Multi-technique approach to rockfall monitoring in the Montserrat massif (Catalonia, NE Spain)

Montserrat Mountain is located near Barcelona in Catalonia, in the northeast of Spain, and its massif is formed by conglomerate interleaved by siltstone/sandstone with steep slopes very prone to rockfalls. The increasing number of visitors in the monastery area, reaching 2.4 million per year, has highlighted the risk derived from rockfalls for this building area and also for the terrestrial accesses, both roads and the rack railway. A risk mitigation plan has been launched, and its first phase during 2014-2016 has been focused largely on testing several monitoring techniques for their later implementation. The results of the pilot tests, performed as a development from previous sparse experiences and data, are presented together with the first insights obtained. These tests combine four monitoring techniques under different conditions of continuity in space and time domains, which are: displacement monitoring with Ground-based Synthetic Aperture Radar and characterization at slope scale, with an extremely non-uniform atmospheric phase screen due to the stepped topography and atmosphere stratification; Terrestrial Laser Scanner surveys quantifying the frequency of small or even previously unnoticed rockfalls, and monitoring rock block centimetre scale displacements; the monitoring of rock joints implemented through a wireless sensor network with an ad hoc design of ZigBee loggers developed by ICGC; and, finally, monitoring singular rock needles with Total Station.Peer ReviewedPostprint (author's final draft

The β‐1,3‐glucanosyltransferases (Gels) affect the structure of the rice blast fungal cell wall during appressorium‐mediated plant infection

[EN] The fungal wall is pivotal for cell shape and function, and in interfacial protection during host infection and environmental challenge. Here, we provide the first description of the carbohydrate composition and structure of the cell wall of the rice blast fungus Magnaporthe oryzae. We focus on the family of glucan elongation proteins (Gels) and characterize five putative β-1,3-glucan glucanosyltransferases that each carry the Glycoside Hydrolase 72 signature. We generated targeted deletion mutants of all Gel isoforms, that is, the GH72+, which carry a putative carbohydrate-binding module, and the GH72− Gels, without this motif. We reveal that M. oryzae GH72+ GELs are expressed in spores and during both infective and vegetative growth, but each individual Gel enzymes are dispensable for pathogenicity. Further, we demonstrated that a Δgel1Δgel3Δgel4 null mutant has a modified cell wall in which 1,3-glucans have a higher degree of polymerization and are less branched than the wild-type strain. The mutant showed significant differences in global patterns of gene expression, a hyper-branching phenotype and no sporulation, and thus was unable to cause rice blast lesions (except via wounded tissues). We conclude that Gel proteins play significant roles in structural modification of the fungal cell wall during appressorium-mediated plant infection.SIWe acknowledge BBSRC grant BB/J008923/1

Influence of the calibration on experimental UV index at a midlatitude site, Granada (Spain)

The ultraviolet index (UVI) is the most commonly used variable to inform about the level and potential harmful effect of ultraviolet (UV) radiation reaching the Earth's surface. This variable is derived from the output signal of UV radiometers applying conversion factors from calibration methods. This paper focused on the influence of the use of two of these methods (called one-step and two-steps methods) on the experimental UVI measured by a YES UVB-1 radiometer located in a midlatitude station, Granada (Spain) for the period 2006–2009. In addition, it also analyzes the deviation from the UVI values obtained when the manufacturer's calibration factors are applied. For this goal, a detailed characterization of the UVB-1 radiometer from the first Spanish calibration campaign of broadband UV radiometers at the "El Arenosillo" INTA station in 2007 was used. In addition, modeled UVI data derived from the LibRadtran/UVSPEC radiative transfer code are compared with the experimental values recorded at Granada for cloud-free conditions. Absolute mean differences between measured and modeled UVI data at Granada were around 5% using the one-step and two-steps calibration methods, indicating an excellent performance of these two techniques for obtaining UVI data from the UVB-1 radiometer. Conversely, the application of the manufacture's calibration factor produced a large overestimation (~14%) of the UVI values, generating unreliable alarming high UVI data in summer. Thus, the number of days with an extreme erythemal risk (UVI higher than 10) increased up to 46% between May and September at Granada. This percentage reduced to a more reliable value of 3% when the conversion factors obtained with the two-steps calibration method are used. These results evidence the need for a sound calibration of the broadband UV instruments in order to obtain reliable measurements.This work was partially supported by the Andalusian Regional Government through projects P08-RNM-3568 and P10-RNM-6299, the Spanish Ministry of Science and Technology through projects CGL2010-18782 and CSD2007-00067

Sequential extraction of hemicelluloses by subcritical water improves saccharification of hybrid aspen wood grown in greenhouse and field conditions

Fast growing hardwoods are one of the major renewable resources available to produce bio-based materials, platform chemicals and biofuels. However, the industrial processing of lignocellulosic biomass is hindered by the complex molecular structure of the cell wall components and their supramolecular organization. This highlights the necessity of improving green processing strategies to enhance biomass conversion to valuable products from industrial wood production species. In the present study, we implemented a hydrothermal step by sequential subcritical water (SW) in aspen wood prior to saccharification and validated the process for trees grown in greenhouse and field conditions. Subcritical water enables extraction of non-cellulosic cell wall polysaccharides in native polymeric form. A major part of the pectic fraction was easily extracted within the first 10 min, while acetylated xylan was enriched in the subsequent extracts after 20- and 30-min rounds. Prolonged extraction (above 60 min) resulted in partial deacetylation and a reduction of the molar mass of xylan. The analysis of the residues enriched with cellulose and lignin showed several micromorphological changes caused by subcritical water treatment, such as an increased porosity, a loosening of the fibre matrix and a decrease in the macrofibrillar dimensions. These morphological and molecular changes in the organization of cell wall polymers after SW treatment significantly enhanced saccharification yields compared to those of non-treated aspen wood chips from both field and greenhouse conditions. Our study demonstrates that SW can be implemented as pretreatment prior to saccharification reducing the requirements for chemical acid pretreatments. This process enables the extraction of native non-cellulosic cell wall polymers for potential material applications and promotes the subsequent biochemical conversion of the residual biomass into fermentable sugars and platform chemicals in future biorefineries

High-pressure Raman scattering in wurtzite indium nitride

Copyright (2011) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.We perform Raman-scattering measurements at high hydrostatic pressures on c-face and a-face InN layers to investigate the high-pressure behavior of the zone-center optical phonons of wurtzite InN. Linear pressure coefficients and mode Grneisen parameters are obtained, and the experimental results are compared with theoretical values obtained from ab initio lattice-dynamical calculations. Good agreement is found between the experimental and calculated results. © 2011 American Institute of Physics.Work supported by the Spanish MICINN (Projects MAT2010-16116, MAT2008-06873-C02-02, MAT2010-21270-C04-04, and CSD2007-00045), the Catalan Government (BE-DG 2009), and the Spanish Council for Research (PIE2009-CSIC).Ibanez, J.; Manjón Herrera, FJ.; Segura, A.; Oliva, R.; Cusco, R.; Vilaplana Cerda, RI.; Yamaguchi, T.... (2011). High-pressure Raman scattering in wurtzite indium nitride. Applied Physics Letters. 99:119081-119083. https://doi.org/10.1063/1.3609327S11908111908399Veal, T., McConville, C., & Schaff, W. (Eds.). (2009). Indium Nitride and Related Alloys. doi:10.1201/9781420078107Gallinat, C. S., Koblmüller, G., Brown, J. S., Bernardis, S., Speck, J. S., Chern, G. D., … Wraback, M. (2006). In-polar InN grown by plasma-assisted molecular beam epitaxy. Applied Physics Letters, 89(3), 032109. doi:10.1063/1.2234274Li, S. X., Wu, J., Haller, E. E., Walukiewicz, W., Shan, W., Lu, H., & Schaff, W. J. (2003). Hydrostatic pressure dependence of the fundamental bandgap of InN and In-rich group III nitride alloys. Applied Physics Letters, 83(24), 4963-4965. doi:10.1063/1.1633681Gorczyca, I., Plesiewicz, J., Dmowski, L., Suski, T., Christensen, N. E., Svane, A., … Speck, J. S. (2008). Electronic structure and effective masses of InN under pressure. Journal of Applied Physics, 104(1), 013704. doi:10.1063/1.2953094Domènech-Amador, N., Cuscó, R., Artús, L., Yamaguchi, T., & Nanishi, Y. (2011). Raman scattering study of anharmonic phonon decay in InN. Physical Review B, 83(24). doi:10.1103/physrevb.83.245203Serrano, J., Bosak, A., Krisch, M., Manjón, F. J., Romero, A. H., Garro, N., … Kuball, M. (2011). InN Thin Film Lattice Dynamics by Grazing Incidence Inelastic X-Ray Scattering. Physical Review Letters, 106(20). doi:10.1103/physrevlett.106.205501Pinquier, C., Demangeot, F., Frandon, J., Pomeroy, J. W., Kuball, M., Hubel, H., … Gil, B. (2004). Raman scattering in hexagonal InN under high pressure. Physical Review B, 70(11). doi:10.1103/physrevb.70.113202Pinquier, C., Demangeot, F., Frandon, J., Chervin, J.-C., Polian, A., Couzinet, B., … Maleyre, B. (2006). Raman scattering study of wurtzite and rocksalt InN under high pressure. Physical Review B, 73(11). doi:10.1103/physrevb.73.115211Yao, L. D., Luo, S. D., Shen, X., You, S. J., Yang, L. X., Zhang, S. J., … Xie, S. S. (2010). Structural stability and Raman scattering of InN nanowires under high pressure. Journal of Materials Research, 25(12), 2330-2335. doi:10.1557/jmr.2010.0290Cuscó, R., Ibáñez, J., Alarcón-Lladó, E., Artús, L., Yamaguchi, T., & Nanishi, Y. (2009). Raman scattering study of the long-wavelength longitudinal-optical-phonon–plasmon coupled modes in high-mobility InN layers. Physical Review B, 79(15). doi:10.1103/physrevb.79.155210Wagner, J.-M., & Bechstedt, F. (2003). First-principles study of phonon-mode softening under pressure: the case of GaN and AlN. physica status solidi (b), 235(2), 464-469. doi:10.1002/pssb.200301603Weinstein, B. A. (1977). Phonon dispersion of zinc chalcogenides under extreme pressure and the metallic transformation. Solid State Communications, 24(9), 595-598. doi:10.1016/0038-1098(77)90369-6Yakovenko, E. V., Gauthier, M., & Polian, A. (2004). High-pressure behavior of the bond-bending mode of AIN. Journal of Experimental and Theoretical Physics, 98(5), 981-985. doi:10.1134/1.1767565Reparaz, J. S., Muniz, L. R., Wagner, M. R., Goñi, A. R., Alonso, M. I., Hoffmann, A., & Meyer, B. K. (2010). Reduction of the transverse effective charge of optical phonons in ZnO under pressure. Applied Physics Letters, 96(23), 231906. doi:10.1063/1.3447798Perlin, P., Jauberthie-Carillon, C., Itie, J. P., San Miguel, A., Grzegory, I., & Polian, A. (1992). Raman scattering and x-ray-absorption spectroscopy in gallium nitride under high pressure. Physical Review B, 45(1), 83-89. doi:10.1103/physrevb.45.83Manjón, F. J., Errandonea, D., Romero, A. H., Garro, N., Serrano, J., & Kuball, M. (2008). Lattice dynamics of wurtzite and rocksalt AlN under high pressure: Effect of compression on the crystal anisotropy of wurtzite-type semiconductors. Physical Review B, 77(20). doi:10.1103/physrevb.77.205204Jephcoat, A. P., Hemley, R. J., Mao, H. K., Cohen, R. E., & Mehl, M. J. (1988). Raman spectroscopy and theoretical modeling of BeO at high pressure. Physical Review B, 37(9), 4727-4734. doi:10.1103/physrevb.37.4727Ibáñez, J., Segura, A., Manjón, F. J., Artús, L., Yamaguchi, T., & Nanishi, Y. (2010). Electronic structure of wurtzite and rocksalt InN investigated by optical absorption under hydrostatic pressure. Applied Physics Letters, 96(20), 201903. doi:10.1063/1.3431291Goñi, A. R., Siegle, H., Syassen, K., Thomsen, C., & Wagner, J.-M. (2001). Effect of pressure on optical phonon modes and transverse effective charges inGaNandAlN. Physical Review B, 64(3). doi:10.1103/physrevb.64.03520

Emulación del sistema músculo-esqueletal y el control de movimiento en una plataforma experimental

Muchos fisiólogos han observado que el músculo humano o animal es una especie de tejido elástico (como un muelle) con componentes contráctiles, los cuales dan una longitud de umbral modificable neuralmente para el desarrollo de fuerzas. La determinación de las fuerzas del músculo durante el movimiento no es solamente esencial para el análisis de las cargas internas que actúan en los huesos y articulaciones, si no que también contribuyen ha entender más profundamente los controladores neuronales. Los sistemas de control biológicos han sido estudiados como una posible inspiración para la construción de controladores de sistemas robóticos. En este trabajo, se diseño e implemento un sistema biomecánico que tiene propiedades mécanicas casi similares a las de un brazo humano o animal. En este sistema se implementaron modelos matemáticos del músculo biológico, para la generación de fuerzas en el músculo esqueletal total. Además, se desarrollo una red cortical para el control de movimientos voluntarios con restricciones neurofisiológicas y psicofísicas motoras. El controlador neuronal es propuesto para realizar el seguimiento de trajectorias deseadas en la articulación de un simple eslabón controlado por un par de actuadores agonista-antagonista con propiedades musculares. El sistema es capaz de ejecutar movimientos de alcance voluntarios, con perfiles de velocidad en forma de campana bajo perturbaciones. Los resultados experimentales muestran que el sistema presenta las propiedades básicas del músculoesqueletal las cuales son las relaciones fuerza-longitud y fuerza-velocidad. El controlador neuronal permite controlar los movimientos deseados y compesar las fuerzas externas.Se agradece el apoyo recibido por los miembros del grupo de investigación de Neurotecnología, Control y Robótica (NEUROCOR) del departamento de Ingeniería de Sistemas y Automática de la Universidad Politécnica de Cartagena. Este trabajo fue financiado en parte por la CICYTTIC99- 0446-C02-01, y por el proyecto SYNERAGH - BRE2-CT980797 BRITE EURAM- de Investigación Básica

Structural and vibrational study of cubic Sb2O3 under high pressure

We report an experimental and theoretical study of antimony oxide (Sb 2O 3) in its cubic phase (senarmontite) under high pressure. X-ray diffraction and Raman scattering measurements up to 18 and 25 GPa, respectively, have been complemented with ab initio total-energy and lattice-dynamics calculations. X-ray diffraction measurements do not provide evidence of a space-group symmetry change in senarmontite up to 18 GPa. However, Raman scattering measurements evidence changes in the pressure coefficients of the Raman mode frequencies at 3.5 and 10 GPa, respectively. The behavior of the Raman modes with increasing pressure up to 25 GPa is fully reproduced by the lattice-dynamics calculations in cubic Sb 2O 3. Therefore, the combined analysis of both experiments and lattice-dynamics calculations suggest the occurrence of two isostructural phase transformations at 3.5 and 10 GPa, respectively. Total-energy calculations show that the isostructural phase transformations occur through local atomic displacements in which senarmontite loses its molecular character to become a three-dimensional solid. In addition, our calculations provide evidence that cubic senarmontite cannot undergo a phase transition to orthorhombic valentinite at high pressure, and that a phase transition to a ß-Bi 2O 3-type structure is possible above 25 GPa. © 2012 American Physical Society.Financial support from the Spanish Consolider Ingenio 2010 Program (Project No. CDS2007-00045) is acknowledged. The work was also supported by Spanish MICCIN under Projects No. CTQ2009-14596-C02-01 and No. MAT2010-21270-C04-01/04 as well as from Comunidad de Madrid and European Social Fund, S2009/PPQ-1551 4161893 (QUIMAPRES) and from Vicerrectorado de Investigacion de la Universitat Politecnica de Valencia under projects UPV2011-0914 PAID-05-11 and UPV2011-0966 PAID-06-11. Spanish Fundacio Bancaixa Project No. P1-1A2009-08 and Brazilian Capes/Fundacion Carolina (BEX 3939/10-3) are also acknowledged.Pereira, ALJ.; Gracia, L.; Santamaría-Pérez, D.; Vilaplana Cerda, RI.; Manjón Herrera, FJ.; Errandonea, D.; Nalin, M.... (2012). Structural and vibrational study of cubic Sb2O3 under high pressure. Physical Review B. 85(17):174108-1-174108-11. https://doi.org/10.1103/PhysRevB.85.174108S174108-1174108-118517Youk, J. H., Kambour, R. P., & MacKnight, W. J. (2000). Polymerization of Ethylene Terephthalate Cyclic Oligomers with Antimony Trioxide†. Macromolecules, 33(10), 3594-3599. doi:10.1021/ma991838dZabinski, J. S., Donley, M. S., & McDevitt, N. T. (1993). Mechanistic study of the synergism between Sb2O3 and MoS2 lubricant systems using Raman spectroscopy. Wear, 165(1), 103-108. doi:10.1016/0043-1648(93)90378-yGhosh, A., & Chakravorty, D. (1991). Transport properties of semiconducting CuO-Sb2O3-P2O5glasses. Journal of Physics: Condensed Matter, 3(19), 3335-3342. doi:10.1088/0953-8984/3/19/012Gopalakrishnan, P. S., & Manohar, H. (1975). Kinetics and mechanism of the transformation in antimony trioxide from orthorhombic valentinite to cubic senarmontite. Journal of Solid State Chemistry, 15(1), 61-67. doi:10.1016/0022-4596(75)90271-6Zachariasen, W. H. (1932). THE ATOMIC ARRANGEMENT IN GLASS. Journal of the American Chemical Society, 54(10), 3841-3851. doi:10.1021/ja01349a006Matsumoto, A., Koyama, Y., Togo, A., Choi, M., & Tanaka, I. (2011). Electronic structures of dynamically stable As2O3, Sb2O3, and Bi2O3crystal polymorphs. Physical Review B, 83(21). doi:10.1103/physrevb.83.214110Miller, P. J., & Cody, C. A. (1982). Infrared and Raman investigation of vitreous antimony trioxide. Spectrochimica Acta Part A: Molecular Spectroscopy, 38(5), 555-559. doi:10.1016/0584-8539(82)80146-3Svensson, C. (1975). Refinement of the crystal structure of cubic antimony trioxide, Sb2O3. Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry, 31(8), 2016-2018. doi:10.1107/s0567740875006759Wood, C., van Pelt, B., & Dwight, A. (1972). The Optical Properties of Amorphous and Crystalline Sb2O3. Physica Status Solidi (b), 54(2), 701-706. doi:10.1002/pssb.2220540234Nalin, M., Messaddeq, Y., Ribeiro, S. J. L., Poulain, M., Briois, V., Brunklaus, G., … Eckert, H. (2004). Structural organization and thermal properties of the Sb2O3–SbPO4glass system. J. Mater. Chem., 14(23), 3398-3405. doi:10.1039/b406075jOrosel, D., Dinnebier, R. E., Blatov, V. A., & Jansen, M. (2012). Structure of a new high-pressure–high-temperature modification of antimony(III) oxide, γ-Sb2O3, from high-resolution synchrotron powder diffraction data. Acta Crystallographica Section B Structural Science, 68(1), 1-7. doi:10.1107/s0108768111046751Grzechnik, A. (1999). Compressibility and Vibrational Modes in Solid As4O6. Journal of Solid State Chemistry, 144(2), 416-422. doi:10.1006/jssc.1999.8189Soignard, E., Amin, S. A., Mei, Q., Benmore, C. J., & Yarger, J. L. (2008). High-pressure behavior ofAs2O3: Amorphous-amorphous and crystalline-amorphous transitions. Physical Review B, 77(14). doi:10.1103/physrevb.77.144113Chouinard, C., & Desgreniers, S. (1999). Bi2O3 under hydrostatic pressure: observation of a pressure-induced amorphization. Solid State Communications, 113(3), 125-129. doi:10.1016/s0038-1098(99)00463-9Geng, A., Cao, L., Wan, C., & Ma, Y. (2011). High-pressure Raman investigation of the semiconductor antimony oxide. physica status solidi (c), 8(5), 1708-1711. doi:10.1002/pssc.201000786Manjón, F. J., & Errandonea, D. (2009). Pressure-induced structural phase transitions in materials and earth sciences. physica status solidi (b), 246(1), 9-31. doi:10.1002/pssb.200844238Mao, H. K., Xu, J., & Bell, P. M. (1986). Calibration of the ruby pressure gauge to 800 kbar under quasi-hydrostatic conditions. Journal of Geophysical Research, 91(B5), 4673. doi:10.1029/jb091ib05p04673Rodríguez-Carvajal, J. (1993). Recent advances in magnetic structure determination by neutron powder diffraction. Physica B: Condensed Matter, 192(1-2), 55-69. doi:10.1016/0921-4526(93)90108-iErrandonea, D., Santamaria-Perez, D., Bondarenko, T., & Khyzhun, O. (2010). New high-pressure phase of HfTiO4 and ZrTiO4 ceramics. Materials Research Bulletin, 45(11), 1732-1735. doi:10.1016/j.materresbull.2010.06.061Errandonea, D., Santamaria-Perez, D., Achary, S. N., Tyagi, A. K., Gall, P., & Gougeon, P. (2011). High-pressure x-ray diffraction study of CdMoO4 and EuMoO4. Journal of Applied Physics, 109(4), 043510-043510-5. doi:10.1063/1.3553850Stroppa, D. G., Montoro, L. A., Beltrán, A., Conti, T. G., da Silva, R. O., Andrés, J., … Ramirez, A. J. (2009). Unveiling the Chemical and Morphological Features of Sb−SnO2Nanocrystals by the Combined Use of High-Resolution Transmission Electron Microscopy and ab Initio Surface Energy Calculations. Journal of the American Chemical Society, 131(40), 14544-14548. doi:10.1021/ja905896uBecke, A. D. (1993). Density‐functional thermochemistry. III. The role of exact exchange. The Journal of Chemical Physics, 98(7), 5648-5652. doi:10.1063/1.464913Lee, C., Yang, W., & Parr, R. G. (1988). Development of the Colle-Salvetti correlation-energy formula into a functional of the electron density. Physical Review B, 37(2), 785-789. doi:10.1103/physrevb.37.785Beltrán, A., Gracia, L., & Andrés, J. (2006). Density Functional Theory Study of the Brookite Surfaces and Phase Transitions between Natural Titania Polymorphs. The Journal of Physical Chemistry B, 110(46), 23417-23423. doi:10.1021/jp0643000Grimme, S. (2006). Semiempirical GGA-type density functional constructed with a long-range dispersion correction. 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Philosophical Magazine, 89(22-24), 1793-1799. doi:10.1080/14786430902917632Akahama, Y., Kobayashi, M., & Kawamura, H. (1991). High-Pressure X-Ray Diffraction Study on Electronics-dTransition in Zirconium. Journal of the Physical Society of Japan, 60(10), 3211-3214. doi:10.1143/jpsj.60.3211Occelli, F., Farber, D. L., Badro, J., Aracne, C. M., Teter, D. M., Hanfland, M., … Couzinet, B. (2004). Experimental Evidence for a High-Pressure Isostructural Phase Transition in Osmium. Physical Review Letters, 93(9). doi:10.1103/physrevlett.93.095502Zarechnaya, E., Dubrovinskaia, N., Caracas, R., Merlini, M., Hanfland, M., Filinchuk, Y., … Dubrovinsky, L. (2010). Pressure-induced isostructural phase transformation inγ-B28. Physical Review B, 82(18). doi:10.1103/physrevb.82.184111Chatterjee, A., Singh, A. K., & Jayaraman, A. (1972). Pressure-Induced Electronic Collapse and Structural Changes in Rare-Earth Monochalcogenides. Physical Review B, 6(6), 2285-2291. doi:10.1103/physrevb.6.2285Chefki, M., Abd-Elmeguid, M. M., Micklitz, H., Huhnt, C., Schlabitz, W., Reehuis, M., & Jeitschko, W. (1998). Pressure-induced Transition of the Sublattice Magnetization inEuCo2P2: Change from Local MomentEu(4f)to ItinerantCo(3d)Magnetism. Physical Review Letters, 80(4), 802-805. doi:10.1103/physrevlett.80.802Caracas, R., & Gonze, X. (2004). Structural, electronic, and dynamical properties of calaveriteAuTe2under pressure. Physical Review B, 69(14). doi:10.1103/physrevb.69.144114Svane, A., Strange, P., Temmerman, W. M., Szotek, Z., Winter, H., & Petit, L. (2001). Pressure-Induced Valence Transitions in Rare Earth Chalcogenides and Pnictides. physica status solidi (b), 223(1), 105-116. doi:10.1002/1521-3951(200101)223:13.0.co;2-iYoo, C. S., Maddox, B., Klepeis, J.-H. P., Iota, V., Evans, W., McMahan, A., … Pickett, W. E. (2005). First-Order Isostructural Mott Transition in Highly Compressed MnO. Physical Review Letters, 94(11). doi:10.1103/physrevlett.94.115502Rosner, H., Koudela, D., Schwarz, U., Handstein, A., Hanfland, M., Opahle, I., … Richter, M. (2006). Magneto-elastic lattice collapse in YCo5. Nature Physics, 2(7), 469-472. doi:10.1038/nphys341Polian, A., Gauthier, M., Souza, S. M., Trichês, D. M., Cardoso de Lima, J., & Grandi, T. A. (2011). Two-dimensional pressure-induced electronic topological transition in Bi2Te3. Physical Review B, 83(11). doi:10.1103/physrevb.83.113106Vilaplana, R., Gomis, O., Manjón, F. J., Segura, A., Pérez-González, E., Rodríguez-Hernández, P., … Kucek, V. (2011). High-pressure vibrational and optical study of Bi2Te3. Physical Review B, 84(10). doi:10.1103/physrevb.84.104112Vilaplana, R., Santamaría-Pérez, D., Gomis, O., Manjón, F. J., González, J., Segura, A., … Kucek, V. (2011). Structural and vibrational study of Bi2Se3under high pressure. 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A theoretical study of the Pnma and R3m phases of Sb2S3, Bi2S3, and Sb2Se3

[EN] We report a comparative theoretical study of the Pnma and R3m phases of Sb2S3, Bi2S3, and Sb2Se3 close to ambient pressure. Our enthalpy calculations at 0 K show that at ambient pressure the R3m (tetradymite-like) phase of Sb2Se3 is energetically more stable than the Pnma phase, contrary to what is observed for Sb2S3 and Bi2S3, and irrespective of the exchange-correlation functional employed in the calculations. The result for Sb2Se3 is in contradiction to experiments in which all three compounds are usually grown in the Pnma phase. This result is further confirmed by free-energy calculations taking into account the temperature dependence of unit-cell volumes and phonon frequencies. Lattice dynamics and elastic tensor calculations further show that both the Pnma and R3m phases of Sb2Se3 are dynamically and mechanically stable at zero applied pressure. Since these results suggest that the formation of the R3m phase of Sb2Se3 should be feasible under close to ambient conditions, we provide a theoretical crystal structure and simulated Raman and infrared spectra to help in its identification. We also discuss the results of the two published works that have claimed to have synthesized tetradymite-like Sb2Se3. Finally, the stability of the R3m phase across the three group-15 A(2)X(3) sesquichalcogenides is analysed based on their van der Waals gap and X-X in-plane geometry.This publication is part of the MALTA Consolider Team network (RED2018-102612-T) (MINECO/AEI/10.13039/501100003329), and is supported by I + D + i project PID2019-106383GB41/42/43 (MCIN/AEI/10.13039/501100011033), by the PROMETEO/2018/123(EFIMAT) and CIPROM/2021/075 (GREENMAT) projects (Generalitat Valenciana), and by the European Union Horizon 2020 research and innovation programme under a Marie Sklodowska-Curie grant agreement (785789-COMEX). E. L. d. S., A. M., and P. R.-H. acknowledge computing time provided on the MALTA-Cluster at the University of Oviedo and on the MareNostrum facility through Red Espanola de Supercomputacion (RES) with technical support provided by the Barcelona Supercomputing Center (QCM-2018-3-0032). E. L. d. S. also acknowledges the Network of Extreme Conditions Laboratories (NECL), financed by FCT and co-financed by NORTE 2020 through the Portugal 2020 and FEDER programmes. J. M. S. is grateful to UK Research and Innovation for the support of a Future Leaders Fellowship (MR/T043121/1) and to the University of Manchester for the previous support of a Presidential Fellowship.Da Silva, EL.; Skelton, JM.; Rodríguez-Hernández, P.; Muñoz, A.; Santos, MC.; Martínez-García, D.; Vilaplana Cerda, RI.... (2022). A theoretical study of the Pnma and R3m phases of Sb2S3, Bi2S3, and Sb2Se3. Journal of Materials Chemistry C. 10(40):15061-15074. https://doi.org/10.1039/d2tc01484j1506115074104

Rúbrica para la evaluación de la habilidad de determinar la presión arterial

Podeu consultar la Vuitena trobada de professorat de Ciències de la Salut completa a: http://hdl.handle.net/2445/66524La determinación de la presión arterial (Pa) forma parte de la atención farmacéutica tanto desde el punto de vista del cribado de la hipertensión en la población general como en el seguimiento del enfermo hipertenso1. Por ello, la habilidad de determinar la Pa constituye uno de los objetivos de aprendizaje del grado de Farmacia de la Universitat de Barcelona y se desarrolla en las clases prácticas de la asignatura de Fisiología y Fisiopatología II. En cada curso académico, la práctica se enseña durante 2 horas a unos 350 alumnos repartidos en 17-18 grupos de docencia. Días después de realizar la práctica, el profesor evalúa el grado de adquisición de dicha habilidad por parte del estudiante, el cual realiza la medición de Pa a un compañero. Si bien el guión de prácticas recoge las fases a seguir para la determinación correcta de la Pa y que son objeto de evaluación, el profesorado implicado en la evaluación otorgaba una puntuación global a la habilidad..