An additional ageing criterion for Penduline Tits (Remiz pendulinus)

Els individus adults de teixidor realitzen una muda completa després de la cria, mentre que els ocells del primer any efectuen una muda estival parcial, després de la qual retenen algunes cobertores grans. Alguns autors han suggerit que una part dels ocells joves mudarien totes les cobertores grans, i que seria possible confondre'ls amb ocells adults. D'una mostra de 156 teixidors, 48 presentaren una muda completa de totes les cobertores grans i àlula (individus adults); 100 presentaven un nombre variable de cobertores grans retingudes i la ploma central de l'àlula no mudada (individus de primer any). Es suggereix que la ploma central de l'àlula és un criteri més fiable que la muda de les cobertores grans per determinar l'edat del teixidor en les poblacions més meridionals

Three-dimensional measurements with a novel technique combination of confocal and focus variation with a simultaneous scan

The most common optical measurement technologies used today for the three dimensional measurement of technical surfaces are Coherence Scanning Interferometry (CSI), Imaging Confocal Microscopy (IC), and Focus Variation (FV). Each one has its benefits and its drawbacks. FV will be the ideal technology for the measurement of those regions where the slopes are high and where the surface is very rough, while CSI and IC will provide better results for smoother and flatter surface regions. In this work we investigated the benefits and drawbacks of combining Interferometry, Confocal and focus variation to get better measurement of technical surfaces. We investigated a way of using Microdisplay Scanning type of Confocal Microscope to acquire on a simultaneous scan confocal and focus Variation information to reconstruct a three dimensional measurement. Several methods are presented to fuse the optical sectioning properties of both techniques as well as the topographical information. This work shows the benefit of this combination technique on several industrial samples where neither confocal nor focus variation is able to provide optimal results.Postprint (author's final draft

Digital resonance for MEMS

This work shows the application of Pulsed Digital Oscillators to the detection of physical changes in MEMS devices that cause small shifts in their resonance frequencies. Such devices can be used as resonators in several sensor applications. According to this, a case study using a PDO structure to measure small concentrations of volatile organic gas compounds (VOC’s) introduced here. The MEMS devices used are cantilevers with a thin layer of polymer sensitive to the VOC concentration. Such devices have been simulated with the Coventor software to see the influence of the polymer layers on their mechanical responses. Finally, experimental measurements with various VOCs have been done, and results extracted from two PDO system sources, digital and analog, have been analyzed and compared.Peer ReviewedPostprint (published version

Structural changes of Arthrospira sp. after low energy sonication treatment for microalgae harvesting: elucidating key parameters to detect the rupture of gas vesicles

© . This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/The buoyancy suppression by low energy sonication (LES) treatment (0.8 W·mL-1, 20 kHz, 10 s) has recently been proposed as an initial harvesting step for Arthrospira sp. This paper aims to describe the structural changes in Arthrospira sp. after LES treatment and to present how these structural changes affect the results obtained by different analytical techniques. Transmission electron microscopy (TEM) micrographs of trichomes evidenced the gas vesicles rupture but also revealed a rearrangement of thylakoids and more visible phycobilisomes were observed. Differences between treated and untreated samples were detected by confocal microscopy, flow cytometry and optical microscopy but not by electrical impedance spectroscopy (EIS). After LES treatment, 2-fold increase in autofluorescence at 610/660 nm was measured (phycocyanin/allophycocyanin emission wavelengths) and a ten-fold decrease in side scatter light intensity (due to a reduction of trichome’s inner complexity). This was further confirmed by optical microscopy showing changes on trichomes appearance (from wrinkled to smooth).Peer ReviewedPostprint (author's final draft

Use of wiris quizzes in an online calculus course

Calculus courses often present a large number of difficulties to undergraduate students of scientific studies, especially in engineering degrees. These difficulties are sometimes related to teaching and assessment strategies. In this paper, a teaching innovation experience is presented within the framework of the Universitat Oberta de Catalunya. This teaching experience is focused on a continuous assessment through a systematic use of the so-called WIRIS quizzes. Academic outcomes are very positive from both quantitative and qualitative viewpoints.Peer ReviewedPostprint (author's final draft

Use of wiris quizzes in an online calculus course

Calculus courses often present a large number of difficulties to undergraduate students of scientific studies, especially in engineering degrees. These difficulties are sometimes related to teaching and assessment strategies. In this paper, a teaching innovation experience is presented within the framework of the Universitat Oberta de Catalunya. This teaching experience is focused on a continuous assessment through a systematic use of the so-called WIRIS quizzes. Academic outcomes are very positive from both quantitative and qualitative viewpointsPeer Reviewe

Politizando la tragedia : Donald Trump frente al debate contemporáneo sobre la regulación de armas

El debat sobre la regulació d'armes ha sigut constant a la història dels Estats Units, particularment en els debats en relació al significat polític i legal de la 2a esmena. En concret, el debat ha pres protagonisme a l'escenari polític contemporani a causa del problema de salut pública que suposa actualment la violència armada al país. A aquest treball es teoritzen des de una perspectiva post-estructuralista les narratives contemporànies a favor dels drets a tenir armes i, en particular, s'analitzen les pràctiques discursives de Donald Trump respecte a la regulació d'armes. Mitjançant aquesta anàlisi es defensa que el discurs de Donald Trump s'ha d'entendre com a part de les narratives iniciades als anys 70 pels gun-right movements, i que aquest sedimenta la relació entre l'"americà mitjà" com a subjecte polític i els discursos dominants sobre la regulació d'armes.El debate sobre la regulación de armas ha sido constante en la historia de los Estados Unidos, particularmente en los debates en relación con el significado político y legal de la 2a enmienda. En concreto, el debate ha tomado protagonismo en el escenario político contemporáneo a causa del problema de salud pública que supone actualmente la violencia armada en el país. En este trabajo se teorizan desde una perspectiva post-estructuralista las narrativas contemporáneas en favor de los derechos a tener armas y, en particular, se analizan las prácticas discursivas de Donald Trump respecto a la regulación de armas. Mediante este análisis se defiende que el discurso de Donald Trump se debe entender como parte de las narrativas iniciadas en los 70s por los gun-right movements, y que este sedimenta la relación del "americano medio" como sujeto político y los discursos dominantes sobre la regulación de armas.The debate around gun control has been central to the history of the United States, specifically the debates around the legal and political meaning of the 2nd amendment. In particular, the debate has gained prominence on the current political landscape, as the issue of gun violence is becoming more of a threat to public health. In this study the contemporary narratives around gun-rights are theorised through a post-structuralist perspective. Moreover, this theoretical perspective is complemented with the analysis of the discursive practices of the elected president Donald Trump around this same matter. Through this analysis, it is concluded that Donald Trump's discourse has to be understood as part of the discourses started by the gun-right movements around the 70s. Furthermore, it is argued that this discourse goes alongside a process of discursive sedimentation that relates the political figure of the "law-abiding American" with the dominant discourses of the current debate

Wiris Quizzes: Un sistema de evaluación continua con feedback automático para el aprendizaje de matemáticas en línea

En estudios en línea de ingeniería, el seguimiento del proceso de aprendizaje de los estudiantes de matemáticas así como el sistema de evaluación son aspectos clave de la estrategia docente. En este artículo se presenta un sistema de evaluación continua con feedback automático, basado en la realización de cuestionarios Wiris Quizzes durante un curso de análisis matemático en la Universitat Oberta de Catalunya. Dichos cuestionarios, con enunciados parametrizados, funcionan en el entorno de Moodle con el soporte del programa de cálculo simbólico Wiris (www.wiris.com). Los resultados de la experiencia docente con esta metodología en una aula con 65 estudiantes y la comparación con los de semestres anteriores son claramente positivos: (a) el número de estudiantes que siguen la evaluación continua se mantiene estable; (b) la media de las notas de la evaluación continua aumenta de forma considerable; (c) el número de estudiantes que suspenden la asignatura se ha reducido significativamente y (d) la valoración que los estudiantes hacen de la asignatura, de sus contenidos y de los recursos que se ponen a su disposición ha mejorado notablemente.Postprint (published version

Integración de texto y vídeo en un nuevo recurso para el aprendizaje de matemáticas en línea

Las características especiales del aprendizaje en línea conllevan la necesidad de disponer de materiales adaptados. El feedback con los estudiantes denota que la notación matemática y los conocimientos previos son a menudo los grandes escollos a superar para la comprensión de la materia. Todo ello ha guiado nuestro esfuerzo por mejorar la calidad de la enseñanza que impartimos, buscando nuevos recursos educativos que ayuden a paliar los problemas detectados. En este documento se presenta la experiencia de la integración de texto y video en un recurso utilizado en asignaturas de Análisis Matemático. Justificamos su elección y detallamos su uso a lo largo de un semestre. Finalmente, hacemos un análisis estadístico de los datos disponibles, que nos lleva a la conclusión que existe una clara tendencia de mejora de los resultados académicos.Postprint (published version