4,750 research outputs found

    Uso de Información de Geolocalización, Usuario y Temporal para la Monitorización de Desastres Naturales en Twitter

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    During emergency situation events it is important to acquire as much information about the event as possible, and social media sites like Twitter offer important real-time user contributed data. Typical Information Filtering techniques are keyword-based approaches or focused on co-occurrence with keywords. However, these approaches can miss relevant local information if messages do not contain an initially considered event-related keyword. Considering geolocation, user and temporal information within a pseudo-relevance feedback approach we can find event-related terminology but not co-occurring with initially considered keywords. Thus, taking into account the temporal aspect we can modify a query expansion function like Kullback-Leibler divergence in order to improve the Information Filtering process. Our proposed approaches have been evaluated in two Twitter datasets associated with real-world events, obtaining encouraging results.Cuando se producen eventos relacionados con situaciones de emergencia, es importante acceder a tanta información como sea posible relacionada con dicho evento. En este contexto algunas redes sociales como Twitter suponen un importante recurso de información en tiempo real. La técnicas clásicas de filtrado de información suelen centrarse en el análisis de coocurrencia de términos con el conjunto de palabras clave inicialmente consideradas. Sin embargo, estas aproximaciones pueden perder información, ya que no son capaces de recuperar información relevante que venga expresada con palabras que no coocurran con las palabras clave inicialmente usadas, y que expresan nuestra necesidad de información. Considerar información de geolocalización, usuario o temporal dentro de un enfoque de pseudo-relevance feedback, nos permite encontrar terminología relacionada con el evento, pero no coocurrente con las palabras clave inicialmente consideradas. Por otro lado, considerando el aspecto temporal se puede modificar una función de expansión de consultas como la divergencia de Kullback-Leibler con el fin de mejorar el filtrado de información en estas situaciones de emergencia. Nuestras propuestas se han evaluado en dos colecciones de eventos del mundo real obteniéndose resultados alentadores.This work has been part-funded by the Spanish Ministry of Science and Innovation (MED-RECORD Project, TIN2013-46616-C2-2-R) and by UNED Project (2012V/PUNED/0004). This research was also partially supported by the U.S. Army Research Laboratory under Cooperative Agreement No. W911NF-09-2-0053 (NS-CTA)

    (2,2′-Bipyridine-κ2 N,N′)iodido(pyrrol­idine-1-dithio­carboxyl­ato-κ2 S,S′)copper(II)

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    In the title compound, [Cu(C5H8NS2)I(C10H8N2)], the CuII ion is coordinated by one iodide ion, two N atoms of the bipyridine ligand and two S atoms from the pyrrolidine-1-dithio­carboxyl­ate ligand in a distorted square-pyramidal environment

    Comparing in-vivo confocal microscopy and ex-vivo light and scanning electron microscopy images of the hairs of the pine processionary caterpillar embedded in the cornea: Report of three cases

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    This report describes three cases of pine processionary caterpillar hairs (setae) embedded in the cornea: one in a 69‑year‑old man with acute keratouveitis, a second case in a 65‑year‑old man with an epithelial defect and a stromal infiltrate, and the third case affecting a 54‑year‑old woman with mild keratitis. The two first patients had one hair embedded in the anterior corneal layers while the last one had several hairs deeply embedded in the stroma. By comparing in‑vivo confocal microscopy (IVCM) with ex‑vivo light microscopy (LM) and scanning electron microscopy (SEM) images, the morphology of the setae was identified and confirmed.post-print2,18 M

    Magnetohydrodynamics dynamical relaxation of coronal magnetic fields. I. Parallel untwisted magnetic fields in 2D

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    Context. For the last thirty years, most of the studies on the relaxation of stressed magnetic fields in the solar environment have onlyconsidered the Lorentz force, neglecting plasma contributions, and therefore, limiting every equilibrium to that of a force-free field. Aims. Here we begin a study of the non-resistive evolution of finite beta plasmas and their relaxation to magnetohydrostatic states, where magnetic forces are balanced by plasma-pressure gradients, by using a simple 2D scenario involving a hydromagnetic disturbance to a uniform magnetic field. The final equilibrium state is predicted as a function of the initial disturbances, with aims to demonstrate what happens to the plasma during the relaxation process and to see what effects it has on the final equilibrium state. Methods. A set of numerical experiments are run using a full MHD code, with the relaxation driven by magnetoacoustic waves damped by viscous effects. The numerical results are compared with analytical calculations made within the linear regime, in which the whole process must remain adiabatic. Particular attention is paid to the thermodynamic behaviour of the plasma during the relaxation. Results. The analytical predictions for the final non force-free equilibrium depend only on the initial perturbations and the total pressure of the system. It is found that these predictions hold surprisingly well even for amplitudes of the perturbation far outside the linear regime. Conclusions. Including the effects of a finite plasma beta in relaxation experiments leads to significant differences from the force-free case

    Neurosymbolic AI for Reasoning on Graph Structures: A Survey

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    Neurosymbolic AI is an increasingly active area of research which aims to combine symbolic reasoning methods with deep learning to generate models with both high predictive performance and some degree of human-level comprehensibility. As knowledge graphs are becoming a popular way to represent heterogeneous and multi-relational data, methods for reasoning on graph structures have attempted to follow this neurosymbolic paradigm. Traditionally, such approaches have utilized either rule-based inference or generated representative numerical embeddings from which patterns could be extracted. However, several recent studies have attempted to bridge this dichotomy in ways that facilitate interpretability, maintain performance, and integrate expert knowledge. Within this article, we survey a breadth of methods that perform neurosymbolic reasoning tasks on graph structures. To better compare the various methods, we propose a novel taxonomy by which we can classify them. Specifically, we propose three major categories: (1) logically-informed embedding approaches, (2) embedding approaches with logical constraints, and (3) rule-learning approaches. Alongside the taxonomy, we provide a tabular overview of the approaches and links to their source code, if available, for more direct comparison. Finally, we discuss the applications on which these methods were primarily used and propose several prospective directions toward which this new field of research could evolve.Comment: 21 pages, 8 figures, 1 table, currently under review. Corresponding GitHub page here: https://github.com/NeSymGraph

    On the unusual gas composition in the Beta Pictoris debris disk

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    The metallic gas associated with the Beta Pic debris disk is not believed to be primordial, but arises from the destruction of dust grains. Recent observations have shown that carbon and oxygen in this gas are exceptionally overabundant compared to other elements, by some 400 times. We study the origin of this enrichment under two opposing hypothesis, preferential production, where the gas is produced with the observed unusual abundance (as may happen if gas is produced by photo-desorption from C/O-rich icy grains), and preferential depletion, where the gas evolves to the observed state from an original solar abundance (if outgassing occurs under high-speed collisions) under a number of dynamical processes. We include ... ... We find ... ...Comment: accepted to ApJ, revised text is highlighted in red color, the old figure 2 is removed, other figures are revise

    Mining Primary Care Electronic Health Records for Automatic Disease Phenotyping: A Transparent Machine Learning Framework

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    (1) Background: We aimed to develop a transparent machine-learning (ML) framework to automatically identify patients with a condition from electronic health records (EHRs) via a parsimonious set of features. (2) Methods: We linked multiple sources of EHRs, including 917,496,869 primary care records and 40,656,805 secondary care records and 694,954 records from specialist surgeries between 2002 and 2012, to generate a unique dataset. Then, we treated patient identification as a problem of text classification and proposed a transparent disease-phenotyping framework. This framework comprises a generation of patient representation, feature selection, and optimal phenotyping algorithm development to tackle the imbalanced nature of the data. This framework was extensively evaluated by identifying rheumatoid arthritis (RA) and ankylosing spondylitis (AS). (3) Results: Being applied to the linked dataset of 9657 patients with 1484 cases of rheumatoid arthritis (RA) and 204 cases of ankylosing spondylitis (AS), this framework achieved accuracy and positive predictive values of 86.19% and 88.46%, respectively, for RA and 99.23% and 97.75% for AS, comparable with expert knowledge-driven methods. (4) Conclusions: This framework could potentially be used as an efficient tool for identifying patients with a condition of interest from EHRs, helping clinicians in clinical decision-support process

    Efecto de la temperatura de termotratamiento en el comportamiento eléctrico de la madera de Pino radiata

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    En el presente trabajo se analiza el efecto de la temperatura del termotratamiento sobre la conductividad eléctrica de la madera de pino radiata. Sobre probetas de madera de pino radiata de procedencia País Vasco (España), termotratada a 190ºC y 210ºC por el método Thermowood así como sobre piezas testigo de la misma especie, procedencia y dimensiones, acondicionadas todas ellas hasta masa constante a 20ºC/40%HR, 20ºC/65%HR y 20ºC/90%HR se evaluó la resistencia eléctrica (longitudinal y transversal) y, posteriormente, se ajustó el modelo Samuelsson para modelizar en cada tipo de material la relación humedad de la madera-resistencia eléctrica. Se concluye que la temperatura empleada en el tratamiento térmico de la madera afecta no sólo a la humedad de equilibrio sino, también, a su conductividad eléctrica, siendo máximo este efecto en el tratamiento efectuado a 210ºC. AbstractThis paper analyzes the effect of heat treatment temperature on the electrical conductivity of radiata pine wood. On specimens of radiata pine of the Basque Country provenance (Spain), heat treated at 190°C and 210°C by the method Thermowood as well as not treated matched samples, conditioned up to constant mass at the standard conditions of 20°C/40%; 20°C/65% and 20°C/90% RH the electrical resistance (longitudinal and transverse) was measured and a Samuelsson model fitted to describe the relationship between the electrical resistance and moisture content of each material. From the data is concluded that the temperature employed in the thermal treatment timber not only affects equilibrium moisture content of wood but also to its electrical conductivity, being this effect  maximum in the processing performed at 210°C

    Thermographic imaging in sports and exercise medicine: A Delphi study and consensus statement on the measurement of human skin temperature

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    This is an accepted manuscript of an article published by Elsevier in Journal of Thermal Biology on 18/07/2017, available online: https://doi.org/10.1016/j.jtherbio.2017.07.006 The accepted version of the publication may differ from the final published version.© 2017 Elsevier Ltd The importance of using infrared thermography (IRT) to assess skin temperature (tsk) is increasing in clinical settings. Recently, its use has been increasing in sports and exercise medicine; however, no consensus guideline exists to address the methods for collecting data in such situations. The aim of this study was to develop a checklist for the collection of tsk using IRT in sports and exercise medicine. We carried out a Delphi study to set a checklist based on consensus agreement from leading experts in the field. Panelists (n  =  24) representing the areas of sport science (n = 8; 33%), physiology (n = 7; 29%), physiotherapy (n = 3; 13%) and medicine (n = 6; 25%), from 13 different countries completed the Delphi process. An initial list of 16 points was proposed which was rated and commented on by panelists in three rounds of anonymous surveys following a standard Delphi procedure. The panel reached consensus on 15 items which encompassed the participants’ demographic information, camera/room or environment setup and recording/analysis of tsk using IRT. The results of the Delphi produced the checklist entitled “Thermographic Imaging in Sports and Exercise Medicine (TISEM)” which is a proposal to standardize the collection and analysis of tsk data using IRT. It is intended that the TISEM can also be applied to evaluate bias in thermographic studies and to guide practitioners in the use of this technique.Published versio
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