1,962 research outputs found

    Espacios rupestres como «obras abiertas»: una mirada a los procesos de confección y transformación de los abrigos con arte rupestre del este de Catamarca (Argentina)

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    In this paper we attempt to advance the understanding of the process of painting in caves with rock art at Ancasti’s Highlands (Catamarca Province, Argentina) from chemical analysis of pigment mixtures with which the paintings have been made. Thus, we suggest the possibility of understanding some of the art in these caves as «open works», i.e.: as the result of addition of motives over a process whose duration, perhaps long, we do not know.En este trabajo intentamos avanzar en el conocimiento del proceso de pintado de las cuevas con arte rupestre de la Sierra de Ancasti (Provincia de Catamarca, Argentina) a partir del análisis químico de las mezclas pigmentarias con las que fueron realizadas las pinturas. De este modo, planteamos la posibilidad de comprender algunos de estos abrigos pintados como «obras abiertas», es decir, como el resultado del agregado de motivos a lo largo de un proceso cuya duración, quizás larga, aún no conocemos

    Asteroseismology of the Hyades with K2: first detection of main-sequence solar-like oscillations in an open cluster

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    The Hyades open cluster was targeted during Campaign 4 (C4) of the NASA K2 mission, and short-cadence data were collected on a number of cool main-sequence stars. Here, we report results on two F-type stars that show detectable oscillations of a quality that allows asteroseismic analyses to be performed. These are the first ever detections of solar-like oscillations in main-sequence stars in an open cluster.Comment: 12 pages, 8 figures, 2 tables; accepted for publication in MNRA

    Resource-Bound Quantification for Graph Transformation

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    Graph transformation has been used to model concurrent systems in software engineering, as well as in biochemistry and life sciences. The application of a transformation rule can be characterised algebraically as construction of a double-pushout (DPO) diagram in the category of graphs. We show how intuitionistic linear logic can be extended with resource-bound quantification, allowing for an implicit handling of the DPO conditions, and how resource logic can be used to reason about graph transformation systems

    Eco-agri-food systems: today's realities and tomorrow's challenges

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    Provides an overview of the diversity of agriculture and food systems, each with different contributions to global food security, impacts on the natural resource base and ways of working through food system supply chains. We describe “eco-agri-food systems” and further identify their many manifestations through a review of typologies. We identify challenges ahead with existing systems due to prevailing economic and political pressures resulting in patterns of invisible flows and impacts across global food systems. We describe pathways to ensure sustainability by securing the benefits from working with, rather than against, natural systems and ecosystem processes and the challenges for farmers, communities and societies to reorient food value chains and build resilience in eco-agri-food systemsFil: Pengue, Walter Alberto. Universidad Nacional de General Sarmiento; Argentina. Universidad de Buenos Aires; ArgentinaFil: Gemmill Herren, Barbara. World Agroforestry Centre; KeniaFil: Balázs, Bálint. Environmental Social Science Research Group; HungríaFil: Ortega, Enrique. Universidade Estadual de Campinas; BrasilFil: Acevedo, Francisca. National Commission for the Knowledge and Use of Biodiversity,; MéxicoFil: Diaz, Daniel N,. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Díaz de Astarloa, Diego. Universidad Nacional de General Sarmiento; ArgentinaFil: Fernandez, Rosa. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Garibaldi, Lucas Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones En Recursos Naturales, Agroecología y Desarrollo Rural. - Universidad Nacional de Rio Negro. Instituto de Investigaciones En Recursos Naturales, Agroecología y Desarrollo Rural; ArgentinaFil: Giampietro, Mario. Universidad de Barcelona; EspañaFil: Goldberg, Andrea. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Khosla, Ashok. Development Alternatives; IndiaFil: Westhoek, Henk. PBL Netherlands Environmental Assessment Agency. Water, Agriculture and Food; Países Bajo

    CANDELS/GOODS-S, CDFS, ECDFS: Photometric Redshifts For Normal and for X-Ray-Detected Galaxies

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    We present photometric redshifts and associated probability distributions for all detected sources in the Extended Chandra Deep Field South (ECDFS). The work makes use of the most up-to-date data from the Cosmic Assembly Near-IR Deep Legacy Survey (CANDELS) and the Taiwan ECDFS Near-Infrared Survey (TENIS) in addition to other data. We also revisit multi-wavelength counterparts for published X-ray sources from the 4Ms-CDFS and 250ks-ECDFS surveys, finding reliable counterparts for 1207 out of 1259 sources (96%\sim 96\%). Data used for photometric redshifts include intermediate-band photometry deblended using the TFIT method, which is used for the first time in this work. Photometric redshifts for X-ray source counterparts are based on a new library of AGN/galaxy hybrid templates appropriate for the faint X-ray population in the CDFS. Photometric redshift accuracy for normal galaxies is 0.010 and for X-ray sources is 0.014, and outlier fractions are 4%4\% and 5.4%5.4\% respectively. The results within the CANDELS coverage area are even better as demonstrated both by spectroscopic comparison and by galaxy-pair statistics. Intermediate-band photometry, even if shallow, is valuable when combined with deep broad-band photometry. For best accuracy, templates must include emission lines.Comment: The paper has been accepted by ApJ. The materials we provide are available under [Surveys] > [CDFS] through the portal http://www.mpe.mpg.de/XraySurvey

    The short term debt vs. long term debt puzzle: a model for the optimal mix

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    This paper argues that the existing finance literature is inadequate with respect to its coverage of capital structure of small and medium sized enterprises (SMEs). In particular it is argued that the cost of equity (being both conceptually ill defined and empirically non quantifiable) is not applicable to the capital structure decisions for a large proportion of SMEs and the optimal capital structure depends only on the mix of short and long term debt. The paper then presents a model, developed by practitioners for optimising the debt mix and demonstrates its practical application using an Italian firm's debt structure as a case study

    CANDELS Multi-wavelength Catalogs: Source Detection and Photometry in the GOODS-South Field

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    We present a UV-to-mid infrared multi-wavelength catalog in the CANDELS/GOODS-S field, combining the newly obtained CANDELS HST/WFC3 F105W, F125W, and F160W data with existing public data. The catalog is based on source detection in the WFC3 F160W band. The F160W mosaic includes the data from CANDELS deep and wide observations as well as previous ERS and HUDF09 programs. The mosaic reaches a 5σ\sigma limiting depth (within an aperture of radius 0.17 arcsec) of 27.4, 28.2, and 29.7 AB for CANDELS wide, deep, and HUDF regions, respectively. The catalog contains 34930 sources with the representative 50% completeness reaching 25.9, 26.6, and 28.1 AB in the F160W band for the three regions. In addition to WFC3 bands, the catalog also includes data from UV (U-band from both CTIO/MOSAIC and VLT/VIMOS), optical (HST/ACS F435W, F606W, F775W, F814W, and F850LP), and infrared (HST/WFC3 F098M, VLT/ISAAC Ks, VLT/HAWK-I Ks, and Spitzer/IRAC 3.6, 4.5, 5.8, 8.0 μ\mum) observations. The catalog is validated via stellar colors, comparison with other published catalogs, zeropoint offsets determined from the best-fit templates of the spectral energy distribution of spectroscopically observed objects, and the accuracy of photometric redshifts. The catalog is able to detect unreddened star-forming (passive) galaxies with stellar mass of 10^{10}M_\odot at a 50% completeness level to z\sim3.4 (2.8), 4.6 (3.2), and 7.0 (4.2) in the three regions. As an example of application, the catalog is used to select both star-forming and passive galaxies at z\sim2--4 via the Balmer break. It is also used to study the color--magnitude diagram of galaxies at 0<z<4.Comment: The full resolution article is now published in ApJS (2013, 207, 24). 22 pages, 21 figures, and 5 tables. The catalogue is available on the CANDELS website: http://candels.ucolick.org/data_access/GOODS-S.html MAST: http://archive.stsci.edu/prepds/candels and Rainbow Database: https://arcoiris.ucolick.org/Rainbow_navigator_public and https://rainbowx.fis.ucm.es/Rainbow_navigator_publi

    Huntingtin-mediated axonal transport requires arginine methylation by PRMT6

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    The huntingtin (HTT) protein transports various organelles, including vesicles containing neurotrophic factors, from embryonic development throughout life. To better understand how HTT mediates axonal transport and why this function is disrupted in Huntington's disease (HD), we study vesicle-associated HTT and find that it is dimethylated at a highly conserved arginine residue (R118) by the protein arginine methyltransferase 6 (PRMT6). Without R118 methylation, HTT associates less with vesicles, anterograde trafficking is diminished, and neuronal death ensues—very similar to what occurs in HD. Inhibiting PRMT6 in HD cells and neurons exacerbates mutant HTT (mHTT) toxicity and impairs axonal trafficking, whereas overexpressing PRMT6 restores axonal transport and neuronal viability, except in the presence of a methylation-defective variant of mHTT. In HD flies, overexpressing PRMT6 rescues axonal defects and eclosion. Arginine methylation thus regulates HTT-mediated vesicular transport along the axon, and increasing HTT methylation could be of therapeutic interest for HD.Telethon-Italy and Autonomous Province of Trento (TCP12013 to M.P.); Association Française contre les Myopathies (AFM-22221 to M.P. and M.B.); PRIN-MUR (2017F2A2C5 to M.P.); National Institutes of Health (1R21NS111768-01 to M.P. and U.B.P.); PROGRAM RARE DISEASES CNCCS-Scarl-Pomezia (M.P.); FONDAZIONE AIRC-Italy (24423 to M.P.); Alzheimer Trento Onlus with the legato Baldrachi (M.B.); the Agence Nationale de la Recherche (ANR-15-JPWG-0003-05 JPND CIRCPROT and ANR-18-CE16-0009-01 AXYON to F.S.) and the Spanish Ministry of Science, Innovation and Universities (RTI2018-096322-B-I00 MCIU/AEI/FEDER-UE to J.J.L.
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