3D numerical simulation of slope-flexible system interaction using a mixed FEM-SPH model

Flexible membranes are light structures anchored to the ground that protect infrastructures or dwellings from rock or soil sliding. One alternative to design these structures is by using numerical simulations. However, very few models were found until date and most of them are in 2D and do not include all their components. This paper presents the development of a numerical model combining Finite Element Modelling (FEM) with Smooth Particle Hydrodynamics (SPH) formulation. Both cylindrical and spherical failure of the slope were simulated. One reference geometry of the slope was designed and a total of 21 slip circles were calculated considering different soil parameters, phreatic level position and drainage solutions. Four case studies were extracted from these scenarios and simulated using different dimensions of the components of the system. As a validation model, an experimental test that imitates the soil detachment and its retention by the steel membrane was successfully reproduced

El efecto Pigmalión o el buen samaritano de la educación

p. 64-72Describe el efecto Pigmalion en la educación que consiste en que el docente debe tener una serie de aptitudes que le predispongan para ser capaz de despertar en el alumno el sentimiento motivador de que alguien cree ciegamente en su potencial.S

Gas-phase electrocatalytic conversion of CO2 to chemicals on sputtered Cu and Cu–C catalysts electrodes

A novel gas-phase electrocatalytic cell containing a low-temperature proton exchange membrane (PEM) was developed to electrochemically convert CO2 into organic compounds. Two different Cu-based cathode catalysts (Cu and Cu–C) were prepared by physical vapor deposition method (sputtering) and subsequently employed for the gas-phase electroreduction of CO2 at different temperatures (70–90 °C). The prepared electrodes Cu and Cu–C were characterized by X-ray diffraction (XRD), X-ray photoemission spectroscopy (XPS) and scanning electron microscopy (SEM). As revealed, Cu is partially oxidized on the surface of the samples and the Cu and Cu–C cathodic catalysts were comprised of a porous, continuous, and homogeneous film with nanocrystalline Cu with a grain size of 16 and 8 nm, respectively. The influence of the applied current and temperature on the electro-catalytic activity and selectivity of these materials was investigated. Among the two investigated electrodes, the pure Cu catalyst film showed the highest CO2 specific electrocatalytic reduction rates and higher selectivity to methanol formation compared to the Cu–C electrode, which was attributed to the higher particle size of the former and lower CuO/Cu ratio. The obtained results show potential interest for the possible use of electrical renewable energy for the transformation of CO2 into valuable products using low metal loading Cu based electrodes (0.5 mg Cu cm−2) prepared by sputteringSe desarrolló una nueva celda electrocatalítica en fase gaseosa que contiene una membrana de intercambio de protones (PEM) de baja temperatura para convertir electroquímicamente el CO 2 en compuestos orgánicos. Se prepararon dos catalizadores de cátodo basados ​​en Cu diferentes (Cu y Cu–C) mediante el método de deposición física de vapor (pulverización) y posteriormente se emplearon para la electrorreducción de CO 2 en fase gaseosa a diferentes temperaturas (70–90 °C). Los electrodos Cu y Cu–C preparados se caracterizaron por difracción de rayos X (XRD), fotoemisión de rayos Xespectroscopía (XPS) y microscopía electrónica de barrido (SEM). Como se reveló, el Cu está parcialmente oxidado en la superficie de las muestras y los catalizadores catódicos de Cu y Cu-C estaban compuestos por una película porosa, continua y homogénea con Cu nanocristalino con un tamaño de grano de 16 y 8 nm, respectivamente. Se investigó la influencia de la corriente y la temperatura aplicadas sobre la actividad electrocatalítica y la selectividad de estos materiales. Entre los dos electrodos investigados, la película de catalizador de Cu puro mostró la mayor cantidad de CO 2tasas específicas de reducción electrocatalítica y mayor selectividad para la formación de metanol en comparación con el electrodo de Cu-C, lo que se atribuyó al mayor tamaño de partícula del primero y a la menor relación CuO/Cu. Los resultados obtenidos muestran un potencial interés para el posible uso de energía eléctrica renovable para la transformación de CO 2 en productos valiosos utilizando electrodos basados ​​en Cu de baja carga de metal (0,5 mg Cu cm −2 ) preparados por pulverización catódica

Spanish experience on the design of radon surveys based on the use of geogenic information

One of the requirements of the recently approved EU-BSS (European Basic Safety Standards Directive, EURATOM, 2013) is the design and implementation of national radon action plans in the member states (Annex XVIII). Such plans require radon surveys. The analysis of indoor radon data is supported by the existing knowledge about geogenic radiation. With this aim, we used the terrestrial gamma dose rate data from the MARNA project. In addition, we considered other criterion regarding the surface of Spain, population, permeability of rocks, uranium and radium contain in soils because currently no data are available related to soil radon gas concentration and permeability in Spain. Given that, a Spanish radon map was produced which will be part of the European Indoor Radon Map and a component of the European Atlas of Natural Radiation. The map indicates geographical areas with high probability of finding high indoor radon concentrations. This information will support legislation regarding prevention of radon entry both in dwellings and workplaces. In addition, the map will serve as a tool for the development of strategies at all levels: individual dwellings, local, regional and national administration

Hollow Gold Nanoparticles Produced by Femtosecond Laser Irradiation

[EN] Metallic hollow nanoparticles exhibit interesting optical properties that can be controlled by geometrical parameters. Irradiation with femtosecond laser pulses has emerged recently as a valuable tool for reshaping and size modification of plasmonic metal nanoparticles, thereby enabling the synthesis of nanostructures with unique morphologies. In this Letter, we use classical molecular dynamics simulations to investigate the solid-to-hollow conversion of gold nanoparticles upon femtosecond laser irradiation. Here, we suggest an efficient method for producing hollow nanoparticles under certain specific conditions, namely that the particles should be heated to a maximum temperature between 2500 and 3500 K, followed by a fast quenching to room temperature, with cooling rates lower than 120 ps. Therefore, we describe the experimental conditions for efficiently producing hollow nanoparticles, opening a broad range of possibilities for applications in key areas, such as energy storage and catalysis.This work has been funded by the Spanish Ministry of Science, Innovation and Universities (MICIU) (Grants RTI2018-095844-B-I00, PGC2018-096444-B-I00, and MAT2017-86659-R), the EUROfusion Consortium through Project ENR-IFE19.CCFE-01, and the Madrid Regional Government (Grants P2018/NMT-4389 and P2018/EMT-4437). A.P. is thankful for the support of FONDECYT under Grants 3190123 and 11180557, as well as from Financiamiento Basal para Centros Cientificos y Tecnologicos de Excelencia FB-0807. K.L. acknowledges the support of the Russian Science Foundation (Project 19-19-00683). The authors acknowledge the computer resources and technical assistance provided by the Centro de Supercomputacion y Visualizacion de Madrid (CeSViMa) and the supercomputing infrastructure of the NLHPC (ECM-02). This Letter is based upon work from COST Action TUMIEE (CA17126)Castro-Palacio, JC.; Ladutenko, K.; Prada, A.; Gonzalez-Rubio, G.; Diaz-Nunez, P.; Guerrero-Martinez, A.; Fernández De Córdoba, P.... (2020). Hollow Gold Nanoparticles Produced by Femtosecond Laser Irradiation. The Journal of Physical Chemistry Letters. 11(13):5108-5114. https://doi.org/10.1021/acs.jpclett.0c01233S51085114111

Targeting ribosomal G-quadruplexes with naphthalene-diimides as RNA polymerase I inhibitors for colorectal cancer treatment

Guanine quadruplexes (G4s) are non-canonical nucleic acid structures commonly found in regulatory genomic regions. G4 targeting has emerged as a therapeutic approach in cancer. We have screened naph thalene-diimides (NDIs), a class of G4 ligands, in a cellular model of colorectal cancer (CRC). Here, we identify the leading compound T5 with a potent and selective inhibition of cell growth by high-affinity binding to G4s in ribosomal DNA, impairing RNA polymerase I (Pol I) elongation. Consequently, T5 induces a rapid inhibition of Pol I transcription, nucleolus disruption, proteasome-dependent Pol I catalytic subunit A degradation and autophagy. Moreover, we attribute the higher selectivity of carbohydrate-conjugated T5 for tumoral cells to its preferential uptake through the overexpressed glucose transporter 1. Finally, we succinctly demon strate that T5 could be explored as a therapeutic agent in a patient cohort with CRC. Therefore, we report a mode of action for these NDIs involving ribosomal G4 targeting

Biomechanical analysis of The North Face new running footwear

[EN] Nowadays, one of the most popular sports is running. The footwear is the basic component for running, having a big influence in the sport performance and injury prevention. When a runner selects a pair of running shoes analyzes carefully the features of the diverse models commercialized before buying the ones that best fits his or her needs. The North Face has counted on IBV to analyze the biomechanical behavior of different running footwear models.[ES] Uno de los deportes más populares en la actualidad es la carrera, también conocida por su término anglosajón running. El calzado es un componente básico para la práctica del running, teniendo una gran influencia en el rendimiento y la prevención de lesiones. Cuando un corredor selecciona su calzado analiza al detalle las prestaciones de los distintos modelos para adquirir el que mejor se adapte a sus necesidades. THE NORTH FACE ha contado con los servicios del IBV para analizar el comportamiento biomecánico de diferentes modelos de zapatillas de running.Puigcerver Palau, SA.; Gonzalez Garcia, JC.; Piqueras Fiszman, P.; Medina Ripoll, E.; Ballester Fernandez, A.; Fayos Sancho, J.; Solves Camallonga, C.... (2013). Biomecánica aplicada al nuevo calzado de running de The North Face. Revista de biomecánica. 59:23-26. http://hdl.handle.net/10251/38640S23265

Deslizamientos submarinos y tsunamis en el Mar de Alborán. Un ejemplo de modelización numérica

Texto científico de carácter divulgativo.Texto científico de carácter divulgativo en el que se presenta un trabajo de modelado matemático y simulación numérica de un hipotético tsunami producido en el Mar de Alborán por un deslizamiento masivo de materiales en el flanco sur de la Dorsal de Alborán.Instituto Español de Oceanografía. Universidad de Málaga

Blood stasis imaging predicts cerebral microembolism during acute myocardial infarction

Background: Cardioembolic stroke is a major source of mortality and disability worldwide. The authors hypothesized that quantitative characterization of intracardiac blood stasis may be useful to determine cardioembolic risk in order to personalize anticoagulation therapy. The aim of this study was to assess the relationship between image-based metrics of blood stasis in the left ventricle and brain microembolism, a surrogate marker of cardiac embolism, in a controlled animal experimental model of acute myocardial infarction (AMI). -- Methods: Intraventricular blood stasis maps were derived from conventional color Doppler echocardiography in 10 pigs during anterior AMI induced by sequential ligation of the mid and proximal left anterior descending coronary artery (AMI-1 and AMI-2 phases). From these maps, indices of global and local blood stasis were calculated, such as the average residence time and the size and ratio of contact with the endocardium of blood regions with long residence times. The incidence of brain microemboli (high-intensity transient signals [HITS]) was monitored using carotid Doppler ultrasound. -- Results: HITS were detected in 0%, 50%, and 90% of the animals at baseline and during AMI-1 and AMI-2 phases, respectively. The average residence time of blood in the left ventricle increased in parallel. The residence time performed well to predict microemboli (C-index = 0.89, 95% CI, 0.75–1.00) and closely correlated with the number of HITS (R = 0.87, P < .001). Multivariate and mediation analyses demonstrated that the number of HITS during AMI phases was best explained by stasis. Among conventional echocardiographic variables, only apical wall motion score weakly correlated with the number of HITS (R = 0.3, P = .04). Mural thrombosis in the left ventricle was ruled out in all animals. -- Conclusions: The degree of stasis of blood in the left ventricle caused by AMI is closely related to the incidence of brain microembolism. Therefore, stasis imaging is a promising tool for a patient-specific assessment of cardioembolic risk.This study was supported by grant PI15/02211, Rio Hortega (CM17/00144), and Juan Rodés fellowships (JR15/00039) from Instituto de Salud Carlos III; grant DPI2016-75706-P and a Juan de la Cierva fellowship (IJCI-2014-19507) from Ministerio de Economía y Competitividad; synergy grant Y2018/BIO-4858-PREFI-CM from Comunidad Autónoma de Madrid; the European Union - European Regional Development Fund; by the Spanish Society of Cardiology (ISBI-DCM); by the University of California,San Diego, CTRI Galvanizing Engineering and Medicine Program; American Heart Association grant 16GRNT27250262; and National Institutes of Health UC CAI grant CII4560. P.M.-L. was also funded by CIBERCV. P.M.-L., L.R., J.C.A., and J.B. are inventors of a method for quantifying intracardiac stasis from imaging data under a Patent Cooperation Treaty patent application (WO2017091746A1)