496 research outputs found

    Effects of isothermal oxidation on the local wear behaviour of laser cladded Inconel 625 coatings

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    Ni-based alloys, such as Inconel superalloys, are characterized by high strength, excellent fabricability (including joining), and outstanding corrosion resistance. However, their use is limited by their high cost. Ni-based coatings are used on carbon steel components in order to increase their service life under extreme conditions. Laser cladding deposition has emerged as an excellent method for processing Ni-based coatings. In this work, the evolution of the local wear behaviour of Inconel 625 laser cladded coatings after high temperature isothermal oxidation treatments have been investigated.The authors would like to thank the Spanish government CICYT through grants MAT2010-18916 and MAT2013-41784-R, the Universidad Rey Juan Carlos project URJC-CM-2010-CET-5550 and the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement number 605207 for financial support

    Nanosized superconducting constrictions

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    Nanowires of lead between macroscopic electrodes are produced by means of an STM. Magnetic fields may destroy the superconductivity in the electrodes, while the wire remains in the superconducting state. The properties of the resulting microscopic Josephson junctions are investigated.Comment: 3 pages,3 eps figures include

    Analysis of spontaneous MEG activity in mild cognitive impairment and Alzheimer's disease using spectral entropies and statistical complexity measures

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    Alzheimer's disease (AD) is the most common cause of dementia. Over the last few years, a considerable effort has been devoted to exploring new biomarkers. Nevertheless, a better understanding of brain dynamics is still required to optimize therapeutic strategies. In this regard, the characterization of mild cognitive impairment (MCI) is crucial, due to the high conversion rate from MCI to AD. However, only a few studies have focused on the analysis of magnetoencephalographic (MEG) rhythms to characterize AD and MCI. In this study, we assess the ability of several parameters derived from information theory to describe spontaneous MEG activity from 36 AD patients, 18 MCI subjects and 26 controls. Three entropies (Shannon, Tsallis and Rényi entropies), one disequilibrium measure (based on Euclidean distance ED) and three statistical complexities (based on Lopez Ruiz–Mancini–Calbet complexity LMC) were used to estimate the irregularity and statistical complexity of MEG activity. Statistically significant differences between AD patients and controls were obtained with all parameters (p < 0.01). In addition, statistically significant differences between MCI subjects and controls were achieved by ED and LMC (p < 0.05). In order to assess the diagnostic ability of the parameters, a linear discriminant analysis with a leave-one-out cross-validation procedure was applied. The accuracies reached 83.9% and 65.9% to discriminate AD and MCI subjects from controls, respectively. Our findings suggest that MCI subjects exhibit an intermediate pattern of abnormalities between normal aging and AD. Furthermore, the proposed parameters provide a new description of brain dynamics in AD and MCI

    Las bibliotecas de los hospitales públicos en España. Un análisis económico

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    ResumenIntroducciónEn el campo de la salud, el constante aumento de la producción científica, el desarrollo de nuevas tecnologías y el incremento en los costes de las publicaciones hacen a las bibliotecas fundamentales en la asistencia, docencia e investigación. En España se perciben deficiencias en las bibliotecas hospitalarias y se desconoce su coste. Por ello, este trabajo analizar el coste de las bibliotecas de hospitales públicos en España y estima el coste de adaptación a estándares internacionales.MétodosEstudio transversal mediante encuesta dirigida a las bibliotecas de los hospitales públicos mayores de 100 camas, o menores con acreditación docente. La información sobre las variables de interés fue recogida mediante un cuestionario enviado a las bibliotecas por correo con seguimiento telefónico. La recogida de datos finalizó en 1996. La información sobre costes se refiere al año 1994. Para examinar el efecto de la imprecisión en las estimaciones y asunciones se realizó un análisis de sensibilidad.ResultadosSe identificaron 314 hospitales, de los cuales 211 (67,2%) tienen biblioteca. El coste de las 211 bibliotecas fue de 3.060 millones de pesetas (coste medio: 14,5 millones de pesetas). Los costes de personal son la partida más importante (38% del total) seguidos del coste de suscripciones (29%). El coste de las bibliotecas hospitalarias supuso el 0,08% del gasto sanitario público nacional. Corregir las infradotaciones, según estándares internacionales, supondría unos 400 millones de pesetas adicionales el primer año (0,01% del gasto sanitario público).ConclusionesEl coste de las bibliotecas hospitalarias supone una pequeña fracción del gasto sanitario público. La corrección de las deficiencias observadas y la relevancia de las bibliotecas en el sistema sanitario requerirían incrementar el gasto hasta casi el 0,1% del gasto sanitario público.SummaryBackgroundThe continuous increase in scientific knowledge in the health field, the development of new technologies and the rising cost of publications means that libraries are essential for patient care, medical education and research. In Spain some deficiencies have been seen in hospital libraries, and their cost is unknown.ObjectiveTo analyze the cost of public hospital libraries in Spain and to estimate the cost of adapting them to international standards.MethodsCross-sectional survey of public hospitals larger than 100 beds, or smaller public hospitals with teaching accreditation. Information on the variables of interest was collected by questionnaire mailed to the libraries and followed up by telephone. Data collection was completed in 1996. The information on costs is for 1994. A sensitivity analysis was done to examine the effects of imprecise estimates and assumptions.ResultsOf the 314 hospitals identified, 211 (67.2%) had libraries. The 1994 cost of the of the 211 libraries was 3,060 million pesetas (mean cost: 14.5 million pesetas). Personnel costs were the most important item (38% of the total), followed by the cost of subscriptions (29%). The cost of hospital libraries represented 0.08% of national public expenditures on health. The cost of correcting inadequacies in accordance with international standards would increase spending by about 400 million pesetas the first year (0.01% of public spending on health).ConclusionsThe cost of hospital libraries represents only a small fraction of public spending on health. Correction of the observed deficiencies and the importance of libraries in the health system would require increasing spending to about 0.1% of public spending on health

    Improving the oscillating wear response of cold sprayed Ti-6Al-4V coatings through a heat treatment

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    Cold spray (CS) coating technique is being studied as a potential solution for repairing aircraft Ti-6Al-4V components. This work is focused on the restoration of damaged components due to wear induced by vibrations. It is known that Ti-6Al-4V CS deposition shows difficulties to obtain non-porous coatings due to the high strength of this material, that is detrimental for wear resistance. In this sense, performing a post-heat treatment leads to lower porosity CS Ti-6Al-4V coatings and improves their mechanical properties, and thus, a better tribological behaviour is also expected. Therefore, the objective of this study was to determine the effect of a post-heat treatment on the wear resistance of Ti-6Al-4V coatings deposited by the CS technique. Ti-6Al-4V CS coatings were used, which have been sprayed with nitrogen as process gas at a temperature of 1100 °C and a pressure of 50 bar. The coatings were subjected to a solution heat treatment followed by a precipitation heat treatment. Oscillating and unidirectional sliding wear experiments were conducted on the coatings at room temperature and at 450 °C. A pin on disc configuration was used with a bearing steel counterbody. The results were compared to those obtained on the substrate (which represents the material to be repaired) and on the as-sprayed coating, which were derived from a previous work. The heat treated coating presented improved wear behaviour as compared to the substrate as well as to the as-sprayed coating, particularly during the high temperature tests. Wear at high temperature was dominated by material transference from the counterbody to the Ti-6Al-4V coating

    Absence of charge backscattering in the nonequilibrium current of normal-superconductor structures

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    We study the nonequilibrium transport properties of a normal-superconductor-normal structure, focussing on the effect of adding an impurity in the superconducting region. Current conservation requires the superfluid velocity to be nonzero, causing a distortion of the quasiparticle dispersion relation within the superconductor. For weakly reflecting interfaces we find a regime of intermediate voltages in which Andreev transmission is the only permitted mechanism for quasiparticles to enter the superconductor. Impurities in the superconductor can only cause Andreev reflection of these quasiparticles and thus cannot degrade the current. At higher voltages, a state of gapless superconductivity develops which is sensitive to the presence of impurities.Comment: Latex file, 11 pages, 2 figures available upon request [email protected], to be published in Journal of Physics: Condensed Matte

    Therapeutic use of monoclonal antibodies

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    La utilización de terapias basadas en anticuerpos monoclonales ha supuesto un gran avance en la práctica clínica. Tienen un ámbito de utilización muy diverso, incluyendo aplicaciones diagnósticas y terapéuticas principalmente. En cuanto a su uso como tratamiento, las áreas más beneficiadas con su descubrimiento han sido la oncología y las enfermedades del sistema inmune.Se trata de un área en continuo crecimiento, tanto por la aparición de nuevos fármacos, como por la ampliación de indicaciones de los ya existentes. Esta revisión resume las características farmacológicas más importantes de los anticuerpos monoclonales comercializados en nuestro país. Se centra principalmente en la utilidad terapeútica, dosificación, eventos adversos de gran relevancia clínica y consideraciones importantes para su correcta administración. También se realiza un breve apunte de las indicaciones de los anticuerpos monoclonales autorizados por la agencia europea del medicamento (EMEA) y que se encuentran en distintas fases del proceso de comercializaciónThe utilization of therapies based on monoclonal antibodies has supposed a great advance in the clinical practice. They have a diverse field of use, including diagnostic and therapeutic applications. As treatment, the most benefited has been the oncology and immune system diseases.This is an area in continuous growth, so much for the appearance of new medicaments, since for the extension of indications of the already existing ones. This review summarizes the most important pharmacological characteristics of the monoclonal antibodies commercialized in our country. It centres principally on the authorized indications, dosing, adverse events of great clinical relevancy and important considerations for his correct administration. Also there is realized a brief note of the indications of the monoclonal antibodies authorized by the European agency of the medicine (EMEA) and that are in different phases of the process of commercialization

    Genome-wide analysis of the H3K27me3 epigenome and transcriptome in brassica rapa

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    Background Genome-wide maps of histone modifications have been obtained for several plant species. However, most studies focus on model systems and do not enforce FAIR data management principles. Here we study the H3K27me3 epigenome and associated transcriptome of Brassica rapa, an important vegetable cultivated worldwide. Findings We performed H3K27me3 chromatin immunoprecipitation followed by high-throughput sequencing and transcriptomic analysis by 3′-end RNA sequencing from B. rapa leaves and inflorescences. To analyze these data we developed a Reproducible Epigenomic Analysis pipeline using Galaxy and Jupyter, packaged into Docker images to facilitate transparency and reuse. We found that H3K27me3 covers roughly one-third of all B. rapa protein-coding genes and its presence correlates with low transcript levels. The comparative analysis between leaves and inflorescences suggested that the expression of various floral regulatory genes during development depends on H3K27me3. To demonstrate the importance of H3K27me3 for B. rapa development, we characterized a mutant line deficient in the H3K27 methyltransferase activity. We found that braA.clf mutant plants presented pleiotropic alterations, e.g., curly leaves due to increased expression and reduced H3K27me3 levels at AGAMOUS-like loci. Conclusions We characterized the epigenetic mark H3K27me3 at genome-wide levels and provide genetic evidence for its relevance in B. rapa development. Our work reveals the epigenomic landscape of H3K27me3 in B. rapa and provides novel genomics datasets and bioinformatics analytical resources. We anticipate that this work will lead the way to further epigenomic studies in the complex genome of Brassica crops

    Modeling Spanish anxiolytic consumption: Economic, demographic and behavioral influences

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    Anxiolytics (AX) are the psychotropic drugs prescribed for the treatment of anxiety and insomnia for 2–4 weeks, for longer periods of consumption (>1 month) may lead to the development of tolerance or addiction. In fact, its prescription was 16% of the total pharmaceutical expenditure in Spain in 2007. This paper deals with the development of a mathematical model describing the dynamic of the addiction to AX for the case study of the Spanish region of Castellón. The reasons believed to cause the development of addicts to AX are the economic situation, the marriage termination and the social contact. The simulations performed to forecast the addicts rate for the period 2010–2014 showed an increase from 6% in 2010 to 14% in 2014 with a fluctuation of about 2% between the possible economic scenarios. Finally, the analysis of sensitivity of the rate of addicts to the fluctuation of the social contact parameters was performed, letting us estimate its impact on the pharmaceutical expenditure.De La Poza, E.; Guadalajara Olmeda, MN.; Jódar Sánchez, LA.; Merello Giménez, P. (2013). Modeling Spanish anxiolytic consumption: Economic, demographic and behavioral influences. Mathematical and Computer Modelling. 57(7):1619-1624. https://doi.org/10.1016/j.mcm.2011.10.020S1619162457
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