760 research outputs found

    7,9-Bis(hy­droxy­meth­yl)-7H-purine-2,6,8(1H,3H,9H)trione

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    The structure of the title uric acid derivative, C7H8N4O5, from human kidney stones, is characterized by the C and O atoms of one of the two hy­droxy­methyl groups being disordered nearly equally over three different sites. In the crystal, mol­ecules are connected by a three-dimensional hydrogen-bonding scheme though they look stacked in planes nearly parallel to (04)

    FishMark: A Linked Data Application Benchmark

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    Abstract. FishBase is an important species data collection produced by the FishBase Information and Research Group Inc (FIN), a not-forprofit NGO with the aim of collecting comprehensive information (from the taxonomic to the ecological) about all the world’s finned fish species. FishBase is exposed as a MySQL backed website (supporting a range of canned, although complex queries) and serves over 33 million hits per month. FishDelish is a transformation of FishBase into LinkedData weighing in at 1.38 billion triples. We have ported a substantial number of FishBase SQL queries to FishDelish SPARQL query which form the basis of a new linked data application benchmark (using our derivative of the Berlin SPARQL Benchmark harness). We use this benchmarking framework to compare the performance of the native MySQL application, the Virtuoso RDF triple store, and the Quest OBDA system on a fishbase.org like application.

    Combined Weekly Coordinate Solutions from SLR and DORIS

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    In International Terrestrial Reference Frame (ITRF) 2005 and ITRF2008, the approach for the construction of solutions by the IERS has been for individual analysis centers of each technique to process geodetic tracking data, and for each technique to develop a solution (or contribution) that is integrated into the final ITRF solution by careful combination of the technique solutions. The connections between the geodetic networks are realized by the application of local ties. In an alternate approach, we may assure processing homogeneity by creating normal equations for different techniques with the same orbit determination software, using identically derived algorithms. Another derivative of this approach is to realize the ties between the techniques using satellites tracked with multiple techniques; in effect tieing the networks together using satellite dynamics. In this solution, we develop a time series and a set of cumulative solutions from Satellite Laser Ranging (SLR) & Doppler Orbitography and Radio-positioning Integrated by Satellite (DORIS) based on homogeneous processing with the NASA GEODYN precise orbit determination suite of programs, where we jointly combine weekly the SLR data to Lageos1, Lageos2, Starlette, and Stella with the DORIS data from SPOT2-SPOT5, as well as satellites that utilize both techniques (TOPEX/Poseidon, Envisat, Jason-2). We discuss the modeling that is applied including upgrades implemented since the submission of the GSC ITRF2008 contributions for IDS. Firstly, we compare the SLR-only solutions comprising four geodetic satellites with the standard approach of utilizing only Lageos1 & Lageos2. Secondly, we evaluate the impact on the DORIS coordinates of the joint analysis with the SLR data

    The attitudes of European consumers toward innovation in bread; interest of the consumers toward selected quality attributes

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    16 pages, 7 tables, 4 figures.-- The definitive version is available at www3.interscience.wiley.comThe present survey is integrated in the European project entitled EU-FRESHBAKE. This three years project started in October 2006. It aims at developing innovative processes and innovative formulations for the Bake Off technology taking into consideration, energy demand of the process, nutrition parameters and overall quality of the bread. To help and to advise the project on the expectations of the European consumers toward innovation, a consumer survey has been carried out taking into consideration 1050 consumers from 5 countries (Belgium, Croatia, Spain, France and Poland). The global objectives are (i) to better understand the attitudes of the European innovations in bread and (ii) to understand the main determinants of it. Globally the key points that arose from the survey were the environmental concern and the concern regarding health; these two aspects seem to steer the attitudes of the consumer. Basically, two categories of consumers were observed; (i) frequent (daily) buyers with a focus on quality and pleasure and (ii) less frequent buyers (once a week) with a more pronounced interest in nutrition and energy (process). The first group was named the crust group and the second one the crumb group. The crumb family seems to be the one that is the most interested in the outcomes of the EU-FRESHBAKE project. This group is concerned by nutrition quality and would prefer a bread which has been done with a less energy demanding process. The “crust” group is schematically less interested in the nutrition, in the shelf life and in the energy demand of the process used to prepare the bread. The results from this survey should be handled with care due to the relative small size of the sample and to the fact that the average age of the sample was rather young.This study (report, paper, workshop…) has been carried out with financial support from the Commission of the European Communities, FP6, Thematic Area “Food quality and safety”, FOOD-2006-36302 EU-FRESH BAKE.Peer reviewe

    Burst Testing of Triaxial Braided Composite Tubes

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    Applications using triaxial braided composites are limited by the materials transverse strength which is determined by the delamination capacity of unconstrained, free-edge tows. However, structural applications such as cylindrical tubes can be designed to minimize free edge effects and thus the strength with and without edge stresses is relevant to the design process. The transverse strength of triaxial braided composites without edge effects was determined by internally pressurizing tubes. In the absence of edge effects, the axial and transverse strength were comparable. In addition, notched specimens, which minimize the effect of unconstrained tow ends, were tested in a variety of geometries. Although the commonly tested notch geometries exhibited similar axial and transverse net section failure strength, significant dependence on notch configuration was observed. In the absence of unconstrained tows, failure ensues as a result of bias tow rotation, splitting, and fracture at cross-over regions

    Determination of the high-pressure crystal structure of BaWO4 and PbWO4

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    We report the results of both angle-dispersive x-ray diffraction and x-ray absorption near-edge structure studies in BaWO4 and PbWO4 at pressures of up to 56 GPa and 24 GPa, respectively. BaWO4 is found to undergo a pressure-driven phase transition at 7.1 GPa from the tetragonal scheelite structure (which is stable under normal conditions) to the monoclinic fergusonite structure whereas the same transition takes place in PbWO4 at 9 GPa. We observe a second transition to another monoclinic structure which we identify as that of the isostructural phases BaWO4-II and PbWO4-III (space group P21/n). We have also performed ab initio total energy calculations which support the stability of this structure at high pressures in both compounds. The theoretical calculations further find that upon increase of pressure the scheelite phases become locally unstable and transform displacively into the fergusonite structure. The fergusonite structure is however metastable and can only occur if the transition to the P21/n phases were kinetically inhibited. Our experiments in BaWO4 indicate that it becomes amorphous beyond 47 GPa.Comment: 46 pages, 11 figures, 3 table

    Physcomitrium patens PpRIC, an ancestral CRIB-domain ROP effector, inhibits auxin-induced differentiation of apical initial cells

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    RHO guanosine triphosphatases are important eukaryotic regulators of cell differentiation and behavior. Plant ROP (RHO of plant) family members activate specific, incompletely characterized downstream signaling. The structurally simple land plant Physcomitrium patens is missing homologs of key animal and flowering plant RHO effectors but contains a single CRIB (CDC42/RAC interactive binding)-domain -contain-ing RIC (ROP-interacting CRIB-containing) protein (PpRIC). Protonemal P. patens filaments elongate based on regular division and PpROP-dependent tip growth of apical initial cells, which upon stimulation by the hor-mone auxin differentiate caulonemal characteristics. PpRIC interacts with active PpROP1, co-localizes with this protein at the plasma membrane at the tip of apical initial cells, and accumulates in the nucleus. Remark-ably, PpRIC is not required for tip growth but is targeted to the nucleus to block caulonema differentiation downstream of auxin-controlled gene expression. These observations establish functions of PpRIC in medi-ating crosstalk between ROP and auxin signaling, which contributes to the maintenance of apical initial cell identity

    Approaches for Tensile Testing of Braided Composites

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    For angleply composites, lamina tension and compression strengths are commonly determined by applying classical lamination theory to test data obtained from testing of angleply composite specimens. For textile composites such as 2D triaxial braids, analysis is more complex and standard test methods do not always yield reliable strength measurements. This paper describes recent research focused on development of more reliable tensile test methods for braided composites and presents preliminary data for various approaches. The materials investigated in this work have 0deg+/-60 2D triaxial braid architecture with nearly equal fiber volume fraction in each of the three fiber directions. Flat composite panels are fabricated by resin transfer molding (RTM) using six layers of the braided preform aligned along the 0deg fiber direction. Various epoxy resins are used as matrix materials. Single layer panels are also fabricated in order to examine local variations in deformation related to the braid architecture. Specimens are cut from these panels in the shape of standard straight-sided coupons, an alternative bowtie geometry, and an alternative notched geometry. Axial tensile properties are measured using specimens loaded along the 0deg fiber direction. Transverse tensile properties are measured using specimens loaded perpendicular to the 0deg fibers. Composite tubes are also fabricated by RTM. These tubes are tested by internal pressurization using a soft rubbery material sealed between the inside diameter of the tube and the load fixtures. The ends of the tube are unconstrained, so the primary load is in the hoop direction. Tubes are fabricated with the 0deg fibers aligned along the tube axis by overbraiding the preform on a mandrel. Since the loading is in the hoop direction, testing of the overbraided tube provides a measure of transverse tensile strength. Previous work has indicated that straight-sided coupons yield a transverse tensile strength that is much lower than the expected material strength because of premature edge-initiated failure. Full-field strain measured during transverse tensile tests clearly showed accumulation of edge damage prior to failure. In the current work, high speed video and testing of single layer specimens are used to investigate potential failure mechanisms in more detail. High speed video clearly shows the edge initiation in six layer transverse tensile test coupons. Specimens with the bowtie geometry and the notched geometry minimize this edge effect and yield significantly higher transverse tensile strength values compared to the straight-sided coupons. However, bowtie and notched specimens geometries are not ideal because of the non-uniform stress and strain fields in the region of failure. Testing of tubes using internal pressurization eliminates edge-initiated failure and provides a more uniform state of stress and strain. Preliminary results indicate that bowtie, notched, and tube specimens yield comparable values for transverse tensile strength and that these values are much higher than the strength measured using a straight-sided coupon

    Resposta de cultivares de batata a nĂ­veis crescentes de NPK.

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    Made available in DSpace on 2018-02-05T23:36:03Z (GMT). No. of bitstreams: 1 ArionePereiraRespostadecultivaresdebatata.pdf: 359213 bytes, checksum: beab41c27497ae35cd61908f3db72e4c (MD5) Previous issue date: 2018-02-05bitstream/item/172171/1/Arione-Pereira-Resposta-de-cultivares-de-batata.pd
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