A fluidized granular medium as an instance of the Fluctuation Theorem

We study the statistics of the power flux into a collection of inelastic beads maintained in a fluidized steady-state by external mechanical driving. The power shows large fluctuations, including frequent large negative fluctuations, about its average value. The relative probabilities of positive and negative fluctuations in the power flux are in close accord with the Fluctuation Theorem of Gallavotti and Cohen, even at time scales shorter than those required by the theorem. We also compare an effective temperature that emerges from this analysis to the kinetic granular temperature.Comment: 4 pages, 5 figures, submited to Physical Review Letters; Revised versio

Sobre o feminino e a cidadania em Pompéia

Nos últimos anos, novos trabalhos tem questionado os antigos paradigmas interpretativos que excluíam a mulher do espaço público e do grupo de cidadaos. O objetivo deste artigo é refletir sobre a idéia equivocada do confin amento feminino ao lar e de sua exclusao da vida pública e do poder, durante o século 1 d.C. A análise de inscriçoes parietais de Pompéia tem sido importante para questionar esta imagem sobre as mulheres romanas.In the last years, recent studies have been criticising interpretative paradigms that have been excluding the women from the public space and citizeruy. The aim of this article is to make us think about the wrong idea of the female confinement at home and her exclusion from public life and levels of power, during the 1 century a.C. The analysis of several inscriptions from Pompeii has been important in order to put discuss the image of Roman women

DODAB and DODAC bilayer-like aggregates in the micromolar surfactant concentration domain

In the millimolar concentration domain (typically 1 mM), dioctadecyldimethylammonium bromide and chloride (DODAX, X representing Br- or Cl- counterions) molecules assemble in water as large unilamellar vesicles. Differential scanning calorimetry (DSC) is a suitable technique to obtain the melting temperature (Tm) characteristic of surfactant bilayers, while fluorescence spectroscopy detects formation of surfactant aggregates, like bilayers. These two techniques were combined to investigate the assemble of DODAX molecules at micromolar concentrations, from 10 to 100 micromolar. At 1 mM surfactant, Tm ~ 45 ºC and 49 oC, respectively for DODAB and DODAC. DSC and fluorescence of Nile Red were used to show the formation of DODAX aggregates, at the surfactant concentration as low as 10 micromolar, whose Tm decreases monotonically with increasing DODAX concentration to attain the value for the ordinary vesicles. The data indicate that these aggregates are organized as bilayer-like structures.Fundação para a Ciência e a Tecnologia (FCT

Fluctuation theorem applied to Dictyostelium discoideum system

In this paper, we analyze the electrotactic movement of Dictyostelium discoideum from the viewpoint of non-equilibrium statistical mechanics. Because we can observe fluctuating behavior of cellular trajectories, we analyze the probability distribution of the trajectories with the aid of the fluctuation theorem. Recently, the validity of the fluctuation theorem was verified in a colloidal system, and it has also been applied to granular systems, turbulent systems and chemical oscillatory waves to investigate some of their statistical properties that are not yet completely understood. Noting that the fluctuation theorem is potentially applicable to cellular electrotaxis, here we employ it to help us obtain a phenomenological model of this biological system.Comment: 2 pages, to appear in J. Phys. Soc. Jp

Flebotomíneos (díptera: psychodidae) en la periferia de santarém (pa). Estratificacion horizontal y factores agravantes para la transmisión domiciliar de leishmaniosis

Phlebotominae collections were performed with CDC-type luminous traps, intradomiciliarily (dormitory) and peridomiciliarily (animal shelters) placed, triying to get breeding places in the outskirts of Santarem city in Brazil. Three outlying neighborhoods of the city, where there was registration of autochthonous cases of leishmaniasis, were chosen: Jutaí, Diamantino and St. André. 9.926 Phlebotominae individuals were captured, and they were distributed in 15 species. The most abundant species were L. longipalpis (59,72%) and L. carmelinoi (35,47%). In Jutaí neighborhood the largest amount of Phlebotominae was captured (6.031 specimens), followed by Diamantino neighborhood with (2.390 specimens) and St. André with (1.505 specimens). The major number of individuals was observed during the rainy season (5.377) than in the animal shelters (4.549). In the horizontal stratification there was a significant reduction (p = 0,02) in the Phlebotominae fauna as the residual forest increased.Fueron realizadas colectas de flebotomíneos por medio de trampas luminosas tipo CDC, colocadas intradomiciliarmente (dormitorio) y peridomiciliarmente (abrigos de animales) procurando los criaderos en barrios periféricos de la ciudad de Santarém, Brasil, haciendo la búsqueda en los lugares en donde hubiese registro de casos autóctonos de leishmaniosis, fueran seleccionadas, las siguientes áreas de trabajo: Jutaí, Diamantino y Sto. André. Se capturaron 9.926 flebotomíneos, distribuidos en 15 especies. Las especies más abundantes fueron L. longipalpis (59,72%) y L. carmelinoi (35,47%). En el barrio de Jutaí fue capturada la mayor cantidad de flebotomíneos (6.031), seguido por el barrio de Diamantino (2.390) y Sto. André (1.505). Hubo mayor densidad de individuos en los meses de la estación lluviosa. En la estratificación horizontal hubo reducción significativa (p = 0,02) de la fauna de flebotomíneos, en la medida en que aumentaba la separación de la floresta residu

CONDICIONANTES DAS POSIÇÕES SOCIAIS ROMANAS: UMA LEITURA A PARTIR DE POMPÉIA

The economic dynamism of Roman society in the first c. AD led to social diversity. Status and legal differences were linked to such variables as place, time and historical context. This paper studies both the economic and legal social spectrum through the exploration of inscriptions from Pompeii, emphasizing the role of popular strata

Avaliação temporal e espacial do balanço de energia na microbacia do córrego do Ipê, no município de Ilha Solteira face a mudança de uso do solo.

O objetivo deste trabalho foi analisar a variação espacial e temporal dos componentes que compõem o balanço de energia na microbacia do Córrego do Ipê, ao longo do período de 2003 a 2011 para o período seco, buscando identificar interferências com a mudança de uso da terra ocorrida com a entrada da cultura da cana de açúcar