King Juan Carlos University
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Continuous Production of Methyl Lactate from Hemicellulosic Sugars: Identifying and Sorting out Sn-USY-Based Catalyst Deactivation
No full textPotassium-exchanged tin-functionalized USY zeolite ([K]Sn-USY) has been studied in the continuous transformation of glucose, xylose, and their mixtures in a fixed-bed reactor for the production of methyl lactate at 150 degrees C. The catalyst efficiently drives the transformation of all the studied substrates, though it faces several deactivation mechanisms, especially in the case of hexoses. Potassium leaching from the catalyst and organic deposition adduced to furanics produced during the reaction were ascribed as the major deactivation causes. The addition of small amounts (10 mg/kg) of potassium (as KCl or KOH) alleviated the catalyst deactivation, allowing the latter stable methyl lactate production over 30% yield for over 140 h from individual carbohydrates and complex sugar mixtures like Scots Pine hemicellulose hydrolysates
Social Aspects of Problematic Smartphone Use: Development and Validation of the PSSNUS and Mental Health Implications for Spanish Youth
No full textPurpose: Addressing the complex pattern of digital behaviors and interactions among youth, this research introduces a novel comprehensive scale, the Problematic Smartphone and Social Network Use Scale (PSSNUS), meticulously developed and validated across five studies. Methods: Using a mixed-methods approach across five stages, including focus groups (Study 1; n = 31), cognitive interviews (Study 2; n = 16), exploratory factor analysis (Study 3; n = 316), and expert panel (Study 4; n = 4), this procedure reduced 58 initial items to an 18-item scale. Subsequently, a confirmatory factor analysis and further analyses (Study 5; n = 355) examined the factorial structure's replicability, reliability, and validity of the scale. Results: The PSSNUS manifested as a reliable (omega ranging 0.70-0.89) instrument, comprising a structure with five key factors (x2 = 173.994, df = 125, p = 0.002, CFI = 0.994, CFI = 0.993, SRMR = 0.039, and RMSEA = 0.027) that capture both individual and social aspects of this construct: Psychological dependence (PD), Online interaction preference (OIP), Digital recognition desire (DRD), Social networks control seeking (SNCS), and Productivity loss (PL). Minor gender differences in both the DRD factor and in the overall score were found, with females scoring higher. The PSSNUS showed convergent and divergent validity through significant but modest correlations with daily smartphone usage hours, procrastination, emotional intelligence and mental health symptomatology (anxiety, depression and stress). This measure further exhibited incremental validity, controlling for other possible predictors, regarding anxiety, depression, and stress (6.5, 11.5 and 7.5% of additional variance explained), highlighting the DRD dimension's unique predictive power. Conclusion: Emerging as a solid instrument, the PSSNUS broadens the concept of problematic smartphone use among young Spaniards to include social functioning aspects, serving as an interesting tool for those aiming to explore further the adverse influence of digital media on youth
Counterfactual Explanations for Sustainable Tourism Indicators
No full textCounterfactual explanations are a well-known technique in Explainable Machine Learning (XML) to provide simple explanations on complex Machine Learning (ML) models. Through understandable "what if" scenarios, counterfactuals explore how changes in the input data affect the results of a model. This article leverages counterfactual explanations for sustainable tourism, an emerging approach within the tourism industry to mitigate the negative impacts of mass tourism on ecological systems and local communities. The proposed method analyzes the relationships between several Sustainable Tourism Indicators (STIs) defined for a specific tourist destination and its general sustainability assessment. It identifies the key changes needed in the STIs to achieve an improved global sustainability score. As a result, a decision-making system is offered for sustainable tourism management, which domain experts can use to make more informed decisions. The effectiveness of the proposed method is illustrated through its application to Mallorca, a popular Spanish tourist destination
Del fondo pintado a los escenarios virtuales
No full textEl artículo aborda la evolución de la plástica escénica como elemento que se transforma desde la acción del intérprete y la posibilidad de participación de la audiencia. Se toman como referencia algunas intervenciones del espacio público que difuminan las fronteras entre los géneros artísticos, entendidas como representaciones en espacios no convencionales. Se destaca la importancia de la participación para redefinir la escenografía más allá de su papel decorativo, a través de obras donde se integra lo visual en la dramaturgia de la obra, fusionando la presencia del cuerpo en escena con la expresión plástica; o intervenciones en las que se modifica la percepción de la audiencia sobre el entorno físico. En este documento se describe de qué manera se produce una transformación del espacio por medio de los dispositivos, abordando la convergencia de las tecnologías digitales y las artes escénicas para mostrar un recorrido por proyectos donde se comienzan a utilizar -de una manera incipiente- tecnologías que empiezan a ser accesibles como la realidad aumentada, la visión artificial y los sistemas interactivos, hasta experiencias inmersivas más vigentes. En conclusión, el artículo examina una evolución de la plástica escénica a través del concepto de participación; fusionando el arte, la tecnología y el espacio público para crear experiencias artísticas únicas y transformadoras
Scapegoating Human Smugglers: How Migrants' Accounts Challenge the EU's Dominant Narrative
No full textThis article applies a migrant-centered approach to examine how first-hand accounts challenge the EU's dominant portrayal of the role of human smugglers. Based on one-hundred semi-structured interviews with migrants in Europe and North Africa, the analysis explores human smugglers' degree of influence on migrants' decisions and the extent of deception involved in unauthorized journeys. The findings reveal that their role in decision-making is highly overstated, challenging their widespread vilification and portrayal as primary instigators of irregular migration. It concludes with a discussion on how inaccurate portrayals may serve as a powerful discursive device sustaining ineffective policies with undeclared intentions
Assessment study of insight ARTHRO VR (R) arthroscopy virtual training simulator: face, content, and construct validities
No full textThe aims of this study were to test the face, content, and construct validities of a virtual- reality haptic arthroscopy simulator and to validate four assessment hypothesis. The participants in our study were 94 arthroscopists attending an international conference on arthroscopy. The interviewed surgeons had been performing arthroscopies for a mean of 8.71 years (sigma = 6.94 years). We explained the operation, functionality, instructions for use, and the exercises provided by the simulator. They performed a trial exercise and then an exercise in which performance was recorded. After having using it, the arthroscopists answered a questionnaire. The simulator was classified as one of the best training methods (over phantoms), and obtained a mark of 7.10 out of 10 as an evaluation tool. The simulator was considered more useful for inexperienced surgeons than for surgeons with experience (mean difference 1.88 out of 10, P value < 0.001). The participants valued the simulator at 8.24 as a tool for learning skills, its fidelity at 7.41, the quality of the platform at 7.54, and the content of the exercises at 7.09. It obtained a global score of 7.82. Of the subjects, 30.8% said they would practise with the simulator more than 6 h per week. Of the surgeons, 89.4% affirmed that they would recommend the simulator to their colleagues. The data gathered support the first three hypotheses, as well as face and content validities. Results show statistically significant differences between experts and novices, thus supporting the construct validity, but studies with a larger sample must be carried out to verify this. We propose concrete solutions and an equation to calculate economy of movement. Analogously, we analyze competence measurements and propose an equation to provide a single measurement that contains them all and that, according to the surgeons' criteria, is as reliable as the judgment of experts observing the performance of an apprentice
Social media and self-harm Twitter analysis
No full textProject “Media representation of self-harm by minors in the media and Networks” (PID2021-124550OB-I00) framed within the call for Knowledge Generation Projects 2021, subsidized by the National Plan of the Ministry of Science and Innovation.This technical report aims to raise awareness of the codes of self-harming behavior in the digital environment, especially in the case of Twitter
A Global Approach to the Design and Evaluation of Virtual Reality Medical Simulators
No full textVR Simulators are a powerful alternative to traditional educational techniques in many domains; and in particular, in surgery. Although they offer new possibilities for learning, training and assessment, they still found difficult to be accepted and integrated into hospitals. In this paper, we explain what we consider the key issues to create successful VR simulators, and we present two methodologies: the guidelines for the simulator design and the evaluation of their validity. Research on VR surgical simulators should be interdisciplinary. It involves medicine, educational psychology, computer science, and engineering. Optimal interdisciplinary communication is difficult, and most projects in surgical simulation are strongly influenced by the engineering perspective, with little or no contributions from the others. This unbalance often leads to a premature end of the project or to simulators which are less practical for surgeons. A design methodology should be used as a guide in the process of creating VR simulators. A thorough description of the problem, the simulator's role, and an exhaustive task analysis will lead to the identification of the requirements. For the technical implementation, decisions will be taken related to the hardware interface and the interaction that users will have with the virtual world; which will determine collision detection and response algorithms, and the behaviour of the 3D models. In addition to the technical testing, it is necessary to prove the validity of the simulator and design procedures to measure the user performance. We explain a methodology to evaluate the validity (face, content, and criterion-related validity), reliability and transfer of skills from a VR simulator to the real environment in a structured and rigorous way. Following this methodology, an evaluation experiment involving 19 orthopaedic doctors using a VR arthroscopy simulator was carried out. Results prove face and content validities, and inform about the factors and measures that are considered important for arthroscopic surgery. In order to consolidate the research results, we encourage the establishment of an intersectorial consortium with agents from the academic, healthcare and industrial sectors to ensure the long-term sustainability of research lines, additional funding, and to guarantee that simulators, once validated, can be widely available in hospitals. This paper presents a global approach including relevant guidelines and methodologies for designing and evaluating VR simulators. It can provide a solid structure for other researchers when facing those processes and contribute to the successful integration of VR simulators within the educational curriculum
Evaluación de una metodología activa mixta con estudiantes del Grado de Enfermería en los seminarios prácticos
No full textDiferentes normativas docentes sobre la educación universitaria promueven la innovación docente y el uso de metodologías activas. Este estudio evalúa la efectividad una metodología activa mixta, combinando Aprendizaje Cooperativo y Colaborativo con otros metodología, en estudiantes de 3º curso del Grado de Enfermería. Se realizó durante los cursos 2023-24 y 2024-25 en la asignatura Enfermería Familiar y Comunitaria, con seminarios prácticos de 2 horas. Los estudiantes se dividieron en grupos pequeños para fomentar la interacción. Las variables fueron la satisfacción de los estudiantes, los roles grupales y la utilidad de la metodología. Los resultados fueron satisfactorios, siendo la valoración global superior a 4,2 sobre 5. Destacar, la importación de la evaluación continua para ir valorando la idoneidad de la metodología en cada seminario, mediante el recurso interactivo de Wooclap. En conclusión, la realización de metodologías activas combinadas mejora la satisfacción y motivación de los estudiantes haciéndoles más reflexivos y participativos
Authentic leadership and personal and job demands/resources: A person-centered approach and links with work-related subjective well-being
No full textThe job demands-resources theory considers an open group of personal and job demands and resources. Thus, it allows us to include personal resources not yet covered (i.e., vigor at work) or less explored (i.e., emotional abilities), as well as personal demands not yet explored (i.e., overcommitment). Additionally, from this theory, it is proposed that leaders may influence employee wellbeing. Therefore, of particular interest is to analyze positive leadership styles, such as authentic leadership (AL). This study addresses three research objectives: 1) to identify profiles of employees from a person-centered approach, combining personal resources (self-perception of emotional abilities, vigor at work and self-efficacy) and personal demands (overcommitment) with job resources and demands; 2) to analyze the relation of the identified profiles with indicators of work-related subjective well-being; and 3) to acknowledge whether the AL style determines the pertaining to a profile probability. A large heterogeneous sample of Spanish employees (N = 968) responded to a questionnaire. Data were analyzed by adopting a person-centered approach using latent profile analysis. The results revealed five patterns of job and individual characteristics: Profile 5 (very low personal resources, and low job resources and demands); Profile 4 (low resources and high demands); Profile 3 (mid-level personal resources, high job resources and low demands); Profile 2 (high personal resources, mid-level job resources and high demands); and Profile 1 (high resources and low demands). Analyses showed that workers differed significantly in well-being depending on their profile membership, with Profile 1 having the highest well-being. Profiles that yielded the worst outcomes were Profile 4 and Profile 5, especially the latter. Finally, the results indicated that AL increased the probability that a profile would show a high well-being level