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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.