21 research outputs found

    Optimizing polymer lab-on-chip platforms for ultrasonic manipulation: Influence of the substrate

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    The choice of substrate material in a chip that combines ultrasound with microfluidics for handling biological and synthetic microparticles can have a profound effect on the performance of the device. This is due to the high surface-to-volume ratio that exists within such small structures and acquires particular relevance in polymer-based resonators with 3D standing waves. This paper presents three chips developed to perform particle flow-through separation by ultrasound based on a polymeric SU-8 layer containing channelization over three different substrates: Polymethyl methacrylate (PMMA); Pyrex; and a cracked PMMA composite-like structure. Through direct observations of polystyrene microbeads inside the channel, the three checked chips exhibit their potential as disposable continuous concentration devices with different spatial pressure patterns at frequencies of resonance close to 1 Mhz. Chips with Pyrex and cracked PMMA substrates show restrictions on the number of pressure nodes established in the channel associated with the inhibition of 3D modes in the solid structure. The glass-substrate chip presents some advantages associated with lower energy requirements to collect particles. According to the results, the use of polymer-based chips with rigid substrates can be advantageous for applications that require short treatment times (clinical tests handling human samples) and low-cost fabrication. © 2015 by the authors; licensee MDPI, Basel, Switzerland.The study has been performed in the framework of two Spanish National Research Project BIO2011-30535-C04-01,02,03, “Development of a high throughput for isolation of tumor cells circulating in peripheral blood”.We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI).Peer Reviewe

    Innovación en las enseñanzas universitarias: experiencias presentadas en las III Jornadas de Innovación Educativa de la ULL

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    En este libro se recoge un conjunto de experiencias de innovación educativa desarrolladas en la ULL en el curso 2011-12. Se abordan distintos ámbitos y ramas del conocimiento, y ocupan temáticas variadas que han sido desarrolladas con rigor, y con un claro potencial para su extrapolación a efectos de la mejora educativa en el ámbito universitario. Esta publicación constituye una primera edición de una serie que irá recogiendo las experiencias de innovación educativa de la ULL. Este es un paso relevante para su impulso en nuestra institución, como lo es el de su vinculación con la investigación educativa, para potenciar su publicación en las revistas científicas en este ámbito cada vez más pujante y relevante para las universidades. Sobre todo representan el deseo y el compromiso del profesorado de la ULL para la mejora del proceso educativo mediante la investigación, la evaluación y la reflexión compartida de nuestras prácticas y planteamientos docentes

    In COVID-19 Health Messaging, Loss Framing Increases Anxiety with Little-to-No Concomitant Benefits: Experimental Evidence from 84 Countries

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    The COVID-19 pandemic (and its aftermath) highlights a critical need to communicate health information effectively to the global public. Given that subtle differences in information framing can have meaningful effects on behavior, behavioral science research highlights a pressing question: Is it more effective to frame COVID-19 health messages in terms of potential losses (e.g., "If you do not practice these steps, you can endanger yourself and others") or potential gains (e.g., "If you practice these steps, you can protect yourself and others")? Collecting data in 48 languages from 15,929 participants in 84 countries, we experimentally tested the effects of message framing on COVID-19-related judgments, intentions, and feelings. Loss- (vs. gain-) framed messages increased self-reported anxiety among participants cross-nationally with little-to-no impact on policy attitudes, behavioral intentions, or information seeking relevant to pandemic risks. These results were consistent across 84 countries, three variations of the message framing wording, and 560 data processing and analytic choices. Thus, results provide an empirical answer to a global communication question and highlight the emotional toll of loss-framed messages. Critically, this work demonstrates the importance of considering unintended affective consequences when evaluating nudge-style interventions

    A global experiment on motivating social distancing during the COVID-19 pandemic

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    Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges

    A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic.

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    The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world

    Prevalencia de enfermedad renal crónica en pacientes con diabetes mellitus e hipertensión arterial en el Hospital Escandón

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    Durante el periodo comprendido entre el 1 de agosto de 2014 y el 31 de julio de 2015 se llevó a cabo, en las instalaciones del Hospital Escandón I.A.P una revisión metódica de pacientes para tratar de identificar la principal causa de enfermedad renal crónica en la población atendida en el nosocomio..

    La Universidad de Burgos a la Catedral de Burgos en su VIII Centenario

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    La Universidad de Burgos se ha sumado a la celebración del VIII Centenario de la Catedral de Burgos con esta monografía sobre la investigación, la gestión y la difusión que, desde nuestra institución y hasta la fecha, se ha hecho en torno a dicha basílica. Así, se aúnan los testimonios científicos y/o personales de personal docente e investigador, de administración y servicios y de estudiantes y compendia la producción bibliográfica de quienes, a lo largo de la historia de la UBU, han contribuido al conocimiento de la seo. Todo ello es fruto de la participación voluntaria de quienes han querido contribuir a esta edición

    Flujos de capitales, choques externos y respuestas de política en países emergentes

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    Las crisis financieras recientes han incrementado de manera significativa la complejidad de la política económica. Hoy día es necesario estar preparado para enfrentar huracanes financieros que surgen de lugares inesperados y que se expanden alrededor del mundo como reguero de pólvora. Para peor, estas crisis producen un profundo desconcierto entre inversores y analistas —incluyendo al propio Fondo Monetario Internacional—. La presente obra contiene un conjunto importante de artículos de alto calibre profesional que se enfocan sobre los nuevos desafíos que enfrenta la política económica en estas circunstancias. Los artículos estudian las características de los flujos de capitales, tanto en su totalidad como en su composición (capital de cartera, inversión directa, etc.) y su interrelación con el mercado de commodities (café y petróleo, en particular). Esto se complementa con un estudio cuidadoso de las vulnerabilidades financieras y un detallado análisis del papel de todos estos factores en la economía colombiana. El libro se convierte en un verdadero pionero en esta literatura y debería transformarse en referencia obligada para todos aquellos que quieran entender los nuevos fenómenos y desarrollar herramientas para prevenir sus peores consecuencias o paliar sus costos en economías emergentes, como la colombiana

    VII Jornadas de Innovación Educativa de la Universidad de La Laguna: imaginar y comprender la innovación en la Universidad

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    The change of structure and process of the organizations of the current society has generated a great impact in the new way of working. Work teams coordination ensures that a team functions as a unitary whole; is identified as a key process to understand work team effectiveness. This paper presents a brief introduction of the recent research on Work teams in organizations and raises relevant issues about their implications for Pedagogy studies. This paper aims, first, to analyze the potential of team based organizations. And secondly, to examine the effects in pedagogy studies. Coordination is a process that involves the use of strategies and patterns of behavior aimed to integrate actions, knowledge and goals of interdependent members. The tasks have increased its difficulty, doing that individual resolution is very difficult or impossibleUniversidad de La Lagun

    The High-Altitude water cherenkov (HAWC) observatory in México: The primary detector

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    The High-Altitude Water Cherenkov (HAWC) observatory is a second-generation continuously operated, wide field-of-view, TeV gamma-ray observatory. The HAWC observatory and its analysis techniques build on experience of the Milagro experiment in using ground-based water Cherenkov detectors for gamma-ray astronomy. HAWC is located on the Sierra Negra volcano in México at an elevation of 4100 meters above sea level. The completed HAWC observatory principal detector (HAWC) consists of 300 closely spaced water Cherenkov detectors, each equipped with four photomultiplier tubes to provide timing and charge information to reconstruct the extensive air shower energy and arrival direction. The HAWC observatory has been optimized to observe transient and steady emission from sources of gamma rays within an energy range from several hundred GeV to several hundred TeV. However, most of the air showers detected are initiated by cosmic rays, allowing studies of cosmic rays also to be performed. This paper describes the characteristics of the HAWC main array and its hardware.UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Físic
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