Closed string thermal torus from thermo field dynamics

In this Letter a topological interpretation for the string thermal vacuum in the thermo field dynamics (TFD) approach is given. As a consequence, the relationship between the imaginary time and TFD formalisms is achieved when both are used to study closed strings at finite temperature. The TFD approach starts by duplicating the system's degrees of freedom, defining an auxiliary (tilde) string. In order to lead the system to finite temperature a Bogoliubov transformation is implemented. We show that the effect of this transformation is to glue together the string and the tilde string to obtain a torus. The thermal vacuum appears as the boundary state for this identification. Also, from the thermal state condition, a Kubo-Martin-Schwinger condition for the torus topology is derived. © 2005 Elsevier B.V. All rights reserved.

A ficção científica e o ensino de ciências: o imaginário como formador do real e do racional

Este artigo apresenta uma reflexão sobre a inserção da ficção científica no ensino de Ciências, no qual buscamos identificar como a ficção científica incorpora elementos na estrutura conceitual dos educandos partindo do pressuposto de que teria um papel de desencadeadora e/ou organizadora da aprendizagem. O filme Jurassic Park foi estudado como constitutivo do conhecimento, transmutando o ficcional no real/racional, possibilitando a organização hierárquica dos conceitos, acrescendo novos elementos na estrutura conceitual dos educandos e atuando, também, na mediação do conhecimento - ora organizando, ora desencadeando.

A sensor for monitoring the volume of nutrient in a solid substrate-based growth media by using electrochemical admittance spectroscopy

A sensor was fashioned to monitor the volume of nutrient in a solid substrate-based growth media by using electrochemical admittance spectroscopy. Several experimental parameters were investigated (i.e. The use of two- or three-electrode cells, the superficial area of the electrode, the amount of nutrient solution added to the growth media, and the influence of varying the dc and ac potential) to assess how these variables affect the admittance of the system. A linear correlation was observed between the maximum of the imaginary admittance and the volume of nutrient present. The response factor was 2.8 x 10(-5) S cm(-2) ml(-1) and the limit of detection (LOD) was 0.54 ml. The humidity of the growth media does not change the response of the nutrient toward the monitoring measurements. These results demonstrate that the volume of nutrient in this solid substrate-based growth media can be assessed using a ceramic sensor to measure the imaginary admittance. (C) 2002 Elsevier B.V. B.V. All rights reserved.

O doente imaginário, de Molière, encenado pelo Teatro do Ornitorrinco (1989)

Pós-graduação em Artes - IA

Referências históricas e o realismo mágico em Il barone rampante, de Italo Calvino

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Mito e realidade em Hesíodo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A expressão da cultura nobiliárquica nos livros de viagens medievais

Pós-graduação em História - FCHS

Crime, ordem e violência em São Paulo: a percepção do nível de violência urbana no município de Assis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Imaginários e representações da morte: caminhando sobre o fio da navalha

Pós-graduação em Serviço Social - FCHS

Técnicas avançadas para caracterização de processos de transporte dependente do Spin

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Esporte escolar e emancipação humana: reflexões à luz da ontologia marxiana

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Tempo de festas: homenagens a Santa Bárbara, N. S. da Conceição e Sant'Ana em Salvador (1860-1940)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Entre o Pavilhão Mexicano e o Cine Azteca: cultura visual e formação de identidade no Brasil e México na primeira metade do século XX

The article seeks to reflect from a visual history of the elaboratión imaginary political and national identities and transnational comparative perspective between Brazil and Mexico in the first half of the twentieth century. The main focus is Mexican participation in the exhibition commemorating the centennial of Brazilian independence in 1922 and the dialogues in the film industry of both countries in the second half of the 1940s and beginning of 1950s.

THE IMAGINARY ABOUT THE SCHOOL and THE POSSIBILITIES of AN EQUALITARIAN SCHOOL: A STUDY on THE BRAZILIAN STATE SCHOOLS

The main objective of the article is to reflect on the imaginary that the teachers of two public schools have of their students and the school they work in and the ideal of an inclusive and democratic school. In this article, we reflect on the image that the teachers of two public schools in the city of Rio Claro, São Paulo State, Brazil, have of their students and their school as an institution. We use the studies of imaginary sociology as a theoretic reference base. Castoriadis (1986); Taylor (2006); Legros et al (2007) and Baczo (1984) are the referenced authors of this article. (C) 2012 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of The Association of Science, Education and Technology