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  • Open Access
    Authors: 
    Massimo Nespolo; Bernd Souvignier;
    Countries: Netherlands, France

    International audience; Author(s) of this paper may load this reprint on their own web site or institutional repository provided that this cover page is retained. Republication of this article or its storage in electronic databases other than as specified above is not permitted without prior permission in writing from the IUCr. For further information see http://journals.iucr.org/services/authorrights.html Many research topics in condensed matter research, materials science and the life sciences make use of crystallographic methods to study crystalline and non-crystalline matter with neutrons, X-rays and electrons. Articles published in the Journal of Applied Crystallography focus on these methods and their use in identifying structural and diffusion-controlled phase transformations, structure–property relationships, structural changes of defects, interfaces and surfaces, etc. Developments of instrumentation and crystallographic apparatus, theory and interpretation, numerical analysis and other related subjects are also covered. The journal is the primary place where crystallographic computer program information is published.

  • Open Access English
    Authors: 
    Hicham Jabraoui; Etienne Paul Hessou; Siwar Chibani; Laurent Cantrel; Sébastien Lebègue; Michael Badawi;
    Publisher: HAL CCSD
    Country: France

    International audience; The ability of Ag-exchanged mordenite (Ag-MOR)to capture iodine species such as I2 and CH3I as released for instance during a nuclear accident could be severely limited by the presence of volatile organic compounds (VOCs)that can disrupt their adsorption in the zeolite. Here, using density functional theory (DFT), we investigate in detail the adsorption process of several hydrocarbons (methane, cyclohexane, benzene, and 1,3-dimethylbenzene)and oxygenated compounds (methanol, ethanol, propan-2-ol and propanone)and compare it with the adsorption of I2 and CH3I for different values of the Si/Al ratio of the Ag-exchanged mordenite. It is found that the adsorption process of the iodine species becomes favorable as the Si/Al ratio is decreased. Indeed at high Si/Al ratio, some VOCs such as benzene, 1, 3-dimethylbenzene and propan-2-ol exhibit strong inhibiting effects, while at low Si/Al ratio, only the adsorption of CH3I is limited by the presence of aromatic hydrocarbons. Also, in addition to the elongation of the I[sbnd]I bond upon the adsorption of the iodine molecule in Ag-MOR with a high silver content, we found that there is a significant electron transfer between the Ag and I atoms. Thus, our results indicate that the I[sbnd]I bond becomes weaker during the adsorption and therefore the formation of AgI precipitates is favored. © 2019 Elsevier B.V.

  • Open Access
    Authors: 
    G. Muñoz; Cristina Óvilo; Jordi Estellé; Luis Silió; Almudena Fernández; Carmen Rodríguez;
    Publisher: Springer Science and Business Media LLC
    Countries: France, Spain

    Abstract The objective of this study was to search for polymorphisms in the coding region of the estrogen receptors 1 and 2 (ESR1 and ESR2 )and to analyze the effects of these variants and the well known intronic ESR1 Pvu II polymorphism on litter size in a Chinese-European pig line. We identified five silent single nucleotide polymorphisms (SNP) in the ESR1 cDNA: c.669T > C (exon 3), c.1227C > T (exon 5), c.1452C > T (exon 7), c.1665T > C and c.1755A > G (exon 8). One pair of these SNP (c.1665T > C and c.1755A > G) co-segregated in the analyzed line, and the SNP c.669T > C showed the same segregation pattern as the Pvu II polymorphism. These polymorphisms were tested in this study, although the c.1452C > T SNP within exon 7 was not analyzed due to its low informativeness. In the ESR2 cDNA, one missense SNP was found within exon 5, which caused an amino acid substitution in the coded protein: "c.949G > A (p.Val317Met)" and was tested on sow litter size. Information on 1622 litter records from 408 genotyped sows was analyzed to determine whether these SNP influenced the total number of piglets born (TNB) or the number of born alive (NBA). The polymorphisms ESR1: [Pvu II; c.669T > C], ESR1: [c.1665T > C; c.1755A > G] and ESR2: c.949G > A showed no statistically significant association with litter size. However, the ESR1: c.1227T allele was significantly associated with TNB. The additive substitution effect was estimated to be 0.40 piglets born per litter (P < 0.03), and no dominance effects were observed. This SNP could be useful in assisted selection for litter size in some pig lines, as a new genetic marker in linkage disequilibrium with the causative mutation.

  • Open Access English
    Authors: 
    Frédéric Jurie;
    Publisher: HAL CCSD
    Country: France

    International audience; We propose an efficient method for tracking 3D modelled objects in cluttered scenes. Rather than tracking objects in the image, our approach relies on the object recognition aspect of tracking. Candidate matches between image and model features define volumes in the space of transformations. The volumes of the pose space satisfying the maximum number of correspondences are those that best align the model with the image. Object motion defines a trajectory in the pose space. We give some results showing that the presented method allows tracking of objects even when they are totally occluded for a short while, without supposing any motion model and with a low computational cost (below 200 ms per frame on a basic workstation). Furthermore, this algorithm can also be used to initialize the tracking.

  • Publication . Conference object . Article . 2021
    Open Access English
    Authors: 
    A. Adil; Ibrahima N'Doye; Ali Zemouche; Abdelghani Hamaz; Taous-Meriem Laleg-Kirati;
    Publisher: HAL CCSD
    Country: France

    Published in IFAC-PapersOnLine, 54(14):96:101, 2021; International audience; The coupled tanks system is a widely used nonlinear system for testing control and estimation methods. This system has various applications such as wastewater treatment, water desalination, pharmaceutical industries, and petrochemical plants. Among the challenging problems is the water level estimation which is needed for controlling the system. In this paper, a high-gain like observer is proposed for the estimation of the water level from delayed output measurement. This observer tolerates a larger bound of the time-delay compared to that obtained by using standard high-gain approach. We show the effectiveness of such observer design and how the standard approach fails to reconstruct the water level in the tanks in the presence of a larger bound on the time-delay.

  • Open Access English
    Authors: 
    Vladik Kreinovich; Christelle Jacob; Didier Dubois; Janette Cardoso; Martine Ceberio; Ildar Z. Batyrshin;
    Publisher: HAL CCSD
    Country: France
    Project: NIH | Enhancement of Quantitati... (1T36GM078000-01), NIH | Enhancement of Quantitati... (1T36GM078000-01)

    In many real-life applications (e.g., in aircraft maintenance), we need to estimate the probability of failure of a complex system (such as an aircraft as a whole or one of its subsystems). Complex systems are usually built with redundancy allowing them to withstand the failure of a small number of components. In this paper, we assume that we know the structure of the system, and, as a result, for each possible set of failed components, we can tell whether this set will lead to a system failure. For each component A, we know the probability P(A) of its failure with some uncertainty: e.g., we know the lower and upper bounds P(A) and P(A) for this probability. Usually, it is assumed that failures of different components are independent events. Our objective is to use all this information to estimate the probability of failure of the entire the complex system. In this paper, we describe several methods for solving this problem, including a new efficient method for such estimation based on Cauchy deviates.

  • Open Access English
    Authors: 
    Gorisse, T.; Dupré, L.; Gentile, P.; Martin, M.; Zelsmann, M.; Buttard, D.;
    Publisher: HAL CCSD
    Country: France

    In this work, nanoimprint lithography combined with standard anodization etching is used to make perfectly organised triangular arrays of vertical cylindrical alumina nanopores onto standard −oriented silicon wafers. Both the pore diameter and the period of alumina porous array are well controlled and can be tuned: the periods vary from 80 to 460 nm, and the diameters vary from 15 nm to any required diameter. These porous thin layers are then successfully used as templates for the guided epitaxial growth of organised mono-crystalline silicon nanowire arrays in a chemical vapour deposition chamber. We report the densities of silicon nanowires up to 9 × 109 cm−2 organised in highly regular arrays with excellent diameter distribution. All process steps are demonstrated on surfaces up to 2 × 2 cm2. Specific emphasis was made to select techniques compatible with microelectronic fabrication standards, adaptable to large surface samples and with a reasonable cost. Achievements made in the quality of the porous alumina array, therefore on the silicon nanowire array, widen the number of potential applications for this technology, such as optical detectors or biological sensors.

  • Open Access English
    Authors: 
    Emmanuelle Bignon; Tomáš Dršata; Christophe Morell; Filip Lankaš; Elise Dumont;
    Publisher: HAL CCSD
    Country: France
    Project: ANR | PRIMES (ANR-11-LABX-0063), ANR | Avenir L.S.E. (ANR-11-IDEX-0007)

    International audience; Oxidatively-generated interstrand cross-links rank among the most deleterious DNA lesions. They originate from abasic sites, whose aldehyde group can form a covalent adduct after condensation with the exocyclic amino group of purines, sometimes with remarkably high yields. We use explicit solvent molecular dynamics simulations to unravel the structures and mechanical properties of two DNA sequences containing an interstrand cross-link. Our simulations palliate the absence of experimental structural and stiffness information for such DNA lesions and provide an unprecedented insight into the DNA embedding of lesions that represent a major challenge for DNA replication, transcription and gene regulation by preventing strand separation. Our results based on quantum chemical calculations also suggest that the embedding of the ICL within the duplex can tune the reaction profile, and hence can be responsible for the high difference in yields of formation.

  • Publication . Other literature type . Article . 2010
    Open Access English
    Authors: 
    Børge G. Nordestgaard; M. John Chapman; Kausik K. Ray; Jan Borén; Felicita Andreotti; Gerald F. Watts; Henry N. Ginsberg; Pierre Amarenco; Alberico L. Catapano; Olivier S. Descamps; +9 more
    Publisher: HAL CCSD
    Countries: Turkey, France, France, France, Netherlands, France, Croatia, Netherlands, France, France ...

    International audience; AIMS: The aims of the study were, first, to critically evaluate lipoprotein(a) [Lp(a)] as a cardiovascular risk factor and, second, to advise on screening for elevated plasma Lp(a), on desirable levels, and on therapeutic strategies. METHODS AND RESULTS: The robust and specific association between elevated Lp(a) levels and increased cardiovascular disease (CVD)/coronary heart disease (CHD) risk, together with recent genetic findings, indicates that elevated Lp(a), like elevated LDL-cholesterol, is causally related to premature CVD/CHD. The association is continuous without a threshold or dependence on LDL- or non-HDL-cholesterol levels. Mechanistically, elevated Lp(a) levels may either induce a prothrombotic/anti-fibrinolytic effect as apolipoprotein(a) resembles both plasminogen and plasmin but has no fibrinolytic activity, or may accelerate atherosclerosis because, like LDL, the Lp(a) particle is cholesterol-rich, or both. We advise that Lp(a) be measured once, using an isoform-insensitive assay, in subjects at intermediate or high CVD/CHD risk with premature CVD, familial hypercholesterolaemia, a family history of premature CVD and/or elevated Lp(a), recurrent CVD despite statin treatment, ≥3% 10-year risk of fatal CVD according to European guidelines, and/or ≥10% 10-year risk of fatal + non-fatal CHD according to US guidelines. As a secondary priority after LDL-cholesterol reduction, we recommend a desirable level for Lp(a) <80th percentile (less than ∼50 mg/dL). Treatment should primarily be niacin 1-3 g/day, as a meta-analysis of randomized, controlled intervention trials demonstrates reduced CVD by niacin treatment. In extreme cases, LDL-apheresis is efficacious in removing Lp(a). CONCLUSION: We recommend screening for elevated Lp(a) in those at intermediate or high CVD/CHD risk, a desirable level <50 mg/dL as a function of global cardiovascular risk, and use of niacin for Lp(a) and CVD/CHD risk reduction.

  • Publication . Preprint . Article . Conference object . 2018
    Open Access English
    Authors: 
    Moser, Daniel; Abele, Hartmut; Bosina, Joachim; Fillunger, Harald; Soldner, Torsten; Wang, Xiangzun; Zmeskal, Johann; Konrad, Gertrud;
    Publisher: HAL CCSD
    Country: France
    Project: FWF | Particles and Interaction... (W 1252)

    The beta decay of the free neutron provides several probes to test the Standard Model of particle physics as well as to search for extensions thereof. Hence, multiple experiments investigating the decay have already been performed, are under way or are being prepared. These measure the mean lifetime, angular correlation coefficients or various spectra of the charged decay products (proton and electron). NoMoS, the Neutron decay prOducts MOmentum Spectrometer, presents a novel method of momentum spectroscopy: it utilizes the $R \times B$ drift effect to disperse charged particles dependent on their momentum in an uniformly curved magnetic field. This spectrometer is designed to precisely measure momentum spectra and angular correlation coefficients in free neutron beta decay to test the Standard Model and to search for new physics beyond. With NoMoS, we aim to measure inter alia the electron-antineutrino correlation coefficient $a$ and the Fierz interference term $b$ with an ultimate precision of $\Delta a/a < 0.3\%$ and $\Delta b < 10^{-3}$ respectively. In this paper, we present the measurement principles, discuss measurement uncertainties and systematics, and give a status update. Comment: 7 pages, 4 figures, accepted to the Proceedings of the International Workshop on Particle Physics at Neutron Sources PPNS 2018, Grenoble, France, May 24-26, 2018

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