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Quercetin-doped sol–gel coatings on titanium implants: a promising approach for enhanced immune response and cell adhesion
No full textQuercetin (QUE), a natural flavonoid found in various fruits and vegetables, has diverse biological functions, including anti-inflammatory effects, regulation of cell adhesion and oxidative stress mitigation. In this study, sol–gel materials with increasing concentrations of quercetin (0.5, 1 and 2 wt%) were synthesised and applied onto titanium (Ti) surfaces as coatings. The materials were characterised physiochemically, and in vitro responses were examined using HOb osteoblastic cells and THP-1 macrophages. Human serum protein adsorption was evaluated using nLC-MS/MS. The incorporation of quercetin did not affect the sol–gel network cross-linking, and a controlled release of quercetin was achieved. The materials exhibited no cytotoxicity at any concentration. The HOb cells cultured on quercetin-doped materials were more elongated than those grown on QUE-free coatings, with protruding lamellipodia and increased cell surface. QUE-doped surfaces enhanced the expression of BMP-2, RANKL, and cell adhesion-related genes CTNNB1 and β-actin. In the THP-1 cells, pro-inflammatory gene expression (IL-1β, MCP-1 and iNOS) was down-regulated on 0.5QUE material, while it increased on 2QUE, as did the cytokine liberation. These changes correlated with altered protein adsorption patterns. The 2QUE coatings enhanced the adsorption of acute-phase proteins (SAA1, SAA2 and SAA4), indicating an inflammatory response; this behaviour was not seen on 0.5QUE. Moreover, cell adhesion (COF1, PROF1) and oxidative stress proteins (GPX3, SEPP1, AMBP) were preferentially adsorbed onto QUE-doped coatings. These results highlight the significance of optimising quercetin concentration in sol–gel coatings to modulate the immune response and enhance cell adhesion effectively
Modelización avanzada y efectos de interacción vehículo—vía—estructura para el análisis del comportamiento dinámico de puentes de FFCC en vía convencional y de alta velocidad
No full textCompendi d'articlesEn los próximos 25 años se prevé un crecimiento considerable de la Red Transeuropea de Transporte, pudiendo verse comprometida la seguridad del tráfico. Para asegurar la integridad estructural de las infraestructuras existentes, la Agencia Ferroviaria Europea ha advertido que resulta necesario mejorar los métodos de predicción actuales. Con el foco puesto en los puentes de vigas isostáticos de luces medias—cortas, estructuras propensas a sufrir elevados niveles de aceleración vertical en sus tableros, la presente Tesis Doctoral se centra en el análisis de éstos empleando modelos detallados y tratando de identificar situaciones donde los modelos planos de viga pueden no resultar conservadores a la hora de predecir la máxima respuesta. Además, se evalúa el grado de ajuste alcanzado al considerar el fenómeno de interacción vehículo—vía balasto—estructura en presencia de irregularidades del carril, para mejorar la predicción dinámica en el tablero en condiciones de resonancia y no resonancia.The Trans—European Transport Network is expected to experience significant growth over the next 25 years, which could compromise traffic safety. To ensure the structural integrity of existing infrastructures, the European Union Agency for Railways has highlighted the need to enhance current prediction methods. Focusing on simply supported railway girder bridges of short—to—medium span lengths, which are prone to suffer high vertical acceleration levels, this Doctoral Thesis centres on the analysis of the aforementioned structures using detailed models, trying to identify situations where simplified planar beam assumptions may not be conservative for predicting the maximum response. Furthermore, the degree of adjustment achieved considering the train—track—bridge interaction phenomenon accounting for the vertical irregularities of the rails is evaluated, in order to improve the dynamic predictions under resonant and non—resonant conditions.Programa de Doctorat en Tecnologies Industrials i Material
Gestión sostenible de Recursos Humanos. Aplicación de la sostenibilidad social, ambiental y económica desde una perspectiva interdisciplinar
No full textSe hace necesario entender cómo y porqué las organizaciones pueden y deben aplicar la gestión sostenible de RRHH. En este sentido, este libro se hace eco de las necesidades y desafíos que pueden existir en la aplicación de la gestión sostenible y proporciona una guía para abordar estas complejidades
Porn[Time]: study of cognitive processes related to problematic pornography use
No full textCompendi d'articles, Doctorat internacionalCurrently, pornography consumption is one of the most prevalent online activities, increasing scientific interest in understanding its effects. In particular, the possibility of developing a pattern of abusive consumption, i.e., problematic pornography use (PPU), is one of the main concern. Therefore, in recent years, part of the literature has focused on the study of the mechanisms and factors involved in the onset and maintenance of PPU. However, evidence remains scarce, especially regarding the involvement of cognitive processes. This doctoral thesis aims to shed light on this issue by studying the involvement and etiological role of attentional inhibitory control, time perception processes, and subjective sexual arousal in PPU and other online problematic behaviors: gaming disorder and problematic binge-watching. Some of the main findings question the theoretical premises that place cognitive and executive processes as central etiopathological factors in problematic online behavior.Programa de Doctorat en Psicologi
Reformulating polarized radiative transfer for astrophysical applications (I). A formalism allowing non-local Magnus solutions
No full textThe solar atmosphere is diagnosed by solving the polarized radiative transfer problem for plasmas in Non-Local Thermodynamical Equilibrium (NLTE). A key challenge in multidimensional NLTE diagnosis is to integrate the radiative transfer equation (RTE) efficiently, but current methods are local, limited to constant propagation matrices. The formalism presented in this paper lays the foundations to achieve an efficient non-local integration of the RTE based on the Magnus expansion. Our approach starts formulating the problem in terms of rotations represented in the Lorentz-Poincare group (Stokes formalism) and motivating the use of the Magnus expansion. Then, we combine a highly detailed algebraic characterization of the propagation matrix with Magnus to reformulate the homogenous solution to the RTE. Thus, we obtain a compact analytical evolution operator supporting arbitrary variations of the propagation matrix to first and second order in the Magnus expansion and showing the way to higher orders. Finally, we reformulate the inhomogeneous part to make it solvable with the Magnus expansion too, which gives rise to an interesting new object: the inhomogeneous evolution operator. This provides the first consistent and general formal solution of the RTE that furthermore is non-local, efficient, and accurate by design, with other peculiarity: it separates the integration part from the algebraic formal solution. Our framework is verified analytically and with a computational implementation that leads to a new family of numerical radiative transfer methods and suggests several applications, e.g. accelerating NLTE calculations with non-local radiative transfer. With cosmetic changes, our results apply to other universal physical problems sharing the Lorentz-Poincare algebra of the RTE and special relativity
Acceso a la justicia de personas vulnerables y acciones colectivas: una combinación posible?
No full textEste capítulo1 analiza, brevemente, la posibilidad de hacer uso de lasacciones colectivas como un mecanismo para facilitar y mejorar el acceso a la Justicia delos grupos vulnerables. A tal fin, se estudia la regulación de dicho mecanismo por laDirectiva 2020/1828 del Parlamento Europeo y del Consejo de 25 de noviembre de 2020,relativa a las acciones de representación para la protección de los intereses colectivos delos consumidores, y si su opción por las acciones de representación es adecuada a talpropósito.This chapter analyzes briefly whether class actions can be a mechanism tofacilitate and improve access to justice for vulnerable groups. For this aim, it analyzes theregulation of such mechanisms by Directive 2020/1828 of the European Parliament andof the Council of November 25, 2020 and whether the option of the same for therepresentative action is adequate for this purpose
Educar para transformar conflictos. Valoración de los conocimientos, habilidades y recursos para hacer las paces en la formación de grado en psicología social en Venezuela
No full textEsta investigación analiza el currículo formativo en psicología social impartido en el Grado en Psicología de la Universidad Central de Venezuela usando el marco analítico de la Educación Crítica para la Paz (ECpP). Para ello, establece un conjunto de conocimientos, habilidades y recursos para hacer las paces con la literatura especializada y realiza un estudio de casos intrínseco de corte cualitativo. Se conformó un corpus informativo constituido por 20 programas de asignaturas dictadas por el Departamento de Psicología Social de la Escuela de Psicología de la UCV y se entrevistó en profundidad a 23 estudiantes del Ciclo Aplicado de Psicología Social de las cohortes que comenzaron dicho ciclo entre 2015 y 2018. Los programas analizados presentan amplias referencias interdisciplinares y oportunidades de mejora en la sinergia pedagógica. El reporte del estudiantado señala la promoción de un habitus socio-reflexivo y crítico como recurso principal para la construcción de paz en Venezuela.This research analyses the curriculum of social psychology taught in the undergraduate Psychology program at the Universidad Central de Venezuela, using the analytical framework of Critical Peace Education (CPE). To do so, it establishes a set of knowledge, skills, and resources for making peace based on specialized literature and conducts an intrinsic case study with a qualitative approach. The information corpus was composed of 20 course syllabi from the Department of Social Psychology at the UCV School of Psychology, and in-depth interviews were conducted with 23 students from the Applied Cycle of Social Psychology who began the cycle between 2015 and 2018. The analysed syllabi present broad interdisciplinary references and opportunities for improvement in pedagogical synergy. The students' report highlights the promotion of a socio-reflective and critical habitus as the main resource for peacebuilding in Venezuela.Programa de Doctorat en Estudis Internacionals de Pau, Conflictes i Desenvolupamen
Sustainability in spanish energy companies. A proposal for indicators beyond taxonomy
No full textEste estudio analiza la sostenibilidad de las principales energéticas del IBEX 35: Acciona, Endesa e Iberdrola. Mediante un análisis cualitativo de los Estados de Información No Financiera de 2023, se examina su compromiso con la sostenibilidad, más allá del Reglamento de Taxonomía Ambiental localizando nuevos indicadores. Se concluye que los principales predictores son: Plan de Acción o Estrategia a largo plazo; actividades alineadas con los Objetivos de Desarrollo Sostenible; Doble Materialidad; políticas y análisis de factores medioambientales, sociales y de gobernanza; reporte de información sobre la financiación sostenible de la compañía y certificados que verifican la información reportada.This study analyzes the sustainability of the main energy companies in the IBEX 35: Acciona, Endesa, and Iberdrola. Through a qualitative analysis of the 2023 Non-Financial Information Statements, their commitment to sustainability is examined beyond the local Environmental Taxonomy Regulation by identifying new indicators. It is concluded that the main predictors are: a Long-term Action Plan or Strategy; activities aligned with the Sustainable Development Goals; Double Materiality; policies and analysis of environmental, social, and governance factors; reporting information on the company's sustainable financing; and certificates that verify the reported information
Biochar for Electrochemical Sulfanilamide Detection: Comparative Evaluation of Carbon Paste and Screen-Printed Electrodes
No full textAntibiotics such as sulfanilamide (SFD) pose significant environmental and health risks due to their persistence in wastewater and their potential to contaminate food. However, conventional detection methods for these compounds are often costly and time-consuming. This study proposes activated biochar derived from sugar cane bagasse as a sustainable modifier for electrochemical sensors to detect SFD using adsorptive stripping voltammetry (AdSV). The biochar was functionalized with HNO3 (termed BCA) to enhance SFD preconcentration and was incorporated into two electrode platforms: carbon paste electrodes (CPEs) and screen-printed carbon electrodes (SPCEs). The preparation of each modified electrode (CPME-BCA and SPCE-BCA) was optimized to evaluate its analytical performance. Both BCA-modified electrodes exhibited significantly enhanced SFD oxidation signals compared to those of their unmodified counterparts. The optimized SPCE-BCA demonstrated a linear detection range from 5.0 × 10–9 to 5.0 × 10–6 mol L–1, a limit of detection of 1.5 × 10–9 mol L–1, and high reproducibility, with an RSD of 4.92%. The sensor was successfully applied to spiked samples of tap water, synthetic urine, and low-fat milk, achieving recoveries of between 90.7 and 111%. This work highlights sugar cane bagasse-derived biochar as a cost-effective and eco-friendly material for electrochemical sensing. Notably, SPCE-BCA required less biochar for modification than CPME-BCA, offering a scalable solution for SFD monitoring in diverse matrices.The authors are grateful for the financial support of the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, financial code 001), the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, grants: 303609/2025-7, 150314/2024-8, 444850/2023-6, 308617/2023-1, 311290/2020-5, and 402195/2020-5), and Fundação Araucária (PBA2022011000056 and PDT2020221000003). Financial support from the Brazilian Institute of Science and Technology: INCT-Nanocarbon and INCT-Nanomaterials for Life (Process: 406079/2022-6) is also acknowledged
Experiencias adversas en la infancia y su relación con el bienestar en jóvenes adultos: salud física y mental
No full textCompendi d'articlesLa presente tesis examina el impacto de las Experiencias Adversas en la Infancia (ACEs) sobre la salud física y mental durante la adultez emergente, considerando variables culturales y contextuales específicas de España y Latinoamérica. El Estudio 1 se centró en una muestra de jóvenes españoles, abordando el impacto de las ACEs sobre la salud física, un aspecto poco explorado en esta etapa vital. El Estudio 2 analizó la relación entre las ACEs, las estrategias de afrontamiento y la manifestación de rasgos psicopáticos y altruistas. Este estudio incorpora un enfoque innovador al considerar combinaciones específicas de ACEs en lugar de analizarlas de forma aislada. El Estudio 3 se desarrolló con una muestra de jóvenes latinoamericanos, ampliando el análisis hacia ACEs expandidas, que incluyen factores económicos y sociales relevantes en ese contexto. La tesis propone estrategias de intervención culturalmente sensibles, orientadas a la prevención y tratamiento del impacto adverso de las mismas.This thesis examines the impact of Adverse Childhood Experiences (ACEs) on physical and mental health during emerging adulthood, taking into account cultural and contextual variables specific to Spain and Latin America. Study 1 focused on a sample of Spanish young adults, addressing the impact of ACEs on physical health—an area that has received little attention during this life stage. Study 2 analysed the relationship between ACEs, coping strategies, and the manifestation of psychopathic and altruistic traits. This study adopts an innovative approach by considering specific combinations of ACEs rather than analysing them in isolation. Study 3 was conducted with a sample of Latin American young adults, expanding the analysis to include expanded ACEs, which take into account economic and social factors relevant to that context. The thesis proposes culturally sensitive intervention strategies aimed at preventing and addressing the adverse impact of such experiences.Programa de Doctorat en Estudis Internacionals de Pau, Conflictes i Desenvolupamen