On the reduction of 4-oxo-4h-benzopyran-3-carbaldehydes : global and local electrophilicity patterns

The theoretical global and local electrophilicity patterns of substituted and chelated 4-oxo-4H-benzopyran-3-carbaldehydes (formylchromones) have been evaluated using the electrophilicity index proposed by Parr et al [J. Am. Chem. Soc. 1999, 121, 1922]. The complexation of formylchromones with aluminum predicts a strong electrophilic character of these compounds against nucleophiles. Local response at the active sites may also be assessed in terms of a global contribution described by the global electrophilicity, and a local contribution described by the variations in electrophilic Fukui function at those sites. The highest local electrophilicity is found at the formyl group of the chelated formylchromones, in spite of that, the highest positive charge is located on the pyrone carbonyl group. This result is consistent with the experimental observed reactivity displayed by 4-oxo-4H-benzopyran-3-carbaldehydes in the presence of 2-propanol and alumina

Estudio de patrones de interacción entre los estudiantes y la Plataforma de Tele-Enseñanza en la UPM

Vivimos en una sociedad en la que la información ha adquirido una vital importancia. El uso de Internet y el desarrollo de nuevos sistemas de la información han generado un ferviente interés tanto de empresas como de instituciones en la búsqueda de nuevos patrones que les proporcione la clave del éxito. La Analítica de Negocio reúne un conjunto de herramientas, estrategias y técnicas orientadas a la explotación de la información con el objetivo de crear conocimiento útil dentro de un marco de trabajo y facilitar la optimización de los recursos tanto de empresas como de instituciones. El presente proyecto se enmarca en lo que se conoce como Gestión Educativa. Se aplicará una arquitectura y modelo de trabajo similar a lo que se ha venido haciendo en los últimos años en el entorno empresarial con la Inteligencia de Negocio. Con esta variante, se pretende mejorar la calidad de la enseñanza, agilizar las decisiones dentro de la institución académica, fortalecer las capacidades del cuerpo docente y en definitiva favorecer el aprendizaje del alumnado. Para lograr el objetivo se ha decidido seguir las etapas del Knowledge Discovery in Databases (KDD), una de las metodologías más conocidas dentro de la Inteligencia de Negocio, que describe el procedimiento que va desde la selección de la información y su carga en sistemas de almacenamiento, hasta la aplicación de técnicas de minería de datos para la obtención nuevo conocimiento. Los estudios se realizan a partir de la información de la activad de los usuarios dentro la plataforma de Tele-Enseñanza de la Universidad Politécnica de Madrid (Moodle). Se desarrollan trabajos de extracción y preprocesado de la base de datos en crudo y se aplican técnicas de minería de datos. En la aplicación de técnicas de minería de datos, uno de los factores más importantes a tener en cuenta es el tipo de información que se va a tratar. Por este motivo, se trabaja con la Minería de Datos Educativa, en inglés, Educational Data Mining (EDM) que consiste en la aplicación de técnicas de minería optimizadas para la información que se genera en entornos educativos. Dentro de las posibilidades que ofrece el EDM, se ha decidido centrar los estudios en lo que se conoce como analítica predictiva. El objetivo fundamental es conocer la influencia que tienen las interacciones alumno-plataforma en las calificaciones finales y descubrir nuevas reglas que describan comportamientos que faciliten al profesorado discriminar si un estudiante va a aprobar o suspender la asignatura, de tal forma que se puedan tomar medidas que mejoren su rendimiento. Toda la información tratada en el presente proyecto ha sido previamente anonimizada para evitar cualquier tipo de intromisión que atente contra la privacidad de los elementos participantes en el estudio. ABSTRACT. We live in a society dominated by data. The use of the Internet accompanied by developments in information systems has generated a sustained interest among companies and institutions to discover new patterns to succeed in their business ventures. Business Analytics (BA) combines tools, strategies and techniques focused on exploiting the available information, to optimize resources and create useful insight. The current project is framed under Educational Management. A Business Intelligence (BI) architecture and business models taught up to date will be applied with the aim to accelerate the decision-making in academic institutions, strengthen teacher´s skills and ultimately improve the quality of teaching and learning. The best way to achieve this is to follow the Knowledge Discovery in Databases (KDD), one of the best-known methodologies in B.I. This process describes data preparation, selection, and cleansing through to the application of purely Data Mining Techniques in order to incorporate prior knowledge on data sets and interpret accurate solutions from the observed results. The studies will be performed using the information extracted from the Universidad Politécnica de Madrid Learning Management System (LMS), Moodle. The stored data is based on the user-platform interaction. The raw data will be extracted and pre-processed and afterwards, Data Mining Techniques will be applied. One of the crucial factors in the application of Data Mining Techniques is the kind of information that will be processed. For this reason, a new Data Mining perspective will be taken, called Educational Data Mining (EDM). EDM consists of the application of Data Mining Techniques but optimized for the raw data generated by the educational environment. Within EDM, we have decided to drive our research on what is called Predictive Analysis. The main purpose is to understand the influence of the user-platform interactions in the final grades of students and discover new patterns that explain their behaviours. This could allow teachers to intervene ahead of a student passing or failing, in such a way an action could be taken to improve the student performance. All the information processed has been previously anonymized to avoid the invasion of privacy

Interplay of Support Chemistry and Reaction Conditions on Copper Catalyzed Methanol Steam Reforming

A series of Cu catalysts supported on SiO2, Al2O3-SiO2, TiO2 rutile, and Cu/TiO2 anatase metal oxides has been studied for methanol reforming in the vapor phase. The highest activity was obtained on Cu/SiO2 catalysts (5493 μmol H2 min-1·gcat -1) followed by Cu/TiO2 rutile, Cu/Al2O3-SiO2, and anatase. XRD and HRTEM characterization after reaction revealed that on Cu/SiO2 significant sintering occurred during reaction. In contrast, the particle size growth on Cu/TiO2 rutile and anatase was less pronounced, which could be associated with the interaction between Cu clusters and TiO2. Characterization by TGA showed that on Cu/Al2O3-SiO2 the main cause of deactivation was coke deposition.</p

Improved thermochemical energy storage behavior of manganese oxide by molybdenum doping

To improve the thermochemical energy storage (TCS) behavior of Mn2O3, several Mn–Mo oxides with varying amounts of MoO3 (0–30 wt%) were prepared by a precipitation method. The physico-chemical properties of the solids were studied byN2 adsorption–desorption, X-ray diffraction (XRD), scanning electron microscopy (SEM), and H2-temperature-programmed reduction (TPR), while their TCS behavior was determined by thermogravimetric analysis coupled with differential scanning calorimetry (TGA-DSC). Apart from Mn2O3 and MoO3 phases, XRD revealed a mixed MnMoO4 phase for MoO3 loadings equal or higher than 1.5 wt%. All samples showed a wellformed coral-like surface morphology, particularly those solids with low MoO3 contents. This coral morphology was progressively decorated with compact and Mo-enriched MnMoO4 particles as the MoO3 content increased. TPR revealed that the redox behavior of Mn2O3 was significantly altered upon addition of Mo. The TCS behavior of Mn2O3 (mostly oxidation kinetics and redox cyclability) was enhanced by addition of low amounts of Mo (0.6 and 1.5% MoO3) without significantly increasing the reduction temperature of the solids. The coral morphology (which facilitated oxygen diffusion) and a smoother transition from the reduced to oxidized phase were suggested to be responsible for this improved TCS behavior. The samples containing 0.6 and 1.5 wt% of MoO3 showed outstanding cyclability after 45 consecutive reduction–oxidation cycles at high temperatures (600–1000 C). These materials could potentially reach absorption efficiencies higher than 90% at concentration capacity values typical of concentrated solar power plants

A New Methodology to Construct a Database of World University Exams

[EN] How can we improve the homogenization of university education around the world? This is the central question of our research. In order to answer it, we focus on the classic tool used to evaluate students: exams. The aim of our paper is to establish a methodology with which to construct a database of world university exams by academic field. The database would be available to professors and students worldwide, and both categories could use it to contrast their level in a certain subject. In this sense, our proposal aims to achieve two objectives: 1) to maximize the effectiveness of exams as a measurement of students´ knowledge; 2) to use exams as a tool to homogenize education within universities in a certain academic field.Pinar-Pérez, JM.; Fernandez-Moya, M.; Cuadros-Solas, P.; Salvador, C.; Morales-Arsenal, R. (2021). A New Methodology to Construct a Database of World University Exams. En Proceedings INNODOCT/20. International Conference on Innovation, Documentation and Education. Editorial Universitat Politècnica de València. 89-94. https://doi.org/10.4995/INN2020.2020.11822OCS899

Mitigating deficiencies of generation Z through new educational methodologies in a business statistic course

[EN] Nowadays, most of the students in first course at University are from the socalled Generation Z. Since a young age, these students have been used digital technology such as internet, mobile phones, tablets and laptops developing certain skills. But a large majority of these students have some deficiencies such as low knowledge of mathematics, scarce levels of motivation, concentration or logical reasoning and little patience (they want to understand everything quickly). These characteristics must be improved being a hard work to do by teachers. New educational methodologies are being adapted taking into account these digital skills and mitigating the deficiencies observed in some students. This paper presents an analysis of the impact of using new methodological techniques in a business statistics course. The work focuses on the problem of increase the student´s motivation through the use of new digital tools such as video-lessons, screencasts and flipped classroom combined with neuroeducation techniques. Our hypothesis is mitigating the deficiencies of students through increasing their motivation. A multiple linear regression model to a set of students is carried out. Empirical results show, in general, that females take advantage of this methodology implemented better than males. Moreover, students with “good” performance reach better outputs (higher final score and a deeper knowledge of the subject) if additional methodological tools are implemented in the traditional class. While, there is not improvement for “bad” students.Pinar-Pérez, JM.; Morales-Arsenal, R.; Fernandez-Moya, M.; Cuadros-Solas, P.; Salvador, C. (2021). Mitigating deficiencies of generation Z through new educational methodologies in a business statistic course. En Proceedings INNODOCT/20. International Conference on Innovation, Documentation and Education. Editorial Universitat Politècnica de València. 81-88. https://doi.org/10.4995/INN2020.2020.11821OCS818

Sistema de gestión de energía para microrredes basado en control predictivo

En este artículo se presenta un sistema de gestión de energía para microrredes a partir de un control Predictivo basado en Modelos (MPC), el cual tiene como tarea la optimización de las operaciones de una microrred, al tiempo que cumple una serie de restricciones de funcionamiento. Para ello, el problema ha sido formulado empleando Programación Lineal Entera-Mixta (MILP), la cual ha sido resuelta de manera eficiente. Se han estudiado diferentes escenarios, comparando el MPC con una estrategia fija y se han calculado costes de funcionamiento e inversión, mostrando finalmente los resultados.Los autores quieren agradecer a la Universitat Jaume I y a la Generalitat Valenciana el apoyo recibido y materializado en los proyectos P11B2013-34 y GV/2014/117 respectivamente

Control de la tensión del bus de continua de un filtro activo mediante un convertidor DC-DC

En este artículo se presentan los resultados experimentales obtenidos mediante un sistema compensador generador trabajando de forma aislada de la red eléctrica. Para analizar el funcionamiento del sistema se ha desarrollado un prototipo de un convertidor DC-DC bidireccional el cual permite adaptar el valor de la tensión de las baterías conectadas a su entrada con la tensión del bus de continua a la entrada del filtro activo. Para el control del convertidor DC-DC se ha utilizado un control por realimentación del estado diseñado mediante algoritmos genéticos, y en el caso del filtro activo se ha utilizado un control proporcional con prealimentación. Los resultados experimentales obtenidos muestran el correcto funcionamiento del sistema tanto en estado estacionario, como en régimen transitorio.Los autores quieren agradecer a la Universitat Jaume I y a la Generalitat Valenciana el apoyo recibido y materializado en los proyectos P11B2013-34 y GV/2014/117 respectivamente

Disinfection of dental impressions, disinfectant solutions and disinfection methods. Literature review

La toma de impresiones en Odontología es un procedimiento frecuentemente realizado y su contaminación por microorganismos presentes en la flora bucal exige que sea sometida a un procedimiento de desinfección después de ser retirada de boca, para reducir al máximo los riesgos de infección cruzada tanto en la clínica como en el laboratorio. Las impresiones pueden ser fuente de transmisión de infecciones entre el odontólogo y el laboratorio debido al contacto con saliva y sangre del paciente, que luego infectan de forma cruzada los moldes de yeso. Se han descrito varios métodos de desinfección de impresiones en la literatura que tienen sus propias ventajas, desventajas y efectos sobre el material de impresión. Con el fin de mejorar el conocimiento y el comportamiento de los trabajadores de la salud dental con respecto a la desinfección de impresiones, en la presente revisión se sintetizan las técnicas de desinfección actuales así como sus efectos sobre la estabilidad dimensional y reproducción de detalles de los materiales de impresión. El uso de un desinfectante de nivel medio es recomendado por la Asociación Dental Americana, siendo los agentes químicos más accesibles que los agentes físicos por su fácil aplicación y menor costo. El desinfectante más recomendado es el hipoclorito de sodio al 5,25%, debido a sus mínimas interacciones, su bajo precio y, aunque la solución es poco estable, su renovación es fácil y económica.Impression taking in dentistry is a frequent performed procedure and its contamination by microorganisms present in the oral flora requires that it be subjected to a disinfection procedure after being removed from the mouth, to minimize the risks of cross infection both in the clinic as in the laboratory. Impressions can be a source of infections transmission between the dentist and the laboratory due to the contact with saliva and blood of the patient, which then cross-infect the plaster casts. Several methods of impressions disinfection had been described in the literature that has their own advantages, disadvantages and effects on the impression material. In order to improve the knowledge and behavior of dental health workers regarding the disinfection of impressions, the present review summarizes current disinfection techniques as well as their effects on dimensional stability and reproduction of details of impression materials: The use of a mid-level disinfectant is recommended by the American Dental Association, chemical agents being more accessible than physical agents because of their easy application and lower cost. The most recommended disinfectant is 5.25% sodium hypochlorite, due to the minimal interactions with impression materials, although the solution is not very stable, it is economical and easy to obtain

Instruments for assessing the risk of falls in acute hospitalized patients: a systematic review and meta-analysis

Background Falls are a serious problem for hospitalized patients, reducing the duration and quality of life. It is estimated that over 84% of all adverse events in hospitalized patients are related to falls. Some fall risk assessment tools have been developed and tested in environments other than those for which they were developed with serious validity discrepancies. The aim of this review is to determine the accuracy of instruments for detecting fall risk and predicting falls in acute hospitalized patients. Methods Systematic review and meta-analysis. Main databases, related websites and grey literature were searched. Two blinded reviewers evaluated title and abstracts of the selected articles and, if they met inclusion criteria, methodological quality was assessed in a new blinded process. Meta-analyses of diagnostic ORs (DOR) and likelihood (LH) coefficients were performed with the random effects method. Forest plots were calculated for sensitivity and specificity, DOR and LH. Additionally, summary ROC (SROC) curves were calculated for every analysis. Results Fourteen studies were selected for the review. The meta-analysis was performed with the Morse (MFS), STRATIFY and Hendrich II Fall Risk Model scales. The STRATIFY tool provided greater diagnostic validity, with a DOR value of 7.64 (4.86 - 12.00). A meta-regression was performed to assess the effect of average patient age over 65 years and the performance or otherwise of risk reassessments during the patient’s stay. The reassessment showed a significant reduction in the DOR on the MFS (rDOR 0.75, 95% CI: 0.64 - 0.89, p = 0.017). Conclusions The STRATIFY scale was found to be the best tool for assessing the risk of falls by hospitalized acutely-ill adults. However, the behaviour of these instruments varies considerably depending on the population and the environment, and so their operation should be tested prior to implementation. Further studies are needed to investigate the effect of the reassessment of these instruments with respect to hospitalized adult patients, and to consider the real compliance by healthcare personnel with procedures related to patient safety, and in particular concerning the prevention of falls