Two interacting atoms in a cavity: exact solutions, entanglement and decoherence

We address the problem of two interacting atoms of different species inside a cavity and find the explicit solutions of the corresponding eigenvalues and eigenfunctions using a new invariant. This model encompasses various commonly used models. By way of example we obtain closed expressions for concurrence and purity as a function of time for the case where the cavity is prepared in a number state. We discuss the behaviour of these quantities and and their relative behaviour in the concurrence-purity plane.Comment: 10 pages, 3 figure

Antimicrobial, Antiproliferative and Proapoptotic Activities of Extract, Fractions and Isolated Compounds from the Stem of Erythroxylum caatingae Plowman

In the study, we have examined the antitumor and antimicrobial activities of the methanol extract, the fractions, a fraction of total alkaloids and two alkaloids isolated from the stem of Erythroxylum caatingae Plowman. All test fractions, except the hexane fractions, showed antimicrobial activity on gram-positive bacteria and fungi. The acetate: methanol (95:5), acetate, chloroform and hexane fractions show the highest cytotoxicity activity against the NCI-H292, HEp-2 and K562 cell lines using MTT. The absence of hemolysis in the erythrocytes of mice was observed in these fractions and 6β-Benzoyloxy-3α-(3,4,5- trimethoxybenzoyloxy) tropane (catuabine B). Staining with Annexin V-FITC and JC-1 was used to verify the mechanism of action of the compounds of E. caatingae that showed cytotoxicity less than 30 μg/mL in leukemic cells. After 48 h of incubation, we observed that the acetate: methanol (95:5), acetate, and chloroform fractions, as well as the catuabine B, increased in the number of cells in early apoptosis, from 53.0 to 74.8%. An analysis of the potential of the mitochondrial membrane by incorporation of JC-1 showed that most cells during incubation of the acetate: methanol (95:5) and acetate fractions (63.85 and 59.2%) were stained, suggesting the involvement of an intrinsic pathway of apoptosis

Platinum–Vanadium Oxide Nanotube Hybrids

The present contribution reports on the features of platinum-based systems supported on vanadium oxide nanotubes. The synthesis of nanotubes was carried out using a commercial vanadium pentoxide via hydrothermal route. The nanostructured hybrid materials were prepared by wet impregnation using two different platinum precursors. The formation of platinum nanoparticles was evaluated by applying distinct reduction procedures. All nanostructured samples were essentially analysed by X-ray diffraction and transmission electron microscopy. After reduction, transmission electron microscopy also made it possible to estimate particle size distribution and mean diameter calculations. It could be seen that all reduction procedures did not affect the nanostructure of the supports and that the formation of metallic nanoparticles is quite efficient with an indistinct distribution along the nanotubes. Nevertheless, the reduction procedure determined the diameter, dispersion and shape of the metallic particles. It could be concluded that the use of H2PtCl6 is more suitable and that the use of hydrogen as reducing agent leads to a nanomaterial with unagglomerated round-shaped metallic particles with mean size of 6–7 nm

Variação do teor de nitrogênio em ramos produtivos de caquizeiro.

O objetivo deste trabalho foi avaliar a resposta do caquizeiro (Diospyros kaki L.) à adubação nitrogenada. O experimento foi conduzido em um pomar comercial no município de Faxinal, Estado do Paraná, nas coordenadas geográfcas S 23º 57' 35", W51º 13' 34", altitude de 999 metros. A cultivar estudada foi "Giombo". Utilizou-se de 9 tratamentos, sendo uma testemunha sem aplicação de nitrogênio (N), e os demais resultante das épocas de aplicação de N (Maturação fisiológica dos frutos, início de poda, final de florescimento e em 15-12-06), combinadas com duas doses de N (80 e 160 kg/ha). O delineamento experimental foi o de blocos casualizados e 4 repetições. A parcela experimental foi constituída de 3 plantas, sendo a planta central usada para avaliação. A cada quarenta e cinco dias após o início da adubação, foram retirados aleatoriamente de cada tratamento oito ramos produtivos em diferentes pontos da planta. Na folha, os tratamentos IP e MF apresentaram os maiores teores de N na primavera e no verão, e uma diminuição significativa na fase final do ciclo antes da senescência e queda. Na folha e no ramo, todos os tratamentos resultaram em teor de N semelhante no final do ciclo. A época de aplicação, início de poda, foi a época que demonstrou menor variação de N, independentemente da dose

Ruthenium-europium configuration in the Eu2Ru2O7 pyrochlore

The magnetic and electronic properties of Eu2Ru2O7 are discussed in terms of the local ruthenium and europium coordination, electronic band structure calculations, and molecular orbital energy levels. A preliminary electronic structure was calculated within the local density approximation (LDA) and local spin density approximation taking in to account on-site Hubbard U (LSDA + U). The molecular orbital energy level diagrams have been used to interpret the Eu-Ru ligand spectrum and the ensuing magnetic properties. The orbital hybridizations and bonds are discussed. © 2015 AIP Publishing LLC

Hydrodynamic afterburner for the CGC at RHIC

Firstly, we give a short review about the hydrodynamic model and its application to the elliptic flow phenomena in relativistic heavy ion collisions. Secondly, we show the first approach to construct a unified model for the description of the dynamics in relativistic heavy ion collisions.Comment: 15 pages, 7 figures, invited talk presented at "Hot Quarks 2004", July 18-24, 2004, Taos Valley, NM, US