9300 research outputs found
Sort by
Quantification and characterization of the microstructural damage of recycled aggregate self-compacting concrete under cyclic temperature changes
Get PDFRecycled Aggregate (RA) usually increases porosity and weakens Interfacial Transition Zones (ITZs) of concrete,
which favors the appearance of internal thermal damage. Four Self-Compacting Concrete (SCC) mixes with
coarse and fine RA were subjected to positive and negative cyclic temperature variations to characterize their
thermal damage and quantify its effects. Two damage mechanisms were found. On the one hand, micro-cracks
appeared in the ITZs. On the other hand, micro-cracks arose from the micro-pores and propagated through the
cementitious matrix. Both damage mechanisms were promoted by the use of coarse and fine RA, respectively.
The damage was most notable at sub-zero temperatures and when adding coarse RA. Furthermore, it primarily
affected compressive strength, although ultrasonic pulse velocity and hardened density also decreased, which
served as non-destructive indicators to indirectly quantify the level of thermal internal damage of SCC.This work was funded by MICINN, AEI, EU, ERDF and NextGenerationEU/PRTR [PID2020-113837RB-I00; 10.13039/501100011033; TED2021-129715B-I00; FPU17/03374]; JCyL and ERDF [UIC-231]; and the University of Burgos [SUCONS, Y135.GI]
Estudio de factores humanos en la conducción mediante un simulador de realidad virtual. Análisis pormenorizados de la influencia de la música, el uso del smartphone y la carga mental, en entornos urbanos e interurbanos
Get PDFLos accidentes de tráfico siguen teniendo gran impacto en nuestra sociedad,
provocando gran cantidad de pérdidas humanas. La presente Tesis doctoral ha
realizado varios experimentos con voluntarios y voluntarias, usando un simulador de
conducción de realidad virtual.
La Tesis está formada por cinco publicaciones con varios resultados. Se crea un modelo
conceptual para estudiar el efecto de la música en conductores y conductoras.
Identificación de diferencias de comportamiento, en parámetros de la mirada, cerca y
dentro de las rotondas cuando están expuestos a distracciones. Confirmación de
diferencias, entre conductores o conductoras jóvenes distraídos y no distraídos, su
impacto en el rendimiento, en términos de control del vehículo analizando además la
carga de trabajo. Aumento la probabilidad de cometer una infracción de tráfico con el
uso de aplicaciones de redes sociales mientras se conduce. Análisis de la variabilidad
de donde mira el conductor o conductora en rotondas con y sin distracciones.Traffic accidents continue to have a great impact on our society, causing a large number
of human losses. This doctoral thesis has carried out several experiments with
volunteers using a virtual reality driving simulator.
The thesis consists of five publications with various results. A conceptual model is
created to study the effect of music on male and female drivers. Identification of
behavioural differences in gaze parameters near and inside roundabouts when exposed
to distractions. Confirmation of differences between distracted and non-distracted young
drivers, their impact on performance, in terms of vehicle control and analysing workload.
Increased likelihood of committing a traffic infraction with the use of social networking
applications while driving. Analysis of the variability of where the driver looks at
roundabouts with and without distractions.Los artículos han sido soportados por fondos FEDER (Fondo Europeo de
Desarrollo Regional) dentro del proyecto “Modelización mediante técnicas de
machine learning de la influencia de las distracciones del conductor en la
seguridad vial”
Referencia. BU300P1
La mujer en la enseñanza de la Edad Media: un estudio a partir de los libros informativos
No full textEn los últimos años han surgido preguntas sobre la presencia o ausencia de determinados colectivos en las narrativas escolares. En este contexto, se examinan la presencia de las mujeres de la Edad Media en la historia
escolar detectando concepciones androcéntricas y hallando divergencias con
la historia académica
Diseño de intervención educativa dirigida a cuidadores sanitarios en el ámbito de los centros sociosanitarios para disminuir la resistencia a antibióticos
Get PDFIntroducción: Los antibióticos son considerados como uno de los descubrimientos terapéuticos más importantes para la medicina. Sin embargo, hoy en día debido a las resistencias nos hacemos la pregunta de “¿son los antibióticos nuestros enemigos o nuestros aliados?”. Los pacientes institucionalizados en centros sociosanitarios son uno de los grupos de población que más consumo antibiótico tiene, y es por ello que en esta población existe una gran problemática en cuanto a las resistencias a los antimicrobianos. Objetivos: Diseñar una intervención educativa para trabajadores de centros sociosanitarios, basada en la evidencia, para promover acciones que reducen la propagación de infecciones y así disminuir las resistencias bacterianas. Metodología: Se ha diseñado una intervención educativa sobre la resistencia a antimicrobianos y la prevención de la infección nosocomial en el ámbito sociosanitario. La población diana son enfermeras, auxiliares de enfermería y médicos de los centros sociosanitarios. Esta intervención cuenta con 3 sesiones con partes teóricas y partes prácticas, para favorecer el aprendizaje significativo de los participantes. Evaluación: La intervención será evaluada por medio de cuestionarios pre- intervención y post-intervención que valorarán la adquisición de nuevos conocimientos tras las sesiones educativas. Además, se evaluarán la satisfacción, aspectos estructurales y el impacto de la intervención. Conclusiones: Que la enfermería lleve a cabo educación para la salud a través una intervención educativa sobre la prevención de las resistencias a antimicrobianos y la prevención de las infecciones se considera una acción necesaria para disminuir esta problemática en el ámbito de los centros sociosanitarios.Introduction: Antibiotics are considered one of the most important therapeutic discoveries for medicine. However, today, due to resistance to antibiotics, we ask ourselves the question "Are antibiotics our enemies or our allies?" Patients institutionalized in social health centers are one of the population groups that consume the most antibiotics, and that is why in this population there is a great problem in terms of antibiotic resistance. Objectives: Design an educational intervention for workers in social health centers, based on evidence to promote actions that reduce the spread of infections and thus reduce bacterial resistance. Methodology: An educational intervention on antimicrobial resistance and the prevention of nosocomial infection in the socio-sanitary field has been designed, where the target population will be nurses, nursing assistants and doctors from social-health centers. This intervention has a series of dynamics and theory to promote significant learning of the participants. Evaluation: The intervention will be evaluated by means of a pre-intervention questionnaire and a post-intervention questionnaire that will assess the acquisition of new knowledge after the educational sessions. Conclusions: Carrying out health education through an educational intervention on the prevention of antimicrobial resistance and the prevention of infections is considered necessary to reduce this problem in the field of social health centers
Los viajes del Emperador: una propuesta didáctica paa 2º de ESO basada en el aprendizaje cooperativo
No full textEl presente trabajo de fin de máster se centra en una propuesta didáctica con el aprendizaje
cooperativo como metodología principal. Para ello, en el marco teórico se han analizado las
carencias de la metodología tradicional o clase magistral, así como los beneficios de las
metodologías activas y cómo estas pueden paliar dichas necesidades. Tras esto, se ha
desarrollado una unidad didáctica centrada en el aprendizaje cooperativo, para estudiar el
absolutismo y la figura de Carlos V, con la intención de motivar y hacer reflexionar a los
alumnos sobre este tema, y, en última instancia, trabajar hacia el aprendizaje significativo.This master's thesis focuses on a didactic proposal with cooperative learning as the main
methodology. For this, in the theoretical framework we have analyzed the shortcomings of the
traditional methodology or master class, as well as the benefits of active methodologies and
how they can alleviate these needs. After this, a didactic unit has been developed with
cooperative learning as the main active methodology, to study absolutism and the figure of
Charles V, with the intention of motivating and making students reflect on this topic, and,
ultimately, work towards meaningful learning
Metal-free organocatalysts for high hydrolytic stability single component polyurethane adhesives and their application in decorative insulation facades manufacturing
Get PDFWe focused on developing polyurethane (PU) adhesives with superior ambient thermal and hydrolytic stability, a crucial factor for industrial productivity. Our approach involved creating PU prepolymers that can withstand varying temperatures in ambient conditions. These prepolymers consist of conventional isocyanate-terminated polyurethane and metal-free acid:base organic catalysts, with the stability of the adhesive relying on the organocatalyst employed. We tested a series of 11 latent organocatalysts derived from the reaction between 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and various acids. Among these, the catalyst based on 1-naphthoic acid exhibited exceptional stability, lasting at least 3 h at 60 ◦C and an average relative humidity of 65% under vigorous stirring. We assessed this stability using a fan-based stirrer and analyzed the curing conditions kinetically through DSC. Furthermore, our adhesive formulation is environmentally friendly as it is free of metals, specifically tin (typically present in catalysts such as dibutyltin dilaurate). This quality enhances its sustainability. To validate the practical applicability of the adhesives, we conducted tests using decorative facade models composed of siliciclastic sandstone extracted from a quarry in Vilviestre del Pinar (Burgos, Spain. Latitude: 41.951024◦N, longitude: 3.078283◦W) and extruded polystyrene (XPS). The results demonstrated the excellent hydrolytic and thermal stability of the adhesives, highlighting their significant potential for panel manufacturing in this context.This work was supported by the Regional Government of Castilla y León (Junta de Castilla y León) and by the Ministry of Science and Innovation MICIN and the European Union NextGeneration EU PRTR. Author José Miguel García received grant PID2020-113264RB-I00 funded by MCIN/AEI/ 10.13039/501100011033 and by “ERDF A way of making Europe”. Author Miriam Trigo-López received grant PID2019-108583RJ-I00 funded by MCIN/AEI/10.13039/501100011033. Author Saul Vallejos received grant BG22/00086 funded by Spanish Ministerio de Universidades
Ultrashort pulsed Femtosecond UV laser for selective cleaning of significant Cretaceous flints
Get PDFThis work reports on studies aimed to evaluate the utilization of ultrashort 238 fs (fs) pulsed UV laser emission at 343 nm for eliminating colored crusts and surface deposits on significant Cretaceous flint surfaces, in an attempt to safeguard its aesthetic appearance and archaeological value. The results indicate that fs UV lasers may be an ideal, non-contact tool for selective surface cleaning of sensitive archaeological artefacts, since they enable contaminant desorption while avoiding photothermal damage.Project supported by H2020-MSCA-ITN-EJD/ED-ARCHMAT funding under the Marie Skłodowska-Curie Actions grant agreement, No. 766311 and by Gobierno de Aragón (research group T54_20R)
El orden sucesorio "ab intestato": de Roma al derecho español contemporáneo
No full textEn los supuestos de sucesión ab intestato es preciso que la voluntas testatoris sea suplida, y eso lo hace la ley, el legislador, estableciendo un orden de llamamientos con el que se quiere sustituir la ausencia de voluntad del finado, pero intentando acercarse lo más posible a aquélla que hubiera sido su última voluntad. Pues bien, dicha sucesión intestada, también llamada sucesión legítima, ha sufrido una profunda transformación a lo largo de toda su historia, consecuencia del cambio del parentesco agnaticio, - criterio parental utilizado por el ius civile romano-, por el cognaticio, parentesco de sangre, que termina por imponerse en el derecho justinianeo, estableciéndose así un nuevo sistema de llamada hereditaria intestada que en sus líneas fundamentales ha pasado a las legislaciones modernas. La obra se estructura en tres partes perfectamente diferenciadas: derecho romano, derecho intermedio y derecho español contemporáneo. Cada capítulo se concluye con un apartado de conclusiones, incluyendo en el último una propuesta de lege ferenda de modificación del orden sucesorio establecido en el Código civil
Hydrophobic Deep eutectic Solvents based on cineole and organic acids
Get PDFThe hydrophobic Natural Deep Eutectic Solvent formed by the combination of cineole and decanoic acid (capric acid) was studied using a combined experimental and computational approach. Experimental study was carried considering relevant physicochemical properties as density, viscosity, refraction index and thermal conductivity as a function of temperature, as well as Raman spectra for 785 nm excitation wavelength. Thermophysical properties measured showed a low -viscous low-dense fluid, which is of great relevance for its technological application, as well as the Raman spectra confirmed the formation of hydrogen bonding. The analysis of nanoscopic properties and structuring was carried out using theoretical method as the Density Functional Theory (BP86/def2-TZVP plus Grimme’s D3 theoretical level) and classical Molecular Dynamics simulation (using AMOEBA polarizable force field). Molecular modelling studies using quantum chemistry and classical molecular dynamics methods allowed a nanoscopic characterization of the fluid as well as of its intermolecular forces (hydrogen bonding). Phase equilibria were predicted using COSMO method considered solid–liquid (melting behavior) and vapor – liquid (evaporation), as well as excess properties. The COSMO results showed a low volatile, wide liquid range fluid, characterized by non-ideality because of the formation of hydrogen bonding. Likewise, the interaction of the considered material with POPC lipid was studied using COSMOperm method to analyze its behavior at lipid bilayers as models of cell membranes for the consideration of its possible toxicological effects, showing how the considered molecules are able to penetrate and disrupt the model membranes because of the lipophilic nature of the considered molecules.We acknowledge SCAYLE (Supercomputación Castilla y León, Spain) for providing supercomputing facilities. The statements made herein are solely the responsibility of the authors
Effect of high voltage atmospheric cold plasma on chicken eggs quality during refrigerated storage
Get PDFSalmonellosis outbreaks caused by Salmonella Enteritidis are usually linked to the consumption of eggs and egg products. To assure egg safety, High Voltage Atmospheric Cold Plasma (HVACP) has demonstrated its efficacy in achieving higher than 105 CFU/egg reduction of this bacteria on the egg's surface. Although no quality changes were found immediately after treatment, there was a lack of knowledge on how the quality of HVACP-treated eggs could evolve during their shelf life, and a six-week quality study was performed in this work. Eggs were treated under two sets of conditions, 0.5 min of treatment within 24 h post treatment and 8.5 min of treatment and no post treatment time were the selected ones. No significant differences were found between untreated and treated eggs regarding albumen and yolk pH, Haugh unit, yolk color, vitelline membrane strength or shell strength. The changes detected during the six weeks of storage at 4 °C were attributed to the natural aging of the eggs and not to the effect of HVACP treatments. These results prove HVACP technology as an effective alternative to current techniques to assure both the safety and quality of eggs during their shelf life.This work was supported by Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA), and the Barrett Family Foundation Chair in Sustainable Food Engineering