33 research outputs found

    Multilayer and particle size-graded YSZ coatings obtained by plasma spraying of micro- and nanostructured feedstocks

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    This work was supported by the Spanish Ministry of Science and Innovation (Project MAT2012-38364-C03) and the Research Promotion Plan of Universitat Jaume I, action 3.1 (Ref. PREDOC/2009/10), and it has been co-funded by the European Regional Development Fund (ERDF). The authors also thank the SCIC of Universitat Jaume I for the FEG-SEM observationsCarpio, P.; Bannier, E.; Salvador Moya, MD.; Benavente Martínez, R.; Sanchez Vilches, E. (2014). Multilayer and particle size-graded YSZ coatings obtained by plasma spraying of micro- and nanostructured feedstocks. Journal of Thermal Spray Technology. 23(8):1362-1372. https://doi.org/10.1007/s11666-014-0143-9S13621372238D.R. Clarke and S.R. Phillpot, Thermal Barrier Coatings Materials, Mater. Today, 2005, 8, p 22-29N.P. Patdure, M. Gell, and E.H. Jordan, Thermal Barrier Coatings for Gas-Turbine Engine Applications, Science, 2002, 296, p 280-284L. Pawlowski, Finely Grained Nanometric and Submicrometric Coatings by Thermal Spraying: A Review, Surf. Coat. Technol., 2008, 205(43), p 18-28R.S. Lima and B.R. Marple, Thermal Spray Coatings Engineered from Nanostructured Ceramic Agglomerated Powders for Structural, Thermal Barrier and Biomedical Applications: A Review, J. Therm. Spray Technol., 2007, 16(1), p 40-63P. Fauchais, G. Montavon, R.S. Lima, and B.R. Marple, Engineering a New Class of Thermal Spray Nano-Based Microstructures from Agglomerated Nanostructured Particles, Suspensions and Solutions: An Invited Review, J. Phys. D, 2011, 44(9), 93001, p 1-131M. Gell, E.H. Jordan, Y.H. Sohn, D. Goberman, L. Shaw, and T.D. Xiao, Development and Implementation of Plasma Sprayed Nanostructured Ceramic Coatings, Surf. Coat. Technol., 2001, 146-147, p 48-54R.S. Lima and B.R. Marple, Nanostructured YSZ Thermal Barrier Coatings Engineered to Counteract Sintering Effects, Mater. Sci. Eng. A, 2008, 485, p 182-193H. Chen, X. Zhou, and C. Ding, Investigation of the Thermomechanical Properties of a Plasma-Sprayed Nanostructured Zirconia Coating, J. Eur. Ceram. Soc., 2003, 23, p 1449-1455K.A. Khor and Y.W. Gu, Thermal Properties of Plasma-Sprayed Graded Thermal Barrier Coatings, Thin Solid Films, 2000, 372, p 104-113A.M. Limarga, T.S. Widjajab, and T.H. Yip, Mechanical Properties and Oxidation Resistance of Plasma-Sprayed Multilayered Al2O3/ZrO2 Thermal Barrier Coatings, Surf. Coat. Technol., 2005, 197, p 93-102X. Chen, Y. Zhao, X. Fan, Y. Liu, B. Zou, Y. Wang, H. Ma, and X. Cao, Thermal Cycling Failure of New LaMgAl11O19/YSZ Double Ceramic Top Coat Thermal Barrier Coating Systems, Surf. Coat. Technol., 2011, 205, p 3293-3300G. Mauer, M.O. Jarligo, D.E. Mack, and R. Vassen, Plasma-Sprayed Thermal Barrier Coatings: New Materials, Processing Issues and Solutions, J. Therm. Spray Technol., 2013, 22(5), p 647-658A. Portinha, V. Teixeira, J. Carneiro, J. Martins, M.F. Costa, R. Vassen, and D. Stoever, Characterization of Thermal Barrier Coatings with a Gradient in Porosity, Surf. Coat. Technol., 2005, 195, p 245-251M. Vicent, E. Sánchez, G. Mallol, and R. Moreno, Study of Colloidal Behaviour and Rheology of Al2O3-TiO2 Nanosuspensions to Obtain Free-Flowing Spray-Dried Granules for Atmospheric Plasma Spraying, Ceram. Int., 2013, 39(7), p 8103-8111F. Müller, W. Peukert, R. Polke, and R. Stenger, Dispersing Nanoparticles in Liquids, Int. J. Miner. Process., 2000, 74, p S31-S34M. Vicent, E. Bannier, R. Moreno, M.D. Salvador, and E. Sánchez, Atmospheric Plasma Spraying Coatings from Alumina-Titania Feedstock Comprising Bimodal Particle Size Distributions, J. Eur. Ceram. Soc., 2013, 33, p 3313-3324C.W. Kang and H.W. Ng, Splat Morphology and Spreading Behaviour due to Oblique Impact of Droplets onto Substrates in Plasma Spray Coating Process, Surf. Coat. Technol., 2006, 200, p 5462-5477Y. Zeng, S.W. Lee, L. Gao, and C.X. Ding, Atmospheric Plasma Sprayed Coatings of Nanostructured Zirconia, J. Eur. Ceram. Soc., 2002, 22, p 347-351R.S. Lima, A. Kucuk, and C.C. Berndt, Integrity of Nanostructured Partially Stabilized Zirconia After Plasma Spray Processing, Mater. Sci. Eng. A, 2001, 13, p 75-82L. Wang, Y. Wang, X.G. Sun, J.Q. He, Z.Y. Pan, and C.H. Wang, Microstructure and Indentation Mechanical Properties of Plasma Sprayed Nano-bimodal and Conventional ZrO2-8 wt%Y2O3 Thermal Barrier Coatings, Vacuum, 2012, 86(8), p 1174-1185L.L. Shaw, D. Goberman, R. Ren, M. Gell, S. Jiang, Y. Wang, T.D. Xiao, and P.R. Strutt, The Dependency of Microstructure and Properties of Nanostructured Coatings on Plasma Spray Conditions, Surf. Coat. Technol., 2000, 130(1), p 1-8R.S. Lima, A. Kucuk, and C.C. Berndt, Bimodal Distribution of Mechanical Properties on Plasma Sprayed Nanostructured Partially Stabilized Zirconia, J. Mater. Sci. Eng. A, 2002, 327, p 224-232T. Wakui, J. Malzbender, and R.W. Steinbrech, Strain Dependent Stiffness of Plasma Sprayed Thermal Barrier Coatings, Surf. Coat. Technol., 2006, 200(16-17), p 4995-5002J. Malzbender and R.W. Steinbrech, Determination of the Stress-Dependent Stiffness of Plasma-Sprayed Thermal Barrier Coatings Using Depth-Sensitive Indentation, J. Mater. Res., 2003, 18(8), p 1975-198

    Impact of Feedstock Nature on Thermal Conductivity of YSZ Thermal Barrier Coatings Obtained by Plasma Spraying

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    [EN] Yttria-stabilized zirconia (YSZ) coatings with low thermal conductivity were obtained using three different particle size distributions as starting powder: nano-, submicron- and bimodal submicron/nano-sized particles. On the one hand, these particles were reconstituted into micrometric, spray-dry agglomerates, which were subsequently deposited by means of conventional atmospheric plasma spraying (APS). On the other hand, the starting particles were dispersed in water and the resultant suspensions were deposited by means of suspension plasma spraying (SPS). The coatings were thermally treated to assess their sintering resistance. As-sprayed and thermally treated coatings were then characterized in terms of microstructure (FEG-SEM) and thermal diffusivity (laser flash equipment). The results showed that SPS coatings exhibited extremely low thermal conductivity at low temperature which drastically augmented with increasing temperature. On the other hand, APS coatings also exhibited low thermal conductivities but their values were higher than those of the SPS coatings at the lowest temperature tested while the conductivities hardly varied with temperature.This work has been supported by the Spanish Ministry of Economy and Competitiveness (project MAT2015-67586-C3-R) and Research Promotion Plan of the Universitat Jaume I, action 2.1 (ref. E-2011 - 05) and action 3.1 (ref. PREDOC/2009/10). A. Borrell acknowledges the Spanish Ministry of Economy and Competitiveness for her Juan de la Cierva-Incorporacion contract (IJCI-2014-19839). M. Miranda would like to thank the European Commission (FP7-Marie Curie Intra-European Fellowship, BIOHYMAT).Carpio-Cobo, P.; Salvador Moya, MD.; Benavente Martínez, R.; Miranda, M.; Borrell Tomás, MA.; Sánchez, E. (2016). Impact of Feedstock Nature on Thermal Conductivity of YSZ Thermal Barrier Coatings Obtained by Plasma Spraying. Journal of Ceramic Science and Technology. 7(3):307-312. https://doi.org/10.4416/JCST2016-00022S3073127

    La protección de los socios externos en los grupos de sociedades en el Anteproyecto de Ley de Código Mercantil

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    El presente artículo se centra en el análisis de algunas cuestiones que suscita el régimen proyectado de los grupos de sociedades en el Anteproyecto de Ley de Código Mercantil de 30 de mayo de 2014. Se estudian las medidas de tutela de los socios externos; en concreto, el deber de información de la pertenencia al grupo, la acción de responsabilidad en defensa del interés social de la sociedad dependiente, el derecho de separación, la indemnización en caso de adquisición por la sociedad dominante de la totalidad del capital social de la sociedad dependiente y, por último, el derecho de información contable. En todos los temas se han tenido en cuenta el Derecho de sociedades vigente, el Derecho proyectado y las aportaciones de la jurisprudencia y la doctrina

    Modification of the properties of Al2O3/TZ-3YS thermal barrier coating by the addition of silicon carbide particles and fructose

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    Al2O3/TZ-3YS coatings developed by suspension plasma spraying were studied in the present work. Mechanical and thermal characterization was realized to evaluate the suitability of thermal barrier coatings. In addition, SiC particle reinforcement was evaluated for its effect on the mechanical properties of the coating. The problem with SiC reinforcement is its high melting point that causes a large amount of unmolten material to be deposited on the coating. One possible solution followed in the present study consists of including fructose as an additive in order to modify the suspension characteristics. The results conclude that the use of fructose as an additive increases the mechanical and thermal properties (from 1.0 to 1.6 W/m·K), since the microstructure is modified, and results in a lower porosity (17%) compared to the SiC coating (25%)

    Microstructure and mechanical properties of plasma spraying coatings from YSZ feedstocks comprising nano- and submicron-sized particles

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    Atmospheric plasma spraying (APS) is an attractive technique to obtain nanostructured coatings due to its versatility, simplicity and relatively low cost. However, nanoparticles cannot be fed into the plasma using conventional feeding systems, due to their low mass and poor flowability, and must be adequately reconstituted into sprayable micrometric agglomerates. In this work, nanostructured and submicron/nanostiuctured powders of yttria-stabilised zirconia (YSZ) were deposited using APS, with a view to obtaining high-performance thermal bather coatings (IBC). All powders were reconstituted by spray-drying from different solid loading suspensions, followed by a thermal treatment of the spray-dried granules to reduce agglomerate porosity and enhance powder sinterability. The reconstituted granules were characterised by XRD, SEM, pore sizing and flowability evaluation. The reconstituted feedstocks were successfully deposited onto metallic substrates by APS. A metallic bond coat was sprayed between the substrate and the ceramic layer. The coating microstructure, characterised by SEM, was formed by partially melted zones, which retained the initial powder microstructure, embedded in a fully melted matrix which acts as a binder. It was shown that feedstock characteristics which in turn are very dependent of starting suspension characteristics, in particular agglomerate density and primary particle size, impact on coating microstructure (porosity and amount of partially-melted areas). For this reason mechanical properties of coatings are also strongly affected by feeding powder characteristics. (C) 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.This work has been supported by the Spanish Ministry of Economy and Competitiveness (project MAT2012-38364-C03), by the Research Promotion Plan of the Universitat Jaume I, action 3.1 (ref. PREDOC/2009/10) and it has been co-funded by ERDF (European Regional Development Funds). The authors also acknowledge the SCIC of Valencia University for the FEG-SEM observations. Finally the Spanish Ministry of Science and Innovation for Juan de la Cierva contract (JCI-2011-10498) is also grateful.Carpio, P.; Borrell Tomás, MA.; Salvador Moya, MD.; Gómez, A.; Martínez, E.; Sánchez, E. (2015). Microstructure and mechanical properties of plasma spraying coatings from YSZ feedstocks comprising nano- and submicron-sized particles. Ceramics International. 41(3, Part A):4108-4117. https://doi.org/10.1016/j.ceramint.2014.11.106S41084117413, Part

    Efectividad del plan de contingencia de la Unidad de Enfermedad Inflamatoria Intestinal ante la infección de Covid-19.

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    Fundamentos: La toma de decisiones en los hospitales y en sus propios servicios asistenciales apenas está referenciada en la literatura. Durante el período de pandemia por Covid-19, los servicios asistenciales han puesto en marcha planes de contingencia para minimizar las consecuencias del coronavirus en los profesionales y pacientes. Sin embargo, apenas se comparte el despliegue de esos planes de contingencia, ni sus resultados, privando de referencias para refutar, comparar o emular los citados planes a otros servicios asistenciales u hospitales. El objetivo del trabajo fue la descripción de la puesta en marcha de dichos planes ante la pandemia de Covid-19 en la Unidad de Enfermedad Inflamatoria Intestinal de un Servicio de Digestivo en el Área Sanitaria de Pontevedra e O Salnés (Galicia). Métodos: Un equipo de directivos y profesionales adaptaron al entorno sanitario las 10 medidas recomendadas por Deloitte para afrontar una pandemia. A continuación, se formularon las medidas como listado de comprobación. A partir del ciclo de mejora Plan-Do-Check-Act, se agruparon las 10 medidas en las siguientes categorías: gestión del riesgo, gestión organizacional y toma de decisiones. Por último, un equipo externo realizó una evaluación cualitativa de la puesta en marcha del plan de contingencia realizado. Resultados: La Unidad de Enfermedad Inflamatoria Intestinal del Servicio de Digestivo realizó un plan de contingencia que presenta un cumplimiento de las 10 medidas recomendadas para hacer frente a la pandemia de Covid-19 con garantías. Conclusiones: Compartir el despliegue del plan de contingencia y sus resultados es útil para identificar buenas prácticas. Este trabajo ofrece un método para evaluar las tomas de decisiones en los plantes de contingencia en situaciones de pandemia. Los resultados sitúan a la Unidad de Enfermedad Inflamatoria Intestinal en el rango de la excelencia

    Cell free circulating tumor DNA in cerebrospinal fluid detects and monitors central nervous system involvement of B-cell lymphomas

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    Limfoma no Hodgkin agressiu; Limfoma del SNCLinfoma no Hodgkin agresivo; Linfoma del SNCAggressive Non-Hodgkin's Lymphoma; CNS lymphomaThe levels of cell free circulating tumor DNA (ctDNA) in plasma correlated with treatment response and outcome in systemic lymphomas. Notably, in brain tumors, the levels of ctDNA in the cerebrospinal fluid (CSF) are higher than in plasma. Nevertheless, their role in central nervous system (CNS) lymphomas remains elusive. We evaluated the CSF and plasma from 19 patients: 6 restricted CNS lymphomas, 1 systemic and CNS lymphoma, and 12 systemic lymphomas. We performed whole exome sequencing or targeted sequencing to identify somatic mutations of the primary tumor, then variant-specific droplet digital PCR was designed for each mutation. At time of enrolment, we found ctDNA in the CSF of all patients with restricted CNS lymphoma but not in patients with systemic lymphoma without CNS involvement. Conversely, plasma ctDNA was detected in only 2/6 patients with restricted CNS lymphoma with lower variant allele frequencies than CSF ctDNA. Moreover, we detected CSF ctDNA in 1 patient with CNS lymphoma in complete remission and in 1 patient with systemic lymphoma, 3 and 8 months before CNS relapse was confirmed; indicating CSF ctDNA might detect CNS relapse earlier than conventional methods. Finally, in 2 cases with CNS lymphoma, CSF ctDNA was still detected after treatment even though a complete decrease in CSF tumor cells was observed by flow cytometry (FC), indicating CSF ctDNA better detected residual disease than FC. In conclusion, CSF ctDNA can better detect CNS lesions than plasma ctDNA and FC. In addition, CSF ctDNA predicted CNS relapse in CNS and systemic lymphomas.This work was supported by research funding from Fundación Asociación Española contra el Cáncer (AECC) (to JS, MC and PA); FERO (to JS), laCaixa (to JS), BBVA (CAIMI) (to JS), the Instituto de Salud Carlos III, Fondo de Investigaciones Sanitarias (PI16/01278 to JS; PI17/00950 to MC; PI17/00943 to FB) cofinanced by the European Regional Development Fund (ERDF) and Gilead Fellowships (GLD16/00144, GLD18/00047, to FB). MC holds a contract from Ministerio de Ciencia, Innovación y Universidades (RYC-2012-12018). SB received funding from Fundación Alfonso Martin Escudero. LE received funding from the Juan de la Cierva fellowship. We thank CERCA Programme / Generalitat de Catalunya for institutional support

    Risk Factors for COVID-19 in Inflammatory Bowel Disease: A National, ENEIDA-Based Case–Control Study (COVID-19-EII)

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    (1) Scant information is available concerning the characteristics that may favour the acquisition of COVID-19 in patients with inflammatory bowel disease (IBD). Therefore, the aim of this study was to assess these differences between infected and noninfected patients with IBD. (2) This nationwide case-control study evaluated patients with inflammatory bowel disease with COVID-19 (cases) and without COVID-19 (controls) during the period March-July 2020 included in the ENEIDA of GETECCU. (3) A total of 496 cases and 964 controls from 73 Spanish centres were included. No differences were found in the basal characteristics between cases and controls. Cases had higher comorbidity Charlson scores (24% vs. 19%; p = 0.02) and occupational risk (28% vs. 10.5%; p < 0.0001) more frequently than did controls. Lockdown was the only protective measure against COVID-19 (50% vs. 70%; p < 0.0001). No differences were found in the use of systemic steroids, immunosuppressants or biologics between cases and controls. Cases were more often treated with 5-aminosalicylates (42% vs. 34%; p = 0.003). Having a moderate Charlson score (OR: 2.7; 95%CI: 1.3-5.9), occupational risk (OR: 2.9; 95%CI: 1.8-4.4) and the use of 5-aminosalicylates (OR: 1.7; 95%CI: 1.2-2.5) were factors for COVID-19. The strict lockdown was the only protective factor (OR: 0.1; 95%CI: 0.09-0.2). (4) Comorbidities and occupational exposure are the most relevant factors for COVID-19 in patients with IBD. The risk of COVID-19 seems not to be increased by immunosuppressants or biologics, with a potential effect of 5-aminosalicylates, which should be investigated further and interpreted with caution

    Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

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    The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

    4to. Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad. Memoria académica

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    Este volumen acoge la memoria académica de la Cuarta edición del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad, CITIS 2017, desarrollado entre el 29 de noviembre y el 1 de diciembre de 2017 y organizado por la Universidad Politécnica Salesiana (UPS) en su sede de Guayaquil. El Congreso ofreció un espacio para la presentación, difusión e intercambio de importantes investigaciones nacionales e internacionales ante la comunidad universitaria que se dio cita en el encuentro. El uso de herramientas tecnológicas para la gestión de los trabajos de investigación como la plataforma Open Conference Systems y la web de presentación del Congreso http://citis.blog.ups.edu.ec/, hicieron de CITIS 2017 un verdadero referente entre los congresos que se desarrollaron en el país. La preocupación de nuestra Universidad, de presentar espacios que ayuden a generar nuevos y mejores cambios en la dimensión humana y social de nuestro entorno, hace que se persiga en cada edición del evento la presentación de trabajos con calidad creciente en cuanto a su producción científica. Quienes estuvimos al frente de la organización, dejamos plasmado en estas memorias académicas el intenso y prolífico trabajo de los días de realización del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad al alcance de todos y todas
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