71 research outputs found

    Security devices based on liquid crystals doped with a colour dye

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    Liquid crystal properties make them useful for the development of security devices in applications of authentication and detection of fakes. Induced orientation of liquid crystal molecules and birefringence are the two main properties used in security devices. Employing liquid crystal and dichroic colorants, we have developed devices that show, with the aid of a polarizer, multiple images on each side of the device. Rubbed polyimide is used as alignment layer on each substrate of the LC cell. By rubbing the polyimide in different directions in each substrate it is possible to create any kind of symbols, drawings or motifs with a greyscale; the more complex the created device is, the more difficult is to fake it. To identify the motifs it is necessary to use polarized light. Depending on whether the polarizer is located in front of the LC cell or behind it, different motifs from one or the other substrate are shown. The effect arises from the dopant colour dye added to the liquid crystal, the induced orientation and the twist structure. In practice, a grazing reflection on a dielectric surface is polarized enough to see the effect. Any LC flat panel display can obviously be used as backlight as well

    Neoplasias orales en el perro y en el gato

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    En el presente trabajo se revisan las principales neoplasias orales del perro y del gato, de acuerdo con la experiencia clínica de los autores. Para cada neoplasia se discute la etiología y el cuadro clínico, y los autores recomiendan unas determinadas pautas de diagnóstico y tratamiento.In this paper the most frequent neoplasias of the oral cavity of the dog and cat are described and discussed according to the clinical experience of the autbors. For each neoplasia a diagnostic and therapeutic approach is proposed

    Synthesis and Properties of High Tilted Antiferroelectric Esters with Partially Fluorinated Alkoxyalkoxy Terminal Chains

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    Novel chiral esters with partially fluorinated alkoxyalkoxy terminal chains are described. Their phase transition temperatures, enthalpies, and electrooptical properties are reported. A helical pitch in pure compounds and their mixtures based on selective reflection of light is also characterized

    Cymantrene–Triazole "Click" Products: Structural Characterization and Electrochemical Properties

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    We report the first known examples of triazole-derivatized cymantrene complexes (η5-[4-substituted triazol-1-yl]cyclopentadienyl)tricarbonylmanganese(I), obtained via a “click” chemical synthesis, bearing a phenyl, 3-aminophenyl, or 4-aminophenyl moiety at the 4-position of the triazole ring. Structural characterization data using multinuclear NMR, UV–vis, ATR-IR, and mass spectrometric methods are provided, as well as crystallographic data for (η5-[4-phenyltriazol-1-yl]cyclopentadienyl)tricarbonylmanganese(I) and (η5-[4-(3-aminophenyl)triazol-1-yl]cyclopentadienyl)tricarbonylmanganese(I). Cyclic voltammetric characterization of the redox behavior of each of the three cymantrene–triazole complexes is presented together with digital simulations, in situ infrared spectroelectrochemistry, and DFT calculations to extract the associated kinetic and thermodynamic parameters. The trypanocidal activity of each cymantrene–triazole complex is also examined, and these complexes are found to be more active than cymantrene alone

    The chaperonin CCT controls T cell receptor-driven 3D configuration of centrioles

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    T lymphocyte activation requires the formation of immune synapses (IS) with antigen-presenting cells. The dynamics of membrane receptors, signaling scaffolds, microfilaments, and microtubules at the IS determine the potency of T cell activation and subsequent immune response. Here, we show that the cytosolic chaperonin CCT (chaperonin-containing TCP1) controls the changes in reciprocal orientation of the centrioles and polarization of the tubulin dynamics induced by T cell receptor in T lymphocytes forming an IS. CCT also controls the mitochondrial ultrastructure and the metabolic status of T cells, regulating the de novo synthesis of tubulin as well as posttranslational modifications (poly-glutamylation, acetylation, ?1 and ?2) of ??-tubulin heterodimers, fine-tuning tubulin dynamics. These changes ultimately determine the function and organization of the centrioles, as shown by three-dimensional reconstruction of resting and stimulated primary T cells using cryo-soft x-ray tomography. Through this mechanism, CCT governs T cell activation and polarity.Cryo-SXT work was supported by ALBA Synchrotron standard proposals 2015021148 and 2016021638 to F.J.C., N.B.M.-C., and J.M.V. This study was supported by grants SAF2017-82886-R (to F.S.-M.), PID2019-105872GB-I00/AEI/10.13039/501100011033 (AEI/FEDER, UE), BFU2016-75984 (to J.M.V.), and BIO2015-67580-P and PGC2018-097019-B-I00 (to J.V.) from the Spanish Ministry of Economy and Competitiveness (MINECO), grants INFLAMUNE-S2017/BMD-23671 (to F.S.-M.) and P2018/NMT-4389 (to J.M.V.) from the Comunidad de Madrid, ERC-2011-AdG 294340-GENTRIS (to F.S.-M.), a 2019 grant from the Ramón Areces Foundation “Ciencias de la Vida y la Salud” and a 2018 grant from Ayudas Fundación BBVA a Equipos de Investigación Científica (to F.S.-M.), and grants PRB3 (IPT17/0019-ISCIII-SGEFI/ERDF), the Fundació Marató TV3 (grant 122/C/2015), and “La Caixa” Banking Foundation (HR17-00016 to FSM and HR17-00247 to J.V.). D.T. is supported by a PhD fellowship from La Caixa Foundation. Work in the Vernos lab was supported by the grant CSD2006-00023 from the Spanish Ministry of Science and Innovation and grants BFU2012-37163 and BFU2015-68726-P from the Spanish Ministry of Economy and Competitiveness. The CRG acknowledges support of the Spanish Ministry of Science and Innovation to the EMBL partnership, the Centro de Excelencia Severo Ochoa, and the CERCA Programme/Generalitat de Catalunya. CIBER Cardiovascular (Fondo de Investigación Sanitaria del Instituto de Salud Carlos III and co-funding by Fondo Europeo de Desarrollo Regional FEDER). The Centro Nacional de Investigaciones Cardiovasculares (CNIC) is supported by the Spanish Ministry of Economy and Competitiveness (MINECO) and the Pro-CNIC Foundation and is a Severo Ochoa Center of Excellence (MINECO award SEV-2015- 0505). The Centro Nacional de Biotecnología (CNB) is a Severo Ochoa Center of Excellence (MINECO award SEV 2017-0712). Funding agencies have not intervened in the design of the studies, with no copyright over the stud
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