302 research outputs found

    Anti-inflammatory, antinociceptive, and antipyretic effects of methanol extract of Cariniana rubra stem bark in animal models

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    Schmeda-Hirschmann, G (Schmeda-Hirschmann, Guillermo) Univ Talca, IQRN, Talca, ChileCariniana rubra Miers (Lecythidaceae), popularly known as "jequitiba-vermelho", is a large Brazilian tree whose bark is used in infusion and decoction for the treatment of inflammatory conditions. This study aims to assess the anti-inflammatory, antinociceptive, and antipyretic effects of Cariniana rubra methanolic stem bark extract (EMCr) using experimental animals. Anti-inflammatory activity of EMCr was tested on carrageenan and dextran-induced rat paw edema, carrageenan-induced pleurisy in rats and acetic acid-increase vascular permeability in mice. Antinociceptive and antipyretic activities were evaluated using acetic acid-induced writhing, formalin and hot-plate tests in mice, as well as brewer's yeast-induced pyrexia in rats. The extract inhibitied carrageenan and dextran-induced edema, reduced exudate volume and leukocyte migration on the carrageenan-induced pleurisy and on the vascular permeability increase induced by acetic acid. The EMCr inhibited nociception on the acetic acid-induced writhing and in the second phase of formalin test, and decreased rectal temperature. It was, however, inactive against thermal nociception. Phytochemical analysis with EMCr showed the occurrence of saponins, triterpenes, sterols and phenolic compounds. Phytosterols (beta-sitosterol, stigmasterol), pentacyclic triterpenes (alpha- and beta-amyrin as a mixture), arjunolic acid, a phytosterol glycoside (sitosterol 3-O-beta-D-glucopyranoside), and triterpenoid saponins (28-beta-glucopyranosyl-23-O-acetyl arjunolic acid; 3-O-beta-glucopyranosyl arjunolic acid and 28-O-[alpha-L-Rhamnopyranosyl-(1 -> 2)-beta-glucopyranosyl]-23-O-acetyl arjunolic acid) were the main identified compounds. It can be presumed that EMCr caused their effects by inhibiting the liberation and/or action of different inflammatory mediators. These findings support the traditional use of Cariniana rubra preparations to treat inflammation

    Fitting the integrated Spectral Energy Distributions of Galaxies

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    Fitting the spectral energy distributions (SEDs) of galaxies is an almost universally used technique that has matured significantly in the last decade. Model predictions and fitting procedures have improved significantly over this time, attempting to keep up with the vastly increased volume and quality of available data. We review here the field of SED fitting, describing the modelling of ultraviolet to infrared galaxy SEDs, the creation of multiwavelength data sets, and the methods used to fit model SEDs to observed galaxy data sets. We touch upon the achievements and challenges in the major ingredients of SED fitting, with a special emphasis on describing the interplay between the quality of the available data, the quality of the available models, and the best fitting technique to use in order to obtain a realistic measurement as well as realistic uncertainties. We conclude that SED fitting can be used effectively to derive a range of physical properties of galaxies, such as redshift, stellar masses, star formation rates, dust masses, and metallicities, with care taken not to over-interpret the available data. Yet there still exist many issues such as estimating the age of the oldest stars in a galaxy, finer details ofdust properties and dust-star geometry, and the influences of poorly understood, luminous stellar types and phases. The challenge for the coming years will be to improve both the models and the observational data sets to resolve these uncertainties. The present review will be made available on an interactive, moderated web page (sedfitting.org), where the community can access and change the text. The intention is to expand the text and keep it up to date over the coming years.Comment: 54 pages, 26 figures, Accepted for publication in Astrophysics & Space Scienc

    Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

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    This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio

    Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS

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    The chi_b(nP) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb^-1, these states are reconstructed through their radiative decays to Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes. This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table, corrected author list, matches final version in Physical Review Letter

    Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

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    We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final version to appear in Physics Letters
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