3,309 research outputs found

    Properties of polypyrrole polyvinilsulfate films for dual actuator sensing systems

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    One of the challenges of modern science is the development of actuators able to sense working conditions while actuation, mimicking the way in which biological organs work. Actuation of those organs includes nervous (electric) pulses dense reactive gels, chemical reactions exchange of ions and solvent. For that purpose, conducting polymers are being widely studied. In this work the properties of self-supported films of the polypyrrole:polyvinilsulfate (PPy/PVS) blend polymer were assessed. X-ray photoelectron spectroscopy (XPS) studies show how during reduction / oxidation the polymer exchanges cations when immersed in a NaClO4 aqueous solution, revealing free positive charges in the electrolytic solution as the driving agents leading to the swelling/shrinking of the polymer. Eventually it is the phenomenon responsible of the actuation of the polymeric motors. Submitting the system to consecutive potential sweeps shows the reaction is really sensing the scan rate used in each cycle revealing that while actuating the system is actually sensing the electrochemical working conditions.The research was supported by European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 641822

    PVT-Robust CMOS Programmable Chaotic Oscillator: Synchronization of Two 7-Scroll Attractors

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    Designing chaotic oscillators using complementary metal-oxide-semiconductor (CMOS) integrated circuit technology for generating multi-scroll attractors has been a challenge. That way, we introduce a current-mode piecewise-linear (PWL) function based on CMOS cells that allow programmable generation of 2–7-scroll chaotic attractors. The mathematical model of the chaotic oscillator designed herein has four coefficients and a PWL function, which can be varied to provide a high value of the maximum Lyapunov exponent. The coefficients are implemented electronically by designing operational transconductance amplifiers that allow programmability of their transconductances. Design simulations of the chaotic oscillator are provided for the 0.35μ m CMOS technology. Post-layout and process–voltage–temperature (PVT) variation simulations demonstrate robustness of the multi-scroll chaotic attractors. Finally, we highlight the synchronization of two seven-scroll attractors in a master–slave topology by generalized Hamiltonian forms and observer approach. Simulation results show that the synchronized CMOS chaotic oscillators are robust to PVT variations and are suitable for chaotic secure communication applications.Universidad Autónoma de Tlaxcala CACyPI-UATx-2017Program to Strengthen Quality in Educational Institutions C/PFCE-2016-29MSU0013Y-07-23National Council for Science and Technology 237991 22284

    Dual sensing-actuation artificial muscle based on polypyrrole-carbon nanotube composite

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    Dual sensing artificial muscles based on conducting polymer are faradaic motors driven by electrochemical reactions, which announce the development of proprioceptive devices. The applicability of different composites has been investigated with the aim to improve the performance. Addition of carbon nanotubes may reduce irreversible reactions. We present the testing of a dual sensing artificial muscle based on a conducting polymer and carbon nanotubes composite. Large bending motions (up to 127 degrees) in aqueous solution and simultaneously sensing abilities of the operation conditions are recorded. The sensing and actuation equations are derived for incorporation into a control system.The research was supported by European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 641822

    ¿Antifascismo o ferrerada?: la izquierda francesa y el octubre español de 1934

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    Este artículo, parte de un estudio más amplio sobre el antifascismo de los años 1930, analiza la repercusión de la insurrección española de octubre de 1934 en Francia desde una perspectiva fronteriza entre la historia cultural de la política y la historia de la acción colectiva. Describe la movilización de la izquierda francesa en defensa de los insurrectos en sus aspectos políticos, sociales y discursivos, subrayando sus continuidades con episodios anteriores como el caso Ferrer de 1909 y las especificidades del incipiente movimiento antifascista que protagonizó la protesta (y que ésta contribuyó a su vez a construir). Se basa en fuentes hemerográficas y en documentación extraída de archivos españoles (AGA, Fundación Pablo Iglesias) y franceses (Archivos de la Prefectura de Policía de París, Archivos de la Ligue des Droits de l’Homme), ofreciendo un punto de vista original sobre la organización y las actividades de los principales comités implicados en el movimiento: en particular el Groupe des amis de l’Espagne y el Comité populaire d’aide à toutes les victimes du fascisme en Espagne.Cet article qui s’inscrit dans le cadre d’une étude sur l’antifascisme des années 1930, analyse la répercussion de l’insurrection espagnole d’octobre 1934 en France, depuis une perspective croisée entre l’histoire culturelle de la politique et l’histoire de l’action collective. Il décrit la mobilisation de la gauche française pour défendre les insurgés en soulignant les continuités avec les épisodes passés, comme le cas Ferrer de 1909, et les spécificités du mouvement antifasciste naissant, pilier du mouvement protestataire. Il se fonde sur la presse et des archives espagnoles et françaises offrant un point de vue original sur l’organisation et les activités des principaux comités impliqués dans le mouvement : le Groupe des amis de l’Espagne et le Comité populaire d’aide à toutes les victimes du fascisme en Espagne.This article, which is based on a broader study of 1930s anti-fascism, analyses the impact in France of the insurrection in Spain in 1934, from a standpoint somewhere between a cultural history of politics and a history of collective action. It recounts the political, social and discursive aspects of the mobilisation of the French left in defence of the insurgents, highlighting continuities from earlier events like the Ferrer case of 1909 and the particularities of the nascent anti-fascist movement which led the protest (and which this helped to build). It draws on newspaper records and on documentation from archives in Spain (AGA, Fundación Pablo Iglesias) and France (Archivos de la Prefectura de Policía de París, Archivos de la Ligue des Droits de l’Homme) to present a fresh view of the organisation and activities of the principal committees involved in the movement—particularly the Groupe des amis de l’Espagne y el Comité populaire d’aide à toutes les victimes du fascisme en Espagne

    De Masterman a Orwell: el debate británico sobre la propaganda en democracia, 1914-1945

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    Ellul, Chomsky y Keane, entre otros autores, han señalado la contradicción entre el principio liberal de libertad de prensa y la tendencia de las democracias contemporáneas a manipular la información para legitimarse y fabricar consensos. Este artículo busca el origen de esta situación en los debates sobre la propaganda de Estado que se desarrollaron en el Reino Unido durante y entre las dos guerras mundiales (1914-1945). Este episodio no se ha estudiado de manera monográfica, pese a afectar a un régimen pionero tanto en la historia del liberalismo como en el campo de la comunicación política. Más allá de su influencia en las decisiones de sus Gobiernos, las reflexiones de los intelectuales, altos cargos y profesionales de la comunicación británicos reflejan la ambivalencia con que la opinión del país aceptó la idea de una propaganda democrática, a la vez que iluminan conceptos clave de la cultura política liberal como la democracia, el totalitarismo, la nación, la cultura y la sociedad de masas.Ellul, Chomsky i Keane, entre altres autors, han assenyalat la contradicció entre el principi liberal de llibertat de premsa i la tendència de les democràcies contemporànies a manipular la informació per legitimar-se i fabricar consensos. Aquest article busca l'origen d'aquesta situació als debats sobre la propaganda d'Estat que es van desenvolupar al Regne Unit durant i entre les dues guerres mundials (1914-1945). Aquest episodi no s'ha estudiat de manera monogràfica, tot i que afectà un règim pioner tant en la història del liberalisme com en el camp de la comunicació política. Més enllà de la seva influència en les decisions dels seus Governs, les reflexions dels intel·lectuals, alts càrrecs i professionals de la comunicació britànics reflecteixen l'ambivalència amb que l'opinió del país va acceptar la idea d'una propaganda democràtica, alhora que il·luminen conceptes clau de la cultura política liberal com ara la democràcia, el totalitarisme, la nació, la cultura i la societat de masses.Ellul, Chomsky and Keane, among other authors, have observed the contradiction between the liberal principle of press freedom and the tendency of modern democracies to manipulate public opinion in order to gain legitimacy and manufacture consent. This article seeks the origins of this situation in the debates over political propaganda that took place in the United Kingdom during and between the two world wars (1914-1945). This episode has not been studied in depth, even though it affects a regime that played a pioneering role in the history of both liberalism and modern political communication. Beyond their direct influence on government decisions, the reflections of British intellectuals, public servants and experts reflect their ambivalent acceptance of the need for a democratic propaganda, while simultaneously illuminating such key concepts of liberal political culture as democracy, totalitarianism, national identity and the mass society

    Construir el acontecimiento a través de conceptos ordenadores

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    La motivación de este artículo es invitar a reflexionar sobre las prácticas específicas que implican el trabajo de campo en las ciencias sociales en general y en la teoría de las organizaciones, en particular. El objetivo a desarrollar es explicitar algunas reflexiones que, aparentemente, se sitúan a contracorriente de las prácticas de investigación que llevan a cabo algunos investigadores sociales y, simultáneamente, tratar de recobrar las discusiones y ciertas tendencias dominantes de las cátedras de Epistemología y Metodología de la Investigación.Fil: Fernández, Hugo Oscar. Universidad Nacional de Mar del Plata. Facultad de Ciencias Económicas y Sociales; Argentina

    Spectral type, temperature and evolutionary stage in cool supergiants

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    In recent years, temperature scales in cool supergiants (CSGs) have been disputed, and the possibility that spectral types (SpTs) do not depend primarily on temperature has been raised. We explore the relations between different observed parameters and the capability of deriving accurate intrinsic stellar parameters from them through the analysis of the largest spectroscopic sample of CSGs to date from SMC and LMC. We explore possible correlations between different observational parameters, also making use of near- and mid-infrared colours and literature on photometric variability. Direct comparison between the behaviour of atomic lines (Fe I, Ti I, and Ca II) in the observed spectra and synthetic atmospheric models provides compelling evidence that effective temperature is the prime underlying variable driving the SpT sequence in CSGs. However, there is a clear correlation between SpT and luminosity, with later ones tending to correspond to more luminous stars with heavier mass loss. The population of CSGs in the SMC is characterised by a higher degree of spectral variability, early spectral types (centred on type K1) and low mass-loss rates (at least as measured by dust-sensitive mid-infrared colours). The population in the LMC displays less spectroscopic variability and later spectral types. The distribution of spectral types is not single-peaked. Instead, the brightest CSGs have a significantly different distribution from less luminous objects, presenting mostly M subtypes (centred on M2), and increasing mass-loss rates for later types. In conclusion, the observed properties of CSGs in the SMC and the LMC cannot be described correctly by standard evolutionary models. The very strong correlation between spectral type and bolometric luminosity, supported by all data from the Milky Way, cannot be reproduced at all by current evolutionary tracks.Comment: 25 pages, 24 figure

    Great ideas in the world: a reality. Tensions in the modern single family houses, Osorno, Chile

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    The research deals with the theoretical notion of modernity that focuses on local views, one that addresses the ways in which each locality comes to build its own version of modernity, focusing, from architecture, in modern single family houses in the town of Osorno, Chile, seen as a reflection theme built on the articulation of the particular, the reality of the town, related to global modernization processes. We hypothesize that this joint modulates the expression of the architecture of Osorno single family houses, which has amalgamated local and universal signs, developed in tension between tradition and modernity. This approach, seeking to investigate the sources of these tensions, can explore a path of study of distinctive built expressions of local cultural practices and traditions in the twentieth centuryLa investigación indaga en la noción teórica de la modernidad que centra en las miradas locales aquella que atiende a las formas en que cada localidad acude para construir su versión de la modernidad enfocando, desde la arquitectura, en la vivienda unifamiliar moderna de la localidad de Osorno, Chile —temática observada como un reflejo construido de la articulación de lo particular—, la propia realidad de la localidad, conexa a los procesos modernizadores globales. Se analizaron autores que han tratado el desarrollo de la arquitectura latinoamericana en el contexto de la modernidad arquitectónica. Mediante método exploratorio-descriptivo se analizó una muestra intencionada de vivienda unifamiliar en Osorno, en la que se indagó respecto de su concepción en sintonía con parámetros de respuesta “local”, “en tensión” o “universal”. Se observó que la vivienda unifamiliar moderna de Osorno ha amalgamado señas locales con otras universales, desarrollándose en tensión entre tradición y modernidad

    RUbioSeq+: A multiplatform application that executes parallelized pipelines to analyse next-generation sequencing data

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    This is the peer reviewed version of the following article: Computer Methods and Programs in Biomedine 138 (2016): 73-81, which has been published in final form at http://dx.doi.org/10.1016/j.cmpb.2016.10.008Background and objective To facilitate routine analysis and to improve the reproducibility of the results, next-generation sequencing (NGS) analysis requires intuitive, efficient and integrated data processing pipelines. Methods We have selected well-established software to construct a suite of automated and parallelized workflows to analyse NGS data for DNA-seq (single-nucleotide variants (SNVs) and indels), CNA-seq, bisulfite-seq and ChIP-seq experiments. Results Here, we present RUbioSeq+, an updated and extended version of RUbioSeq, a multiplatform application that incorporates a suite of automated and parallelized workflows to analyse NGS data. This new version includes: (i) an interactive graphical user interface (GUI) that facilitates its use by both biomedical researchers and bioinformaticians, (ii) a new pipeline for ChIP-seq experiments, (iii) pair-wise comparisons (case–control analyses) for DNA-seq experiments, (iv) and improvements in the parallelized and multithreaded execution options. Results generated by our software have been experimentally validated and accepted for publication. Conclusions RUbioSeq+ is free and open to all users at http://rubioseq.bioinfo.cnio.es/.M.R-C is funded by the BLUEPRINT Consortium (FP7/ 2007-2013) under grant agreement number 282510. J.M.F is funded by the INB Node 2 - CNIO, a member of Proteored - PRB2-ISCIII and is supported by grant PT13/0001, of the PE I+D+i 2013-2016, funded by ISCIII and FEDER. H.L-F is funded by a postdoctoral fellowship from the Xunta de Galicia. F.F-R and D.G-P are funded by the European Union's Seventh Framework Programme FP7/REGPOT 2012 2013.1 under grant agreement n° 316265 (BIOCAPS) and the "Platform of integration of intelligent techniques for analysis of biomedical information" project (TIN2013-47153-C3-3-R) financed by the Spanish Ministry of Economy and Competitiveness C.FT is funded by the "Spanish National Youth Guarantee Implementation Plan” (2013/2016) financed by the Spanish Ministry of Economy and Competitivenes

    Ingesta de gomas elásticas en Garcillas Bueyeras (Bubulcus ibis)

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    L'anàlisi de nombroses egagròpiles recollides en un dormider d'esplugabous proper a l'abocador de Badajoz i diverses observacions directes d'individus menjant en aquesta zona indiquen que l'espècie ingireix gran quantitat de gomes. Això s'interpreta per la similaritat entre les gomes i els cucs de terra
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