683 research outputs found

    SEM-EDX study of bentonite alteration under the influence of cement alkaline solutions

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    Bentonite is a key barrier for the isolation of high-level radioactive waste within Deep Geological Repository. However, bentonite may be altered by contact with cementitious materials and their alkaline pore fluids. This study offers an extensive morphological and semi-quantitative characterization of the bentonite surface exposed to three types of alkaline pore fluids released by different cement-based materials. The bentonite surfaces were studied using a thorough scanning electron microscopy exploration and analysed using an energy-dispersive ꭕ-ray detector (SEM-EDX). In addition, statistical, element mappings, ꭕ-ray diffraction and infrared spectroscopy analyses were performed. The aim was to have a picture of the morphological and chemical alterations of bentonite at very early stages in accordance with the integrated approach necessary to address bentonite stability in the long-term. As a consequence of the reactivity, two types of morphologies stood out in the matrix of bentonite: platelets and coatings-like crusts characterized by their high Mg and Ca content. These alterations presented a different scope depending on the type of alkaline pore solution involved and suggested the precipitation of authigenic magnesium silicate hydrates (M-S-H) and/or trioctahedral clay minerals and Ca‑carbonates. The knowledge of the performance of bentonite subjected to these alkaline solutions can help in the evaluation of the most suitable cement-based materials to be used next to bentoniteThe experimental work was supported by funding from the European Union‘s Horizon 2020 Research and Training programme from EURATOM [H2020-NFRP 2014, 2015] under grant agreement n◦662147; CEBAM

    Generación de ambientes para entrenamiento en seguridad informática

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    Los ataques informáticos son un tema latente en la actualidad. Para poder contrarrestar los riegos, es necesario contar con profesionales informáticos especializados en seguridad. Dichos profesionales deben de ser capaces de entender cuales son los riesgos, las amenazas y las vulnerabilidades a las que se están enfrentando. Para ello necesitan aprender tanto como sea posible de los problemas, y poder articular respuestas rápidas ante incidentes de seguridad. En este contexto, poder contar con ambientes de entrenamiento en los cuales se puedan experimentar con técnicas, herramientas y problemas reales es fundamental. Sin embargo, si se hace en forma manual, la creación y el mantenimiento de este tipo de ambientes se torna una tarea compleja y que consume mucho tiempo. Esto motiva el desarrollo de una herramienta que asista en la generación de ambientes para entrenamiento en seguridad informática. En este artículo se describe la arquitectura de una herramienta orientada a solucionar la problemática planteada. Como parte del diseño, se definió un lenguaje de especicación de prácticas de seguridad, que permite la declaración e instanciación de escenarios. Los escenarios, generados apartir de la especicación, emulan de manera dedigna los ambientes de producción reales y permiten emplear herramientas comúnmente utilizadas en el mercado

    Caracterización y degradación de los materiales graníticos de la Colegiata de San Isidro, Madrid, España

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    Original granitoids from the façade of the Colegiata de San Isidro are medium-grained-biotitic adamellites, from quarries of the Valdemorillo area (Madrid). The petrophysical properties of the materials allow to establish a clear difference between the two original granites: the most abundant one (A), with a lower porosity, lower water sorption capacity, a lower water vapour permeability coefficient, a higher ultrasonic waves transmission velocity, and a higher strength, respect to the least abundant granite (B). So it can be said the former is more resistant and of better quality than B-granite, or in other words, is a less-alterable granite than B-granite. In relation to the granites alteration trend, data make possible to establish that A-granite suffers less alteration than B-granite, because in the latter, values of the properties determined in internal and external sections, vary much more than for the A-granite. A brief reference to the conservation state of the main façade and to the monitoring of the atmospheric pollutants registered by two stations close to the building, with the aim of determining its inluence on the material degradation, which mainly consists of soiling and blackenning

    Seguridad informática en la Universidad de la República

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    Este artículo presenta al Grupo de Seguridad Informática de la Facultad de Ingeniería de la Universidad de la República (Uruguay), creado en 2006. Se describen los trabajos de investigación del grupo y los resultados generados, proveyendo referencias a sus artículos publicados. Se incluye asimismo una breve descripción de la actividad de formación curricular universitaria a cargo del equipo

    Ajustando RFR por Preditores de Discordância, “The Adjusted RFR”: Uma Metodologia Alternativa para Melhorar a Capacidade Diagnóstica de Índices Coronarianos

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    Background: Cutoff thresholds for the "resting full-cycle ratio" (RFR) oscillate in different series, suggesting that population characteristics may influence them. Likewise, predictors of discordance between the RFR and fractional flow reserve (FFR) have been documented. The RECOPA Study showed that diagnostic capacity is reduced in the RFR "grey zone", requiring the performance of FFR to rule out or confirm ischemia. Objectives: To determine predictors of discordance, integrate the information they provide in a clinical-physiological index, the "Adjusted RFR", and compare its agreement with the FFR. Methods: Using data from the RECOPA Study, predictors of discordance with respect to FFR were determined in the RFR "grey zone" (0.86 to 0.92) to construct an index ("Adjusted RFR") that would weigh RFR together with predictors of discordance and evaluate its agreement with FFR. Results: A total of 156 lesions were evaluated in 141 patients. Predictors of discordance were: chronic kidney disease, previous ischemic heart disease, lesions not involving the anterior descending artery, and acute coronary syndrome. Though limited, the "Adjusted RFR" improved the diagnostic capacity compared to the RFR in the "grey zone" (AUC-RFR = 0.651 versus AUC-"Adjusted RFR" = 0.749), also showing an improvement in all diagnostic indices when optimal cutoff thresholds were established (sensitivity: 59% to 68%; specificity: 62% to 75%; diagnostic accuracy: 60% to 71%; positive likelihood ratio: 1.51 to 2.34; negative likelihood ratio: 0.64 to 0.37). Conclusions: Adjusting the RFR by integrating the information provided by predictors of discordance to obtain the "Adjusted RFR" improved the diagnostic capacity in our population. Further studies are required to evaluate whether clinical-physiological indices improve the diagnostic capacity of RFR or other coronary indices.Fundamento: Os limiares de corte para a “relação do ciclo completo de repouso” (RFR) oscilam em diferentes séries, sugerindo que as características da população podem influenciá-los. Da mesma forma, foram documentados preditores de discordância entre a RFR e a reserva de fluxo fracionado (FFR). O Estudo RECOPA, mostrou que a capacidade diagnóstica está reduzida na “zona cinzenta” da RFR, tornando necessária a realização de FFR para descartar ou confirmar isquemia. Objetivos: Determinar os preditores de discordância, integrar as informações que eles fornecem em um índice clínico-fisiológico: a “RFR Ajustada”, e comparar sua concordância com o FFR. Métodos: Usando dados do Estudo RECOPA, os preditores de discordância em relação à FFR foram determinados na “zona cinzenta” da RFR (0,86 a 0,92) para construir um índice (“RFR Ajustada”) que pesaria a RFR juntamente com os preditores de discordância e avaliar sua concordância com a FFR. Resultados: Foram avaliadas 156 lesões em 141 pacientes. Os preditores de discordância foram: doença renal crônica, cardiopatia isquêmica prévia, lesões não envolvendo a artéria descendente anterior esquerda e síndrome coronariana aguda. Embora limitada, a “RFR Ajustada” melhorou a capacidade diagnóstica em comparação com a RFR na “zona cinzenta” (AUC-RFR = 0,651 versus AUC-“RFR Ajustada” = 0,749), mostrando também uma melhora em todos os índices diagnósticos quando foram estabelecidos limiares de corte otimizados (sensibilidade: 59% a 68%; especificidade: 62% a 75%; acurácia diagnóstica: 60% a 71%; razão de verossimilhança positiva: 1,51 a 2,34; razão de verossimilhança negativa: 0,64 a 0,37). Conclusões: Ajustar a RFR integrando as informações fornecidas pelos preditores de discordância para obter a “RFR Ajustada” melhorou a capacidade diagnóstica em nossa população. Mais estudos são necessários para avaliar se os índices clínico-fisiológicos melhoram a capacidade diagnóstica da RFR ou de outros índices coronarianos

    Torymus sinensis Kamijo, a biocontrol agent against the invasive chestnut gall wasp Dryocosmus kuriphilus Yasumatsu in Spain: its natural dispersal from France and first data on establishment after experimental releases

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    Aim of study: The globally invasive gall wasp, Dryocosmus kuriphilus Yasumatsu, 1951 (Cynipidae: Cynipini), reached Spain seven years ago and is already regarded as an important pest of chestnuts (Castanea spp.) in this country as well as worldwide. In this paper, we present comprehensive data on the establishment in Spain of Torymus sinensis Kamijo, 1982 (Chalcidoidea: Torymidae), an effective non-native natural enemy of this pest, as a result of both natural dispersal and settlement after controlled releases since 2015. Area of study: Sites of the Spanish autonomous communities of Galicia, Asturias, Basque Country, Catalonia, Andalusia and Madrid where D. kuriphilus is present. Material and methods: To study the natural dispersal of T. sinensis from France, we selected two sampling sites in Catalonia, six in the Basque Country and two in Navarra known for their heavy Asian chestnut gall wasp (ACGW) infestation; to study T. sinensis establishment after authorized controlled releases by the concerned authorities, the field samplings were done mainly in Galicia (35 sites) and Andalusia (8 sites). Additionally an experimental release study was made in Madrid. Main Results: Our results showed that T. sinensis has spread throughout Spain by natural dispersal across the French border and now occurs in Catalonia (two sites), the Basque Country (three sites) and Navarra (one site) but not in the neighbouring region of Cantabria. The percentage of parasitism by T. sinensis on D. kuriphilus is higher in the Basque Country sites, which are close to the French border, thus indicating that its establishment in these localities is not recent. After controlled releases, T. sinensis has been successfully established in five release sites in Andalusia (Valle del Genal and Sierra Blanca, Málaga Province) and one release site in Madrid. However, in the region of Galicia (NW Spain), where the number of authorized releases has been higher, the establishment of T. sinensis still appears to be very low. Research highlights: Established populations of T. sinensis may exert a positive buffer against D. kuriphilus-driven chestnut infestation in Spain, similar to what is observed in other invaded European countries.This study was financed by an Encomienda de Gestión from MAPAMA to Agencia Estatal CSIC, 16MNES003 awarded to JLNA, DGT, MJL and CP, and by project AGL2016-76262-R (AEI/FEDER, UE) awarded to MJL and JLNA. JRB, JMV, MEW and OG were supported by project PP.PEI.IDF201601.4 de Demanda Institucional from CMAOT to the public research Institution IFAPA. CP was funded by a post-doctoral contract from the Universidad de Castilla-La ManchaS

    Silver clusters of five atoms as highly selective antitumoral agents through irreversible oxidation of thiols

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    Low atomicity clusters present properties dependent on the size, due to the quantum confinement, with well-defined electronic structures and high stability. Here it is shown that Ag5 clusters catalyze the complete oxidation of sulfur to S+6. Ag5 catalytic activity increases with different oxidant species in the order O2 ≪ H2O2 < OH•. Selective oxidation of thiols on the cysteine residues of glutathione and thioredoxin is the primary mechanism human cells have to maintain redox homeostasis. Contingent upon oxidant concentration, Ag5 catalyzes the irreversible oxidation of glutathione and thioredoxin, triggering apoptosis. Modification of the intracellular environment to a more oxidized state to mimic conditions within cancer cells through the expression of an activated oncogene (HRASG12V) or through ARID1A mutation, sensitizes cells to Ag5 mediated apoptosis. While cancers evolve to evade treatments designed to target pathways or genetic mutations that drive them, they cannot evade a treatment that takes advantage of aberrant redox homeostasis, which is essential for tumor progression and metastasis. Ag5 has antitumor activity in mice with orthotopic lung tumors reducing primary tumor size, and the burden of affected lymphatic nodes. The findings suggest the unique intracellular redox chemistry of Ag5 may lead to new redox-based approaches to cancer therapyThis research was partially supported by 1) “la Caixa” Foundation, Ref. LCF/PR/PR12/11070003 to F.D. and M.A.L.Q.; 2) Ministerio de Ciencia, Innovación y Universidades (MAT2017-89678-R, AEI/FEDER, UE) to F.D. and A.V.; 3) the Consellería de Educación (Xunta de Galicia), Grants No. Grupos Ref. Comp. ED431C 2017/22, ED431C 2019/13 and AEMAT-ED431E2018/08 to M.A.L.Q.; and ED431C 2019/13 to A.V. This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme (Bac-To-Fuel) under Grant Agreement No. 825999 (M.A.L.Q.). J.C.H. acknowledge financial support from European Union's Horizon 2020 research and innovation programme under grant agreement no. 823717-ESTEEM3, and the MICIIN (projects PID2019-107578GA-100 and PID-110018GA-100). J.M.D, L.J.G., and F.G.R. thank to the ANPCyT (PICT 2015-2285 and 2017-3944), UNLP (Project 11/X790) and the partial support by the Laboratório Nacional de Luz Síncrotron (LNLS, Brazil) under proposal SXS-20180280. G.B. acknowledges the CINECA Award N. IsC51, year 2017, under the ISCRA initiative, for the availability of high-performance computing resources and support. D.B. expresses gratitude for a postdoctoral grant from Xunta de Galicia, Spain (POS-A/2013/018). B.D. expresses gratitude for a predoctoral grant from MICINN, Spain (BES-2016-076765). F.D. and A.V. also acknowledged Xunta de Galicia (Centro singular de investigación de Galicia accreditation 2019-2022 ref ED431G 2019/02) and the European Union (European Regional Development Fund – ERDF). Work in M.P.M.'s lab was supported by the Medical Research Council UK (MC_U105663142). T.G.C. gratefully acknowledges the technical assistance of María José Otero-Fraga (FIDIS)S

    Avances en Informática y Automática. Décimo Workshop

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    [ES]El Máster Oficial en Sistemas Inteligentes de la Universidad de Salamanca tiene como principal objetivo promover la iniciación de los estudiantes en el ámbito de la investigación. El congreso organizado por el Departamento de Informática y Automática que se celebra dentro del Máster en Sistemas Inteligentes de la Universidad de Salamanca proporciona la oportunidad ideal para que sus estudiantes presenten los principales resultados de sus Trabajos de Fin de Máster y obtengan una realimentación del interés de los mismos. La décima edición del workshop “Avances en Informática y Automática”, correspondiente al curso 2015 - 2016, ha sido un encuentro interdisciplinar donde se han presentado trabajos pertenecientes a un amplio abanico de líneas de investigación, desde los sistemas biométricos y la visualización de la información hasta la minería de datos pasando por otros campos relacionados. Todos los trabajos han sido supervisados por investigadores de reconocido prestigio pertenecientes a la Universidad de Salamanca, proporcionando el marco idóneo para sentar las bases de una futura tesis doctoral. Entre los principales objetivos del congreso se encuentran: Ofrecer a los estudiantes un marco donde exponer sus primeros trabajos de investigación. Proporcionar a los participantes un foro donde discutir ideas y encontrar nuevas sugerencias de compañeros, investigadores y otros asistentes a la reunión. Permitir a cada estudiante una realimentación de los participantes sobre su trabajo y una orientación sobre las futuras direcciones de investigación. Contribuir al desarrollo del espíritu de colaboración en la investigación
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