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Extracción de ácido cítrico de disoluciones acuosas diluidas utilizando niosomas y microfiltración con membranas cerámicas
Get PDFEn este trabajo se evalúa la posibilidad de utilizar tecnologías limpias como son los procesos con membranas, para la extracción del ácido cítrico con niosomas y microfiltración de forma simultánea, utilizando una membrana cerámica tubular Filtanium (Tami) de microfiltración de TiO2 de 0,2 micras de tamaño de poro, con el fin de recuperel ácido cítrico presente en disoluciones acuosas diluidas a diferentes concentraciones y distintos volúmenes de fase dispersa de niosomas.This study evaluates the possibility of using clean technologies such as membranes for the extraction of citric acid using a combined niosome extraction-microfiltration process, using a tubular microfiltration TiO2 ceramic membrane Filtanium (Tami) of 0.2 microns of pore size, in order to recover the of citric acid present in dilute aqueous solutions at several concentrations and different volumes of the niosomes’ dispersed phase.Este trabajo ha sido realizado en el marco de los proyectos de investigación BU050P20 y BU301P18 (Valorización integral de subproductos de la industria agroalimentaria mediante tecnologías emergentes), financiados por la Junta de Castilla y León y el Fondo Europeo de Desarrollo Regiona
An Efficient Discrete Model to Approximate the Solutions of a Nonlinear Double-Fractional Two-Component Gross–Pitaevskii-Type System
Get PDFIn this work, we introduce and theoretically analyze a relatively simple numerical algorithm
to solve a double-fractional condensate model. The mathematical system is a generalization of
the famous Gross–Pitaevskii equation, which is a model consisting of two nonlinear complexvalued diffusive differential equations. The continuous model studied in this manuscript is a
multidimensional system that includes Riesz-type spatial fractional derivatives. We prove here the
relevant features of the numerical algorithm, and illustrative simulations will be shown to verify the
quadratic order of convergence in both the space and time variables.J.E.M.-D. thanks the National Council of Science and Technology of Mexico for financially supporting him via grant A1-S-45928. Ministerio de Ciencia e Innovación and Regional Development European Funds through project PGC2018-101443-B-I00
Transcultural Impact of Learning to Teach Sport Education on Preservice Teachers’ Perceived Teaching Competence, Autonomy, and Academic Motivation
Get PDFPurpose: To compare the impact of the experience of learning to teach sport education on preservice teachers’ (from Spain, Chile, and Mexico) perceived professional competence, autonomy, and academic motivation and to explore participants’ perceptions of their country’s sociocultural and curricular aspects that may influence sport education implementation. Method: Framed by the “pedagogy of dialogue” and a “living the curriculum” approach, three consecutive miniseasons on alternative invasion games were enacted (n = 30 lessons). A quasi-experimental pre- and posttest mixed-methods design was followed, with a total of 163 preservice teachers. The quantitative data on preservice teachers’ teaching competence, autonomy, and academic motivation were collected through three validated questionnaires. Focus group interviews and field notes were used to gather qualitative information. Results: The main quantitative analysis exposed no relevant differences among the transcultural sample of preservice teachers related to the analyzed variables. Qualitative analysis showed the power of contextual factors to filter preservice teachers’ understanding of the model. Conclusions: The dialogical nature of the approach and the miniseason structure allowed the preservice teachers to achieve a better understanding of the pedagogy of sport education and to optimize their motivation to use it in the future. The rigidity of the national curriculum and the custodial nature of school reality, however, present strong barriers to this end
How to avoid order reduction when Lawson methods integrate nonlinear initial boundary value problems
Get PDFIt is well known that Lawson methods suffer from a severe order reduction when integrating initial boundary value problems where the solutions are not periodic in space or do not satisfy enough conditions of annihilation on the boundary. However, in a previous paper, a modification of Lawson quadrature rules has been suggested so that no order reduction turns up when integrating linear problems subject to time-dependent boundary conditions. In this paper, we describe and thoroughly analyse a technique to avoid also order reduction when integrating nonlinear problems. This is very useful because, given any Runge–Kutta method of any classical order, a Lawson method can be constructed associated to it for which the order is conserved.This work was funded by Ministerio de Ciencia e Innovación and Regional Development European Funds through project PGC2018-101443-B-I00 and by Junta de Castilla y León and Feder through projects VA169P20
Influence of the functional class of the players in wheelchair basketball: a comparative match analysis
No full textWith the use of the observational methodology, a comparative match analysis has been carried out between the two finalist teams of the Paralympic Games in Rio de Janeiro 2016 -the observational sampling is made up of all the sequences finished in shooting in each of the matches played by the selections of USA and Spain-. The objective has been to characterize the way in which both teams resolve the issue of the functional class of their players and their influence on the construction of offensive sequences that end in a shot -effective and ineffective-. An adaptation (the introduction of the functional class handicap criterion) was performed on the observation instrument SOBL-2. Regarding the recording and coding process, the observation instrument has been introduced in the software LINCE. The reliability of the data has been guaranteed, in the form of interobserver agreement, by means of the Cohen's Kappa coefficient. The results of the analysis of the search for associative relationships between categorical variables indicate how both selections solve the question of the functional class of their players in different ways; the Spanish team shows a game pattern that is further away from the results reflected in the scientific literature and the US game can be considered more orthodox. The Tpatterns detected, using the THEME software (v.6 Edu), have made it possible to characterize sequences, effective and ineffective, common and differential in both teams, taking into account the functional class of the players who participate in the construction of the sequences that achieve a shot.The authors gratefully acknowledge the support of a Spanish government subproject Integration ways between qualitative and quantitative data, multiple case development, and synthesis review as main axis for an innovative future in physical activity and sports research [PGC2018-098742-B-C31] (2019-2021) (Ministerio de Ciencia, Innovación y Universidades / Agencia Estatal de Investigación / Fondo Europeo de Desarrollo Regional), that is part of the coordinated project New approach of research in physical activity and sport from mixed methods perspective (NARPAS_MM) [SPGC201800X098742CV0]. In addition, authors thanks the support of the Generalitat de Catalunya Research Group, GRUP DE RECERCA I INNOVACIÓ EN DISSENYS (GRID). Tecnología i aplicació multimedia i digital als dissenys observacionals [Grant number 2017 SGR 1405]. Also, this study was funded by grants from the University of La Rioja
Sequential analysis of the construction of shots in wheelchair basketball and efficiency by player classification level
No full textThe objective of the present study was to analyse the construction and effectiveness of the offensive sequences of shots by members of the 2016 Paralympic gold medal men’s wheelchair basketball team. The analysis included the shot situation and of the actions leading up to the shot (reception prior to the shot, last pass, reception prior to the last pass, penultimate pass, and previous reception to the penultimate pass), based on the classification level of the player who performs the technical-tactical action. The registration and coding of the data was performed on the software programme LINCE. The reliability of the data was examined by inter-observer agreement through Cohen's Kappa coefficient. The results allow to deepen the specificity of the game of this sport, having characterized the construction of effective and ineffective (shot from the right lateral or the centre; from the offensive outside or from the offensive intermediate zone; shot made by players with the greatest functional limitations; players with greater functional difficulties perform the last reception, the last pass, and the reception prior to the last pass) sequences.The authors gratefully acknowledge the support of a Spanish government subproject Integration ways between qualitative and quantitative data, multiple case development, and synthesis review as main axis for an innovative future in physical activity and sports research [PGC2018-098742-B-C31] (20192021) (Ministerio de Ciencia, Innovación y Universidades / Agencia Estatal de Investigación / Fondo Europeo de Desarrollo Regional), that is part of the coordinated project New approach of research in physical activity and sport from mixed methods perspective (NARPAS_MM) [SPGC201800X098742CV0]. In addition, authors thanks the support of the Generalitat de Catalunya Research Group, GRUP DE RECERCA I INNOVACIÓ EN DISSENYS (GRID). Tecnología i aplicació multimedia i digital als dissenys observacionals [Grant number 2017 SGR 1405]
Proyecto de investigación: la motivación del profesorado en Castilla y León
Get PDFTrabajo de la asignatura Innovación docente e iniciación a la investigación educativaEn este estudio se pretende recopilar y analizar los diferentes factores que influyen en la motivación y desmotivación de los docentes. Partimos de la hipótesis de que cuanto mayor sea el tiempo trabajado mayor será la desmotivación del docente. Se trata de un estudio no experimental y descriptivo en el cual participarán 300 profesores de secundaria. Se evaluarán su motivación, de forma cuantitativa a través de la escala Maslach Burnout Inventory Maslach, C. (1997) y de forma cualitativa a través de grupos de discusión. Con los datos obtenidos se plantearán investigaciones análogas a nivel nacional y se extraerán las posibles soluciones que podrían mejorar la experiencia docente.The aim of this paper is to compile and analyse the different elements and factors which influence the motivation and demotivation of teachers. We start from the hypothesis that the longer is their teaching career, the greater will be their demotivation. This is a non-experimental and descriptive study in which 300 secondary school teachers will participate. Their motivation will be evaluated quantitatively using the Maslach Burnout Inventory scale Maslach, C. (1997) and qualitatively through discussion groups. Using the data obtained, analogous nationwide research will be carried out as well as possible solutions will be identified in order to improve the teaching experience