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International Journal of Sediment Research 2020年第3期35卷 295-306页

作者： Wei Zhang Miguel Uh Zapata Xin Bai Damien Pham-Van-Bang Kim Dan Nguyen laboratory for Hydraulics Saint-Venant (LHSV ENPC-EDF R&D-Cerema)University Paris-Est CONACYT Centro de Investigacion en Matematicas A.C.(CIMAT)Unidad Merida 3. Laboratory for Hydraulics and Environment (LHE)Institut National de La Recherche ScientifiqueUniversite Du Quebec

A large Eddy Simulation model is developed to simulate the hydrodynamics and scour process around a circular *** Navier-Stokes solver is based on the projection method and a second-order unstructured finite-volume method.A sigma-coordinate system is used to obtain an accurate representation of the evolution of the sediment-water *** erosion is simulated by solving the sediment continuity equation using a mass-conservating sand-slide algorithm and a bedload transport rate,which is based on a description of physical processes(Engelund & Freds(?)e,1976).Simulations of flow around a vertical cylinder for free-slip bed,rigid bed,and live-bed cases are *** mean velocity profile and shear stress validate the accuracy of this *** vortex and lee-wake vortex shedding structure are simulated,and the results are thoroughly discussed in *** formation and the temporal development of the scour hole and other topographic bed features are successfully *** current paper reports the first known investigation of both scour evolution and coherent structure using large-eddy simulation.

关键词： Non-hydrostatic flows Horseshoe vortex Wake region Scouring Bedload transport

Effects of Cadmium on Polar Lipid Composition and Unsaturation in Maize(Zea mays) in Hydroponic Culture

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Journal of Integrative Plant Biology 2007年第12期49卷 1693-1702页

作者： Radhouane Chaffai Tinni Nouhou Seybou Brahim Marzouk Ezzedine EI Ferjani laboratoire de Bio-Physiologie Cellulaires Vegetales Faculte des Sciences de Bizerte 7021 Zarzouna-BizerteTunisie laboratoire ERTAC Physiologie et Genetique Vegetales 63177 AubiereClermont FerrandFrance laboratoire d'Adaptation et d'Amelioration des Plantes Institut National de la Recherche Scientifique et Technique(INRST)BP 95-2050 Hammam-LifTunisie

This study aimed to evaluate the effect of Cd exposure （100 μmol/L） on polar lipid composition, and to examine the level of fatty acid unsaturation in maize （Zea mays L.）. In roots, the level of 16：0 and monounsaturated fatty acids （16：1 ＋ 18：1） decreased in phosphatidylcholine （PC） and phosphatidylethanolamine （PE）. In contrast, the proportion of unsaturated 18-C fatty acid species showed an opposite response to Cd. The content, on the other hand, of PC, PE, digalactosyldiacylglycerol （DGDG）, and steryl lipids increased in roots （2.9-, 1.6-, 5.3-, and 1.7-fold increase, respectively）. These results suggest that a more unsaturated fatty acid composition than found in control plants with a concomitant increase in polar lipids may favor seedling growth during Cd exposure. However, the observed increase in the steryl lipid （SL）： phospholipid （PL） ratio （twofold）, the decrease in monogalactosyldiacylglycerol （MGDG）： DGDG ratio, as well as the induction of lipid peroxidation in roots may represent symptoms of membrane injury. In shoots, the unsaturation level was markedly decreased in PC and phosphatidylglycerol （PG） after Cd exposure, but showed a significant increase in sulfoquinovosyldiacylglycerol （SQDG）, MGDG and DGDG. The content of PG and MGDG was decreased by about 65%, while PC accumulated to higher levels （4.4-fold increase）. Taken together, these changes in the polar lipid unsaturation and composition are likely to be due to alterations in the glycerolipid pathway. These results also support the idea that the increase in overall unsaturation plays some role in enabling the plant to withstand the metal exposure.

关键词： cadmium fatty acids heavy metal stress lipid peroxidation polar lipids unsaturation level Zea mays.

Revisiting the Plant＇s Dilemma

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Molecular Plant 2016年第1期9卷 7-9页

作者： Jeffrey Leung Nadia Bazihizina Stefano Mancuso Christiane Valon institut de Biologie Inté grative de la Cellule Universit&eacute de Paris Saclay-Centre d'Energie Atomique Centre National de la Recherche Scientifique UMR9198 1 Avenue de la Terrasse B&acirc timent 23 91198 Gif-sur-Yvette Cedex France LINV-DISPAA Universit&agrave degli Studi di Firenze Viale delle idee 30 50019 Sesto Fiorentino Italy

In the opening salvos of his engaging article, How Stomata Resolve the Dilemma of Opposing Priorities, Raschke （1976） wrote that “land plants are in a dilemma throughout their lives： assimilation of CO2 from the atmosphere requires intensive gas exchange; the prevention of excessive water loss demands that gas exchange be kept low.” What seemed a rarefied musing of a plant academic nearly 40 years ago has since broadened into alobal environmental concerns.

关键词： Plant physiology Photosynthesis Drought-tolerant plants

Engineering of electrocatalyst/electrolyte interface for ambient ammonia synthesis

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SusMat 2021年第2期1卷 150-173页

作者： Lei Du Lixin Xing Gaixia Zhang Xianhu Liu Diane Rawach Shuhui Sun institut national de la recherche scientifique(INRS)-CenterÉnergie Matériaux et Télécommunications VarennesQuébec J3X 1S2Canada School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001P.R.China Key laboratory of Materials Processing and Mold Ministry of EducationZhengzhou UniversityZhengzhou 450002P.R.China

Ammonia is not only an important platform chemical for industrial and agri-cultural use but is also a novel energy-carrying *** electrochemical reduction method for ambient ammonia synthesis is emerging as a promising strategy for the replacement of the current Haber–Bosch ammonia synthesis method,which consumes a large amount of energy and natural gas(hydrogen resource)while releasing substantial greenhouse gases(eg,carbon dioxide).The challenges in electrochemical ammonia synthesis,also known as nitrogen reduc-tion reaction,primarily include the cleavage of extremely stable N≡N bonds and the competitive hydrogen evolution reaction in routine aqueous media,which significantly leads to a low production rate and Faradaic *** ratio-nal design and engineering of the electrocatalyst/electrolyte interface are crucial to address these ***,recent achievements for catalyst/electrolyte interface engineering are reviewed to provide insights into enhancing the pro-duction rate and Faradaic *** on future research and devel-opment of the electrochemical ammonia synthesis from theory to practice will be provided.

关键词： ammonia synthesis Faradaic efficiency interfacial effects nitrogen reduction reaction pro-duction rate

Sperm limitation affects sex allocation in a parasitoid wasp Nasonia vitripennis

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Insect Science 2019年第5期26卷 853-862页

作者： Marlene Chirault Christophe Bressac Marlene Goubault Charlotte Lecureuil institut de recherche sur la Biologie de I'lnsecte UMR 7261 CNRS - Universite de ToursFaculte des Sciences et TechniquesParc GrandmontToursFrance

Insect reproduction is influenced by various external factors including temperature, a well-studied constraint. We investigated to what extent different levels of sperm limitation of males exposed to different heat stresses (34 and 36℃) afFect fem ales' offspring production and sex allocation in Nasonia vitripennis. In this haplodiploid parasitoid wasp attacking different species of pest flies, we investigated the effect of the quantity of sperm females received and stored in their spermatheca on their sperm use decisions, hence sex allocation, over successive ovipositions. In particular, we compared the sex allocation of females presenting three levels of sperm limitation (i.e.,mated with control, 34 ℃ heat-stressed or 36℃heat-stressed males) on each host they parasitized. To disentangle the potential reduction of sperm quality after a heat stress exposure from that of sperm quantity, we also explored the clutch size and sex ratio produced by fem ales that were partially sperm limited after copulating with multiply mated males. Independently of their sperm numbers, all types of fem ales produced a similar total number of offspring, but the more limited ones had fewer daughters. Sperm limitation further affected the distribution of daughters' production across *** addition to constraints acting on female physiology, male fertility should therefore be considered in studies measuring reproductive outputs of insects submitted to heat stresses.

关键词： heat stress multiple mating offspring production dynamic sex ratio sperm stock sperm use

Kinetic and product studies of the reactions of NO3 with a series of unsaturated organic compounds

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Journal of Environmental Sciences 2020年第9期32卷 111-120页

作者： Yangang Ren Max McGillen Ibrahim Ouchen Veronique Daële Abdelwahid Mellouki Centre national de la recherche scientifique(CNRS)(UPR 3021) Observatoire des Sciences de l’Univers en région Centre(OSUC)Institut de CombustionAérothermiqueRéactivitéet Environnement(ICARE)Orléans 45071France Earth Sciences department Scientific InstituteMohammed V UniversityRabat 10106Morocco Le Studium Loire Valley institute for Advanced Studies Orléans 45071France

Rate coefficients for the reaction of N03 radicals with 6 unsaturated volatile organic compounds(VOCs) in a 7300 L simulation chamber at ambient temperature and pressure have been determined by the relative rate *** resulting rate coefficients were determined for isoprene,2-carene,3-carene,methyl vinyl ketone(MVK),methacrolein(MACR)and crotonaldehyde(CA),as(6.6±0.8)×10-13,(1.8±0.6)×10-11,(8.7±0.5)×10-12,(1.24±1.04)×10-16,(3.3±0.9)×10-15 and(5.7±1.2)×10-15 cm3/(molecule·sec),*** experiments indicate that NO3 radical reactions with all the studied unsaturated VOGs proceed through addition to the olefinic bond,however,it indicates that the introduction of a carbonyl group into unsaturated VOGs can deactivate the neighboring olefinic bond towards reaction with the NO3 radical,which is to be expected since the presence of these electronwithdrawing substituents will reduce the electron density in the π orbitals of the alkenes,and will therefore reduce the rate coefficient of these electrophilic addition *** addition,we investigated the product formation from the reactions of 2-carene and 3-carene with the NO3 *** identification of an epoxide(C10H16OH+),caronaldehyde(C10H16O2 H+) and nitrooxy-ketone(C10H16O4 NH+) was achieved using a proton transfer reaction time-of-flight mass spectrometer(PTR-TOF-MS) and a reaction mechanism is proposed.

关键词： Rate coefficient NO_(3) radical Products Volatile organic compounds(VOCs)

Non-Linear Phase Tomography Based on Fréchet derivative

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Advances in Computed Tomography 2014年第4期3卷 39-50页

作者： Valentina Davidoiu Bruno Sixou Max langer Franoise Peyrin Centre de recherche en Acquisition et Traitement de l’Image pour la Santé (CREATIS) Centre National de la Recherche Scientifique Unité Mixte de Recherche 5220—Institut National de la Santé et de la Recherche Médicale Unité 1044—Université Lyon 1—Institut National des Sciences Appliquées de Lyon Lyon France Centre de recherche en Acquisition et Traitement de l’Image pour la Santé (CREATIS) Centre National de la Recherche Scientifique Unité Mixte de Recherche 5220—Institut National de la Santé et de la Recherche Médicale Unité 1044—Université Lyon 1—Institut National des Sciences Appliquées de Lyon Lyon France European Synchrotron Radiation Facility Grenoble France

Phase imaging coupled to micro-tomography acquisition has emerged as a powerful tool to investigate specimens in a non-destructive manner. While the intensity data can be acquired and recorded, the phase information of the signal has to be “retrieved” from the data modulus only. Phase retrieval is an ill-posed non-linear problem and regularization techniques including a priori knowledge are necessary to obtain stable solutions. Several linear phase recovery methods have been proposed and it is expected that some limitations resulting from the linearization of the direct problem will be overcome by taking into account the non-linearity of the phase problem. To achieve this goal, we propose and evaluate a non-linear algorithm for in-line phase micro-tomography based on an iterative landweber method with an analytic calculation of the Fréchet derivative of the phase-intensity relationship and of its adjoint. The algorithm was applied in the projection space using as initialization the linear mixed solution. The efficacy of the regularization scheme was evaluated on simulated objects with a slowly and a strongly varying phase. Experimental data were also acquired at ESRF using a propagation-based X-ray imaging technique for the given pixel size 0.68 μm. Two regularization scheme were considered: first the initialization was obtained without any prior on the ratio of the real and imaginary parts of the complex refractive index and secondly a constant a priori value was assumed on ?. The tomographic central slices of the refractive index decrement were compared and numerical evaluation was performed. The non-linear method globally decreases the reconstruction errors compared to the linear algorithm and is achieving better reconstruction results if no prior is introduced in the initialization solution. For in-line phase micro-tomography, this non-linear approach is a new and interesting method in biomedical studies where the exact value of the a priori ratio is not known.

关键词： Phase Retrieval In-Line Phase Tomography Inverse Problems Non-Linear Problem Non-Linear Optimization Fréchet derivative Coherent Imaging Fresnel Diffraction Phase Contrast X-Ray Imaging

Current hypotheses to explain genetic chaos under the sea

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Current Zoology 2016年第6期62卷 551-566页

作者： Bjarki ELDON Florentine RIQUET Jon YEARSLEY Didier JOLLIVET Thomas BROQUET Museum fur Naturkunde Berlin Leibniz Institut fur Evolutionsund Biodiversitatsforschung Berlin 10115 Germany Universite Montpellier 2 Place Eugene Bataillon 34095 Mentpellier Cedex 5 France ISEM - CNRS UMR 5554 SMEL 2 rue des Chantiers SAte 34200 France School of Biology and Environmental Science and UCD Earth institute University College Dublin Belfield Dublin 4 Ireland Centre national de la recherche scientifique Team Adaptation and Biology of Invertebrates in Extreme Environments Station Biologique de Roscoff Roscoff 29680 France Sorbonne Universites Universite Pierre et Marie Curie Unite Mixte de Recherche 7144 Station Biologique de Roscoff Roscoff 29680 France Centre national de la recherche scientifique Team Diversity and Connectivity of Coastal Marine Landscapes Station Biologique de Roscoff Roscoff 29680 France

Chaotic genetic patchiness （CGP） refers to surprising patterns of spatial and temporal genetic structure observed in some marine species at a scale where genetic variation should be efficiently homogenized by gene flow via larval dispersal. Here we review and discuss 4 mechanisms that could generate such unexpected patterns： selection, sweepstakes reproductive success, collective dispersal, and temporal shifts in local population dynamics. First, we review examples where genetic differentiation at specific loci was driven by diversifying selection, which was historically the first process invoked to explain CGP. Second, we turn to neutral demographic processes that may drive genome-wide effects, and whose effects on CGP may be enhanced when they act together. We discuss how sweepstakes reproductive success accelerates genetic drift and can thus generate genetic structure, provided that gene flow is not too strong. Collective dispersal is another mechanism whereby genetic structure can be maintained regardless of dispersal intensity, because it may prevent larval cohorts from becoming entirely mixed. Theoretical analyses of both the sweepstakes and the collective dispersal ideas are presented. Finally, we discuss an idea that has received less attention than the other ones just mentioned, namely temporal shifts in local population dynamics.

关键词： asynchronous population dynamics chaotic genetic patchiness collective dispersal kin aggregation larval dispersal multiple-merger coalescent sweepstakes reproductive success.

Impact of high-fat diet and vitamin D_3 supplementation on aortic stenosis establishment in waved-2 epidermal growth factor receptor mutant mice

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Journal of Integrative Medicine 2019年第2期17卷 107-114页

作者： Bérénice Colleville Nicolas Perzo Guillaume Avinée Ana?s Dumesnil Frederic Ziegler Paul Billoir Hélène Eltchaninoff Vincent Richard Eric Durand department of Biology Institut National de la Santé et de la Recherche Médicale U1096 (Endothélium Valvulopathies et Insuffisance Cardiaque) Normandie University Fédération Hospitalo-Universitaire REMOdeling in Valvulopathy and Heart Failure department of Cardiology Rouen University Hospital department of Biology Institut National de la Santé et de la Recherche Médicale U1073 (Nutrition Inflammation et Dysfonction de l’axe Intestin-Cerveau) Normandie University institute for Clinical Biology-General Biochemistry Unit Rouen University Hospital department of Vascular Hemostasis Rouen University Hospital

Objective: The use of animal models of aortic stenosis(AS) remains essential to further elucidate its pathophysiology and to evaluate new therapeutic strategies. The waved-2 mouse AS model has been proposed;data have indicated that while aortic regurgitation(AR) is effectively induced, development of AS is *** aimed to evaluate the effect of high-fat diet(HFD) and vitamin D_3 supplementation in this ***: HFD and subcutaneous vitamin D_3 injections were initiated at the age of 6 weeks until the age of 6(n = 16, 6-month treatment group) and 9(n = 11, 9-month treatment group) months. Twelve waved-2 mice without supplementation were used as control. Echocardiography was performed at 3, 6 and 9 months. Blood serum analysis(calcium, 1,25(OH)_2D_3 and cholesterol), histology and immunohistochemistry(CD-31, CD-68 and osteopontin) were evaluated at the end of the experiment(6 or 9 months).Results: Total cholesterol and 1,25(OH)_2D_3 were significantly increased relative to the control group. HFD and vitamin D_3 supplementation did result in improvements to the model, since AS was only detected in 6(15.3%) mice(2 in the 3 groups) and AR was developed in the remaining animals. Echocardiographic parameters, fibrosis, thickness, inflammation and valvular calcification, were not significantly different between the 6-month treatment and control groups. Similar results were also observed in the 9-month treatment ***: These results suggest that HFD and vitamin D_3 supplementation have no effect in the waved-2 mouse model. This model essentially mimics AR and rarely AS. Further studies are needed to find a reliable animal model of AS.

关键词： Experimental model Epidermal growth factor receptor Vitamin D3 High-fat diet Aortic stenosis Aortic regurgitation

Electrochemical Activation-Induced Structural Transformation in Ni(OH)_(2)/Ti_(3)C_(2)T_(x)/NF Systems with Enhanced Electrochemical Performance for Hybrid Supercapacitors

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Energy & Environmental Materials 2024年第4期7卷 277-284页

作者： Chuming Xu Lu Dai Yiming Zhao Shuang Li Yapan Wu Xueqian Wu Gaixia Zhang Shuhui Sun Dongsheng Li College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang 443002China Hubei Three Gorges laboratory Yichang 443007China department of Electrical Engineering École de Technologie Supérieure(ÉTS)MontréalQuébec H3C 1K3Canada institut national de la recherche scientifique(INRS) CentreÉnergie Matériaux TélécommunicationsVarennesQuébec J3X 1P7Canada

Exploring a novel strategy for large-scale production of battery-type Ni(OH)_(2)-based composites,with excellent capacitive performance,is still greatly ***,we developed a facile and cost-effective strategy to in situ grow a layer of Ni(OH)_(2)/Ti_(3)C_(2)T_(x)composite on the nickel foam(NF)collector,where Ti_(3)C_(2)T_(x)is not only a conductive component,but also a catalyst that accelerates the oxidation of NF to Ni(OH)_(2).detailed analysis reveals that the crystallinity,morphology,and electronic structure of the integrated electrode can be tuned via the electrochemical activation,which is beneficial for improving electrical conductivity and redox *** expected,the integrated electrode shows a specific capacity of 1.09 C cm^(-2)at 1 mA cm^(-2)after three custom activation cycles and maintains 92.4%of the initial capacity after 1500 ***,a hybrid supercapacitor composed of Ni(OH)_(2)/Ti_(3)C_(2)T_(x)/NF cathode and activated carbon anode provides an energy density of 0.1 mWh cm^(-2)at a power density of 0.97 mW cm^(-2),and excellent cycling stability with about 110%capacity retention rate after 5000 *** work would afford an economical and convenient method to steer commercial Ni foam into advanced Ni(OH)_(2)-based composite materials as binder-free electrodes for hybrid supercapacitors.

关键词： electrochemical activation hybrid supercapacitors Ni(OH)_(2) Ti_(3)C_(2)T_(x)