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Beliefs and Attitudes of Hesitant Spaniards Towards COVID-19 Vaccines: "A Personal Decision"
No full textBackground/Objectives: Vaccine hesitancy has increased during the coronavirus pandemic, a period marked by the spread of disinformation and conspiracy theories about COVID-19 vaccines. This qualitative study aimed to explore the beliefs and attitudes of Spaniards towards COVID-19 vaccines and analyze the role of information sources in this process. Methods: Semi-structured interviews were conducted with 35 residents of Spain who exhibited varying levels of vaccine hesitancy. Through thematic content analysis, the narratives supporting vaccination-related decisions, as well as the influence and trust in information sources, were examined. Results: Reasons for getting vaccinated included perceptions of it being 'almost an obligation' and 'fear of illness and death'. Conversely, reasons for not getting vaccinated included 'uncertainty about vaccines', the belief that 'the risk is not real', and the perception that 'vaccination is a personal decision'. Regarding vaccine-related information sources, interviewees expressed distrust of the media, particularly television, as they considered news about vaccine effectiveness and characteristics to be contradictory and constantly changing, which created uncertainty about its reliability. Most interviewees were unsure if social media influenced their decision not to get vaccinated. However, those who acknowledged its impact mentioned trusting sources such as people with a university education. Additionally, close contacts¿particularly healthcare professionals¿had a significant influence on the decision not to get vaccinated. Conclusions: This study shows that the decision not to vaccinate is shaped by personal beliefs and sources of information¿particularly social media and close acquaintances, including healthcare professionals.The study part of the PredCov project (multi-source and multi-method prediction to support COVID-19 policy decision-making) was financed through the agreement signed between the Community of Madrid (Ministry of Education, Universities and Science) and the Madrid University Carlos III for the direct grant of EUR 4,859,000 which fund the development of research activities on SARS-CoV 2 and COVID-19 disease financed with REACT-EU resources from the European Regional Development Fund “A way of making Europe”. This paper has also received funding from the HEALTHCOM project coordinated by the University Carlos III of Madrid, and financed by the State Research Agency of the Ministry of Science and Innovation for the period 2023–2027, ref: PID2022-142755OB-I00
Clustering time series by extremal dependence
No full textThe goal of this paper is to characterize the temporal dependence structure on the extremes of time series and use such dependency to group them. In particular, three similarity measures to capture extremal dependence are proposed, being their performance assessed in different scenarios. This will involve the use of classical time series clustering algorithms, as well as rigorous evaluation of their performance in both simulated scenarios and real-world time series data sets. The focus will be on comparing the performance of these similarity measures with different clustering methods, and illustrate the efficacy of extremal dependence-based clustering in meteorological data. To achieve this, we will consider a dataset consisting of daily maximum temperatures recorded at 500 stations across Europe.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature
Thermal stress in externally irradiated tubes of solar central receivers with a gas-particle fluidized dense suspension
Get PDFOne of the objectives of the new generation of concentrating solar power plants is to increase the actual temperature limit (565 ◦C) up to or near 1000 ◦C. An alternative heat transfer fluid that could help to reach this objective is the use of a fluidized dense gas–particle suspension ascending through a vertical tube. Since the predominant cause of rupture in solar receivers is the creep-fatigue damage process, which is mostly influenced by the maximum temperatures and stress experienced along the tube, the main objective of this work is to numerically study the thermomechanical behavior of a non-uniform externally irradiated tube where particles are fluidized and moves upwards. The heat transfer problem in the two media present (i.e. dense suspension of particles and tube wall) was solved separately: a Computational Particles Fluid Dynamic model solves the heat transfer in the particles, whereas a three dimensional Finite Volume model simulates the heat conduction through the tube wall to obtain the temperature profile, which serves as input to calculate the thermal stress of the tube with an analytical method. Higher thermal stresses were obtained for an absorbed power of 250 kW/m2 (, = 219 MPa) compared to that for an absorbed power of 500 kW/m2 (, = 72 MPa) due to the lower temperature difference between the front and rear sides of the tube caused by the more pronounced increase of the radiative losses in the front side of the tube compared to that at the rear side. The thermomechanical behavior of a particle receiver was compared to that of a molten salt receiver. For an incident solar flux of 500 kW/m2, the particle receiver reduced the maximum thermal stress by 73% compared to the molten salt receiver. However, the tube’s maximum temperature exceeded the working limit for stainless steel tubes. In order for the receiver to survive heat fluxes characteristic of solar power plants, research into technological solutions that allow to improve the effectiveness of the heat transfer rate from the tube to the particle flow is necessary.This work was partially funded by the project PID2021-127322OB-I00 funded by the Ministerio de Ciencia e Innovación, Spain and by FEDER Una manera de hacer Europa; Project TED2021-131046B-I00 funded by the Ministerio de Ciencia, Innovación y Universidades - Agencia Estatal de Investigación (AEI) Plan de Recuperación, Transformación y Resiliencia-NextGenerationEU, Spain; Project SBPLY/21/180501/000017, funded by the Regional Government of Castilla-La Mancha, Spain and by FEDER Una manera de hacer Europa; Project RED2022-134219-T, funded by the Ministerio de Ciencia, Innovación y Universidades - Agencia Estatal de Investigación (AEI), Spain , Project 2022-GRIN-34343, funded by Universidad de Castilla-La Mancha, Spain , and Project ROTORNEA-CM-UC3M funded by the fellowship Programa de apoyo a la realización de proyectos interdisciplinares de I+D para jóvenes investigadores de la Universidad Carlos III de Madrid 2021–2022 on the frame of Convenio Plurianual Comunidad de Madrid-Universidad Carlos III de Madrid 2019–2022
Low-Voltage Ride-Through Algorithm for Grid-Forming Converters
No full textIn recent years, the increasing integration of renewable energy sources into power systems has led to significant changes in grid operation. Power electronic converters are primarily used to connect these power plants to the electrical system and, as key components in modern power systems, grid-forming (GFM) converters have emerged to provide the ability to autonomously establish and maintain system stability without the need for synchronous generators (SGs). The current contribution during faults is one of the main differences between SGs and power converters, which can affect protective systems. The most recent grid codes require a fast current injection in the event of a fault. This article presents a low-voltage ride-through control strategy for GFM converters based on virtual-flux orientation according to the European Commission Regulation (EU) 2016/631 and the Spanish Technical Supervision Standard requirements. For the validation of this control algorithm, a hardware test bed has been implemented consisting of two dc voltage sources emulating a photovoltaic plant feeding the dc bus of a voltage source converter and, finally, a grid emulator where the different voltage faults have been programmed.This work was supported in part by MCIN/AEI/ 10.13039/501100011033 under Grant PDC2022-133349-I00 and in part by the European Union “NextGenerationEU/PRTR
GEOCONFRONT
Get PDFEl objetivo principal del proyecto es estudiar el papel de la frontera como espacio de conflicto en España y América Latina, seleccionando para ello una serie de casos significativos en un arco temporal comprendido, fundamentalmente, entre 1840 y 2020. El enfoque adoptado en el proyecto se articula sobre dos estrategias teórico-metodológicas principales. En primer lugar, la aplicación de una perspectiva a caballo entre la geografía histórica, la geopolítica y la historia de la geografía y la cartografía. En segundo lugar, el uso de una metodología comparativa, apoyada en el análisis y contraste de diversos casos representativos de conflictos significativos desarrollados en áreas de frontera y asociados directamente a la existencia de la frontera, aunque no necesariamente ligados a procesos de delimitación o demarcación
Accelerated deployment of renewable energy sources as a matter of overriding public interest
No full textEl presente trabajo es el resultado de la adaptación, revisión y actualización de unos epígrafes que forman parte de un trabajo mucho más amplio que, como libro, su autor ha publicado en 2025 en la editorial Dykinson con el título “El sistema administrativo del clima”. El libro se encuentra disponible en open access y puede descargarse de forma completa en: https://hdl.handle.net/10016/45440[ES] La consecución de la tan ansiada neutralidad climática se hace descansar en las posibilidades que ofrece la llamada transición energética. Esta transición energética centra su atención, además de en la reducción de las emisiones de gases de efecto invernadero y en la eficiencia energética, también en el despliegue de energías renovables. La aceleración de proyectos de energías renovables no sólo se está favoreciendo sino que ha llegado a blindarse al considerarse como una cuestión de interés público superior. Un blindaje que precipita su desarrollo y materialización en el territorio por encima de otros intereses socio-económicos e, incluso, ambientales si bien, en última instancia, no puede olvidarse que la transición energética que posibilita estas infraestructuras de energías renovables ha de ser igualmente una transición socialmente justa.[EN] Achieving the longed-for climate neutrality relies on the possibilities offered by the so-called energy transition. This energy transition focuses not only on the reduction of greenhouse gas emissions and energy efficiency, but also on the deployment of renewable energies. The acceleration of renewable energy projects is not only being favoured but has even been shielded as a matter of overriding public interest. A shielding that precipitates their development and materialisation in the territory above other socio-economic and even environmental interests, although, ultimately, it must not be forgotten that the energy transition that makes these renewable energy infrastructures possible must also be a socially just transition
Reprogrammable mechanical metamaterials via passive and active magnetic interactions
No full textThis study experimentally demonstrates the reprogrammability of a rotating-squares-based mechanical metamaterial with an embedded array of permanent magnets. How the orientation, residual magnetization, and stiffness of the magnets influence both the static and dynamic responses of the metamaterial is systematically investigated. It is showed that by carefully tuning the magnet orientation within the metamaterial, notable tunability of the metamaterial response can be achieved across static and dynamic regimes. More complex magnetic node configurations can optimize specific structural responses by decoupling the tunability of quasi-static stress-strain behavior from energy absorption under impact loading. Additionally, reprogrammability can be further enhanced by an external magnetic field, which modulates magnetic interactions within the structure. This work paves the way for developing engineered structural components with adaptable mechanical responses, reprogrammable through either the redistribution of magnetic elements or the application of an external magnetic field.The authors acknowledge support from Ministerio de Ciencia e Innovacion MCIN/AEI/10.13039/501100011033 under Grant number PID2020- 117894GA-I00, the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No. 947723, project: 4D-BIOMAP), and the Catedra UC3M–NAVANTIA– MONODON: DEEPTECH. G.R. acknowledges the Swiss National Science Foundation for funding the project. Project: Metamaterials with reprogrammable shape and stiffness (grant no.: 217901)
Ubicar la indignación: reflexiones y escenarios de acción
No full textLa indignación no es simplemente ira o rabia individual, sino una experiencia que requiere consciencia social y un horizonte compartido. Cuando nos indignamos, estamos expresando nuestra concepción de cómo debería ser el mundo, ubicando las injusticias en un orden común donde reconocemos qué es lo justo. Este libro explora precisamente esa dimensión social de la indignación como brújula moral que orienta la construcción de sociedades más justas. Recopilando estudios de investigadores internacionales, la obra se organiza en dos bloques: "Reflexiones", que analiza cómo se constituye la indignación, su concepto y función social; y "Escenarios de indignación", que examina su presencia en nuestro contexto cultural. Con este recorrido, la obra busca desarrollar una topología del orden social que nos ayude a comprender mejor cómo habitamos el mundo común y cómo podemos enfrentar juntos los desafíos que compartimos. Así, ofrece un espacio de reflexión para indignaciones pasadas, presentes y futuras.BLOQUE I: Reflexiones. -- La significación filosófica de la indignación en el pensamiento de Aristóteles / Ignacio García Peña (pp. 15-34). -- Indignación y política republicana en Maquiavelo / Guido Frilli (pp. 35-48). -- El grito indignado de los Calas: Voltaire y la justicia del corazón / Marco Menin (pp. 49-62). -- Ira, indignación y política: un enfoque cognitivo / Giulio Sacco (pp. 63-76). -- Indignación y agotamiento vis-à-vis: si el agotado agota, ¿también el indignado “indigna”? Indignarse ante la vida (indignación ontológica) / Marina Christodoulou (pp. 77-94). -- Perdón y Ética de la Indignación: Un Ensayo / M. Hadi Fazeli (pp. 95-106). -- El cuerpo en duelo de “la izquierda”: un acercamiento al paradigma actual de los movimientos sociales autónomos / Andrea Acosta Landín (pp. 107-120). -- Más allá de la inmovilidad: ¿por qué la indignación no conduce a la acción? / Grégori de Souza (pp. 121-132). -- Crisis ambiental y cultura: una ecosofía de la indignación / Luca Valera (pp. 133-146). -- BLOQUE II: Escenarios de indignación. -- ¡Contra el cambio! Platón sobre el conservadurismo egipcio y la posibilidad de innovación en las artes / Tomás N. Castro (pp. 149-162). -- La indignación como anagnórisis y catarsis en el Λόγος σωκρατικός / Álvaro R. Maestro Ibarzábal (pp. 163-176). -- Escribir la indignación. Literatura y crítica ético-política en Isabelle de Charrière / Francesco Boccolari (pp. 177-190). -- Wollstonecraft y el poder movilizador de la indignación / Alexandra Abranches (pp. 191-202). -- Experiencia y mutismo: sobre la indignación en Walter Benjamin y Simone Weil / César Adolfo Arceo-Arévalo (pp. 203-216). -- El desafío de Hayek para una filosofía de la indignación / Diego Colomés (pp. 217-230). -- Capitalismo e indignación social. Una reconfiguración emancipatoria desde Nancy Fraser / Jorge Ojeda-Cabrera (pp. 231-242). -- El eco de la catástrofe. Basinski, Deleuze y la resistencia sonora del arte / Sofía Cortez-Maciel (pp. 243-256). -- Vergüenza e indignación en el horizonte del nihilismo contemporáneo / Dune Valle Jiménez (pp. 257-270). -- Valencias de la indignación / Guillermo García Santos (pp. 271-284). -- Estética do lixo: el cine frente a realidades insoportables / Ananda Cinti-Romero (pp. 285-298). -- Acampe: la resistencia del arraigo en clave vegetal / Claudia Donoso (pp. 299-308)
Unraveling the aging-reversal potency of stem cell-derived extracellular vesicles in a rat model of premature cardiac senescence
No full textCardiosphere-derived cells (CDCs) and their extracellular vesicles (CDC-EVs) can rejuvenate and improve cardiac function, but their efficacy varies among donors. This study aimed to identify predictors of CDC-EV potency. CDCs from human donors were analyzed for phenotypical and biological properties. The anti- aging activity of CDC-EVs was tested using an in vitro matrix assay. Results showed that donor age did not determine potency, but CDC senescence correlated with most bioactive properties. However, senescence alone was insufficient to predict CDC-EV potency. CDC-EVs were classified as more potent (P-EVs) or less potent (NP-EVs) based on assay performance. In a rat model of premature cardiac aging, P-EVs reduced senescence-associated GLB1 gene expression and protected against hypertrophy and fibrosis,
while NP-EVs had negative effects. The study concludes that CDC-EV anti-aging potency cannot be predicted by donor age or CDC senescence, proposing an in vitro potency assay for evaluating CDC-EVs before clinical use
The role of ply clustering in the impact damage of woven carbon/epoxy laminates: An experimental-numerical study
No full textThis study investigates the impact behaviour of carbon/epoxy woven laminates through experimental and numerical analysis, with particular emphasis on the effects of ply clustering. Drop weight tower tests were performed for three different ply clustering configurations. In addition, 3D Digital Image Correlation (DIC) techniques were used to analyse out-of-plane displacements, providing a deeper insight into the phenomenon that triggers the failure mechanisms. Internal damage was further characterized using ultrasonic C-scan techniques to quantify the extent of damage. A major contribution of this work is the development of a three-dimensional constitutive model based on continuum damage mechanics that incorporates multiple failure mechanisms, with special attention to transverse shear damage. Numerical simulations of the drop-weight tower tests were performed for all three laminate configurations, validating the ability of the constitutive model to predict force and energy responses, as well as the failure mechanisms observed during the tests. The constitutive model was found to be useful in understanding the interaction between interlaminar and intralaminar failure mechanisms under out-of-plane loading conditions, such as drop weight tower tests and other impact scenarios. The study highlights the importance of laminate clustering for perforation resistance and the need to incorporate transverse shear damage into numerical models to accurately capture the perforation process.This work has received funding from the Vicerrectorado de Política Científica project from the University Carlos III of Madrid, Spain : 2023/00264/001, 2020/00123/001 and 2014/00006/003