1,232 research outputs found

    The 3s Rydberg state as a doorway state in the ultrafast dynamics of 1,1-difluoroethylene

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    The deactivation dynamics of 1,1-difluoroethylene after light excitation is studied within the surface hopping formalism in the presence of 3s and 3p Rydberg states using multi-state second order perturbation theory (MS-CASPT2). Due to the proximity of the Rydberg π-3s state with the ππ* state, the states are mixed favoring ultrafast exchange of population via a conical intersection that closely resembles the equilibrium structure. After excitation, it is found that the π-3s state acts as a doorway state, trapping the population and delaying internal conversion to the ππ* state, from which deactivation to the closed-shell ground state takes place. Besides the conical intersection between the π-3s and ππ* states, five additional conical intersections between the ππ* state and the ground state are found, indicating that after the system is excited, it stretches the C[double bond, length as m-dash]C bond before it twists and pyramidalizes at any of the carbon atoms, in the spirit of a hula-twist mechanism

    The IGN-E case: Integrating through a hidden ontology

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    National Geographic Institute of Spain (IGN-E) wanted to integrate its main information sources for building a common vocabulary reference and thus to manage the huge amount of information it held. The main problem of this integration is the great heterogeneity of data sources. The Ontology Engineering Group (OEG) is working with IGN-E to attain this objective in two phases: first, by creating automatically an ontology using the semantics of catalogues sections, and second, by discovering mappings automatically that can relate ontology concepts to database instances. So, these mappings are the instruments to break the syntactic, semantic and granularity heterogeneity gap. We have developed software for building a first ontology version and for discovering automatically mappings using techniques that take into account all types of heterogeneity. The ontology contains a set of extra-attributes which are identified in the building process. The ontology, called PhenomenOntology, will be reviewed by domain experts of IGN-E. The automatic mapping discovery will be also used for discovering new knowledge that will be added to the ontology. For increasing the usability and giving independence to different parts, the processes of each phase will be designed automatically and as upgradeable as possible

    GeoLinked Data. An application case / Un caso de aplicación

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    In this paper we present the process that has been followed for the development of an application that makes use of several heterogeneous Spanish public datasets that are related to three themes of INSPIRE Directive, specifically Administrative Units, Hydrography, and Statistical Units. Our application aims at analysing existing relations between the Spanish coastal area and different statistical variables such as population, unemployment, dwelling, industry, and building trade. Besides providing ethodological guidelines for the generation, publishing and exploitation of Linked Data from such datasets, we provide an important innovation with respect to other similar processes followed in other initiatives by dealing with the geometrical information of features

    Rivière or Fleuve? Modelling Multilinguality in the Hydrographical

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    The need for interoperability among geospatial resources in different natural languages evidences the difficulties to cope with domain representations highly dependent of the culture in which they have been conceived. In this paper we characterize the problem of representing cultural discrepancies in ontologies. We argue that such differences can be accounted for at the ontology terminological layer by means of external elaborated models of linguistic information associated to ontologies. With the aim of showing how external models can cater for cultural discrepancies, we compare two versions of an ontology of the hydrographical domain: hydrOntology. The first version makes use of the labeling system supported by RDF(S) and OWL to include multilingual linguistic information in the ontology. The second version relies on the Linguistic Information Repository model (LIR) to associate structured multilingual information to ontology concepts. In this paper we propose an extension to the LIR to better capture linguistic and cultural specificities within and across language

    Combinando Linked Data con servicios geoespaciales

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    La Web de Linked Data supone un nuevo paradigma que pretende explotar la Web como un espacio global de información. La aplicación de los principios de esta nueva Web a la información geoespacial superará la integración de información tradicional, logrando una articulación semántica de los datos que haga desaparecer los silos de datos presentes en las actuales Infraestructuras de Datos Espaciales. Ante esta propuesta, en este artículo se describe el trabajo desarrollado en el marco de un caso de uso utilizando una parte de los datos del SIGNA. En este caso de uso se ha llevado a cabo un proceso de generación y publicación de los mencionados datos conforme a los principios de Linked Data y estos se combinan con diversos servicios de la IDEE y CartoCiudad para explotar el componente geoespacial

    Robot computing for music visualization

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    © Springer Nature Switzerland AG 2019. This paper presents an algorithm design of Music Visualization on Robot (MVR) which could automatically link the flashlight, color, and emotion through music. We call this algorithm as MVR algorithm that composed by two analyses. First, we focus on Music Signal Analysis. Second, we focus on Music Sentiment Analysis. We integrate two analysis results and implement the MVR algorithm on a robot called Zenbo which is released from ASUS Company. We perform the Zenbo Robot in luminous environments. The MVR system not only could be used in Zenbo robot but also could extend to other fields of Artificial Intelligent (AI) equipment in the future

    Photocatalytic hydrogen production by biomimetic indium sulfide using Mimosa pudica leaves as template

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    Biomimetic sulfur-deficient indium sulfide (In2.77S4) was synthesized by a template-assisted hydrothermal method using leaves of Mimosa pudica as a template for the first time. The effect of this template in modifying the morphology of the semiconductor particles was determined by physicochemical characterization, revealing an increase in surface area, decrease in microsphere size and pore size and an increase in pore volume density in samples synthesized with the template. X-ray photoelectron spectroscopy (XPS) analysis showed the presence of organic sulfur (S O/S C/S H) and sulfur oxide species ( SO2, SO32−, SO42−) at the surface of the indium sulfide in samples synthesized with the template. Biomimetic indium sulfide also showed significant amounts of Fe introduced as a contaminant present on the Mimosa pudica leaves. The presence of these sulfur and iron species favors the photocatalytic activity for hydrogen production by their acting as a sacrificial reagent and promoting water oxidation on the surface of the templated particles, respectively. The photocatalytic hydrogen production rates over optimally-prepared biomimetic indium sulfide and indium sulfide synthesized without the organic template were 73 and 22 μmol g−1, respectively, indicating an improvement by a factor of three in the templated sample

    Mental health problems and resilience in adolescents during the COVID-19 pandemic in a post-armed conflict area in Colombia.

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    The impact of COVID-19 pandemic on mental health of adolescents are emerging and require particular attention in settings where challenges like armed conflict, poverty and internal displacement have previously affected their mental wellbeing. This study aimed to determine the prevalence of anxiety symptoms, depressive symptomatology, probable post-traumatic stress disorder and resilience in school-attending adolescents in a post-conflict area of Tolima, Colombia during the COVID-19. A cross-sectional study was carried out with 657 adolescents from 12 to 18 years old, recruited by convenience sampling in 8 public schools in the south of Tolima, Colombia, who completed a self-administered questionnaire. Mental health information was obtained through screening scales for anxiety symptoms (GAD-7), depressive symptomatology (PHQ-8), probable post-traumatic stress disorder (PCL-5) and resilience (CD-RISC-25). The prevalence observed for moderate to severe anxiety symptoms was 18.9% (95% CI 16.0-22.1) and for moderate to severe depressive symptomatology was 30.0% (95% CI 26.5-33.7). A prevalence of probable post-traumatic stress disorder (PTSD) of 22.3% (95% CI 18.1-27.2) was found. The CD-RISC-25 results for resilience had a median score of 54 [IQR 30]. These results suggest that approximately two-thirds of school-attending adolescents in this post-conflict area experienced at least one mental health problem such as anxiety symptoms, depressive symptomatology or probable PTSD during the COVID-19 pandemic. Future studies are of interest to establish the causal relationship between these findings and the impact of the pandemic. These findings highlight the challenge that schools have after pandemic to address the mental health of their students in order to promoting adequate coping strategies and implement prompt multidisciplinary interventions to reduce the burden of mental health problems in adolescents

    A Vanadium(III) Complex with Blue and NIR-II Spin-Flip Luminescence in Solution

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    Luminescence from Earth-abundant metal ions in solution at room temperature is a very challenging objective due to the intrinsically weak ligand field splitting of first-row transition metal ions, which leads to efficient nonradiative deactivation via metal-centered states. Only a handful of 3dn metal complexes (n ≠ 10) show sizable luminescence at room temperature. Luminescence in the near-infrared spectral region is even more difficult to achieve as further nonradiative pathways come into play. No Earth-abundant first-row transition metal complexes have displayed emission >1000 nm at room temperature in solution up to now. Here, we report the vanadium(III) complex mer-[V(ddpd)2][PF6]3 yielding phosphorescence around 1100 nm in valeronitrile glass at 77 K as well as at room temperature in acetonitrile with 1.8 × 10–4% quantum yield (ddpd = N,N′-dimethyl-N,N′-dipyridine-2-ylpyridine-2,6-diamine). In addition, mer-[V(ddpd)2][PF6]3 shows very strong blue fluorescence with 2% quantum yield in acetonitrile at room temperature. Our comprehensive study demonstrates that vanadium(III) complexes with d2 electron configuration constitute a new class of blue and NIR-II luminophores, which complement the classical established complexes of expensive precious metals and rare-earth elements
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