249 research outputs found

    Evaluación de impacto ambiental de Galicia

    Get PDF
    Este libro recolle as sesións correspondentes o módulo avaliación do impacto ambiental do Master de Ciencia e Tecnoloxía Ambiental, dirixido polo profesor D. Xosé Luis Armesto Barbeito que se desenvolbe desde 1992 na Facultarle de Ciencia

    Insights onto the magnetic coupling at hexaferrite-based hard/soft bilayer systems

    Get PDF
    IBERTRIVA 2019 X Iberian Conference on Tribology – IBERTRIB, XI Iberian Vacuum Conference - RIVA, Seville, Spain,June 26-28Magnets are used in a variety of applications, such as generators, magnetic recording media, components in RF and microwave devices. However, many of these magnets contain s rare earths, critical elements whose extraction is environmentally harmful and that present price volatility risks. Their replacement by cheaper and more environmentally friendly materials is therefore sought. In our case, we have focused on magnetically hard strontium hexaferrite (SrFe 12O19, SFO) as the base for alternative permanent magnets (Figure 1a). The atomic arrangement of this ferrite results in a high magnetocrystalline anisotropy and a coercive field, however, its magnetization is moderate (1). It is well known that the coupling between a magnetically hard and soft material improved magnetization while avoiding a high cost in coercitivity loss (2). However, results have been disappointing so far as structural and geometrical limitations make it extremely challenging to fabricate. In this work, we aim at further understanding the magnetic coupling at hard -soft interfaces involving ferrites, for which we have deposited soft iron and cobalt metals on top of SrFe12O19 thin films with controlled easy-axis of magnetization. SFO thin films have been obtained by RF magnetron sputtering at 260W followed by a subsequent annealing in air of 850ºC. Their structure and composition was characterized by Raman spectroscospy (Figure 1b), Mössbauer spectroscopy, X-ray photoemission spectroscopy and low-energy electron microscopy (LEEM). We have grown the magnetically soft layer by molecular-beam epitaxy and we have analyzed the resulting bilayer system through photoemission electron microscopy, LEEM and vibrating-sample magnetometry. References [1] R.C. Pullar, Hexagonal ferrites: a review of the synthesis, properties and applications of hexaferrite ceramics, Progress in Materials Science 57 (2012), pp 1191¿1334. [2] Eric E. Fullerton, J. S. Jiang, M. Grimsditch, C. H. Sowers, and S. D. Bader, Exchange-spring behavior in epitaxial hard/soft magnetic bilayers, Phys. Rev. B 58 (1998) 1219

    Diseño y posicionado de la prótesis inversa de hombro utilizando técnicas de simulación numérica por método de los elementos ¿nitos y biomodelos realizados por impresión 3D

    Get PDF
    Analizar el posicionado y orientación de la prótesis inversa de hombro (PIH) en la escápula, y mejorar su anclaje y adaptación utilizando técnicas de Simulación Numérica por metodología de elementos finitos (FEM) y biomodelos realizados por impresión 3D. Métodos. Mediante la TAC de un paciente intervenido de PIH se genera un biomodelo 3D-virtual. Se estudia el conjunto placa base-escápula mediante software FEM simulando el comportamiento mecánico, comparando la intervención frente a unas condiciones de excentricidad de 4 mm y lateralización de 5mm. Se analizan las tensiones y deformaciones ejercidas. Resultados. Se obtiene una reducción de los esfuerzos mecánicos en la placa base de 23,7%. Se diseña un dispositivo de centrado-guía, elaborado mediante la técnica de impresión 3D. Conclusión. El modelado y análisis FEM de la morfología del hombro del paciente y su biomodelo 3D ayudan a una óptima planificación pre-operatoria. La impresión de guías 3D puede mejorar el posicionamiento y anclaje de la placa base de la PI

    Diseño y posicionado de la prótesis inversa de hombro utilizando técnicas de simulación numérica por método de los elementos finitos y biomodelos realizados por impresión 3D

    Full text link
    [EN] Purpose. To analyze the positioning and orientation of a reverse shoulder prostheses in the scapula, and to improve its anchorage and adaptation using numerical simulation techniques trough finite element methodology (FEM) and biomodels by 3D printing. Methods. A 3D-virtual biomodel is generated by the CT of a male patient of 70 kg and load in a 4,2 kg arm, operated with RSA. The base plate-scapula is studied by FEM software simulating the mechanical behavior, comparing the intervention against eccentricity conditions of 4 mm and lateralization of 5 mm. The tensions and deformations performed on the interface are analyzed. Results. A reduction of the mechanical stress in the base plate of 23.7% is obtained. A guide-centering device, designed using the 3D printing modeling technique, is designed. Conclusion. The FEM modeling and analysis of the patient¿s personalized shoulder morphology and 3D biomodel help optimum preoperative planning. Printing 3D guides can improve the positioning and anchoring of the RSA base plate.[ES] Objetivo. Analizar el posicionado y orientación de la prótesis inversa de hombro (PIH) en la escápula, y mejorar su anclaje y adaptación utilizando técnicas de Simulación Numérica por metodología de elementos finitos (FEM) y biomodelos realizados por impresión 3D. Métodos. Mediante la TAC de un paciente intervenido de PIH se genera un biomodelo 3D-virtual. Se estudia el conjunto placa base-escápula mediante software FEM simulando el comportamiento mecánico, comparando la intervención frente a unas condiciones de excentricidad de 4 mm y lateralización de 5mm. Se analizan las tensiones y deformaciones ejercidas. Resultados. Se obtiene una reducción de los esfuerzos mecánicos en la placa base de 23,7%. Se diseña un dispositivo de centrado-guía, elaborado mediante la técnica de impresión 3D. Conclusión. El modelado y análisis FEM de la morfología del hombro del paciente y su biomodelo 3D ayudan a una óptima planificación pre-operatoria. La impresión de guías 3D puede mejorar el posicionamiento y anclaje de la placa base de la PIH.Salvador Marín, J.; Piles-Cabo, L.; Seguí, JM.; Sanchez-Caballero, S.; Reig-Pérez, MJ.; Pla-Ferrando, R.; Ferrándiz Bou, S.... (2017). Diseño y posicionado de la prótesis inversa de hombro utilizando técnicas de simulación numérica por método de los elementos finitos y biomodelos realizados por impresión 3D. Revista Española de Cirugía Osteoarticular. 52(271):96-101. http://hdl.handle.net/10251/148361S961015227

    The Spanish Infrared Camera onboard the EUSO-BALLOON (CNES) flight on August 24, 2014

    Get PDF
    The EUSO-Balloon (CNES) campaign was held during Summer 2014 with a launch on August 24. In the gondola, next to the Photo Detector Module (PDM), a completely isolated Infrared camera was allocated. Also, a helicopter which shooted flashers flew below the balloon. We have retrieved the Cloud Top Height (CTH) with the IR camera, and also the optical depth of the nonclear atmosphere have been inferred with two approaches: The first one is with the comparison of the brightness temperature of the cloud and the real temperature obtained after the pertinent corrections. The second one is by measuring the detected signal from the helicopter flashers by the IR Camera, considering the energy of the flashers and the location of the helicopter

    Permanent Genetic Resources added to Molecular Ecology Resources Database 1 February 2013-31 March 2013

    Get PDF
    This article documents the addition of 142 microsatellite marker loci to the Molecular Ecology Resources database. Loci were developed for the following species: Agriophyllum squarrosum, Amazilia cyanocephala, Batillaria attramentaria, Fungal strain CTeY1 (Ascomycota), Gadopsis marmoratus, Juniperus phoenicea subsp. turbinata, Liriomyza sativae, Lupinus polyphyllus, Metschnikowia reukaufii, Puccinia striiformis and Xylocopa grisescens. These loci were cross-tested on the following species: Amazilia beryllina, Amazilia candida, Amazilia rutila, Amazilia tzacatl, Amazilia violiceps, Amazilia yucatanensis, Campylopterus curvipennis, Cynanthus sordidus, Hylocharis leucotis, Juniperus brevifolia, Juniperus cedrus, Juniperus osteosperma, Juniperus oxycedrus, Juniperus thurifera, Liriomyza bryoniae, Liriomyza chinensis, Liriomyza huidobrensis and Liriomyza trifolii. © 2013 John Wiley & Sons Ltd.Peer Reviewe

    Non-invasive ventilation in obesity hypoventilation syndrome without severe obstructive sleep apnoea

    Get PDF
    Background Non-invasive ventilation (NIV) is an effective form of treatment in patients with obesity hypoventilation syndrome (OHS) who have concomitant severe obstructive sleep apnoea (OSA). However, there is a paucity of evidence on the efficacy of NIV in patients with OHS without severe OSA. We performed a multicentre randomised clinical trial to determine the comparative efficacy of NIV versus lifestyle modification (control group) using daytime arterial carbon dioxide tension (PaCO2) as the main outcome measure. Methods Between May 2009 and December 2014 we sequentially screened patients with OHS without severe OSA. Participants were randomised to NIV versus lifestyle modification and were followed for 2 months. Arterial blood gas parameters, clinical symptoms, health-related quality of life assessments, polysomnography, spirometry, 6-min walk distance test, blood pressure measurements and healthcare resource utilisation were evaluated. Statistical analysis was performed using intention-to-treat analysis. Results A total of 365 patients were screened of whom 58 were excluded. Severe OSA was present in 221 and the remaining 86 patients without severe OSA were randomised. NIV led to a significantly larger improvement in PaCO2 of -6 (95% CI -7.7 to -4.2) mm Hg versus -2.8 (95% CI -4.3 to -1.3) mm Hg, (p<0.001) and serum bicarbonate of -3.4 (95% CI -4.5 to -2.3) versus -1 (95% CI -1.7 to -0.2 95% CI) mmol/L (p<0.001). PaCO2 change adjusted for NIV compliance did not further improve the inter-group statistical significance. Sleepiness, some health-related quality of life assessments and polysomnographic parameters improved significantly more with NIV than with lifestyle modification. Additionally, there was a tendency towards lower healthcare resource utilisation in the NIV group. Conclusions NIV is more effective than lifestyle modification in improving daytime PaCO2, sleepiness and polysomnographic parameters. Long-term prospective studies are necessary to determine whether NIV reduces healthcare resource utilisation, cardiovascular events and mortality

    The atmospheric science of JEM-EUSO

    Get PDF
    An Atmospheric Monitoring System (AMS) is critical suite of instruments for JEM-EUSO whose aim is to detect Ultra-High Energy Cosmic Rays (UHECR) and (EHECR) from Space. The AMS comprises an advanced space qualified infrared camera and a LIDAR with cross checks provided by a ground-based and airborne Global Light System Stations. Moreover the Slow Data Mode of JEM-EUSO has been proven crucial for the UV background analysis by comparing the UV and IR images. It will also contribute to the investigation of atmospheric effects seen in the data from the GLS or even to our understanding of Space Weather
    corecore