Detection of Multiparticle Entanglement: Quantifying the Search for Symmetric Extensions

We provide quantitative bounds on the characterisation of multiparticle separable states by states that have locally symmetric extensions. The bounds are derived from two-particle bounds and relate to recent studies on quantum versions of de Finetti's theorem. We discuss algorithmic applications of our results, in particular a quasipolynomial-time algorithm to decide whether a multiparticle quantum state is separable or entangled (for constant number of particles and constant error in the LOCC or Frobenius norm). Our results provide a theoretical justification for the use of the Search for Symmetric Extensions as a practical test for multiparticle entanglement.Comment: 5 pages, 1 figur

Conquistas e desafios do agronegócio brasileiro.

Ponto de Vista

Transposição congenitamente corrigida das grandes artérias e coarctação da aorta: uma associação pouco comum

Congenitally corrected transposition of the great arteries, L-TGA, is a rare abnormality accounting for less than 0.5% of clinically apparent congenital heart disease. Age at time of diagnosis and survival rate are variable and depend mostly on associated anomalies. The authors present a clinical case of a twenty-four-year-old woman in whom, in a routine echocardiogram, congenitally corrected transposition of the great arteries and aortic coarctation were diagnosed, an unusual association. They describe the results of complementary exams (echocardiography, chest X-ray, electrocardiogram and cardiac angiography) that they believe to be useful for the correct diagnosis of this clinical situation. Additionally, the authors make a brief review of the literature relevant to the case

Context-aware mass customization construction system: methods for user captured as-built plans

The problem of context, a fundamental aspect of dealing with built environments, has not been adequately addressed by mass customization systems so far, which has limited their scope of application. The aim of the present article is to evaluate the adequacy of existing methods of producing as-built plans of rooms by non-expert users for the automatic generation and production of partition walls for building renovation. This paper highlights criteria to develop appropriate methods of capturing context for mass customization construction systems.info:eu-repo/semantics/publishedVersio

Nuno Portas and the Spanish influence on the definition of housing policies in Portugal in the period of democratic transition

Taking the housing crisis and the SAAL program as a central interest point of architects and sociologists in the aftermath of the Portuguese revolution, this chapter tracks the influence of Spanish architecture in Portugal and the relations of Portuguese and Spanish architects, signaling the main role of Nuno Portas. It begins by introducing the background of the architecture exchange between Portugal and Spain, since the 1960’s, through the diffusion and interchange activities of Nuno Portas (section 2). It continues to discuss the role of architects on urban change during the revolutionary process from the viewpoint Joan Antonio Solans experiences and writings (Section 3). Then it takes on the social movements debate with Manuel Castells reflections and writings about the new housing policies and experiences (Section 4). Finally, a short reflection on the interchange of ideas and experiences between Portugal and Spain in presented in the conclusion (Section 5).info:eu-repo/semantics/submittedVersio

Are all maximally entangled states pure?

We study if all maximally entangled states are pure through several entanglement monotones. In the bipartite case, we find that the same conditions which lead to the uniqueness of the entropy of entanglement as a measure of entanglement, exclude the existence of maximally mixed entangled states. In the multipartite scenario, our conclusions allow us to generalize the idea of monogamy of entanglement: we establish the \textit{polygamy of entanglement}, expressing that if a general state is maximally entangled with respect to some kind of multipartite entanglement, then it is necessarily factorized of any other system.Comment: 5 pages, 1 figure. Proof of theorem 3 corrected e new results concerning the asymptotic regime include

The quantum one-time pad in the presence of an eavesdropper

A classical one-time pad allows two parties to send private messages over a public classical channel -- an eavesdropper who intercepts the communication learns nothing about the message. A quantum one-time pad is a shared quantum state which allows two parties to send private messages or private quantum states over a public quantum channel. If the eavesdropper intercepts the quantum communication she learns nothing about the message. In the classical case, a one-time pad can be created using shared and partially private correlations. Here we consider the quantum case in the presence of an eavesdropper, and find the single letter formula for the rate at which the two parties can send messages using a quantum one-time pad

Análise de preços agrícolas.

Recentemente, muitos analistas vêm se dedicando a examinar o crescimento dos preços de commodities. A Tabela 1 mostra que tem havido aumentos de preços expressivos para commodities agrícolas. Entre 2004 e 2007, o preço do trigo aumentou 48 %, o do milho 33 % e o do arroz 23 %. A soja ? que já estava com preços elevados em 2004 ? subiu mais 4 %. Os óleos vegetais, a soja e a palma, também mostraram aumentos importantes: 23 % e 50 %, respectivamente, entre 2004 e 2007. O açúcar atingiu o preço mais elevado em 2006, mas continua com seu preço 20 % acima do valor alcançado em 2004.Na publicação: Eliseu Alves

Commodities agrícolas e preço do petróleo.

Este artigo tem por objetivo documentar estatisticamente a relação entre preços internacionais de produtos agrícolas e o preço internacional do petróleo. Inicialmente caracteriza-se a relação entre o preço do petróleo e o preço da ureia e, em seguida, como o preço desta e das commodities escolhidas para o estudo se comportam. Os resultados mostram que a tendência no preço desses produtos é influenciada de maneira significativa pela tendência no preço do petróleo. As elasticidades estimadas estão entre 0,47 e 0,61, indicando que entre 50% e 60% das variações no preço do petróleo são transmitidas para os produtos. Ademais, choques transitórios no preço do petróleo têm impactos fortes e duradouros sobre os preços desses produtos.Na publicação: Eliseu Alves