650 research outputs found

    Aging promotes pro-fibrotic matrix production and increases fibrocyte recruitment during acute lung injury.

    Get PDF
    Fibrotic lung diseases increase with age. Previously we determined that senescence increases tissue expression of fibronectin EDA (Fn-EDA) and decreases fibroblast expression of Thy-1, and that fibrocytes contribute to fibrosis following bleomycin-induced lung injury in mice. In this study we hypothesized that fibroblasts lacking Thy-1 expression produce an extracellular matrix that promotes fibrocyte retention and myofibroblast transdifferentiation, thereby promoting fibrogenesis. Young and old mice were treated with bleomycin intratracheally; fibrocytes in the bone marrow, blood, and lungs were quantified, and lung fibroblast Thy-1 expression assessed. Bone marrow-derived fibrocytes were cultured on matrices derived from Thy-1(+) or Thy-1(-) fibroblasts ± the pro-fibrotic cytokine TGFβ1. Older mice had more fibrocytes in their bone marrows at baseline and more fibrocytes in their lungs following bleomycin treatment. In parallel, lung fibroblasts in older mice had lower expression of Thy-1 at baseline that increased transiently 7 days after bleomycin treatment but then rapidly waned such that 14 days after bleomycin treatment Thy-1 expression was again markedly lower. Fibrocytes cultured on matrices derived from Thy-1(-) fibroblasts + TGFβ1 had increased gene expression for collagen type 1, fibronectin, Fn-EDA, and α-smooth muscle actin. In parallel, whereas the matrices derived from Thy-1(-) fibroblasts stimulated phosphorylation of Akt in cultured fibrocytes, the matrices derived from Thy-1(+) fibroblasts induced apoptosis. These findings suggest that senescence increases fibrocyte recruitment to the lung following injury and that loss of Thy-1 expression by lung fibroblasts promotes fibrocyte retention and myofibroblast trans-differentiation that renders the "aging lung" susceptible to fibrosis

    CPDW Project. Assessment of Cytotoxicological Potential of Products in Contact with Drinking Water.

    Get PDF
    The investigations described in this report were conducted as part of the European Project "Development of Harmonised tests to be used in the European Approval Scheme (EAS) concerning Construction Products in contact with Drinking Water (CPDW)", under Contract no. EVK1-CT2000-00052. This project is financially supported by the European Commission, the national authorities of Denmark, France, Germany, Portugal and the United Kingdom and the material suppliers in these countries and Europe, respectively. Work Package 2 concerned the cytotoxicity properties of materials of this project. The institutes participating in the investigations and discussions in this work package are listed below.JRC.DDG.H-Institute for environment and sustainability (Ispra

    Why Don't We Have a Covariant Superstring Field Theory?

    Full text link
    This talk deals with the old problem of formulatingn a covariant quantum theory of superstrings, ``covariant'' here meaning having manifest Lorentz symmetry and supersymmetry. The advantages and disadvantages of several quantization methods are reviewed. Special emphasis is put on the approaches using twistorial variables, and the algebraic structures of these. Some unsolved problems are identified.Comment: 5 pages, Goteborg-ITP-94-24, plain te

    Constraints on the pMSSM from searches for squarks and gluinos by ATLAS

    Get PDF
    We study the impact of the jets and missing transverse momentum SUSY analyses of the ATLAS experiment on the phenomenological MSSM (pMSSM). We investigate sets of SUSY models with a flat and logarithmic prior in the SUSY mass scale and a mass range up to 1 and 3 TeV, respectively. These models were found previously in the study 'Supersymmetry without Prejudice'. Removing models with long-lived SUSY particles, we show that 99% of 20000 randomly generated pMSSM model points with a flat prior and 87% for a logarithmic prior are excluded by the ATLAS results. For models with squarks and gluinos below 600 GeV all models of the pMSSM grid are excluded. We identify SUSY spectra where the current ATLAS search strategy is less sensitive and propose extensions to the inclusive jets search channel

    Discrete-time classical and quantum Markovian evolutions: Maximum entropy problems on path space

    Full text link
    The theory of Schroedinger bridges for diffusion processes is extended to classical and quantum discrete-time Markovian evolutions. The solution of the path space maximum entropy problems is obtained from the a priori model in both cases via a suitable multiplicative functional transformation. In the quantum case, nonequilibrium time reversal of quantum channels is discussed and space-time harmonic processes are introduced.Comment: 34 page

    Recent progress in random metric theory and its applications to conditional risk measures

    Full text link
    The purpose of this paper is to give a selective survey on recent progress in random metric theory and its applications to conditional risk measures. This paper includes eight sections. Section 1 is a longer introduction, which gives a brief introduction to random metric theory, risk measures and conditional risk measures. Section 2 gives the central framework in random metric theory, topological structures, important examples, the notions of a random conjugate space and the Hahn-Banach theorems for random linear functionals. Section 3 gives several important representation theorems for random conjugate spaces. Section 4 gives characterizations for a complete random normed module to be random reflexive. Section 5 gives hyperplane separation theorems currently available in random locally convex modules. Section 6 gives the theory of random duality with respect to the locally L0L^{0}-convex topology and in particular a characterization for a locally L0L^{0}-convex module to be L0L^{0}-pre-barreled. Section 7 gives some basic results on L0L^{0}-convex analysis together with some applications to conditional risk measures. Finally, Section 8 is devoted to extensions of conditional convex risk measures, which shows that every representable LL^{\infty}-type of conditional convex risk measure and every continuous LpL^{p}-type of convex conditional risk measure (1p<+1\leq p<+\infty) can be extended to an LF(E)L^{\infty}_{\cal F}({\cal E})-type of σϵ,λ(LF(E),LF1(E))\sigma_{\epsilon,\lambda}(L^{\infty}_{\cal F}({\cal E}), L^{1}_{\cal F}({\cal E}))-lower semicontinuous conditional convex risk measure and an LFp(E)L^{p}_{\cal F}({\cal E})-type of Tϵ,λ{\cal T}_{\epsilon,\lambda}-continuous conditional convex risk measure (1p<+1\leq p<+\infty), respectively.Comment: 37 page

    String-Based Methods in Perturbative Gravity

    Full text link
    String theory implies a relatively modest growth in computational complexity for perturbative gravity calculations as compared to gauge theory calculations, contrary to field theory expectations. An explicit string-based calculation, which would be extremely difficult using conventional techniques, is presented to illustrate this.Comment: 14 pages (including figure), IASSNS-HEP-93-3

    WASP-157b, a Transiting Hot Jupiter Observed with K2

    Get PDF
    We announce the discovery of the transiting hot Jupiter WASP-157b in a 3.95-d orbit around a V = 12.9 G2 main-sequence star. This moderately inflated planet has a Saturn-like density with a mass of 0.57±0.100.57 \pm 0.10 MJup_{\rm Jup} and a radius of 1.06±0.051.06 \pm 0.05 RJup_{\rm Jup}. We do not detect any rotational or phase-curve modulations, nor the secondary eclipse, with conservative semi-amplitude upper limits of 250 and 20 ppm, respectively.Comment: 6 pages, 5 figures and 4 tables. Accepted for publication in PAS
    corecore