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Efficient CeO2 and CeO2-Al2O3 supports for Ru as 3rd generation ammonia synthesis catalysts: enhanced kinetic mechanism over commercial Ru/CeO2
No full textIn order to make the ammonia synthesis process more sustainable and facilitate its coupling with renewable energies, it is first imperative to carry out this reaction at lower temperatures, which requires new catalysts showing high activity (i.e., low activation energies) and proper kinetic characteristics (e.g., resistance to H2 and NHx poisoning) while operating at these temperature conditions. While Ru presents high activity in this reaction, it suffers from strong hydrogen inhibition, which is particularly important at low temperatures. The use of promoters such as cerium oxide can mitigate this issue taking advantage of metal-support interactions generated upon reduction treatments (e.g., electron donation and the formation of new oxygen vacancy sites). However, lab-synthesized ceria materials usually present low surface areas, thereby limiting the generation of oxygen vacancies and the ammonia synthesis activity as a result of weak metal-support interactions. With the aim to overcome this issue, we prepared, by a simple impregnation method, high surface area ceria- and ceria-alumina-supported Ru catalysts with improved ammonia synthesis performance at moderate temperatures. In this sense, lab-synthesized Ru/CeO2 (with higher specific surface area and lower crystallinity than commercial ceria) showed stronger metal-support interactions than the commercial sample, which resulted in a superior global ammonia synthesis kinetic mechanism with more positive hydrogen reaction orders (i.e., more resistant to hydrogen inhibition) and significantly lower activation energies (46 vs 61 kJ mol-1). We found that the use of alumina as structural support increased the surface area of ceria, thereby promoting the Ru-CeO2 interaction and the catalytic performance. We analyzed the effect of the surface chemistry of two different commercial aluminas (acid and basic) with similar surface areas. Basic alumina was found to increase the specific surface area of the catalyst to a larger extent as compared to acid alumina. Thus, the Ru/CeO2-Al2O3 catalyst with a 50 wt% of basic alumina showed an ammonia synthesis activity of 1.9 mmol g h -1 at 400 °C and ambient pressure and an activation energy as low as 44.8 kJ mol-1.This publication is part of the project BioEnH2, funded by MCIN /AEI /10.13039/501100011033
Design and catalytic application of Ag–Au nanoprisms: enhancing A3 coupling efficiency with minimal gold concentration
No full textA novel bimetallic Ag-Au nanoprism incorporating trace levels of gold (ppm range) was synthesized via a wet-chemical method. The material was comprehensively characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM) mapping, X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). This new nanostructure exhibits a remarkable synergistic interaction between the silver nanoprism and meager amounts of gold, resulting in highly efficient catalytic activity for the A3 coupling reaction involving aldehydes, alkynes, and amines. The reaction proceeds efficiently in water at 60 ℃, accommodating a broad substrate scope and showcasing its versatility. Notably, the catalytic system achieves excellent performance even at ultralow gold loadings (80 ppm), highlighting its cost-effectiveness and sustainability. Furthermore, the catalyst demonstrates robust reusability, retaining its activity over four consecutive cycles in aqueous media.The authors are grateful to the IASBS Research Council and Alicante University for their support of this work. This work is based upon research funded by Iran National Science Foundation (INSF) under the project no. 4024819. The authors also would like to thank the Ministerio de Ciencia, Innovación y Universidades (RED2018-102387-T, PID2019-107268GB-100), and Generalitat Valenciana (IDIFEDER/2021/013) for support of this work
La no limitación del derecho a la deducción del IVA en aras a garantizar el principio de neutralidad: la STJUE de 4 de octubre de 2024, C-475/23
No full textEsta sentencia profundiza en la interpretación del art. 168.a) de la Directiva IVA de forma que el derecho a la deducción no se vea denegado por el incumplimiento de ciertos requisitos formales ni cuando exista una relación directa e inmediata entre una operación por la que se soporta IVA y otra operación por la que se repercute IVA. Con este pronunciamiento, el TJUE refuerza el principio de neutralidad en el IVA.This judgment elaborates on the interpretation given by the Court of Justice of the European Union to Article 168.a) of the VAT Directive. Accordingly, the right to deduct cannot be denied when some formal requirements are not met nor when there is a direct and immediate relationship between an operation for which VAT is input and another operation for which VAT is charged. With this judgment, the CJEU reinforces the principle of neutrality in VAT
Executive Functioning in secondary education students: differential analysis by gender and grade
No full textLas funciones ejecutivas (FE) son un conjunto de habilidades cognitivas esenciales que permiten a las personas autorregular su comportamiento y alcanzar objetivos de manera eficaz. A pesar de que se trata de un fenómeno que lleva tiempo siendo objeto de estudio, son pocos los artículos que analizan las diferencias de género a lo largo de las diversas etapas académicas. Es por ello que el objetivo de este estudio fue estudiar el FE de estudiantes de Educación Secundaria Obligatoria y 1º de Bachillerato (12-17 años) y analizar sus diferencias en los diferentes cursos y en función del sexo. Se evaluó a 1164 adolescentes españoles (559 varones y 599 mujeres) de 12 a 17 años utilizando el Cuestionario de funcionamiento ejecutivo para adolescentes y adultos (ADEXI). Los análisis revelaron diferencias estadísticamente significativas en las FE por sexo, siendo las mujeres quienes obtuvieron más dificultades en todas las subescalas evaluadas (Control inhibitorio y Memoria de trabajo) y en la puntuación total. Además, se observó una mejora en las FE con la edad, mostrando los estudiantes de cursos superiores un mejor desempeño. Comprender las diferencias en el FE en diferentes edades y en función del sexo conlleva una importante implicación práctica. La población infanto-juvenil no solo podría beneficiarse de estos hallazgos en el ámbito académico, donde la metodología de trabajo podría adaptarse en función de las necesidades, sino que también es una herramienta útil en la práctica clínica, especialmente en poblaciones con trastornos del neurodesarrollo.Executive functions (EF) are a set of essential cognitive skills that allow people to self-regulate their behavior and achieve goals effectively. Although this phenomenon has long been studied, there are few articles that analyze gender differences across academic stages Therefore, the aim of this study was to examine EF of students in Compulsory Secondary Education and 1st year of High School (ages 12 - 17 years) and to analyze differences based on grade level and gender. A total of 1,164 Spanish adolescents (559 males) aged 12-17 years were assessed using the Adolescent and Adult Executive Functioning Questionnaire (ADEXI). Analyses revealed statistically significant differences in EF by gender, with females obtaining more difficulties in all subscales evaluated (Inhibitory control and Working memory) and the total score. In addition, an improvement in EF with age was observed, with students in higher grades showing better performance. Understanding differences in EF across different ages and genders has important practical implications. The child and adolescent population could benefit from these findings not only in the academic field, where teaching methods could be adapted to meet specific needs, but also as a useful tool in clinical practice, especially in populations with neurodevelopmental disorders.Esta investigación fue financiada por el Ministerio de Ciencia e Innovación, la Agencia y del Fondo Europeo de Desarrollo Regional (Proyecto PID123118NA-100 financiado por MCIN /AEI /10.13039/501100011033 / FEDER, UE
Automatic annotation of protected attributes to support fairness optimization
No full textRecent research has shown that the unaware automation of high-risk decision-making tasks can result in unfair decisions being made. The most common approaches to address this problem adopt definitions of fairness based on protected attributes. Precise annotation of protected attributes enables the application of bias mitigation techniques to commonly unlabeled kinds of data (e.g., images, text, etc.). This paper proposes a framework to automatically annotate protected attributes in data collections. The framework focuses on providing a single interface to annotate protected attributes of different types (e.g., gender, race, etc.) and from different kinds of data. Internally, the framework coordinates multiple sensors to produce the final annotation. Several sensors for textual data are proposed. An optimization search technique is designed to tune the framework to specific domains. Additionally, a small dataset of movie reviews —annotated with gender and sentiment— was created. The evaluation in datasets of texts from diverse domains shows the quality of the annotations and their effectiveness to be used as a proxy to estimate fairness in datasets and machine learning models. The source code is available online for the research community.This research has been partially funded by the University of Alicante and the University of Havana, the Spanish Ministry of Science and Innovation, the Generalitat Valenciana, and the European Regional Development Fund (ERDF) through the following funding: At the national level, the following projects were granted: TRIVIAL (PID2021-122263OB-C22); CORTEX (PID2021-123956OB-I00); CLEARTEXT (TED2021-130707B-I00); and SOCIALTRUST (PDC2022-133146-C22), funded by MCIN/AEI/10.13039/501100011033 and, as appropriate, by ERDF A way of making Europe, by the European Union or by the European Union NextGenerationEU/PRTR. Also, the VIVES: “Pla de Tecnologies de la Llengua per al valencià” project (2022/TL22/00215334) from the Projecte Estratègic per a la Recuperació i Transformació Econòmica (PERTE). At regional level, the Generalitat Valenciana (Conselleria d'Educacio, Investigacio, Cultura i Esport), granted funding for NL4DISMIS (CIPROM/2021/21). Moreover, it was backed by the work of two COST Actions: CA19134 - “Distributed Knowledge Graphs” and CA19142 - “Leading Platform for European Citizens, Industries, Academia, and Policymakers in Media Accessibility”
Microplastics in rocky shore mollusks of different feeding habits: An assessment of sentinel performance
No full textMicroplastics (MPs) accumulation in rocky shore organisms has limited knowledge. This study investigated MPs accumulation in filter-feeding oysters, herbivorous limpets and carnivorous snails to assess their performance as sentinel species in the MPs trophic transfer. The samples were obtained along a contamination gradient in the Santos Estuarine System, Brazil. All three studied species showed MPs concentrations related to the contamination gradient, being the oysters the species that showed the highest levels, followed by limpets and snails (average of less and most contaminated sites of 1.06–8.90, 2.28–5.69 and 0.44–2.10 MP g−1, respectively), suggesting that MPs ingestion rates are linked to feeding habits. MPs were mainly polystyrene and polyacetal. The polymer types did not vary among sites nor species. Despite minor differences in percentages and diversity of size, shape, and color classes, the analyzed species were equally able to demonstrate dominance of small, fiber, transparent, black and blue MPs. Thus, oysters, limpets, and snails are proposed as sentinels of MPs in monitoring assessments.This research was supported by the São Paulo Research Foundation (FAPESP n. 2022/14011-3). I.B. Castro (PQ 304398/2021-7) was recipient of research productivity fellowship from the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). V.V. Ribeiro (FAPESP n. 2022/08669-6) and T.M.A. Soares (FAPESP n. 2023/05277-2) were sponsored by São Paulo Research Foundation
Victimization and aggression in intimate partner violence relationships: A systematic review from the attachment perspective
No full textLa violencia en pareja es un fenómeno complejo y multidimensional influenciado por diversos factores, como el vínculo de apego que se forma con las figuras de protección en las etapas tempranas de la vida, con efectos a largo plazo. Esta investigación busca determinar la conexión entre el estilo de apego y el rol de agresor o víctima en dinámicas de violencia de pareja. Se realizó una revisión sistemática siguiendo la guía PRISMA, consultando las bases de datos Web of Science y Scopus, lo que permitió seleccionar 203 artículos según criterios establecidos. Los resultados vinculan la inseguridad en el estilo de apego con la perpetración y victimización de violencia, destacando la importancia de reconocer cómo los estilos de apego pueden actuar como factor protector o de riesgo para prevenir la violencia en pareja.Partner violence is a complex and multidimensional phenomenon influenced by various factors, such as the attachment bond formed with primary caregivers during early life stages, with long-term effects. This research aims to determine the connection between attachment style and the role of aggressor or victim in partner violence dynamics. The systematic review was conducted following the PRISMA guidelines, using Web of Science and Scopus databases, which resulted in the the selection of 203 articles based on predefined criteria. The results link attachment insecurity to both the perpetration and victimization of violence, highlighting the importance of recognizing how attachment styles can act as either a protective or risk factor in the prevention of partner violence
Franco’s persecution of religious minorities. The unusual case of the Protestants of Medina del Campo (1948-1962)
No full textEl aislamiento del régimen franquista después de la Segunda Guerra Mundial y la presión diplomática de países como Inglaterra y Estados Unidos ante la persecución de los protestantes en España influyeron en la aprobación del Fuero de los Españoles, que en su artículo 6 establecía una tolerancia limitada para las confesiones no católicas. Gracias a ello pudieron reabrirse numerosas capillas protestantes en todo el país y retomar los cultos, siempre que se celebrasen en privado y bajo estrecha vigilancia de las autoridades. En este contexto, el caso de la Iglesia Evangélica de Medina del Campo, en la provincia de Valladolid, tiene una especial relevancia debido a la dureza y persistencia de la acción represiva que sufrió durante los años 40 y 50. A través del análisis de fuentes documentales inéditas procedentes de varios archivos y de testimonios orales, podemos concluir que la confluencia de los dos poderes implicados, civil y eclesiástico, en su versión más fanática e intolerante, provocó una reacción nacional e internacional inédita en otras provincias españolas. Esto hizo que el caso de la Iglesia Evangélica de Medina del Campo pasara a la historia como paradigma de la represión extrema a la que fueron sometidas las minorías religiosas en España durante el franquismo.The isolation of Franco’s regime after the Second World War and diplomatic pressure from countries such as England and the United States in the face of the persecution of Protestants in Spain influenced the approval of the Fuero de los Españoles, article 6 of which established limited tolerance for non-Catholic denominations. This allowed the reopening of numerous Protestant chapels throughout the country and the resumption of worship, as long as it was held in private and under close supervision of the authorities. In this context, the case of the Evangelical Church of Medina del Campo, in the province of Valladolid, is particularly relevant due to the harshness and persistence of the repressive action it suffered during the 1940s and 1950s. Through the analysis of unpublished documentary sources from various archives and oral testimonies, we can conclude that the confluence of the two powers involved, civil and ecclesiastical, in their most fanatical and intolerant version, provoked a national and international reaction unheard of in other Spanish provinces. This meant that the case of the Evangelical Church of Medina del Campo went down in history as a paradigm of the extreme repression to which religious minorities were subjected in Spain during Franco’s regime
Educational Technology and E-Learning as Pillars for Sustainable Education
No full textThe rapid advancements in Educational Technology (EdTech) and e-learning necessitate a critical focus on the principles of sustainability to ensure compliance with and the achievement of Sustainable Development Goal 4 (SDG 4), quality and lifelong education, conceived by the United Nations (UN). This closing editorial, for the Special Issue entitled “Sustainable E-Learning and Educational Technology”, addresses the significant gap in knowledge between the adoption of technology and its long-term impact in terms of sustainability. The six articles included in this Special Issue present empirical evidence across three main thematic areas: (1) measurement and fostering of sustainable lifelong learning competencies (e.g., self-regulated learning using learning analytics in flipped classrooms); (2) validation of quality and inclusion frameworks (e.g., self-assessment guides for accessible virtual education); and (3) successful application of educational software (such as Scratch) to meet specific pedagogical objectives aligned with SDG 4. In terms of future directions, priority research areas include leveraging artificial intelligence (AI) and green information and communication technologies (ICT) for environmentally and pedagogically sound personalization, conducting longitudinal ethical studies on learning analytics data, and developing sustainable design models for accessible open educational resources (OERs). We aim for this Special Issue to serve as a valuable resource, urging researchers to integrate the principles of equity, accessibility, and long-term viability into future EdTech development
Computational Thinking in the Latin American Child Population: an Analysis of the BCTt Test
No full textEn este trabajo se explora la prueba Beginners Computational Thinking Test en una muestra formada por 116 infantes mexicanos y colombianos. Para ello, se revisaron diversos conceptos del Pensamiento Computacional (PC) que dieron origen a esta prueba. Los resultados se analizaron de forma cualitativa con base en las respuestas de los estudiantes participantes en el estudio. Se encontraron inconsistencias entre las instrucciones de los reactivos y las opciones de respuesta emitidas. Los infantes realizan la lectura de las opciones de respuesta de izquierda a derecha como se les ha enseñado el sistema de lectura occidental, lo que dificulta la lectura de las opciones de respuesta que están colocadas en columnas y deben leerse primero de arriba hacia abajo para poder pasar a la siguiente opción de respuesta. Los estudiantes brindaron diferentes respuestas correctas, identificativo de la comprensión parcial del instrumento utilizado. La discusión versa en términos de si la prueba es óptima para evaluar el PC en infantes de cinco años como lo postulan sus autores. Las conclusiones de esta investigación señalan que los estudiantes de cinco años necesitan lenguajes de programación diseñados específicamente para ellos, sencillos, que admitan múltiples combinaciones, tengan sintaxis y gramática, ofrezcan múltiples formas de resolver problemas y sean de su interés. Se dejan de lado los aspectos creativos y autoexpresivos de la programación, que se alinean más estrechamente con la alfabetización, como contar una historia, transmitir ideas y expresar la creatividad.This study explores the Beginners Computational Thinking Test in a sample of 116 Mexican and Colombian children. To this end, various concepts of Computational Thinking (CT) that gave rise to this test were reviewed. The results were analysed qualitatively based on the responses of the students participating in the study. Inconsistencies were found between the instructions for the questions and the answer options provided. The children read the answer options from left to right, as they have been taught in the Western reading system, which makes it difficult to read the answer options that are placed in columns and must be read from top to bottom in order to move on to the next answer option. The students provided different correct answers, indicating partial understanding of the instrument used. The discussion focuses on whether the test is optimal for assessing CP in five-year-old children, as postulated by its authors. The conclusions of this research indicate that five-year-old students need programming languages designed specifically for them, which are simple, allow for multiple combinations, have syntax and grammar, offer multiple ways to solve problems, and are of interest to them. The creative and self-expressive aspects of programming, which align more closely with literacy, such as storytelling, conveying ideas, and expressing creativity, are left out