recognized the findings of Lemaitre et al. (1996). This pioneering work on innate immunity facilitated the identification of Toll-like receptors as crucial mediators of human innate immunity. Bruno has received several research awards, including the Noury, Thorlet and Lazare Prize of the French Academy of Sciences (2001), the First Prize of the Schlumberger Foundation (2002), the William B. Coley Prize (2003), the Lucien Tartois Prize of the Foundation for Medical Research (2006), and the Liliane Bettencourt Prize for Life Sciences (2010). Lemaitre is also the author of several books on the subject of this interview and a book on the philosophy of Michael Polanyi (Lemaitre, 2022).Bruno Lemaitre (nascido a 21 de setembro de 1965 em Lille, França) é imunologista e professor da Escola Politécnica Federal de Lausanne (Suíça). A sua investigação centra-se nos mecanismos de imunidade inata e endossimbiose da Drosophila. Uma das suas descobertas iniciais demonstrou que a proteína recetora Toll e a sua via de sinalização a jusante são componentes essenciais da resposta imune da mosca da fruta (Lemaitre et al., 1996). O Prémio Nobel de Fisiologia ou Medicina de 2011 reconheceu os resultados obtidos em Lemaitre et al. 1996). Esse trabalho pioneiro em imunidade inata facilitou a identificação de recetores Toll como mediadores cruciais da imunidade inata humana. Bruno recebeu vários prémios de investigação como o Prémio Noury, Thorlet e Lazare da Academia Francesa de Ciências (2001), o Primeiro Prémio da Fundação Schlumberger (2002), o Prémio William B. Coley (2003), o Prémio Lucien Tartois da Fundação para a Investigação Médica (2006) e o Prémio Liliane Bettencourt de Ciências da Vida (2010). Lemaitre também é autor de vários livros sobre o tema desta entrevista e de um livro sobre a filosofia de Michael Polanyi (Lemaitre, 2022)
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
On perturbed Szego recurrences
Get PDFThe purpose of the present contribution is to investigate the effects of finite modifications of Verblunsky coefficients on Szego recurrences. More precisely, we study the structural relations and the corresponding C-functions of the orthogonal polynomials with respect to these modifications from the initial ones. (C) 2013 Elsevier Inc. All rights reserved.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Ministerio da CienciaTecnologia e Inovacao of BrazilDireccion General de Investigacion, Ministerio de Economia y Competitividad of SpainUniv Estadual Paulista UNESP, Dept Matemat Aplicada, BR-15054000 Sao Jose Do Rio Preto, SP, BrazilUniv Estadual Paulista UNESP, Dept Matemat Aplicada, BR-15054000 Sao Jose Do Rio Preto, SP, BrazilTecnologia e Inovacao of Brazil370291/2013-1Direccion General de Investigacion, Ministerio de Economia y Competitividad of SpainMTM2012-36732-C03-0
On some Problems in the Theory of Orthogonal Polynomials
No full textTese no âmbito do Programa Interuniversitário de Doutoramento em Matemática, apresentada ao Departamento de
Matemática da Faculdade de Ciências e Tecnologia da Universidade de Coimbra.In this thesis we solve several problems in the theory of orthogonal polynomial sequences (OPS). In bellow we summarize the main contributions.
(i) Let be a nonzero linear functional acting on the space of polynomials . Let be a Hahn operator acting on the dual space of polynomials . Suppose that there exist polynomials and , with and , so that the functional equation
\begin{align}\nonumber
\mathbf{D}_{q,\omega}(\phi {\bf u})=\psi{\bf u}
\end{align}
holds, where the involved operations are defined in the distributional sense. We state necessary and sufficient conditions, involving only the coefficients of and , such that is regular, that is, there exists an OPS with respect to . In addition, the coefficients of the three-term recurrence relation (TTRR) satisfied by the corresponding monic OPS are given, as well as a distributional Rodrigues-type formula, which holds without assuming that is regular.
(ii) Let and be fixed non-negative integer numbers and let be a polynomial of degree . Suppose that and are two OPS such that
%\begin{align}\nonumber %\label{coherence-outline}
\pi_N(x)\,P_{n+m}^{(m)}(x)= \sum_{j=n-M}^{n+N}r_{n,j}Q_{j+k}^{(k)}(x)\quad (n=0,1,\ldots)\,, \eqno(*)
%\end{align}
where are complex numbers independent of . It is shown that under some natural constraints, and are semiclassical OPS. That is, there exist nonzero polynomials , , and such that the corresponding functionals and fulfill the functional equations Moreover we show that and are related by a rational modification in the distributional sense, meaning that for some nonzero polynomials . This leads us to introduce the concept of coherent pairs with index and order .
(iii) We extend the previous concept to the one of --coherent pairs with index and order , which appears in the framework of discrete OPS by replacing in the ordinary derivative by the discrete Hahn's operator . This leads to the (structure) relation
\begin{align}\nonumber %\label{coherence-outline-discrete}
\pi_N(x)\,D_{q,\omega} ^m P_{n+m} (x)= \sum_{j=n-M}^{n+N}r_{n,j}D_{q,\omega} ^k Q_{j+k}(x)\quad (n=0,1,\ldots)\,.
\end{align}
Again, in this situation, it is shown that under some natural constraints, and are semiclassical OPS (with respect to ) and the corresponding functionals are related by a (distributional) rational modification. Some examples of application are given, recovering in a more simple way some known results in the literature about the subject. Our results enable us to describe in a unified way all the classical OPS with respect to Jackson's operator, which appear as special or limiting cases of a four parametric family of -polynomials.
(iv) Let us consider now that is a functional on satisfying the more general functional equation
\begin{align}\nonumber %\label{Dx-u-outline}
\mathbf{D}_x(\phi {\bf u})={\bf S}_x(\psi{\bf u}),
\end{align}
where and are operators defined on in the usual way, in the framework of the theory of OPS on a nonuniform lattice, , that includes as a special case the lattice associated with the so-called Askey-Wilson operator, namely . We state necessary and sufficient conditions for the regularity of , giving, in addition, closed formulas for the coefficients of the TTRR of the corresponding monic OPS, as well as a Rodrigues-type formula. Some examples are given to point out the power of our formulas in the framework of classical OPS on nonuniform lattices. In particular, our results enable us to derive in a simple way the coefficients of the TTRR of the Racah polynomials as well as the ones for the Askey-Wilson polynomials.
(v) Let be a monic OPS and a polynomial of a degree at most two such that
for some complex sequences coefficients , and . M. E. H. Ismail posed the problem of characterizing all OPS fulfilling this structure relation, for the lattice associated with the Askey-Wilson operator. Ismail conjectured (see \cite[Conjecture 24.7.8]{I2005}) that the continuous Jacobi polynomials, the Al-Salam-Chihara polynomials, or special or limiting cases of them, are the only OPS fulfilling the structure relation. Using the main result obtained in (iv) we give a positive answer to Ismail's conjecture.Nesta dissertação resolvem-se vários problemas na âmbito da teoria das sucessões de polinómios ortogonais (SPO). As contribuições principais apresentadas são descritas em seguida.
(i) Seja uma funcional linear não nula definida sobre o espaço dos polinómios, . Seja um operador de Hahn que actua no espaço dual . Suponha-se que existem polinómios e , com e polinómios de graus não superiores a e , respectivamente, tais que satisfaz a equação funcional
\begin{align}\nonumber
\mathbf{D}_{q,\omega}(\phi {\bf u})=\psi{\bf u}\;,
\end{align}
onde as operações são definidas no sentido usual da teoria das distribuições.
Estabelecem-se condições necessárias e suficientes, envolvendo apenas os coeficientes de e , tais que é regular, isto é, existe uma SPO a respeito de . Além disso, os coeficientes da relação de recorrência a três termos (RRTT) verificada pela correspondente SPO mónica são dados de forma explícita. É também apresentada uma fórmula de tipo Rodrigues distribucional, a qual se verifica mesmo que não seja regular.
(ii) Sejam e números inteiros não negativos fixados e um polinómio de grau . Sejam e duas SPO tais que
%\begin{align}\nonumber %\label{coherence-outline}
\pi_N(x)\,P_{n+m}^{(m)}(x)= \sum_{j=n-M}^{n+N}r_{n,j}Q_{j+k}^{(k)}(x)\quad (n=0,1,\ldots)\,, \eqno(*)
onde cada é um número complexo independente de . Prova-se que, sob certas reservas naturais, e são SPO semiclássicas, isto é, existem polinómios não nulos , , e tais que as correspondentes funcionais regulares e satisfazem as equações funcionais Prova-se ainda que e estão relacionados por uma modificação racional, no sentido distribucional, o que significa que para certos polinómios . Estes factos conduzem ao conceito de pares coerentes de índice e ordem .
(iii) O conceito anterior é estendido para o conceito de pares --coerentes de índice e ordem , no contexto das SPO discretas, substituindo em o operador derivada usual pelo operador de Hahn . Isto conduz à relação de estrutura
\begin{align}\nonumber %\label{coherence-outline-discrete}
\pi_N(x)\,D_{q,\omega} ^m P_{n+m} (x)= \sum_{j=n-M}^{n+N}r_{n,j}D_{q,\omega} ^k Q_{j+k}(x)\quad (n=0,1,\ldots)\,.
\end{align}
De novo, nesta situação, mostra-se que, assumindo certas condições naturais, e são SPO semiclássicas (a respeito de ) e que as funcionais regulares associadas estão relacionadas por uma modificação racional (no sentido distribucional). São apresentados alguns exemplos de aplicação, recuperando de forma simples alguns resultados conhecidos na literatura. Os resultados apresentados permitem ainda descrever de forma unificada todas as SPO clássicas a respeito do operador de Jackson, as quais são representadas como casos especiais ou caso limite de uma família de -polinómios envolvendo quatro parâmetros.
(iv) Seja agora uma funcional linear em que satisfaz a equação funcional mais geral
\begin{align}\nonumber %\label{Dx-u-outline}
\mathbf{D}_x(\phi {\bf u})={\bf S}_x(\psi{\bf u}),
\end{align}
onde e são operadores definidos em da maneira usual, no contexto da teoria das SPO em redes não uniformes, , o que inclui como caso especial a rede associada ao chamado operador de Askey-Wilson, nomeadamente, . Estabelecem-se condições necessárias e suficientes para a regularidade de . Para além disso, dão-se fórmulas fechadas para os coeficientes da RRTT da correspondente SPO mónica, bem como uma fórmula de tipo Rodrigues. São apresentados alguns exemplos que evidenciam que tais fórmulas são muito poderosas no contexto das SPO clássicas em redes não uniformes. Em particular, os resultados obtidos permitem obter de forma simples os coeficientes da RRTT para os polinómios de Racah, bem como para os polinómios de Askey-Wilson.
(v) Sejam uma SPO mónica e um polinómio de grau quando muito igual a dois que satisfazem a relação de estrutura
onde , e são parâmetros reais ou complexos. M. E. H. Ismail colocou o problema de caracterizar tais SPO para a rede associada ao operador de Askey-Wilson. Ismail conjecturou (veja-se \cite[Conjecture 24.7.8]{I2005}) que os polinómios Jacobi contínuos, os polinómios de Al-Salam Chihara, ou casos especiais ou limite destes, constituem as únicas SPO que satisfazem aquela relação de estrutura. Usando o resultado principal estabelecido em (iv), damos uma resposta positiva à conjectura de Ismail
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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