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Abstract Copper is an active electrocatalyst for various energy conversion reactions, but its performance depends on the structure of the active surface sites. In this work, we propose a simple strategy to tailor both the roughness and the active site's geometry of copper. To modify the surface of copper, we oxidize and reduce a copper polycrystalline electrode in 0.1 M solutions containing both sodium fluoride and sodium chloride with different chloride/fluoride molar ratios: (0.1‐x) M NaF+x M NaCl. To address the anion effect on the changes in surface geometry, we recorded the voltammetric fingerprints of the modified electrodes using lead underpotential deposition (UPD). The voltammetric analysis suggested that while chloride induces (n10) sites, fluoride promotes an increase in the active surface area and the growth of low‐coordinated sites with (110) or (111) geometry. Solutions containing both fluoride and chloride anions induced (n10) motifs covered by nanometric clusters, as observed by scanning electron microscopy, forming a highly defect‐rich surface. Our work provides a direct link between electrochemical response and ex‐situ structural characterization, and compares, in detail, the effect of chloride and fluoride on the surface nanostructuring of copper.

Percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) are the main interventional treatments for coronary artery disease (CAD) patients. Both procedures are constantly being perfected and developed. This study aims to analyze the evolution of intervention mortality rates of PCI and CABG in recent years in Spain. We use a database of all hospital discharges from CABG and PCI procedures in Spain during two periods, between the years 2010 to 2012 and 2016 to 2019. We elaborate two multivariate regression logistic models to test the differences in mortality between the two periods and the two procedures, adjusting the mortality rates by age, gender, and comorbidities. We find strong evidence that CABG significantly reduced mortality rates, especially in complex patients, while PCI remained almost constant. We also discuss how physicians incorporate the improvement in procedures’ performance into the decision-making for the recommendation of these two procedures in CAD patient management.

In the framework of the wind energy network for distributed generation in urban environments for most South American countries, wind resource assessment studies have been carried out in activities to establish a suitable methodology to assess the wind potential in urban environments. Some methodologies are already published in research studies, and the wind tunnel is the most accurate solution to obtain insight into the wind resource when measurements are unavailable, which is the most frequent case. Nevertheless, besides its validity, one cannot disregard the high cost of producing a scaled urban model and access to a wind tunnel. In this sense, this paper compares results from a wind tunnel experiment and different numerical modeling approaches. Two commercial models (WindSim and Wasp Engineering) and one open-source CFD code (OpenFOAM) are used. The results from the modeling simulation concluded that CFD models could achieve lower deviations for the mean wind speed and turbulence intensity when compared with non-CFD models. With such results, CFD modeling is a promising tool for reliably evaluating wind potential in urban environments.

Introduction: This study aimed to develop an individualized artificial intelligence model to help radiologists assess the severity of COVID-19’s effects on patients’ lung health.Methods: Data was collected from medical records of 1103 patients diagnosed with COVID-19 using RT- qPCR between March and June 2020, in Hospital Madrid-Group (HM-Group, Spain). By using Convolutional Neural Networks, we determine the effects of COVID-19 in terms of lung area, opacities, and pulmonary air density. We then combine these variables with age and sex in a regression model to assess the severity of these conditions with respect to fatality risk (death or ICU).Results: Our model can predict high effect with an AUC of 0.736. Finally, we compare the performance of the model with respect to six physicians’ diagnosis, and test for improvements on physicians’ performance when using the prediction algorithm.Discussion: We find that the algorithm outperforms physicians (39.5% less error), and thus, physicians can significantly benefit from the information provided by the algorithm by reducing error by almost 30%.

The use of advanced generation III+ and IV nuclear reactors, and their applications, has become important, seen as a means capable of contributing to the global transition to more sustainable, affordable and reliable energy systems. This technology, which could be integrated into future carbon-free electric power generation systems with high proportions of different renewable energy sources, includes Small Modular Reactors (SMR). There are about 100 different proposed projects of Generation III+ and IV, of which about 50 are SMR concepts, in various stages of development and of different types of technologies. Other important issues for achieving the long-term sustainability of nuclear energy are the proper use of its fuel sources and the improvement of nuclear waste management. Therefore, fuels based on a mixture of oxides have been used successfully in several countries. In addition, the incorporation of thorium-based fuel is a current challenge for the new designs of advanced reactors. The present paper focuses on the analysis of a small modular integral pressurized water reactor (iPWR) with Thorium-Uranium Oxide (Th-U MOX) mixtures. A thermohydraulic model is developed using the Ansys CFX program, which allows the calculation of the temperature distribution in the section where the highest power is produced within the SMR IPWR core (critical section). The temperature distributions in the fuel, clad and coolant were calculated with the objective of verifying that they were within the safety limits.

A new cathode material, FeS2-decorated carbon nanofiber (CNF), is proposed for Li-S batteries. The structure and physicochemical properties of the material have been engineered to enhance the poor cycling stability typically displayed by sulfur composites. The composite material shows a complex architecture with a matrix of CNF hosting the sulfur and core-shell FeS2 nanoparticles acting as a catalyst for a solid phase conversion-type reaction. This cathode delivers high discharge capacities of 864, 798, 689, 595 and 455 mAhg−1 at C/10, C/5, C/2, 1C and 2C, respectively, with a stable capacity retention of 87% at 2C after 300 cycles. FeS2-decorated CNF has been characterised using several techniques, including in-situ battery measurements at the ALBA synchrotron facility and high-throughput microscopy, giving valuable insights into its charge/discharge reaction mechanism. The excellent performance obtained is combined with the use of just low-cost and abundant elements such as iron, sulfur and carbon, which makes this battery highly promising for the next generation of electrochemical energy storage devices.

Copper is an active electrocatalyst for various energy conversion reactions, but its performance depends on the structure of the active surface sites. In this work, we propose a simple strategy to tailor both the roughness and the active site's geometry of copper. To modify the surface of copper, we oxidize and reduce a copper polycrystalline electrode in 0.1 M solutions containing both sodium fluoride and sodium chloride with different chloride/fluoride molar ratios: (0.1‐x) M NaF+x M NaCl. To address the anion effect on the changes in surface geometry, we recorded the voltammetric fingerprints of the modified electrodes using lead underpotential deposition (UPD). The voltammetric analysis suggested that while chloride induces (n10) sites, fluoride promotes an increase in the active surface area and the growth of low‐coordinated sites with (110) or (111) geometry. Solutions containing both fluoride and chloride anions induced (n10) motifs covered by nanometric clusters, as observed by scanning electron microscopy, forming a highly defect‐rich surface. Our work provides a direct link between electrochemical response and ex‐situ structural characterization, and compares, in detail, the effect of chloride and fluoride on the surface nanostructuring of copper. [ABSTRACT FROM AUTHOR]

A energia nuclear é uma das principais alternativas para futuras fontes de energia sem emissões de gases contribuintes ao efeito estufa. Neste contexto os reatores nucleares modulares de pequeno porte têm grande potencial de desenvolvimento. Nesta categoria, por suas características de segurança e semelhanças com os reatores atuais em operação, destacam-se os reatores integrais de água pressurizada (iPWR). Neste trabalho, é apresentado um modelo computacional neutrônico baseado no código Monte Carlo Serpent para o projeto e análise de um ciclo de combustível estendido de quatro anos em um reator de tipo iPWR. Os principais parâmetros do comportamento neutrônico do núcleo são calculados e comparados com as recomendações para retores refrigerados a água.

The nuclear energy is a good alternative to meet the continuous increase in world energy demand. In this pers-pective, VHTRs (Very High Temperature Reactors) are serious candidates for energy generation due to its inherently safe performance, low power density and high conversion efficiency. However, the viability of these reactors depends on an efficient safety system in the operation of nuclear plants. The HTR (High Temperature Reactor)-10 model, an experimental reactor of the pebble bed type, is used as a case study in this work to perform the thermohydraulic simulation. Due to the complex patterns flow that appear in the pebble bed reactor core CFD (Computational Fluid Dynamics) techniques are used to simulate these reactors. A realistic approach is adopted to simulate the central annular column of the reactor core. As geometrical model of the fuel elements was selected the BCC (Body Centered Cubic) arrangement. Parameters considered for reactor design are available in the technical report of benchmark issues by IAEA (TECDOC-1694). We obtain the temperature profile distribution in the core for regimes where the coolant flow rate is smaller than recommended in a normal operation. In general, the temperature distributions calculated are consistent with phenomenological behavior. Even without considering the reactivity changes to reduce the reactor power or other safety mechanisms, the maximum temperatures do not exceed the recommended limits for TRISO fuel elements.

In an iPWR (integral pressurized water reactor), the pressurizer is located at the top of the reactor vessel; this configuration requires the investigation of the mechanisms adopted for the homogenization of boron. In previous work, three representative experiments were conducted in an experimental installation made of stainless steel with a volumetric scale equal to 1:200, representing one-fourth of the pressurizer of an iPWR. The test facility layout was mounted so that the test section was fed with water or saline solutions with different concentrations, representing scenarios of boration or deboration. To determine the concentration at the inlet and outlet of the test section, samples have been collected every 10 min during the experiments representing some scenarios. The main goal in this work was to investigate how well mixing during boron dilution transients in the pressurizer of a small modular reactor can be modelled accurately by CFD (Computational Fluid Dynamics) codes. Two CFD codes were used, the commercial ANSYS CFX and the open source CFD code OpenFOAM. The use of open source software such as OpenFOAM offers a way to CFD gain acceptance in the licensing. The results of the comparison of simulations with an experiment at the test section were presented and showed a very good agreement. It was verified that deviations are less than 4%, both codes can be used to accurately represent this phenomenon. In order to improve future experiments, the dispersion of the solution inside the test section is studied with the aim to propose positions for sensors. A first simple configuration is proposed, but some further simulations will be done to find an optimum configuration.

The Very High Temperature Reactor (VHTR) is one of the candidates of next generation of the nuclear reactors according to IAEA. Predicting the thermohydraulic behavior of High Temperature Reactors (HTR) is an important contribution to the development of this technology. Evaluation of thermohydraulic performance and a comparison with experimental data were proposed to the international research community. The impact of porosity of pebble beds in the thermohydraulic performance in normal operation and under accident condition is the goal of many kinds of research. In this sense, the three-dimensional CFD thermohydraulic simulation of a HTR using ANSYS CFX has been done. The full-scale approach is used to study the influence of different porosity scheme in the main structural materials of the HTR-10 reactor. The porous medium model was used to simulate the pebble bed core zone and the discharge system of pebbles. A comparison with experimental data was made. The steady-state thermohydraulic performance of the HTR-10 reactor at normal operation and anticipated transients without scram (ATWS) tests result, were used. In this work, was possible to estimate the effect of the porosity in the interior regions of the reactor and the impact on the temperature distribution. Finally, the study broadens the knowledge about the impact that the use of variable porosity has on safety analyses in pebble beds reactors.

Introduction and objective: The interest in improving the quality of care has led to the implementation of the International Organization for Standardization (ISO) 9001:2015 standard in the Child and Adolescent Psychiatry Unit of the Santiago de Compostela University Clinical Hospital (A Coruña, Spain). The objective of this work is to describe the methodology developed to obtain it, as well as the perceived experience of the process. Method: The steps carried out were: creation of a multidisciplinary quality work group and a work schedule; preparation of the Quality Manual, Process Map and definition of the scope of the Quality Management System; preparation and planning of satisfaction surveys; definition of operational and care processes; context and stakeholder analysis; definition of the risks and opportunities of the quality system; establishment of quality measurement indicators; establishment of actions to promote continued training; review of the quality system by the hospital management; and planning of the improvement objectives. Results: The agreed schedule was met, completing all the established tasks in a period of approximately 15 months. Finally, an evaluation of compliance with requirements/results was carried out through an internal and external audit, after which certification of the Unit was achieved according to the ISO 9001:2015 standard. Discussion and Conclusions: The implementation of the ISO standard should be considered the beginning of a working method that ensures continuous improvement, teamwork and establishes a culture of quality in the Unit through continuous monitoring of its activity. [ABSTRACT FROM AUTHOR]

Objective: To describe the capacity of a broad spectrum of cytokines and growth factors to predict ICU admission and/or death in patients with severe COVID-19. Design: An observational, analytical, retrospective cohort study with longitudinal follow-up. Setting: Hospital Universitario Príncipe de Asturias (HUPA). Participants: 287 patients diagnosed with COVID-19 admitted to our hospital from 24 March to 8 May 2020, followed until 31 August 2020. Main outcome measures: Profiles of immune response (IR) mediators were determined using the Luminex Multiplex technique in hospitalized patients within six days of admission by examining serum levels of 62 soluble molecules classified into the three groups: adaptive IR-related cytokines (n = 19), innate inflammatory IR-related cytokines (n = 27), and growth factors (n = 16). Results: A statistically robust link with ICU admission and/or death was detected for increased serum levels of interleukin (IL)-6, IL-15, soluble (s) RAGE, IP10, MCP3, sIL1RII, IL-8, GCSF and MCSF and IL-10. The greatest prognostic value was observed for the marker combination IL-10, IL-6 and GCSF. Conclusions: When severe COVID-19 progresses to ICU admission and/or death there is a marked increase in serum levels of several cytokines and chemokines, mainly related to the patient’s inflammatory IR. Serum levels of IL-10, IL-6 and GCSF were most prognostic of the outcome measure.

The pedagogical work of this young man from Santiago was not limited to the classroom; he practiced sports next to their students, especially the basketball. It attended with them to trips and he carried out visits to factories following the principle of Martí that, since one lives, fair it is that he becomes trained to know the life. Their work like teacher was not extensive, since single work three school courses; but they were enough to deploy an efficient work that made it accumulate an experience of advanced, guided to the formation of native feelings, of moral convictions of humanism, collaboration, disciplines that are integrated in the personality of the Cuban; securing their identity, at the same time that he is Latin- Americanism and anti-imperialist. It is for it that with this work, Frank País García, teacher, we want to highlight the qualities of this young man from Santiago.

The Spanish conservative politician José Calvo Sotelo was a finance minister during the dictatorship of Primo de Rivera and one of the main right-wing political figures of the monarchy of Alfonso XIII during the Second Spanish Republic. Through his discourses and essays he developed an economic thought integrating nationalistic and interventionist postulates and a solid defense of private property and austerity, his main goal being to guarantee the independence of the Spanish economy. Some of his thoughts are a subject for debate in today’s crisis.

El uso del agua supercrítica como refrigerante en los reactores nucleares es un reto para su diseño y operación, pues es necesario tener en cuenta la fuerte influencia de las propiedades termodinámicas del agua supercrítica enlas propiedades moderadoras de los neutrones. En este trabajo se desarrolló una metodología basada en un código de Monte-Carlo para el cálculo neutrónico y un código de Dinámica de Fluido Computacional para el cálculo termohidráulico, con el objetivo de realizar el cálculo acoplado neutrónico-termohidráulico de un conjunto combustible de un Reactor de Agua Supercrítica de Alto Desempeño. Empleando la metodología desarrollada fueronobtenidos los perfiles de temperatura y potencia liberada en las barras combustibles del conjunto, los de temperatura en la envoltura de los elementos combustibles y los perfiles de temperatura y densidad del agua en la zona refrigerante y en la zona moderadora del conjunto. Los resultados describen acertadamente el comportamiento de dichos parámetros en el conjunto combustible promedio.

El Sistema de Evaluación y Acreditación de la Educación Superior establecido por la Junta de Acreditación Nacional en Cuba evalúa para los diferentes programas académicos cinco variables claves: pertinencia e impacto social, claustro, estudiantes, infraestructura y currículo. La variable claustro se enfoca en revelar toda la in formación pertinente que fundamenta la calidad del mismo, por lo que se necesita recopilar y evidenciar un volumen importante de datos e información. La presente investigación desarrollada en la Universidad de Ciencias Médicas de Cienfuegos, posee como objetivo fundamental el desarrollo de un sistema informático para la gestión de la información relacionada con la variable claustro según los criterios establecidos por la Junta de Acreditación Nacional en su Sistema de Evaluación y Acreditación. Para ello se utiliza la metodología de desarrollo de software seguida fue Rational Unified Process y el lenguaje de modelado Unified Modeling Language. Como herramienta principal se estableció: Visual Paradigm para UML 8.0 Enterprise Edition para la modelación los requerimientos. Como principal resultado se obtiene un software para gestionar toda la información del claustro de los diferentes programas académicos de la Educación Superior en Cuba. Palabras clave: sistema informático, evaluación, acreditación, educación superior. ABSTRACT The Higher Education Evaluation and Accreditation System established by the National Accreditation Board in Cuba assesses five key variables for the different academic programs: relevance and social impact, faculty, students, infrastructure, and curriculum. The cloister variable focuses on revealing all the pertinent information that underpins its quality, so it is necessary to collect and evidence a significant volume of data and information. The present research developed at the University of Medical Sciences of Cienfuegos, has as its main objective the development of a computer system for the management of information related to the cloister variable according to the criteria established by the National Accreditation Board in its Evaluation and Accreditation. For this, the software development methodology followed was Rational Unified Process and the Unified Modeling Language modeling language. The main tool was Visual Paradigm for UML 8.0 Enterprise Edition for modeling the requirements. As the main result, a software is obtained to manage all the information of the cloister of the different academic programs of Higher Education in Cuba. Keywords: Computer system, evaluation, accreditation, higher education.

En el contexto del enfrentamiento político y mediático de las últimas elecciones presidenciales de los Estados Unidos de América, esta investigación compara el impacto y alcance de la opinión política de los medios tradicionales de referencia (The New York Times y The Washington Post), frente a dos medios nativos digitales (The Huffington Post y Politico.com), a través del análisis de un total de 162 editoriales y artículos de opinión publicados en sus respectivos espacios digitales y en las redes sociales. El resultado muestra que los medios nativos digitales analizados no amenazan el liderazgo de los medios tradicionales en la red, aunque el impacto y alcance de los editoriales de ambos es bajo y se observa la ausencia de una estrategia y criterio a la hora de posicionarse en la red, donde no consiguen ganar espacio, además de un escaso interés de los lectores online por la opinión política.

El flujo simultáneo de líquido y gas es una de las combinaciones más complejas de flujo bifásico. Para este estudio se seleccionaron como fluidos de trabajo Glicerina en solución con agua al 80 % y Gel industrial. Estos por sus viscosidades permiten establecer los sistemas deseados para el estudio, con valores de Reynolds menor a 15. Fueron desarrollados experimentos para la determinación de las propiedades hidrodinámicas del los fluidos y los parámetros que caracterizan este tipo de flujo en un canal vertical. Fue obtenido a partir del análisis físico matemático de losexperimentos realizados, un modelo teórico experimental capaz de evaluar las fuerzas y coeficientes de arrastre para una burbuja aislada y un tren de burbujas. Se realizaron modelaciones computacionales de los distintos regímenes de trabajo, validadas con los resultados experimentales. Obteniéndose simulaciones y resultados que permiten visualizar y analizar el comportamiento real del sistema.Palabras claves: flujo bifásico, número de Reynolds, burbuja aislada, tren de burbujas, coeficientes de arrastre, fuerzas de arrastre._________________________________________________________________________________AbstractThe study of simultaneous flow of liquid and gas over a conduit is two phases flow combinations more complex that exist. For the study we select fluid (glycerin in solution with water (80 %) and industrial gel) that establish flow models necessary for the investigation the desired systems. And is obtained from physical-mathematical analysis of obtained results made experiment for different configurations, a theorys experimental model have evaluate the drag coefficient and force acting on only bubble and train bubbles in job regimen for Reynolds value less and equal to 15. In the present study was performed computational modeling of different patterns, validated with experimental results.Simulations and results obtained for visualizing and analyzing the actual system behavior. These models are ready for been used for other configurations in future studies.Key words: two phases flow, Reynold´s number, only bubble, train of bubble, drag coefficient, drag forces.

El Aneurisma de Aorta Abdominal es la dilatación localizada, irreversible y progresiva que experimenta la pared aortica. Esta patología ha sido reconocida como un importante problema de salud, puesto que su ruptura está asociada mayormente a consecuencias fatales. La falta de criterios fiables, respecto a los actualmente utilizados, para la evaluación del riesgo de ruptura, constituye un inconveniente en la gestión clínica de la enfermedad. El presente trabajo tiene como objetivo evaluar el riesgo de ruptura de Aneurismas de Aorta Abdominal, mediante indicadores numéricos, como es previsto por el enfoque biomecánico. Fueron utilizadas técnicas de modelación por elementos finitos para determinar el comportamiento del flujo sanguíneo y el estado tensional de la pared arterial. Los resultados mostraron que ninguno de los aneurismas analizados presenta riesgo de ruptura elevado y que la evaluación del riesgo de ruptura mediante índices numéricos, es un camino viable para prever la ruptura de un aneurisma específico.Palabras claves: aneurisma de aorta abdominal, factores biomecánicos, interacción fluido-sólido, riesgo de ruptura.______________________________________________________________________________AbstractAbdominal Aortic Aneurysm is a localized, progressive and permanent dilation of the infra-renal aorta.AAA has increasingly been recognized as an important health problem in the last decades. The AAA rupture is mostly associated with fatal consequences. The lack of more reliable criteria for rupture riskassessing, results in a problem in the clinical management of the disease. This paper aims to assess the rupture risk of abdominal aortic aneurysms by means of numerical indexes, as envisaged by the biomechanical approach. Finite Volume Techniques were used to determine the blood flow behavior within aneurysmatic sac and the structural state of the arterial wall. The results showed that none of the assessed aneurysms is at high rupture risk. The rupture risk assessment by using numerical indices is a viable way to predict the rupture of a specific aneurysm.Key words: abdominal aortic aneurysm, biomechanical factors, fluid-solid interaction, rupture risk.

A new cathode material, FeS2-decorated carbon nanofiber (CNF), is proposed for Li-S batteries. The structure and physicochemical properties of the material have been engineered to enhance the poor cycling stability typically displayed by sulfur composites. The composite material shows a complex architecture with a matrix of CNF hosting the sulfur and core-shell FeS2 nanoparticles acting as a catalyst for a solid phase conversion-type reaction. This cathode delivers high discharge capacities of 864, 798, 689, 595 and 455 mAhg−1 at C/10, C/5, C/2, 1C and 2C, respectively, with a stable capacity retention of 87% at 2C after 300 cycles. FeS2-decorated CNF has been characterised using several techniques, including in-situ battery measurements at the ALBA synchrotron facility and high-throughput microscopy, giving valuable insights into its charge/discharge reaction mechanism. The excellent performance obtained is combined with the use of just low-cost and abundant elements such as iron, sulfur and carbon, which makes this battery highly promising for the next generation of electrochemical energy storage devices. [ABSTRACT FROM AUTHOR]