Desarrollo de materiales compuestos de nitruro de silicio conteniendo nanotubos de carbono: nuevas funcionalidades y aplicaciones

Tesis doctoral inédita. Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Química Inorgánica. Fecha de lectura: 13-01-201

EEG Analysis during Music Perception

This review presents the most interesting results of electroencephalographic studies on musical perception performed with different analysis techniques. In first place, concepts on intra-musical characteristics such as tonality, rhythm, dissonance or musical syntax, which have been object of further investigation, are introduced. Most of the studies found use listening musical extracts, sequences of notes or chords as an experimental situation, with the participants in a resting situation. There are few works with participants performing or imagining musical performance. The reviewed works have been divided into two groups: a) those that analyze the EEGs recorded in different cortical areas separately using frequency domain techniques: spectral power, phase or time domain EEG procedures such as potentials event related (ERP); b) those that investigate the interdependence between different EEG channels to evaluate the functional connectivity between different cortical areas through different statistical or synchronization indices. Most of the aspects studied in music-brain interaction are those related to musical emotions, syntax of different musical styles, musical expectation, differences between pleasant and unpleasant music and effects of musical familiarity and musical experience. Most of the works try to know the topographic maps of the brain centers, pathways and functions involved in these aspects

Characterization and computation of control invariant sets within target regionsfor linear impulsive control systems

Linear impulsively controlled systems are suitable to describe a venue of real-life problems, going from disease treatment to aerospace guidance. The main characteristic of such systems is that they remain uncontrolled for certain periods of time. As a consequence, punctual equilibria characterizations outside the origin are no longer useful, and the whole concept of equilibrium and its natural extension, the controlled invariant sets, needs to be redefined. Also, an exact characterization of the admissible states, i.e., states such that their uncontrolled evolution between impulse times remain within a predefined set, is required. An approach to such tasks -- based on the Markov-Lukasz theorem -- is presented, providing a tractable and non-conservative characterization, emerging from polynomial positivity that has application to systems with rational eigenvalues. This is in turn the basis for obtaining a tractable approximation to the maximal admissible invariant sets. In this work, it is also demonstrated that, in order for the problem to have a solution, an invariant set (and moreover, an equilibrium set) must be contained within the target zone. To assess the proposal, the so-obtained impulsive invariant set is explicitly used in the formulation of a set-based model predictive controller, with application to zone tracking. In this context, specific MPC theory needs to be considered, as the target is not necessarily stable in the sense of Lyapunov. A zone MPC formulation is proposed, which is able to i) track an invariant set such that the uncontrolled propagation fulfills the zone constraint at all times and ii) converge asymptotically to the set of periodic orbits completely contained within the target zone.Fil: Sánchez, Ignacio Julián Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Matemática Aplicada del Litoral. Universidad Nacional del Litoral. Instituto de Matemática Aplicada del Litoral; ArgentinaFil: Louembet, Christophe. Centre National de la Recherche Scientifique; Francia. Universite de Toulose - Le Mirail; FranciaFil: Actis, Marcelo Jesús. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química; ArgentinaFil: González, Alejandro Hernán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentin

Examining the psychometric properties of the burnout clinical subtype questionnaire (BCSQ-12) in secondary school teachers

Based on Farber’s burnout proposal, the first aim of this study was to examine the psychometric properties of the short version of the Burnout Clinical Subtype Questionnaire (BCSQ-12) in secondary school teachers. The second aim of the study was to examine possible differences in the burnout subtypes in terms of gender, type of school, and teaching experience. Two different samples of 584 (M¿=¿45.04; 43% males) and 106 (M¿=¿45.50; 40% males) secondary school teachers participated in the study. Results obtained from both the exploratory structural equation modeling (ESEM) and the confirmatory factor analysis (CFA) supported the three-factor structure of the BCSQ-12, comprised of overload, lack of development, and neglect. Further, the BCSQ-12 showed adequate composite reliability. The negative relationships between the three-factor structure of burnout, teachers’ basic psychological need satisfaction, and teachers’ job satisfaction provide evidence of the nomological validity of BCSQ-12. Finally, female teachers, state school teachers, and experienced teachers reported a greater risk of suffering one or more of these three burnout subtypes. Theoretical, methodological, and practical contributions of the BCSQ-12 are discussed, highlighting the importance of assessing the three burnout subtypes separately

Measuring the impact of haptic feedback in collaborative robotic scenarios

[EN] In recent years, the interaction of a human operator with teleoperated robotic systems has been much improved. One of the factors influencing this improvement is the addition of force feedback to complement the visual feedback provided by traditional graphical user interfaces. However, the users of these systems performing tasks in isolated and safe environments are often inexperienced and occasional users. In addition, there is no common framework to assess the usability of these systems, due to the heterogeneity of applications and tasks, and therefore, there is a need for new usability assessment methods that are not domain specific. This study addresses this issue by proposing a measure of usability that includes five variables: user efficiency, user effectiveness, mental workload, perceived usefulness, and perceived ease of use. The empirical analysis shows that the integration of haptic feedback improves the usability of these systems for non-expert users, even though the differences are not statistically significant; further, the results suggest that mental workload is higher when haptic feedback is added. The analysis also reveals significant differences between participants depending on gender.SIPublicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL

Analysis of the success in soccer match officials' decisions during an international tournament according to contextual factors

[EN] This study examined the reliability of the ARBI.e tool as a notational system to observe, code and analyse match officials decisions in soccer, and analysed the degree of success in referee decisions during an international tournament according to contextual factors (e.g., period of the match, competition phase and score) and the zone of the soccer field. Sixty international field referees (FR) and assistant referees (AR) were analysed in this study. Referee decisions were registered during thirty soccer matches of an international tournament and categorized (e.g., FR, AR and other decisions) for further analysis. The tool ARBI.e was an ad hoc tool created by the authors to assess match official decisions. Cohen's Kappa statistic showed values of 0.914-1.00 and 0.827-1.00 for intra-observer and inter-observer analysis, respectively. Despite the high level of success in both FR and AR (95%), some decisions, such as simulations or offside, showed substantially lower success values (64% and 92%, respectively). Besides, match officials' decisions success was not influenced by the period of the match, tournament phase and score or indeed by the zone of the soccer field. The results obtained suggest the need to include activities based on decision-making skills, mainly in simulations, in training programs to optimize international match officials' decision making[ES] Este estudio examinó la confiabilidad de la herramienta ARBI.e como sistema notacional para observar, codificar y analizar las decisiones en partidos oficiales de fútbol, y analizó el grado de éxito en las decisiones arbitrales durante un torneo oficial atendiendo a factores contextuales (p.e., periodo del partido, fase de la competición y marcador) y a la zona del campo. Sesenta árbitros internacionales (FR) y asistentes (AR) fueron analizados en este estudio. Las decisiones arbitrales fueron registradas durante 30 partidos de fútbol, pertenecientes a un torneo internacional, los cuales se categorizaron (p.e., FR, AR y otras decisiones) para el posterior análisis. La herramienta ad hoc ARBI.e fue creada por los autores para valorar las decisiones arbitrales. El coeficiente Kappa de Cohen mostró valores desde 0,914 a 1,00 y desde 0,827 a 1,00 para el análisis intra-observador e inter-observador, respectivamente. A pesar del alto nivel de éxito en ambos grupos, FR y AR (95%), algunas decisiones, como las simulaciones o fuera de juego, mostraron un valor de éxito sustancialmente menor (64% y 92%, respectivamente). Por otro lado, el éxito en las decisiones durante los partidos oficiales no estuvo influenciado por el periodo del partido, la fase del torneo y el resultado, ni por la zona del campo en la que tenía lugar la acción. Los resultados obtenidos sugieren que es necesario incluir actividades basadas en habilidades de toma de decisiones, principalmente simulaciones, en programas de entrenamiento para optimizar la toma de decisiones durante los partidos oficiales

Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

"Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAM"Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22–0.47; p < 0.001) for tocilizumab, 0.82 (0.71–1.30; p 0.82) for IHDC, 0.61 (0.43–0.86; p 0.006) for PDC, and 1.17 (0.86–1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02–0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situation.In addition, Juan Berenguer, Jesús Rodríguez-Baño, Inmaculada Jarrín, Jordi Carratalá, Jerónimo Pachón, and José R Arribas received funding for research from Plan Nacional de IþDþi 2013-2016 and Instituto de Salud Carlos III, Subdirecci on General de Redes y Centros de Investigaci on Cooperativa, Ministerio de Ciencia, Innovaci on y Universidades e co- financed by European Development Regional Fund “A way to achieve Europe”, Operative program Intelligent Growth 2014e2020 through the networks: Spanish AIDS Research Network (RIS) [RD16/0025/0017 (JB), RD16/0025/0018 (JRA), RD16/ 0025/00XX (IJ)] and Spanish Network for Research in Infectious Diseases (REIPI)[RD16/0016/0001 (JRB), RD16/0016/0005 (JC), and RD16/0016/0009 (JP)

Understanding the links between the composition-processing-properties in new formulations of heas sintered by sps

This work presents two new compositions of high entropy alloys (HEAs) that were designed with the aim of obtaining a body-centered cubic (BCC) phase with high hardness values and a moderate density. Sintering was performed using Spark Plasma Sintering (SPS) with different heating rates to determine the influence of the processing parameters on the phase formation. The microstructural study revealed that the presence of Ni in the composition promoted phase separation, and the mechanical study confirmed a clear influence on the mechanical properties of both the composition and heating rate. The combination of microscopy with compression and nanoindentation tests at room and high temperature made it possible to advance our understanding of the relationships between the composition, processing, and properties of this emerging group of alloys

Desarrollo de catalizadores basados en ligandos NHC funcionalizados con aplicación en procesos químicos sostenibles

El trabajo desarrollado en esta Memoria se ha centrado en la síntesis, caracterización y estudio de las posibles aplicaciones en catálisis de compuestos organometálicos de rodio, iridio, cobre y manganeso que contienen ligandos tridentados basados en el esqueleto central de la 2,6-lutidina doblemente funcionalizado asimétricamente. Los ligandos, de fórmula general NHC-Py-L, poseen un fragmento NHC en uno de los brazos laterales del fragmento 2,6-lutidina y un grupo dador L potencialmente hemilábil (L = OMe, NEt2, NHtBu) en el otro. Se han preparado una serie de compuestos neutros y catiónicos de rodio(I) e iridio(I) que incorporan la diolefina 1,5-ciclooctadieno y los ligandos NHC funcionalizados coordinados de forma monodentada, bidentada ó tridentada. El estudio de la reactividad de estos compuestos con monóxido de carbono y dihidrógeno han permitido acceder a compuestos con una gran variedad estructural, algunos de ellos con el ligando NHC coordinado de forma pincer. Adicionalmente, se han sintetizado compuestos de rodio(III) e iridio(III) en los que se ha producido una activación C-H de uno de los metilos del grupo t-butilo del ligando NHC, lo que resulta en una coordinación tetradentada del ligando NHC-Py-L. Asimismo, se han sintetizado compuestos catiónicos de manganeso(I) con los ligandos coordinados de forma pincer y compuestos de cobre(I) que presentan una estructura polimérica en estado sólido y previsiblemente tetranuclear en disolución.Los compuestos de iridio sintetizados son catalizadores eficientes en los procesos de autotransferencia de hidrógeno de β-alquilación de alcoholes y N-alquilación de aminas con alcoholes primarios. Además, estos compuestos de iridio(I) proporcionan excelentes resultados en reacciones de N-metilación de aminas y de nitrocompuestos con metanol que actúa como fuente C1 y como disolvente. Estudios experimentales han demostrado la importancia de los procesos de cooperación metal-ligando (MLC), por desaromatización/aromatización del anillo de piridina, en la preactivación del catalizador y en el ciclo catalítico operante facilitando la generación de especies metal-hidruro activas por activación del alcohol correspondiente. Por otra parte, los compuestos de rodio se han aplicado en reacciones de hidrosililación de alquinos, tanto terminales como internos, con buena selectividad al derivado β(Z)-vinilsilano. Ha sido posible identificar especies Rh(III)-H por adición oxidante del silano al precursor de catalizador lo que sugiere que las reacciones transcurren a través de un mecanismo Chalk-Harrod modificado. Se han preparado polímeros de coordinación de cobre(I) que son extraordinariamente eficientes en la reacción de cicloadición [3+2] de azidas y alquinos lo que ha permitido la preparación de 1,2,3-triazoles sustituidos en las posiciones 1 y 4 utilizando un amplio rango de alquinos. Por último, los compuestos de manganeso(I) son moderadamente activos en la hidrosililación de CO2 a sililformiato. La gran actividad y selectividad mostrada por los catalizadores en los procesos catalíticos objeto de estudio ha permitido disminuir la carga de catalizador de iridio a valores del 0.1 mol% en las reacciones de β-alquilación y N-alquilación, y a valores en el rango de 0.5-2.5 mol% en las reacciones de N-metilación de aminas y nitro derivados. En el caso de las reacciones de cicloadición [3+2] de azidas y alquinos la carga de catalizador de cobre puede reducirse hasta el 0.0025 mol% (25 ppm) con tiempos de reacción aceptables. En consecuencia, los catalizadores basados en ligandos NHC-Py-L están a la altura de los sistemas más activos previamente descritos en la bibliografía.<br /