5 research outputs found

    Generation of Vorticity and Velocity Dispersion by Orbit Crossing

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    We study the generation of vorticity and velocity dispersion by orbit crossing using cosmological numerical simulations, and calculate the backreaction of these effects on the evolution of large-scale density and velocity divergence power spectra. We use Delaunay tessellations to define the velocity field, showing that the power spectra of velocity divergence and vorticity measured in this way are unbiased and have better noise properties than for standard interpolation methods that deal with mass weighted velocities. We show that high resolution simulations are required to recover the correct large-scale vorticity power spectrum, while poor resolution can spuriously amplify its amplitude by more than one order of magnitude. We measure the scalar and vector modes of the stress tensor induced by orbit crossing using an adaptive technique, showing that its vector modes lead, when input into the vorticity evolution equation, to the same vorticity power spectrum obtained from the Delaunay method. We incorporate orbit crossing corrections to the evolution of large scale density and velocity fields in perturbation theory by using the measured stress tensor modes. We find that at large scales (k~0.1 h/Mpc) vector modes have very little effect in the density power spectrum, while scalar modes (velocity dispersion) can induce percent level corrections at z=0, particularly in the velocity divergence power spectrum. In addition, we show that the velocity power spectrum is smaller than predicted by linear theory until well into the nonlinear regime, with little contribution from virial velocities.Comment: 27 pages, 14 figures. v2: reorganization of the material, new appendix. Accepted by PR

    A disordered region retains the full protease inhibitor activity and the capacity to induce CD8+ T cells in vivo of the oral vaccine adjuvant U-Omp19

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    U-Omp19 is a bacterial protease inhibitor from Brucella abortus that inhibits gastrointestinal and lysosomal proteases, enhancing the half-life and immunogenicity of co-delivered antigens. U-Omp19 is a novel adjuvant that is in preclinical development with various vaccine candidates. However, the molecular mechanisms by which it exerts these functions and the structural elements responsible for these activities remain unknown. In this work, a structural, biochemical, and functional characterization of U-Omp19 is presented. Dynamic features of U-Omp19 in solution by NMR and the crystal structure of its C-terminal domain are described. The protein consists of a compact C-terminal beta-barrel domain and a flexible N-terminal domain. The latter domain behaves as an intrinsically disordered protein and retains the full protease inhibitor activity against pancreatic elastase, papain and pepsin. This domain also retains the capacity to induce CD8+ T cells in vivo of U-Omp19. This information may lead to future rationale vaccine designs using U-Omp19 as an adjuvant to deliver other proteins or peptides in oral formulations against infectious diseases, as well as to design strategies to incorporate modifications in its structure that may improve its adjuvanticity.Fil: Darriba, María Laura. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Pueblas Castro, Celeste. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Coria, Lorena M. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Bruno, Laura. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Cerutti, María Laura. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Chemes, Lucía B. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Cassataro, Juliana. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Pasquevich, Karina A. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Darriba, María Laura. Universidad Nacional de San Martín. Escuela de Bio y Nanotecnologías (EByN); Argentina.Fil: Pueblas Castro, Celeste. Universidad Nacional de San Martín. Escuela de Bio y Nanotecnologías (EByN); Argentina.Fil: Coria, Lorena M. Universidad Nacional de San Martín. Escuela de Bio y Nanotecnologías (EByN); Argentina.Fil: Bruno, Laura. Universidad Nacional de San Martín. Escuela de Bio y Nanotecnologías (EByN); Argentina.Fil: Cerutti, María Laura. Universidad Nacional de San Martín. Escuela de Bio y Nanotecnologías (EByN); Argentina.Fil: Chemes, Lucía B. Universidad Nacional de San Martín. Escuela de Bio y Nanotecnologías (EByN); Argentina.Fil: Cassataro, Juliana. Universidad Nacional de San Martín. Escuela de Bio y Nanotecnologías (EByN); Argentina.Fil: Pasquevich, Karina A. Universidad Nacional de San Martín. Escuela de Bio y Nanotecnologías (EByN); Argentina.Fil: Otero, Lisandro H. Fundación Instituto Leloir. Plataforma Argentina de Biología Estructural y Metabolómica. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Klinke, Sebastián. Fundación Instituto Leloir. Plataforma Argentina de Biología Estructural y Metabolómica. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Rasia, Rodolfo M. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario. Plataforma Argentina de Biología Estructural y Metabolómica; Argentina
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