Lower Bounds for Pinning Lines by Balls

A line L is a transversal to a family F of convex objects in R^d if it intersects every member of F. In this paper we show that for every integer d>2 there exists a family of 2d-1 pairwise disjoint unit balls in R^d with the property that every subfamily of size 2d-2 admits a transversal, yet any line misses at least one member of the family. This answers a question of Danzer from 1957

Active-Site-Directed Inhibitors of Prolyl Oligopeptidase Abolish Its Conformational Dynamics

Deciphering conformational dynamics is crucial for understanding the biological functions of proteins and for designing compounds targeting them. In particular, providing an accurate description of microsecond–millisecond motions opens the opportunity for regulating protein–protein interactions (PPIs) by modulating the dynamics of one interacting partner. Here we analyzed the conformational dynamics of prolyl oligopeptidase (POP) and the effects of active-site-directed inhibitors on the dynamics. We used an integrated structural biology approach based on NMR spectroscopy and SAXS experiments complemented by MD simulations. We found that POP is in a slow equilibrium in solution between open and closed conformations, and that inhibitors effectively abolished this equilibrium by stabilizing the enzyme in the closed conformation.This work was supported by the Institute for Research in Biomedicine, MINECO-FEDER (Bio2013-40716-R, CTQ2013-48287 and CTQ2012-32183/BQU), and the Generalitat de Catalunya (XRB and Grup Consolidat 2014SGR521). AL has received funding from the Instituto de Salud Carlos III. PB acknowledges the Agence Nationale de la Recherche (SPINHD-ANR-CHEX-2011) and the ATIP-Avenir program for financial support. FHT’s fellowship is co-funded by the INSERM and the University of Copenhagen. Technical assistance from staff at the P12 beam line (EMBL/DESY) is acknowledged.Peer ReviewedPostprint (author's final draft

Analytical Solution for Wave Propagation in Stratified Acoustic/Porous Media. Part II: the 3D Case

We are interested in the modeling of wave propagation in an infinite bilayered acoustic/poroelastic media. We consider the biphasic Biot's model in the poroelastic layer. The first part is devoted to the calculation of analytical solution in two dimensions, thanks to Cagniard de Hoop method. In this second part we consider the 3D case

Attenuation of Mycobacterium species through direct and macrophage mediated pathway by unsymmetrical diaryl urea

Tuberculosis is a major threat for mankind and the emergence of resistance strain of Mycobacterium tuberculosis (Mtb) against first line antibiotics makes it lethal for human civilization. In this study, we have synthesized different diaryl urea derivatives targeting the inhibition of mycolic acid biosynthesis. Among the 39 synthesized molecules, compounds 46, 57, 58 and 86 showed MIC values ≤ 10 μg/ml against H37Rv and mc26030 strains. The best molecule with a methyl at ortho position of the first aromatic ring and prenyl group at the meta position of the second aromatic ring showed the MIC value of 5.2 μg/ml and 1 μg/ml against H37Rv and mc26030 respectively, with mammalian cytotoxicity of 163.4 μg/ml. The effective compounds showed selective inhibitory effect on mycolic acid (epoxy mycolate) biosynthesis in14C-radiolabelled assay. At the same time these molecules also executed their potent immunomodulatory activity by up-regulation of IFN-γ and IL-12 and down-regulation of IL-10.Fil: Velappan, Anand Babu. Sastra University; IndiaFil: Charan Raja, Mamilla R.. Sastra University; IndiaFil: Datta, Dhrubajyoti. Indian Institute of Science Education and Research Pune; IndiaFil: Tsai, Yi Ting. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Halloum, Iman. Université de Montpellier; Francia. Centre National de la Recherche Scientifique; FranciaFil: Wan, Baojie. University of Illinois; Estados UnidosFil: Kremer, Laurent. Université de Montpellier; Francia. Inserm; Francia. Centre National de la Recherche Scientifique; FranciaFil: Gramajo, Hugo Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Franzblau, Scott G.. University of Illinois; Estados UnidosFil: Kar Mahapatra, Santanu. Sastra University; IndiaFil: Debnath, Joy. Sastra University; Indi

Applications of the DFLU flux to systems of conservation laws

The DFLU numerical flux was introduced in order to solve hyperbolic scalar conservation laws with a flux function discontinuous in space. We show how this flux can be used to solve systems of conservation laws. The obtained numerical flux is very close to a Godunov flux. As an example we consider a system modeling polymer flooding in oil reservoir engineering

Anomalous magnetic field dependence of the thermodynamic transition line in the isotropic superconductor (K,Ba)Bi03

Thermodynamic (specific heat, reversible magnetization, tunneling spectroscopy) and transport measurements have been performed on high quality (K,Ba)BiO$_3$ single crystals. The temperature dependence of the magnetic field $H_{Cp}$ corresponding to the onset of the specific heat anomaly presents a clear positive curvature. $H_{Cp}$ is significantly smaller than the field $H_\Delta$ for which the superconducting gap vanishes but is closely related to the irreversibility line deduced from transport data. Moreover, the temperature dependence of the reversible magnetization present a strong deviation from the Ginzburg--Landau theory emphasazing the peculiar nature of the superconducting transition in this material.Comment: 4 pages, 4 figures, 28 reference

An Upper Bound on the Average Size of Silhouettes

It is a widely observed phenomenon in computer graphics that the size of the silhouette of a polyhedron is much smaller than the size of the whole polyhedron. This paper provides, for the first time, theoretical evidence supporting this for a large class of objects, namely for polyhedra that approximate surfaces in some reasonable way; the surfaces may be non-convex and non-differentiable and they may have boundaries. We prove that such polyhedra have silhouettes of expected size $O(\sqrt{n})$ where the average is taken over all points of view and n is the complexity of the polyhedron