1,953 research outputs found

    Four related benzazepine derivatives in a reaction pathway leading to a benzazepine carboxylic acid : hydrogen-bonded assembly in zero, one, two and three dimensions

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    The authors thank ‘Centro de Instrumentacion Cientıfico-Tecnica of Universidad de Jaen’ and the staff for data collection. AP, SAG and CMS thank Colciencias for financial support (grant No. 1102–521–28229). JC thanks the Consejerıa de Innovacion, Ciencia y Empresa (Junta de Andalucıa, Spain) and the Universidad de Jaen for financial support.(2R*,4S*)-Methyl 2,3,4,5-tetra­hydro-1,4-ep­oxy-1H-benz[b]azepine-2-carboxyl­ate, C12H13NO3, (I), and its reduction product (2R*,4S*)-methyl 4-hy­droxy-2,3,4,5-tetra­hydro-1H-benz[b]azepine-2-carboxyl­ate, C12H15NO3, (II), both crystallize as single enanti­omers in the space group P212121, while the hydrolysis product (2RS,4SR)-4-hy­droxy-2,3,4,5-tetra­hydro-1H-benz[b]azepine-2-carb­oxy­lic acid, C11H13NO3, (III), and the lactone (2RS,5SR)-8-(trifluoromethoxy)-5,6-dihydro-1H-2,5-methanobenz[e][1,4]oxazocin-3(2H)-one, C12H10F3NO3, (IV), both crystallize as racemic mixtures in the space group P21/c. The mol­ecules of compound (IV) are linked into centrosymmetric R22(10) dimers by N-HO hydrogen bonds, and those of compound (I) are linked into chains by C-H(arene) hydrogen bonds. A combination of O-HO and O-HN hydrogen bonds links the mol­ecules of com­pound (III) into sheets containing equal numbers of R44(14) and R44(26) rings, and a combination of C-H(arene) hydrogen bonds and three-centre O-H(N,O) hydrogen bonds links the mol­ecules of compound (II) into a three-dimensional frame­work structure. Comparisons are made with some related compounds.Publisher PDFPeer reviewe

    Dealing with Qualitative and Quantitative Features in Legal Domains

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    In this work, we enrich a formalism for argumentation by including a formal characterization of features related to the knowledge, in order to capture proper reasoning in legal domains. We add meta-data information to the arguments in the form of labels representing quantitative and qualitative data about them. These labels are propagated through an argumentative graph according to the relations of support, conflict, and aggregation between arguments.Comment: arXiv admin note: text overlap with arXiv:1903.0186

    Spatial deconvolution of spectropolarimetric data: an application to quiet Sun magnetic elements

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    Observations of the Sun from the Earth are always limited by the presence of the atmosphere, which strongly disturbs the images. A solution to this problem is to place the telescopes in space satellites, which produce observations without any (or limited) atmospheric aberrations. However, even though the images from space are not affected by atmospheric seeing, the optical properties of the instruments still limit the observations. In the case of diffraction limited observations, the PSF establishes the maximum allowed spatial resolution, defined as the distance between two nearby structures that can be properly distinguished. In addition, the shape of the PSF induce a dispersion of the light from different parts of the image, leading to what is commonly termed as stray light or dispersed light. This effect produces that light observed in a spatial location at the focal plane is a combination of the light emitted in the object at relatively distant spatial locations. We aim to correct the effect produced by the telescope's PSF using a deconvolution method, and we decided to apply the code on Hinode/SP quiet Sun observations. We analyze the validity of the deconvolution process with noisy data and we infer the physical properties of quiet Sun magnetic elements after the deconvolution process.Comment: 14 pages, 9 figure

    Detection of emission in the Si i 1082.7 nm line core in sunspot umbrae

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    We analyze spectropolarimetric sunspot umbra observations taken in the near-infrared Si i 1082.7 nm line taking NLTE effects into account. The data were obtained with the GRIS instrument installed at the German GREGOR telescope. A point spread function (PSF) was constructed using prior Mercury observations with GRIS and the information provided by the adaptive optics system of the GREGOR telescope. The data were then deconvolved from the PSF using a principal component analysis deconvolution method and were analyzed via the NICOLE inversion code. The Si i 1082.7 nm line seems to be in emission in the umbra of the observed sunspot after the effects of scattered light are removed. We show how the spectral line shape of umbral profiles changes dramatically with the amount of scattered light. Indeed, the continuum levels range, on average, from 44% of the quiet Sun continuum intensity to about 20%. The inferred levels are in line with current model predictions and empirical umbral models. Current umbral empirical models are not able to reproduce the emission in the deconvolved umbral Stokes profiles. The results of the NLTE inversions suggests that to obtain the emission in the Si i 1082.7 nm line, the temperature stratification should first have a hump located at about log tau -2 and start rising at lower heights when moving into the transition region. This is, to our knowledge, the first time the Si i 1082.7 nm line is seen in emission in sunspot umbrae. The results show that the temperature stratification of current umbral models may be more complex than expected with the transition region located at lower heights above sunspot umbrae. Our finding might provide insights into understanding why the sunspot umbra emission in the millimeter spectral range is less than that predicted by current empirical umbral models

    Anisakis infection in allis shad, Alosa alosa (Linnaeus, 1758), and twaite shad, Alosa fallax (Lacépède, 1803), from Western Iberian Peninsula Rivers : zoonotic and ecological implications

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    Acknowledgments The authors would like to thank M. N. Cueto and J.M. Antonio (ECOBIOMAR) for their excellent technical support and also Rodrigo López for making the map of the study area. We also thank the personal of the Vigo IEO, for providing information about shad captures at sea collected on the basis of national program (AMDES) included in the European Data Collection Framework (DCF) project. We are also grateful to Comandancia Naval de Tui for providing fishing data. M. Bao is supported by a PhD grant from the University of Aberdeen and also by financial support of the contract from the EU Project PARASITE (grant number 312068). This study was partially supported by a PhD grant from the Portuguese Foundation for Science and Technology (FCT) SFRH/BD/44892/2008) and partially supported by the European Regional Development Fund (ERDF) through the COMPETE—Operational Competitiveness Programme and national funds through Foundation for Science and Technology (FCT), under the project BPEst-C/MAR/ LA0015/2013. The authors thank the staff of the Station of Hydrobiology of the USC BEncoro do Con^ due their participation in the surveys. This work has been partially supported by the project 10PXIB2111059PR of the Xunta de Galicia and the project MIGRANET of the Interreg IV BSUDOE (South-West Europe) Territorial Cooperation Programme (SOE2/P2/E288). D.J. Nachón is supported by a PhD grant from the Xunta de Galicia (PRE/2011/198)Peer reviewedPostprin

    Two-point theory for the differential self-interrogation Feynman-alpha method

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    A Feynman-alpha formula has been derived in a two region domain pertaining the stochastic differential self-interrogation (DDSI) method and the differential die-away method (DDAA). Monte Carlo simulations have been used to assess the applicability of the variance to mean through determination of the physical reaction intensities of the physical processes in the two domains. More specifically, the branching processes of the neutrons in the two regions are described by the Chapman - Kolmogorov equation, including all reaction intensities for the various processes, that is used to derive a variance to mean relation for the process. The applicability of the Feynman-alpha or variance to mean formulae are assessed in DDSI and DDAA of spent fuel configurations.Comment: 15 pages, 5 figures. Submitted to EPJ Plu

    Influencia del complejo de embalses Mequinenza-Ribarroja-Flix (Río Ebro) en la morfología del cauce situado aguas abajo

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    Cuando se construye un embalse, el cauce que se sitúa aguas abajo de la presa suele sufrir alteraciones de diversa índole fundamentalmente porque se modifican las características de su caudal líquido y sólido. En este trabajo se analiza el tipo de alteraciones que se han dado en el río Ebro a lo largo de un tramo de aproximadamente 40 km de longitud que se localiza aguas abajo del complejo de embalses de Mequinenza-Ribarroja-Flix. Las principales alteraciones reconocidas son: ausencia de sedimentación, degradación de barras en los puntos más próximos a la presa, revegetación de barras y orillas, y pérdida de sedimentos finos con el consiguiente acorazamiento del lecho y de las barras. Dos factores han propiciado tales modificaciones, que han conducido prácticamente a la estabilidad del cauce, son la presencia de abundantes gravas y una elevada tasa de asentamiento vegetal en la sección. Asimismo se analiza la evolución morfosedimentaria del río desde 1927 hasta la fecha de construcción de estos embalses, años sesenta, y se determina que dicha evolución estaba controlada por episodios de crecidas catastróficas. En el período de estudio se registraron dos eventos de esta naturaleza. En este trabajo se describen también tanto las consecuencias derivadas de los mismos, como el papel tan destacado que jugó en su desarrollo un afluente del Ebro, el río Ciurana. Finalmente, los resultados obtenidos referentes a la dinámica fluvial, anterior y posterior a la construcción de los embalses, se aplican a la evolución sedimentaria del Delta del Ebro, formado a poca distancia del tramo estudiado
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