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Padrões e características da remuneração de executivos de empresas brasileiras de capital aberto

Ferreira, Lucas Oliveira Gomes
Fonte: Universidade de Brasília Publicador: Universidade de Brasília
Tipo: Dissertação
POR
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Dissertação (mestrado)—Universidade de Brasília, Universidade Federal da Paraíba, Universidade Federal do Rio Grande do Norte, Programa Multi-Institucional e Inter-Regional de Pós-Graduação em Ciências Contábeis, 2012.; O objetivo do presente estudo é conhecer os padrões e características da remuneração de executivos de empresas de capital aberto negociadas na Bolsa de Valores de São Paulo (Bovespa) no período 2010-2011. Os dados da amostra se referem somente aos anos de 2010 e 2011, pois a Comissão de Valores Mobiliários (CVM) só passou a exigir divulgação dessas informações a partir de 2010. A amostra final de 119 empresas foi selecionada conforme grau de liquidez com base em quantidade de negociação, totalizando 238 observações nos 2 anos. Os resultados indicam considerável resistência à publicação desse tipo de informação pelas empresas, pois do total de 119 empresas, 39 obtiveram liminar na justiça para não divulgar o item 13.11 do Formulário de Referência (FR), referente ao número de membros e valores de remuneração por Conselho. A remuneração dos executivos no Brasil é principalmente formada por remuneração fixa e a remuneração total média por membro da Diretoria Estatutária é de R$ 2...

ON THE VITALI-HAHN-SAKS AND NIKODÝM THEOREMS

Brooks, James K.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1969 EN
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We present simplified proofs of the well-known Vitali-Hahn-Saks and Nikodým theorems for measures.

Molecular Insight into the Steric Shielding Effect of PEG on the Conjugated Staphylokinase: Biochemical Characterization and Molecular Dynamics Simulation

Mu, Qimeng; Hu, Tao; Yu, Jingkai
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 18/07/2013 EN
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PEGylation is a successful approach to improve potency of a therapeutic protein. The improved therapeutic potency is mainly due to the steric shielding effect of PEG. However, the underlying mechanism of this effect on the protein is not well understood, especially on the protein interaction with its high molecular weight substrate or receptor. Here, experimental study and molecular dynamics simulation were used to provide molecular insight into the interaction between the PEGylated protein and its receptor. Staphylokinase (Sak), a therapeutic protein for coronary thrombolysis, was used as a model protein. Four PEGylated Saks were prepared by site-specific conjugation of 5 kDa/20 kDa PEG to N-terminus and C-terminus of Sak, respectively. Experimental study suggests that the native conformation of Sak is essentially not altered by PEGylation. In contrast, the bioactivity, the hydrodynamic volume and the molecular symmetric shape of the PEGylated Sak are altered and dependent on the PEG chain length and the PEGylation site. Molecular modeling of the PEGylated Saks suggests that the PEG chain remains highly flexible and can form a distinctive hydrated layer, thereby resulting in the steric shielding effect of PEG. Docking analyses indicate that the binding affinity of Sak to its receptor is dependent on the PEG chain length and the PEGylation site. Computational simulation results explain experimental data well. Our present study clarifies molecular details of PEG chain on protein surface and may be essential to the rational design...

Global sampling of plant roots expands the described molecular diversity of arbuscular mycorrhizal fungi

Opik, M.; Zobel, M.; Cantero, J.; Davison, J.; Facelli, J.; Hiiesalu, I.; Jairus, T.; Kalwij, J.; Koorem, K.; Leal, M.; Liira, J.; Metsis, M.; Neshtaeva, V.; Paal, J.; Phosri, C.; Polme, S.; Reier, U.; Saks, U.; Schimann, H.; Thiery, O.; et al.
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
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We aimed to enhance understanding of the molecular diversity of arbuscular mycorrhizal fungi (AMF) by building a new global dataset targeting previously unstudied geographical areas. In total, we sampled 96 plant species from 25 sites that encompassed all continents except Antarctica. AMF in plant roots were detected by sequencing the nuclear SSU rRNA gene fragment using either cloning followed by Sanger sequencing or 454-sequencing. A total of 204 AMF phylogroups (virtual taxa, VT) were recorded, increasing the described number of Glomeromycota VT from 308 to 341 globally. Novel VT were detected from 21 sites; three novel but nevertheless widespread VT (Glomus spp. MO-G52, MO-G53, MO-G57) were recorded from six continents. The largest increases in regional VT number were recorded in previously little-studied Oceania and in the boreal and polar climatic zones — this study providing the first molecular data from the latter. Ordination revealed differences in AM fungal communities between different continents and climatic zones, suggesting that both biogeographic history and environmental conditions underlie the global variation of those communities. Our results show that a considerable proportion of Glomeromycota diversity has been recorded in many regions...

Banach-Saks operators on spaces of continuous functions

Núñez, Carmelo
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em //1992 ENG
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Let K be a compact Hausdorff space and let E be a Banach space. We denote by C(K, E) the Banach space of all E-valued continuous functions defined on K, endowed with the supremum norm. We study in this paper Banach-Saks operators defined on C(K, E) spaces. We characterize these operators for a large class of compacts K (the scattered ones), or for a large class of Banach spaces E (the superreflexive ones). We also show by some examples that our theorems can not be extended directly.; The original publication is available at www.springerlink.com

Partições de inteiros e dualidade em estruturas combinatórias

Martins, Inês Neves Louro Legatheaux
Fonte: Universidade de Lisboa Publicador: Universidade de Lisboa
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em //2007 POR
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Tese de mestrado em Matemática (Álgebra, Lógica e Fundamentos), apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2008; Nos anos oitenta, M. Albertson apresenta um contexto geral para formular problemas de dualidade, considerando hipergrafos e associando-lhes as sucessões das diferenças entre dois termos consecutivos da sucessão das dimensões e da sucessão de estabilidade. Os teoremas de dualidade traduzem-se pela igualdade do primeiro termo de uma das sucessões com o comprimento da outra. Surge naturalmente a questão de saber para que estruturas combinatórias as sucessões das diferenças formam partições e que relação existe entre as duas. Em 1986, M. Saks observa que os teoremas de dualidade provêm de pares antibloco de hipergrafos, colocando a questão anterior neste contexto. Esta dissertação pretende mostrar que a linguagem dos hipergrafos permite unificar resultados clássicos e recentes sobre diversas estruturas combinatórias. Nesse sentido, são apresentados teoremas de C. Greene e D. Kleitman que generalizam os teoremas duais de Dilworth e Mirsky sobre conjuntos parcialmente ordenados. Verifica-se que esta generalização é consequência das sucessões das diferenças associadas ao par antibloco dos hipergrafos das anticadeias e cadeias serem partições conjugadas. O estudo do par antibloco dos hipergrafos dos emparelhamentos e estrelas de um multigrafo bipartido permite reencontrar um resultado de D. de Werraque estabelece que a sucessão das diferenças dos emparelhamentos forma uma partição da cardinalidade do conjunto de arestas. Segundo M. Saks...

The weak Banach-Saks Property of the Space $(L_\mu^p)^m$

Jiang, Zhenglu; Fu, Xiaoyong
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 19/02/2007
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In this paper we show the weak Banach-Saks property of the Banach vector space $(L_\mu^p)^m$ generated by $m$ $L_\mu^p$-spaces for $1\leq p<+\infty,$ where $m$ is any given natural number. When $m=1,$ this is the famous Banach-Saks-Szlenk theorem. By use of this property, we also present inequalities for integrals of functions that are the composition of nonnegative continuous convex functions on a convex set of a vector space ${\bf R}^m$ and vector-valued functions in a weakly compact subset of the space $(L_\mu^p)^m$ for $1\leq p<+\infty$ and inequalities when these vector-valued functions are in a weakly* compact subset of the product space $(L_\mu^\infty)^m$ generated by $m$ $L_\mu^\infty$-spaces.; Comment: 7

The Banach-Saks Property of the Banach Product Spaces

Jiang, Zhenglu; Fu, Xiaoyong
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 19/02/2007
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In this paper we first take a detail survey of the study of the Banach-Saks property of Banach spaces and then show the Banach-Saks property of the product spaces generated by a finite number of Banach spaces having the Banach-Saks property. A more general inequality for integrals of a class of composite functions is also given by using this property.; Comment: 6

The weak Banach-Saks property for function spaces

Curbera, Guillermo P.; Ricker, Werner J.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 17/12/2015
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We establish the weak Banach-Saks property for function spaces arising as the optimal domain of an operator.

Weak Banach-Saks property and Komlos theorem for preduals of JBW$^*$-triples

Peralta, Antonio M.; Pfitzner, Hermann
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 20/05/2015
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We show that the predual of a JBW$^*$-triple has the weak Banach-Saks property, that is, reflexive subspaces of a JBW$^*$-triple predual are super-reflexive. We also prove that JBW$^*$-triple preduals satisfy the Koml\'os property (which can be considered an abstract version of the weak law of large numbers). The results rely on two previous papers from which we infer the fact that, like in the classical case of $L^1$, a subspace of a JBW$^*$-triple predual contains $\ell_1$ as soon as it contains uniform copies of $\ell_1^n$.

Noncommutative Vitali-Hahn-Saks Theorem holds precisely for finite $W^\ast$-algebras

Chetcuti, E.; Hamhalter, J.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 01/11/2007
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It is shown that the bona fide generalization of the Vitali-Hahn-Saks Theorem to von Neumann algebras is possible if, and only if, the algebra is finite. This settles the problem on the noncommutative Vitali-Hahn-Saks Theorem completely and provides new means of characterizing finite von Neumann algebras.; Comment: 8 pages

Properties of Hadamard directional derivatives: Denjoy-Young-Saks theorem for functions on Banach spaces

Zajicek, Ludek
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/08/2013
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The classical Denjoy-Young-Saks theorem on Dini derivatives of arbitrary functions $f: \R \to \R$ was extended by U.S. Haslam-Jones (1932) and A.J. Ward (1935) to arbitrary functions on $\R^2$. This extension gives the strongest relation among upper and lower Hadamard directional derivatives $f^+_H (x,v)$, $f^-_H (x,v)$ ($v \in X$) which holds almost everywhere for an arbitrary function $f:\R^2\to \R$. Our main result extends the theorem of Haslam-Jones and Ward to functions on separable Banach spaces.

Module weak Banach-Saks and module Schur properties of Hilbert C*-modules

Frank, M.; Pavlov, A. A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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Continuing the research on the Banach-Saks and Schur properties started in (cf. M. Frank, A. A. Pavlov, Banach-Saks properties of C*-algebras and Hilbert C*-modules (submitted)) we investigate analogous properties in the module context. As an environment serves the class of Hilbert C*-modules. Some properties of weak module topologies on Hilbert C*-modules are described. Natural module analogues of the classical weak Banach-Saks and the classical Schur properties are defined and studied. A number of useful characterizations of properties of Hilbert C*-modules is obtained. In particular, some interrelations of these properties with the self-duality property of countably generated Hilbert C*-modules are established.; Comment: 19 pages / replaced with minor additions, corrections, reformulations

A counterexample to the Alon-Saks-Seymour conjecture and related problems

Huang, Hao; Sudakov, Benny
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/02/2010
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Consider a graph obtained by taking edge disjoint union of $k$ complete bipartite graphs. Alon, Saks and Seymour conjectured that such graph has chromatic number at most $k+1$. This well known conjecture remained open for almost twenty years. In this paper, we construct a counterexample to this conjecture and discuss several related problems in combinatorial geometry and communication complexity.

On Online Labeling with Polynomially Many Labels

Babka, Martin; Bulánek, Jan; Čunát, Vladimír; Koucký, Michal; Saks, Michael
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/10/2012
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In the online labeling problem with parameters n and m we are presented with a sequence of n keys from a totally ordered universe U and must assign each arriving key a label from the label set {1,2,...,m} so that the order of labels (strictly) respects the ordering on U. As new keys arrive it may be necessary to change the labels of some items; such changes may be done at any time at unit cost for each change. The goal is to minimize the total cost. An alternative formulation of this problem is the file maintenance problem, in which the items, instead of being labeled, are maintained in sorted order in an array of length m, and we pay unit cost for moving an item. For the case m=cn for constant c>1, there are known algorithms that use at most O(n log(n)^2) relabelings in total [Itai, Konheim, Rodeh, 1981], and it was shown recently that this is asymptotically optimal [Bul\'anek, Kouck\'y, Saks, 2012]. For the case of m={\Theta}(n^C) for C>1, algorithms are known that use O(n log n) relabelings. A matching lower bound was claimed in [Dietz, Seiferas, Zhang, 2004]. That proof involved two distinct steps: a lower bound for a problem they call prefix bucketing and a reduction from prefix bucketing to online labeling. The reduction seems to be incorrect...

Khinchin inequality and Banach-Saks type properties in rearrangement-invariant spaces

Sukochev, F.; Zanin, D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 14/01/2010
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{\it We study the class of all rearrangement-invariant (=r.i.) function spaces $E$ on $[0,1]$ such that there exists $00$ does not depend on $n$. We completely characterize all Lorentz spaces having this property and complement classical results of Rodin and Semenov for Orlicz spaces $exp(L_p)$, $p\ge 1$. We further apply our results to the study of Banach-Saks index sets in r.i. spaces.

The convex hull of a Banach-Saks set

Ruiz, C.; Lopez-Abad, J.; Tradacete, P.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 21/09/2012
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A subset $A$ of a Banach space is called Banach-Saks when every sequence in $A$ has a Ces{\`a}ro convergent subsequence. Our interest here focusses on the following problem: is the convex hull of a Banach-Saks set again Banach-Saks? By means of a combinatorial argument, we show that in general the answer is negative. However, sufficient conditions are given in order to obtain a positive result.; Comment: 29 pages

On the complexity of some classes of Banach spaces and non-universality

Braga, Bruno de Mendonça
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 08/08/2015
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These notes are dedicated to the study of the complexity of several classes of separable Banach spaces. We compute the complexity of the Banach-Saks property, the alternating Banach-Saks property, the complete continuous property, and the LUST property. We also show that the weak Banach-Saks property, the Schur property, the Dunford-Pettis property, the analytic Radon-Nikodym property, the set of Banach spaces whose set of unconditionally converging operators is complemented in its bounded oper- ators, the set of Banach spaces whose set of weakly compact operators is complemented in its bounded operators, and the set of Banach spaces whose set of Banach-Saks opera- tors is complemented in its bounded operators, are all non Borel in SB. At last, we give several applications of those results to non-universality results.

Quantification of the Banach-Saks property

Bendová, Hana; Kalenda, Ondřej F. K.; Spurný, Jiří
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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We investigate possible quantifications of the Banach-Saks property and the weak Banach-Saks property. We prove quantitative versions of relationships of the Banach-Saks property of a set with norm compactness and weak compactness. We further establish a quantitative version of the characterization of the weak Banach-Saks property of a set using uniform weak convergence and $\ell_1$-spreading models. We also study the case of the unit ball and in this case we prove a dichotomy which is an analogue of the James distortion theorem for $\ell_1$-spreading models.; Comment: 18 pages; we added some references to related results, remarks on this relationship, the proof of one lemma was simplified

The Alon-Saks-Seymour and Rank-Coloring Conjectures

Tait, Michael
Fonte: University of Delaware Publicador: University of Delaware
Tipo: Tese de Doutorado
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Cioaba, Sebastian; This thesis studies the Alon-Saks-Seymour Conjecture and the Rank-Coloring Conjecture and their relationships to computer science. For a graph G, the chromatic number, x(G), is the minimum number of colors needed to properly color the vertices of G. If A(G) is the adjacency matrix of G, then rank(A(G)) denotes its rank. The biclique partition number, bp(G), is the minimum number of complete bipartite subgraphs (bicliques) necessary to partition the edge set of G. The Rank-Coloring Conjecture states that for any graph G, x(G) <= rank(A(G)) and the Alon-Saks- Seymour Conjecture states that for any graph G, x(G) <= bp(G) + 1. Both of these conjectures have been previously disproven. In this thesis we construct an in nite family of graphs that are counterexamples to both conjectures. This construction generalizes previous work of Razborov and Huang and Sudakov. We discuss the relationship between these conjectures and questions in theoretical computer science relating to communication complexity, which is the amount of information that two parties need to exchange in order to compute some objective boolean function. We also discuss a generalization of biclique partitions to hypergraphs, where we consider the minimum number of complete r- partite r-uniform hypergraphs necessary to partition the edge set of the complete r-uniform hypergraph on n vertices.; University of Delaware...