2,643 research outputs found

    Dust correction factors over 0<z<30 < z < 3 in massive star-forming galaxies from stacking in \emph{Herschel}

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    In this work we use stacking analysis in \emph{Herschel} PACS to study the accuracy of several dust-correction factors typically employed to estimate total star-formation rate (SFR) of high-redshift star-forming (SF) galaxies. We also analyze what stacking suggests about the relation between SFR and stellar mass and the redshift evolution of the specific SFR (sSFR=SFR/M{\rm sSFR} = {\rm SFR} / {\rm M_*}). We find that the dust properties of massive SF galaxies evolve with redshift, being galaxies at z23z \sim 2-3 more attenuated than at z1z \sim 1 for a given UV continuum slope and stellar mass. As a consequence, a single IRX-β\beta relation can not be used to recover the total SFR of massive SF galaxies at 0z30 \lesssim z \lesssim 3. This might have implications for higher redshift studies, where a single IRX-β\beta relation derived for local starburst is usually assumed to be valid. However, we find that the local relation between dust attenuation and stellar mass is valid at least up to z1z \sim 1, although deviations are found for higher redshift galaxies where only log(M/M)>10.2510.50\log{\left( M_* / M_\odot \right)} > 10.25-10.50 galaxies are detected through stacking. This, therefore, does not rule out the possibility that the local dust-mass relation can be valid for less massive SF galaxies at z23z \sim 2-3. The SED fitting procedure with stellar population templates gives over-estimated values (about 0.3--0.5 dex in logSFR\log{\rm SFR}) of the dust-corrected SFR at all redshifts studied here. We find that the slope of the main-sequence of star formation is less steep than previously found in massive galaxies with log(M/M)10\log{\left( M_* / M_\odot \right)} \geq 10, and the redshift evolution of the sSFR reported in previous works in massive is well recovered.Comment: Accepted for publication in A&

    Presencia del cine en la educación musical en Educación Primaria

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    En el presente trabajo, en el que he tenido que realizar una investigación exhaustiva, analizaré las potencialidades del lenguaje cinematográfico como recurso audiovisual para la enseñanza de la Música en alumnos de seis a doce años. La comunicación audiovisual y los recursos tecnológicos van a estar presentes en casi todas las áreas en Educación Primaria, pero con más incidencia en unas que en otras. Esto no implica que no tengamos que trabajar con ellos estos aspectos desde pequeños, y es desde la Educación Primaria donde lo debemos de fomentar. La integración del cine en las aulas puede realizarse tanto por su vinculación en la vida cotidiana de los alumnos de estas edades, como por su papel con fines didácticos para la mejora de la comprensión, como documento de trabajo, centro de interés, motivación o refuerzo sobre un tema determinado, y también con fines educativos, donde veríamos su interés por la comunicación, trabajar el espíritu crítico, su conocimiento de la sociedad. Por último, las partes en las que consistirá el presente trabajo son: primero habrá una introducción, objetivos, justificación y vinculación del Trabajo de Fin de Grado con las competencias del título. A continuación, se realiza un marco teórico, eje principal del trabajo, donde se expondrán aquellos aspectos que hemos considerado importantes respecto al tema. Después, se trabaja una propuesta de intervención didáctica. Para finalizar, sacaremos unas conclusiones generales en torno al trabajo realizado.Grado en Educación Primari

    Coexistence of periods in a bisecting bifurcation

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    The inner structure of the attractor appearing when the Varley-Gradwell-Hassell population model bifurcates from regular to chaotic behaviour is studied. By algebraic and geometric arguments the coexistence of a continuum of neutrally stable limit cycles with different periods in the attractor is explained.Comment: 13 pages, 5 figure

    Families of piecewise linear maps with constant Lyapunov exponent

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    We consider families of piecewise linear maps in which the moduli of the two slopes take different values. In some parameter regions, despite the variations in the dynamics, the Lyapunov exponent and the topological entropy remain constant. We provide numerical evidence of this fact and we prove it analytically for some special cases. The mechanism is very different from that of the logistic map and we conjecture that the Lyapunov plateaus reflect arithmetic relations between the slopes.Comment: 26 pages, 13 figure

    Propuesta de intervención para el aprendizaje de EL2 en Educación Infantil

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    Este Trabajo Fin de Grado está basado en el estudio de una segunda lengua para alumnos extranjeros de Educación Infantil. La comunicación y el lenguaje son piezas fundamentales para la vida diaria, porque gracias a ellos, nos podemos comunicar de diferentes maneras, hablando, escribiendo o mediante lenguaje gestual. Con este trabajo buscamos conocer la historia de la comunicación desde los años 60 hasta la actualidad. Partiendo de este concepto, se detalla una propuesta didáctica que se desarrollará mediante una tarea final con niños que están estudiando una segunda lengua.Grado en Educación Infanti

    Rickettsia slovaca Infection: DEBONEL/TIBOLA

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    Producción CientíficaThis study describes the epidemiological, clinical, and microbiological characteristics of a new tick-borne disease in Spain—Dermacentor-borne necrosis erythema lymphadenopathy (DEBONEL). The clinical presentations include an eschar at the site of the tick bite, surrounded by an erythema and painful regional lymphadenopathy. The disease appears during the colder months and its vector is Dermacentor marginatus (D. marginatus). From January 1990 to December 2004, 54 patients presented at Hospital of La Rioja with these clinical and epidemiological data. The ratio of females to males was 32/22. The average age was 37 years. In all cases tick bites were located on the upper body (90% on the scalp). The median incubation period was 4.7 days. Signs and symptoms were mild in all cases. Only a small number of patients presented mild and nonspecific abnormalities in a complete blood cell count and mild elevation of erythrocyte sedimentation rates and C-protein reactive and liver enzyme levels. Serological evidence of acute rickettsiosis was observed in 19 patients (61%). In 29% sera tested by polymerase chain reactions (PCRs) were positive. The sequence obtained from a PCR product revealed 98% identity with Rickettsia sp. strains RpA4, DnS14, and DnS28. All ticks removed from patients were PCR-positive. Sequencing showed 8 of them identified as R. slovaca and 2 as Rickettsia sp. strains RpA4, DnS14, and DnS28

    Aportaciones a la taxonomía del género Asplenium: Anatomía del aparato productor de esporas.

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    Se ha realizado una descripción de la anatomía del aparato productor de esporas, y de los elementos que lo constituyen, en el género Asplenium, basada en el estudio de nueve especies, representativas de los subgéneros Pleurosorus y Asplenium, secciones Ceterach y Asplenium, greges trichomanes, adiantumnigrum, septentrionale y scolopendrium. En vista de la confusión terminológica que habitualmente se encuentra en los trabajos sobre anatomía de helechos, se presenta un glosario en el que se proponen las defmiciones más adecuadas extraídas de la literatura, así como algunas precisiones a éstas y términos nuevos, en base a nuestros resultados.A description of the anatomy of the sporeproducer mechanism, and the elements that form it in the genus Asplenium has been realized, based on the study of nine species representative, of the subgenera Pleurosorus andAsplenium, sections Ceterach andAsplenium, greges trichomanes, adiantum-nigrum, septentrionale and scolopendrium. . In sight of the terminological confusion that is usually found in works on fern anatomy, a glossary -taken out from literature- is presented, in wich adecuate explanations are proposed, along with some precissions to these and new terms, according to our results

    Back analysis of the coefficient of horizontal subgrade reaction from the monitored behaviour of diaphragm walls of Seville’s Underground

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    En este artículo se presenta un ábaco con los valores del coeficiente de balasto horizontal para el cálculo de pantallas en Sevilla. Dichos valores se han extrapolado a partir del comportamiento real en obra de las pantallas, medido con inclinómetros, durante las distintas fases de excavación. Se realiza de inicio un análisis primario utilizando los programas de cálculo Plaxis, Rido y Cype y los valores del coeficiente de balasto de Chadeisson. La comparación y discusión de los resultados obtenidos nos lleva a concluir que los cálculos habituales con Rido y Cype no son fiables para predecir adecuadamente el comportamiento real de las pantallas. Por eso se realiza un análisis paramétrico, variando los valores del coeficiente de balasto, hasta dar con aquéllos que mejor reproducen la realidad medida. Los resultados alcanzados se sintetizan en forma de ábaco para que lo aprendido con la experiencia pueda ser aplicado en futuros trabajos.This paper presents an abacus with the values of the coefficient of horizontal subgrade reaction for retaining wall analysis in Seville. The aforementioned values have been extrapolated from the actual behaviour on site of the retaining walls, monitored with inclinometers, during the different excavation stages. A primary analysis is carried out initially using the calculation programs Plaxis, Rido and Cype and Chadeisson values of the coefficient of horizontal subgrade reaction. The comparison and discussion of the achieved results leads us to conclude that the usual calculations with Rido and Cype are not reliable for accurately predicting the actual behaviour of the retaining walls. Due to that a parametric analysis is carried out, varying the values of the coefficient of horizontal subgrade reaction, until finding those which mach better the measured reality. The obtained results are synthesised in an abacus so that the knowledge learnt through experience can be applied in future works

    El insomnio

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    Insomnia is a common pathology in the general population. It is estimated that 10 to 15 percent of the adult population has chronic insomnia and 25 to 35 percent have suffered occasional or transient insomnia due to stressful situations. The aim of this article is to provide a review of insomnia: causes, differential diagnosis, and different options of treatment. To that end we have made a search in Pubmed with the keywords "insomnia", "sleeplessness", "sleep disorders" and "pharmacological therapy". Insomnia evaluation includes a careful sleep history, personal and family history of mental and organic illness, and a registration of drug and medication intake. Authors agree that treatment should be based primarily on etiology, and secondarily on symptomatology
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