2,616 research outputs found

    The Adaptive Transient Hough method for long-duration gravitational wave transients

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    This paper describes a new semi-coherent method to search for transient gravitational waves of intermediate duration (hours to days). In order to search for newborn isolated neutron stars with their possibly very rapid spin-down, we model the frequency evolution as a power law. The search uses short Fourier transforms from the output of ground-based gravitational wave detectors and applies a weighted Hough transform, also taking into account the signal's amplitude evolution. We present the technical details for implementing the algorithm, its statistical properties, and a sensitivity estimate. A first example application of this method was in the search for GW170817 post-merger signals, and we verify the estimated sensitivity with simulated signals for this case.Comment: 13 pages, 14 figure

    Matched-filter study and energy budget suggest no detectable gravitational-wave 'extended emission' from GW170817

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    Van Putten & Della Valle (2018) have reported a possible detection of gravitational-wave 'extended emission' from a neutron star remnant of GW170817. Starting from the time-frequency evolution and total emitted energy of their reported candidate, we show that such an emission is not compatible with the current understanding of neutron stars. We explore the additional required physical assumptions to make a full waveform model, for example, taking the optimistic emission from a spining-down neutron star with fixed quadrupolar deformation, and study whether even an ideal single-template matched-filter analysis could detect an ideal, fully phase-coherent signal. We find that even in the most optimistic case an increase in energy and extreme parameters would be required for a confident detection with LIGO sensitivity as of 2018-08-17. The argument also holds for other waveform models following a similar time-frequency track and overall energy budget. Single-template matched filtering on the LIGO data around GW170817, and on data with added simulated signals, verifies the expected sensitivity scaling and the overall statistical expectation.Comment: 9 pages, 6 figures, updated version as accepted by MNRA

    Una aproximación a la percepción de los docentes sobre el aprendizaje cooperativo

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    XXI Jornades de Foment de la Investigació de la Facultat de Ciències Humanes i Socials (Any 2016)Según Johnson, Johnson y Holubec (1999), el aprendizaje cooperativo es el uso didáctico de grupos reducidos de alumnos y alumnas, de entre tres y cinco personas, para aprovechar al máximo su interacción con el fin de maximizar el aprendizaje de todos. El objetivo de este trabajo será documentarse sobre la información de que se dispone actualmente respecto a dicha estructura de trabajo y contrastarlo con la percepción que los docentes tienen de ella. Conocer la opinión de aquellos que hoy en día forman a los niños dentro de las aulas y la formación que reciben respecto al aprendizaje cooperativo. Para ello se cuenta con la colaboración de los tutores de educación primaria del CEIP Pío XII de Nules (Castellón), que han contestado a un cuestionario propuesto. En los resultados obtenidos se observa que la formación de los docentes respecto a este tema es casi inexistente si no se acercan a él por interés propio, y que hay puntos en los que su percepción coincide con lo escrito sobre el aprendizaje cooperativo y otros en los que no. Con este trabajo se realiza un acercamiento a la realidad de nuestras aulas y a la situación de nuestros docentes respecto a la estructura del aprendizaje cooperativo

    Baseline glucocorticoids are drivers of body mass gain in a diving seabird

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    Life-history trade-offs are influenced by variation in individual state, with individuals in better condition often completing life-history stages with greater success. Although resource accrual significantly impacts key life-history decisions such as the timing of reproduction, little is known about the underlying mechanisms driving resource accumulation. Baseline corticosterone (CORT, the primary avian glucocorticoid) mediates daily and seasonal energetics, responds to changes in food availability, and has been linked to foraging behavior, making it a strong potential driver of individual variation in resource accrual and deposition. Working with a captive colony of white-winged scoters (Melanitta fusca deglandi), we aimed to causally determine whether variation in baseline CORT drives individual body mass gains mediated through fattening rate (plasma triglycerides corrected for body mass). We implanted individuals with each of three treatment pellets to elevate CORT within a baseline range in a randomized order: control, low dose of CORT, high dose of CORT, then blood sampled and recorded body mass over a two-week period to track changes in baseline CORT, body mass, and fattening rates. The high CORT treatment significantly elevated levels of plasma hormone for a short period of time within the biologically relevant, baseline range for this species, but importantly did not inhibit the function of the HPA (hypothalamic-pituitary-adrenal) axis. Furthermore, an elevation in baseline CORT resulted in a consistent increase in body mass throughout the trial period compared to controls. This is some of the first empirical evidence demonstrating that elevations of baseline CORT within a biologically relevant range have a causal, direct, and positive influence on changes in body mass

    Baseline glucocorticoids are drivers of body mass gain in a diving seabird

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    Life‐history trade‐offs are influenced by variation in individual state, with individuals in better condition often completing life‐history stages with greater success. Although resource accrual significantly impacts key life‐history decisions such as the timing of reproduction, little is known about the underlying mechanisms driving resource accumulation. Baseline corticosterone (CORT, the primary avian glucocorticoid) mediates daily and seasonal energetics, responds to changes in food availability, and has been linked to foraging behavior, making it a strong potential driver of individual variation in resource accrual and deposition. Working with a captive colony of white‐winged scoters (Melanitta fusca deglandi), we aimed to causally determine whether variation in baseline CORT drives individual body mass gains mediated through fattening rate (plasma triglycerides corrected for body mass). We implanted individuals with each of three treatment pellets to elevate CORT within a baseline range in a randomized order: control, low dose of CORT, high dose of CORT, then blood sampled and recorded body mass over a two‐week period to track changes in baseline CORT, body mass, and fattening rates. The high CORT treatment significantly elevated levels of plasma hormone for a short period of time within the biologically relevant, baseline range for this species, but importantly did not inhibit the function of the HPA (hypothalamic–pituitary–adrenal) axis. Furthermore, an elevation in baseline CORT resulted in a consistent increase in body mass throughout the trial period compared to controls. This is some of the first empirical evidence demonstrating that elevations of baseline CORT within a biologically relevant range have a causal, direct, and positive influence on changes in body mass

    Cost Effectiveness and Budget Impact of Nivolumab Plus Ipilimumab Versus Platinum Plus Pemetrexed (with and Without Bevacizumab) in Patients with Unresectable Malignant Pleural Mesothelioma in Switzerland.

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    BACKGROUND Malignant pleural mesotheliomas (MPMs) are aggressive and often unresectable. In the past, chemotherapy was the standard for palliative treatment. However, immunotherapy with nivolumab+ipilimumab has recently received marketing approval. OBJECTIVES This study evaluated the cost effectiveness of nivolumab+ipilimumab versus pemetrexed+platinum (with/without bevacizumab) for Swiss patients with unresectable MPM, overall and by histological subtype. METHODS We developed a three-state Markov cohort model with a cycle length of 1 month, a 30-year time horizon, and a discount rate of 3% per year for costs and benefits. The model included the updated survival and treatment-dependent utility results from the Checkmate-743 and MAPS registration trials. A Swiss statutory health insurance perspective was considered with unit costs for 2022 from publicly available and real-world sources. We assumed a willingness-to-pay (WTP) threshold of CHF100,000/QALY. Model robustness was explored in sensitivity and scenario analyses. RESULTS Compared with chemotherapy, nivolumab+ipilimumab incurred additional costs of CHF109,115 and 0.57 additional quality-adjusted life-years (QALYs), yielding an incremental cost-effectiveness ratio (ICER) of CHF192,585/QALY (i.e. USD201,829/QALY) gained. Relative to their 2022 list price, nivolumab+ipilimumab may be cost effective if priced at 48% across all histologies. Assuming cisplatin-based instead of carboplatin-based chemotherapy reduced the ICER to CHF158,911/QALY (i.e. USD166,539/QALY). For the non-epithelioid subtype, nivolumab+ipilimumab was cost effective compared with chemotherapy (ICER of CHF97,894/QALY, i.e. USD102,593/QALY). Chemotherapy+bevacizumab was often a dominated strategy or would require a bevacizumab cost reduction to 28%. CONCLUSIONS Our model projected nivolumab+ipilimumab to be cost effective for the non-epithelioid subtype but not for all histologies. Substantial discounts for nivolumab+ipilimumab would be necessary to achieve cost effectiveness for all histologies

    kindaika shakai keiseishi no shutai joken : kaihatsu shugi shakai shokugyo shugi shakai

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    制度:新 ; 文部省報告番号:乙2136号 ; 学位の種類:博士(文学) ; 授与年月日:2008/2/5 ; 早大学位記番号:新4678早稲田大

    Multicopy Reinforcement Learning Agents

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    This paper examines a novel type of multi-agent problem, in which an agent makes multiple identical copies of itself in order to achieve a single agent task better or more efficiently. This strategy improves performance if the environment is noisy and the task is sometimes unachievable by a single agent copy. We propose a learning algorithm for this multicopy problem which takes advantage of the structure of the value function to efficiently learn how to balance the advantages and costs of adding additional copies

    El absentismo y la institución escolar

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    El artículo recoge, a modo de ejemplo, el pensamiento de un profesor y de varios alumnos absentistas, y describe cómo se sienten y cómo perciben el hecho de faltar a clase. Los ejemplos permiten evidenciar cierto desajuste de interpretaciones entre docentes y alumnado a partir de una misma situación. Y esta divergencia conduce a una cuestión fundamental: ¿quién o qué la genera
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