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Earthquake Engineering and Engineering Vibration 2013年第4期12卷 643-658页

作者： Matthieu Perrault philippe Gueguen Alexandru Aldea Sorin Demetriu Institut des Sciences de la Terre Université Joseph Fourier Grenoble ICNRS/IFSTTAR Technical University of Civil Engineering

The lack of knowledge concerning modelling existing buildings leads to significant variability in fragility curves for single or grouped existing buildings. This study aims to investigate the uncertainties of fragility curves, with special consideration of the single-building sigma. Experimental data and simplified models are applied to the BRD tower in Bucharest, Romania, a RC building with permanent instrumentation. A three-step methodology is applied：（1） adjustment of a linear MDOF model for experimental modal analysis using a Timoshenko beam model and based on Anderson＇s criteria, （2） computation of the structure＇s response to a large set of accelerograms simulated by SIMQKE software, considering twelve ground motion parameters as intensity measurements （IM）, and （3） construction of the fragility curves by comparing numerical interstory drift with the threshold criteria provided by the Hazus methodology for the slight damage state. By introducing experimental data into the model, uncertainty is reduced to 0.02 considering Sd ） as seismic intensity IM and uncertainty related to the model is assessed at 0.03. These values must be compared with the total uncertainty value of around 0.7 provided by the Hazus methodology.

关键词： vulnerability fragility curves uncertainty slight damage Timoshenko model Bucharest

CURDIS:A template for incremental curve discretization algorithms and its application to conics

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虚拟现实与智能硬件（中英文） 2024年第5期6卷 358-382页

作者： philippe LATOUR Marc VAN DROOGENBROECK Montefiore Institute University of LiègeQuartier Polytech 1Allée de la découverte 104000 LiègeBelgium

We introduce CURDIS,a template for algorithms to discretize arcs of regular curves by incrementally producing a list of support pixels covering the *** this template,algorithms proceed by finding the tangent quadrant at each point of the arc and determining which side the curve exits the pixel according to a tailored *** two elements can be adapted for any type of curve,leading to algorithms dedicated to the shape of specific *** the calculation of the tangent quadrant for various curves,such as lines,conics,or cubics,is simple,it is more complex to analyze how pixels are traversed by the *** the case of conic arcs,we found a criterion for determining the pixel exit *** leads us to present a new algorithm,called CURDIS-C,specific to the discretization of conics,for which we provide all the ***,the criterion for conics requires between one and three sign tests and four additions per pixel,making the algorithm efficient for resource-constrained systems and feasible for fixed-point or integer arithmetic *** algorithm also perfectly handles the pathological cases in which the conic intersects a pixel twice or changes quadrants multiple times within this pixel,achieving this generality at the cost of potentially computing up to two square roots per *** illustrate the use of CURDIS for the discretization of different curves,such as ellipses,hyperbolas,and parabolas,even when they degenerate into lines or corners.

关键词： Computer graphics Curve discretization Conics Rasterization Ellipse drawing Conic spline Conic pencil

Redox and acetylation coordinate ABA-independent osmotic stress response

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Molecular Plant 2022年第4期15卷 583-585页

作者： Christophe Belin Jean-philippe Reichheld Laboratoire Génome et Développement des Plantes UniversitéPerpignan Via Domitia66860 PerpignanFrance Laboratoire Génome et Développement des Plantes CNRS66860 PerpignanFrance

Osmotic stress caused by drought or high salt concentrations is a major threat that limits plant development and affect crop *** the context of climate change,understanding the mechanisms by which plants perceive their environment to adapt to their development is a major question.A common feature of plants being exposed to osmotic stress is the accumulation of excessive reactive oxygen species(ROS)(Martinière et al.,2019).ROS can oxidatively damage biological molecules,such as nucleic acids,proteins,and lipids,but also play important signaling *** protect from ROS-induced oxidation,living organisms have developed a large panel of enzymatic and non-enzymatic systems to remove ROS and oxidized molecules.

关键词： functions. enzymatic coordinate

Multiscale Hybrid-Mixed Finite Element Method for Flow Simulation in Fractured Porous Media

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Computer Modeling in Engineering & Sciences 2019年第4期119卷 145-163页

作者： philippe Devloo Wenchao Teng Chen-Song Zhang FEC Universidade Estadual de CampinasBrazil Tracy Energy Technologies BeijingChina NCMIS&LSEC Academy of Mathematics and System SciencesCASBeijingChina

The multiscale hybrid-mixed(MHM)method is applied to the numerical approximation of two-dimensional matrix fluid flow in porous media with *** two-dimensional fluid flow in the reservoir and the one-dimensional flow in the discrete fractures are approximated using mixed finite *** coupling of the two-dimensional matrix flow with the one-dimensional fracture flow is enforced using the pressure of the one-dimensional flow as a Lagrange multiplier to express the conservation of fluid transfer between the fracture flow and the divergence of the one-dimensional fracture flux.A zero-dimensional pressure(point element)is used to express conservation of mass where fractures *** issuing simulation is then reduced using the MHM method leading to accurate results with a very reduced number of global equations.A general system was developed where fracture geometries and conductivities are specified in an input file and meshes are generated using the public domain mesh generator *** test cases illustrate the effectiveness of the proposed approach by comparing the multiscale results with direct simulations.

关键词： Fracture simulation discrete fracture model multiscale hybrid finite element mixed formulation

Economic and Human Loss Empirical Models for Earthquakes in the Mediterranean Region, with Particular Focus on Algeria

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International Journal of Disaster Risk Science 2017年第4期8卷 415-434页

作者： Abdelheq Guettiche philippe Guguen Mostefa Mimoune Centre Universitaire Abdelhafid Boussouf Civil Engineering Department Universitdes Frères Mentouri Institut des Sciences de la Terre (ISTerre) Universitde Grenoble Alpes/CNRSIFSTTAR

In this study, loss estimation models were developed for reasonably accurate assessment of economic and human losses from seismic events in the Mediterranean region, based on damage assessment at an urban *** were compiled from existing worldwide databases,and completed with earthquake information from regional studies. Economic data were converted to a single common currency unit(2015 USD value) and the wealth of the areas affected by 65 earthquakes of the region from 1900 to 2015 was assessed. Reduced-form models were used to determine economic and human losses, with earthquake magnitude and intensity as hazard-related variables, and gross domestic product of the affected area and the affected population as exposure-related variables. Damage to buildings was also used as a hazard-related variable to predict economic and human losses. Finally, site-specific regression models were proposed for economic and human losses due to earthquakes in the Mediterranean region, and more specifically, in Algeria. We show that by introducing the damage variable into the models, prediction error can be reduced, and that accuracy of loss model estimation is site dependent and requires regional data on earthquake losses to improve. A case study for Constantine, Algeria shows the improvements needed for increased accuracy.

关键词： Algeria Earthquake loss estimation Mediterranean region Reduced-form models Seismic intensity Seismic magnitude

Proapoptotic RECS1: a requisite gateway to lysosomal dysfunction and death

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Neural Regeneration Research 2022年第12期17卷 2695-2696页

作者： philippe Pihán Mateus Milani Claudio Hetz Biomedical Neuroscience Institute Faculty of MedicineUniversity of ChileSantiagoChile Center for Geroscience Brain Health and Metabolism(GERO)SantiagoChile Program of Cellular and Molecular Biology Institute of Biomedical SciencesUniversity of ChileSantiagoChile Buck Institute for Research on Aging NovatoCAUSA

For a long time since their discovery by Christian de Duve in the 1950s,lysosomes have been referred to almost exclusively as passive garbage bags;the endpoint in the degradation of intra-and extracellular *** catabolic function of lysosomes is accomplished by an array of more than 60 acid hydrolases,which together break down a wide variety of biological macromolecules,including proteins,lipids,carbohydrates,and nucleic acids,for reutilization in the metabolic processes of the *** their optimal function,these enzymes require an acidic intraluminal pH of~4.5,which is maintained by the joint action of a proton pump,the vacuolar H+-ATPase,and several ion channels embedded in the lysosomal limiting membrane.

关键词： maintained limiting function

Success of three soil restoration techniques on seedling survival and growth of three plant species in the Sahel of Burkina Faso(West Africa)

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Journal of Forestry Research 2016年第2期27卷 313-320页

作者： philippe Bayen Anne Mette Lykke Adjima Thiombiano Laboratory of Plant Biology and Ecology University of Ouagadougou Department of Bioscience Aarhus University

In the Sahel of Africa, where 90 % of the population depends on natural resources for their liveli- hood, a large part of the soils are structurally unstable, prone to crusting and hard setting, and have low water holding capacity, which hamper vegetation establishment. The effect of soil restoration techniques on survival and growth of seedlings of Acacia nilotica, Acacia tortilis and Jatropha curcas was tested in completely barren, degraded land in a Sahelian ecosystem in Burkina Faso. A total of 522 seedlings （174 plants of each plant species） were planted in a randomized complete block design with three replicates combining three soil preparation techniques： half-moon, zai＂ and standard plantation. Survival and growth rates evaluated over 20 months were significantly higher using the half-moon technique compared with the other two techniques. Survival rates of plant species planted using half-moon technique were 62.5, 28.57 and 10.71% for A. nilotica, A. tortilis and J. curcas respec- tively, but in za＇i and standard planting, seedling survival was zero. The low survival rate of J. curcas using the half-moon technique may indicate that J. curcas is unsuit- able for barren and degraded land, whereas A. nilotica and A. tortilis appear to be promising tree species for rehabil- itation of degraded land.

关键词： Afforestation Bare soil Soil rehabilitation Species selection Water conservation

Effects of Polypropylene Fibers on the Physical and Mechanical Properties of Recycled Aggregate Concrete

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Journal of Wuhan University of Technology(Materials Science) 2019年第6期34卷 1327-1344页

作者： Pierre Matar Gérard-philippe Zéhil Lebanese University Faculty of EngineeringBranch 2RoumiehLebanon Notre Dame University-Louaize Faculty of EngineeringZouk MosbehLebanon

The viability of using polypropylene fibers(PPF) in concrete was largely studied. Yet, few of the existing research studies investigated the effects of PPF on the properties of concrete containing recycled concrete aggregate(RCA). Mixes with different RCA replacement ratios and different PPF content were designed and tested. The test results showed that the addition of PPF did not change significantly the compressive strength and the density of the concrete, but slightly decreased its modulus of elasticity and Poisson’s ratio. The drop in the splitting tensile strength and the flexural strength due to RCA inclusions was to a large extent compensated by the PPF addition. The water absorption decreased and the percent voids increased with increased PPF addition. Correlations between the RCA content, the PPF content and the properties of concrete were studied. Useful regression models were proposed to predict the properties of concrete in relevant ranges of RCA and PPF content.

关键词： concrete recycled aggregate fiber reinforcement physical properties mechanical properties

Beneficial effect of whole-grain wheat on liver fat:a role for the gut microbiota?

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Hepatobiliary Surgery and Nutrition 2021年第5期10卷 708-710页

作者： philippe Gérard Micalis Institute UniversitéParis-SaclayINRAEAgroParisTechJouy-en-JosasFrance

In meta-analyses of prospective studies,high whole grain(WG)intake has been acknowledged for its potential role in lowering risk of type 2 diabetes,cancer,cardiovascular disease and all cause mortality(1,2).Unlike Refined wheat(RW)flours from which the bran and germ of the wheat kernel have been removed,whole-grain wheat(WGW)products retain these elements and are rich sources not only of dietary fiber,but also of betaine,choline,important minerals and vitamins,components with antioxidant properties,and other phytochemicals(3).They are thus considered nutritionally superior but previous WG interventions in human subjects have reported conflicting results in improvements in health parameters.

关键词： grain wheat removed

Egg clutch patterning in Lestes virens （Odonata, Lestidae） with evolutionary emphasis on endophytic oviposition in lestid dragonflies

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Insect Science 2016年第6期23卷 893-902页

作者： Natalia A. Matushkina Denis Buy philippe Lambret Department of Zoology Institute of Biology Taras Shevchenko National University of Kyiv Kyiv 01033 Ukraine Institute of Food Biotechnology and Genomics NAS of Ukraine Kyiv 04123 Ukraine Tour du Valat Research Centre Le Sambuc Aries 13200 France

Egg deposition within plants is one of the most widely distributed and ancient behaviors in Odonata. The resulting clutch consists of eggs placed in peculiar pattern that can be a characteristic for certain groups of Odonata. Despite their importance for paleontological and evolutionary research, data on egg-clutch positioning are missing or insufficient for most species. Here, patterning of egg clutches in Lestes virens was measured and described in detail for the first time. The female usually produces a linear row of single eggs directed at an angle rightward or leftward to the longitudinal axis of plant substrate. Less often eggs are arranged in egg-sets consisting of up to 4 eggs. Apparently, the female insect follows the rigid behavior stereotypes during oviposition and is unable to easily switch to the alternate stereotypical behavior of single egg deposition or production of multiegg sets. Based on a literature review and original data, egg clutch patterning of European Lestidae is overlaid on preexisting phylogenies. The resulting evolutionary scenario of egg-clutch patterning can be considered in the framework of egg-laying behavior in Lestidae.

关键词： behavior egg deposition endophytic oviposition evolution paleontology phylogeny