Quantum evolution of scalar fields in Robertson-Walker space-time

We study the $\lambda \phi^4$ field theory in a flat Robertson-Walker space-time using the functional Sch\"odinger picture. We introduce a simple Gaussian approximation to analyze the time evolution of pure states and we establish the renormalizability of the approximation. We also show that the energy-momentum tensor in this approximation is finite once we consider the usual mass and coupling constant renormalizations.Comment: Revtex file, 19 pages, no figures. Compressed ps version available at http://phenom.physics.wisc.edu/pub/preprints/1995/madph-95-912.ps.Z or at ftp://phenom.physics.wisc.edu/pub/preprints/1995/madph-95-912.ps.

Suplementação fosfatada para bovinos de corte em campos naturais da serra do sudeste, Rio Grande do Sul.

SUPLEMENTAÇÃO FOSTATADA PARA BOVINOS DE CORTE EM CAMPOS NATURAIS DA SERRA DO SUDESTE, RIO GRANDE DO SUL - Nos campos naturais da Região agroecológica Serra do Sudeste, foi conduzido um estudo abrangente sobre a influência de fatores de solo e de clima sobre a dinâmica estacional da disponibilidade de minerais na cadeia solo-pastagem-animal. O estudo foi realizado em duas propriedades rurais no 2º (Área 1, Fazenda Esperança) e no 4º (Área 2, Fazenda São Thomaz) sub-distritos do município de Piratini, RS, cujas características de solo, da vegetação e topográficas são representativas da Região. A interpretação dos teores minerais no solo indicou que apenas o fósforo e o sódio são os elementos em deficiência. O estudo revelou que os solos da região apresentam baixos teores de fósforo durante o ano todo, sendo menores no inverno e maiores no verão. Os teores de fósforo na vegetação do campo natural são insuficientes para suprir as exigências nutricionais dos animais em pastejo. Assim sendo, os teores de fósforo no soro de sangue dos animais em pastejo estão abaixo do limite de normalidade no verão, outono e inverno; na primavera encontra-se no limite da normalidade para novilhas (8,0 mg/100 ml). Como foi evidente a deficiência de fósforo para os animais na maior parte do ano, recomenda-se a suplementação com fósforo durante todo o ano. Em função dos baixos teores de sódio no solo e na forragem, o fornecimento de misturas minerais contendo cloreto de sódio + fósforo é imprescindível. Ou então misturas com sais proteinados + fósforo, para ajudar a utilização deste nutriente em períodos de deficiência de proteína, como no inverno.bitstream/item/31322/1/comunicado-170.pd

Pastagens em Terras Baixas.

bitstream/item/84466/1/Digitalizar0061.pd

Caracterização agronômica de paspalum em terras baixas do litoral sul do Rio Grande do Sul.

bitstream/item/30394/1/boletim-61.pd

Endometriosis: A Rare Cause of Large Bowel Obstruction.

Large bowel obstruction can result in significant morbidity and mortality, especially in cases of acute complete obstruction. There are many possible causes, the most common in adults being colorectal cancer. Endometriosis is a benign disease, and the most affected extragenital location is the bowel, especially the rectosigmoid junction. However, transmural involvement and acute occlusion are very rare events. We report an exceptional case of acute large bowel obstruction as the initial presentation of endometriosis. The differential diagnosis of colorectal carcinoma may be challenging, and this case emphasizes the need to consider intestinal endometriosis in females at a fertile age presenting with gastrointestinal symptoms and an intestinal mass causing complete large bowel obstruction.info:eu-repo/semantics/publishedVersio

A Rapidly Spinning Black Hole Powers the Einstein Cross

Observations over the past 20 years have revealed a strong relationship between the properties of the supermassive black hole (SMBH) lying at the center of a galaxy and the host galaxy itself. The magnitude of the spin of the black hole will play a key role in determining the nature of this relationship. To date, direct estimates of black hole spin have been restricted to the local Universe. Herein, we present the results of an analysis of $\sim$ 0.5 Ms of archival Chandra observations of the gravitationally lensed quasar Q 2237+305 (aka the "Einstein-cross"), lying at a redshift of z = 1.695. The boost in flux provided by the gravitational lens allows constraints to be placed on the spin of a black hole at such high redshift for the first time. Utilizing state of the art relativistic disk reflection models, the black hole is found to have a spin of $a_* = 0.74^{+0.06}_{-0.03}$ at the 90% confidence level. Placing a lower limit on the spin, we find $a_* \geq 0.65$ (4$\sigma$). The high value of the spin for the $\rm \sim 10^9~M_{\odot}$ black hole in Q 2237+305 lends further support to the coherent accretion scenario for black hole growth. This is the most distant black hole for which the spin has been directly constrained to date.Comment: 5 pages, 3 figures, 1 table, formatted using emulateapj.cls. Accepted for publication in ApJ

Initial measurements of black hole spin in GX 339-4 from Suzaku spectroscopy

We report on a deep Suzaku observation of the stellar-mass black hole GX 339-4 in outburst. A clear, strong, relativistically shaped iron emission line from the inner accretion disk is observed. The broadband disk reflection spectrum revealed is one of the most sensitive yet obtained from an accreting black hole. We fit the Suzaku spectra with a physically motivated disk reflection model, blurred by a new relativistic line function in which the black hole spin parameter is a variable. This procedure yielded a black hole spin parameter of a p. Joint modeling of these Suzaku spectra and prior XMM-Newton spectra obtained in two different 0.89 +/- 0.04 outburst phases yields a spin parameter of a = 0.93 +/- 0.01. The degree of consistency between these results suggests that disk reflection models allow for spin measurements that are not strongly biased by scattering effects. We suggest that the best value of the black hole spin parameter is a = 0.93 +/- 0.01 (statistical) +/- 0.04 (systematic). Although preliminary, these results represent the first direct measurement of nonzero spin in a stellar-mass black hole using relativistic line modeling