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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 389-401页

作者： Adolfo Foriero Filippo Santucci de Magistris Giovanni Fabbrocino Département de génie civil et de génie des eaux Pavillon Adrien-PouliotUniversitéLavalQuébecCanada Dipartimento di Bioscienze e Territorio Universitàdegli Studi del MoliseCampobassoItaly Construction Technologies Institute National Research CouncilITC-CNRL’AquilaItaly

This work presents a novel approach to the dynamic response analysis of a Euler-Bernoulli beam resting on a Winkler soil model and subjected to an impact *** approach considers that damping has much less importance in controlling the maximum response to impulsive loadings because the maximum response is reached in a very short time,before the damping forces can dissipate a significant portion of the energy input into the *** development of two sine series solutions,relating to different types of impulsive loadings,one involving a single concentrated force and the other a distributed line load,are *** study revealed that when a simply supported Euler-Bernoulli beam,resting on a Winkler soil model,is subject to an impact load,the resulting vertical displacements,bending moments and shear forces produced along the span of the beam are considerably *** particular,the quantification of this effect is best observed,relative to the corresponding static solution,via an amplification *** computed impact amplification factors,for the sub-grade moduli used in this study,were in magnitude greater than 2,thus confirming the multiple-degree-of-freedom nature of the problem.

关键词： beam-Winkler-soil model sub-grade moduli impact load impact distributed line load dynamic solution impact amplification factor

Stepping up after spinal cord injury:negotiating an obstacle during walking

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Neural Regeneration Research 2025年第7期20卷 1919-1929页

作者： Alain Frigon Charly G.Lecomte department of Pharmacology-Physiology Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

Every day walking consists of frequent voluntary modifications in the gait pattern to negotiate *** spinal cord injury,stepping over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including the parietal cortex,premotor cortex,and motor *** information and planning are transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiology obstacle negotiation spinal cord injury

A level line of the Gaussian free field with measure-valued boundary conditions

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Science China Mathematics 2024年第2期67卷 367-404页

作者： Titus Lupu Hao Wu Laboratoire de Probabilités Statistique et ModélisationSorbonne Universitéand UniversitéParis CitéCNRSParis F-75005France Yau Mathematical Sciences Center Tsinghua UniversityBeijing 100084China

In this article, we construct samples of Schramm-Loewner-evolution-like curves out of samples ofthe conformal loop ensemble and Poisson point processes of Brownian excursions. We show that the laws of thesecurves depend continuously on the intensity measure of the Brownian excursions. Using such a construction ofcurves, we extend the notion of level lines of the Gaussian free field to the case where the boundary conditionis measure-valued.

关键词： Schramm-Loewner evolution conformal loop ensemble Brownian excursion Gaussian free field

A novel multi-channel porous structure facilitating mass transport towards highly efficient alkaline water electrolysis

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Journal of Energy Chemistry 2024年第6期93卷 511-518,I0013页

作者： Xinge Jiang Vasileios Kyriakou Chen Song Xianbin Wang Sophie Costil Chunming deng Taikai Liu Tao Jiang Hanlin Liao universitéde technologie de Belfort Montbéliard Centre national de la recherche scientifiqueLaboratoire Interdisciplinaire Carnot de BourgogneBelfort 90010France department of Chemical Engineering Engineering and Technology Institute Groningen(ENTEG)University of GroningenGroningen 9747 AGThe Netherlands The Institute of New Materials Guangdong Academy of ScienceGuangzhou 510650GuangdongChina

An advantageous porous architecture of electrodes is pivotal in significantly enhancing alkaline water electrolysis(AWE)efficiency by optimizing the mass transport *** effect becomes even more pronounced when aiming to achieve elevated current ***,we employed a rapid and scalable laser texturing process to craft novel multi-channel porous ***,the obtained electrodes exhibit the lowest Tafel slope of 79 mV dec^(-1)(HER)and 49 mV dec^(-1)(OER).As anticipated,the alkaline electrolyzer(AEL)cell incorporating multi-channel porous electrodes(NP-LT30)exhibited a remarkable improvement in cell efficiency,with voltage drops(from 2.28 to 1.97 V)exceeding 300 mV under 1 A cm^(-1),compared to conventional perforated Ni plate *** enhancement mainly stemmed from the employed multi-channel porous structure,facilitating mass transport and bubble dynamics through an innovative convection mode,surpassing the traditional convection ***,the NP-LT30-based AEL cell demonstrated exceptional durability for 300 h under 1.0 A cm^(-2).This study underscores the capability of the novel multi-channel porous electrodes to expedite mass transport in practical AWE applications.

关键词： Alkaline water electrolysis Mass transport Bubble dynamics Innovative convection mode Multi-channel porous structure

Collisionless shock acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves

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Matter and Radiation at Extremes 2024年第2期9卷 12-25页

作者： J.-R.Marquès L.Lancia P.Loiseau P.Forestier-Colleoni M.Tarisien E.Atukpor V.Bagnoud C.Brabetz F.Consoli J.Domange F.Hannachi P.Nicolaï M.Salvadori B.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance CEA DAMDIF91297 Arpajon CedexFrance universitéParis-Saclay CEALMCE91680 Bruyères-le-ChatelFrance CENBG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany university of Darmstadt Schloßgartenstr.764289 DarmstadtGermany ENEA Fusion and Technologies for Nuclear Safety department C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly CELIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance universitéParis-Saclay CEALIDYL91191 Gif-sur-YvetteFrance

We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[Marquès et al.,*** 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas *** tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by Coulomb *** the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are *** forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(CSA).The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe *** refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma *** with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas *** parameters are in good agreement with those required for CSA.

关键词： acceleration hydrodynamic collision

Disorder effects in NbTiN superconducting resonators

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Chinese Physics B 2024年第2期33卷 482-486页

作者：吕伟涛支强胡洁李婧史生才 Purple Mountain Observatory Chinese Academy of SciencesNanjing 210034China GEPI Observatoire de ParisPSL UniversitéCNRSParis 75014France

Disordered superconducting materials like NbTiN possess a high kinetic inductance fraction and an adjustable critical temperature, making them a good choice for low-temperature detectors. Their energy gap(D), critical temperature(T_(c)),and quasiparticle density of states(QDOS) distribution, however, deviate from the classical BCS theory due to the disorder effects. The Usadel equation, which takes account of elastic scattering, non-elastic scattering, and electro–phonon coupling,can be applied to explain and describe these deviations. This paper presents numerical simulations of the disorder effects based on the Usadel equation to investigate their effects on the △, Tc, QDOS distribution, and complex conductivity of the NbTiN film. Furthermore, NbTiN superconducting resonators with coplanar waveguide(CPW) structures are fabricated and characterized at different temperatures to validate our numerical simulations. The pair-breaking parameter α and the critical temperature in the pure state T_(c)^(P) of our NbTiN film are determined from the experimental results and numerical simulations. This study has significant implications for the development of low-temperature detectors made of disordered superconducting materials.

关键词： effects of disorder NbTiN superconducting film Usadel equation complex conductivity superconducting resonator

Bound and Resonating Multiquark Configurations

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Chinese Physics Letters 2024年第8期41卷 8-12页

作者： Jean-Marc Richard Institut de Physique des 2 Infinis de Lyon universit′e Claude Bernard(Lyon 1) CNRS-IN2P34 rue Enrico Fermi69622 VilleurbanneFrance

We review the predictions of quark models for multiquark configurations that are bound or resonant states,and compare different methods for estimating the properties of resonances.

关键词： quark Configuration resonant

Does photobiomodulation require glucose to work effectively?

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Neural Regeneration Research 2024年第5期19卷 945-946页

作者： Jaimie Hoh Kam John Mitrofanis universitéGrenoble Alpes Fonds de Dotation ClinatecGrenobleFrance university College London Institute of OphthalmologyUK

A main requirement for cells to function normally is the availability of ***,available either direct from circulation or storage,is converted to the essential energy that cells need to drive critical intrinsic *** cells are deprived of glucose,they become dysfunctional and suffer ***,the use of specific wavelengths of light on body tissues,has been shown to promote,through small organelles called mitochondria,the metabolism of glucose to make energy for cells;this energy can be used to improve cell function and *** this perspective,we hypothesize that the availability of glucose is central to the core mechanism of photobiomodulation;that photobiomodulation is at its most efficient in stimulating mitochondrial activity and improving cell function when there is glucose readily available.

关键词： metabolism distress stimulating

Numerical Study of Semidiscrete Penalty Approach for Stabilizing Boussinesq System with Localized Feedback Control

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Annals of Applied Mathematics 2024年第2期 191-218页

作者： Mejdi Azaiez Kévin Le Balc'h université de Bordeaux Inria Sorbonne Université Université de Paris CNRS Laboratoire Jacques-Louis Lions

We investigate the numerical approximation for stabilizing the semidiscrete linearized Boussinesq system around an unstable stationary *** is attained through internal feedback controls applied to the velocity and temperature equations, localized within an arbitrary open subset. This study follows the framework presented in [14], considering the continuous linearized Boussinesq system. The primary objective is to explore the penalizationbased approximation of the free divergence condition in the semidiscrete case and provide a numerical validation of these results in a two-dimensional setting.

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Factors associated with decreased compliance after on-site extracorporeal membrane oxygenation cannulation for acute respiratory distress syndrome:A retrospective,observational cohort study

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Journal of Intensive Medicine 2024年第2期4卷 194-201页

作者： Sylvain Le Pape Florent Joly François Arrivé Jean-Pierre Frat Maeva Rodriguez Maïa Joos Laura Marchasson Mathilde Wairy Arnaud WThille Rémi Coudroy Centre Hospitalier universitaire de Poitiers Service de Médecine Intensive RéanimationPoitiersFrance INSERM Centre d'Investigation Clinique 1402 IS-ALIVE Research GroupUniversitéde PoitiersPoitiersFrance

Background Extracorporeal membrane oxygenation(ECMO)for acute respiratory distress syndrome(ARDS)is systematically associated with decreased respiratory system compliance(CRS).It remains unclear whether transportation to the referral ECMO center,changes in ventilatory mode or settings to achieve ultra-protective ventilation,or the natural evolution of ARDS drives this change in respiratory ***,we assessed the precise moment when CRS decreases after ECMO cannulation and identified factors associated with decreased *** To rule out the effect of transportation and the different modes of ventilation on CRS,we conducted a retrospective,single-center,observational cohort study from January 2013 to May 2020,on 22 patients with severe ARDS requiring on-site ECMO and ventilated in pressure-controlled mode to achieve ultra-protective *** was assessed at different time points ranging from 12 h before ECMO cannulation to 72 h after ECMO *** primary outcome was the relative change in CRS between 3 h before and 3 h after ECMO *** secondary outcomes included variables associated with the relative changes in CRS within the first 3 h after ECMO cannulation and the relative changes in CRS at each time *** CRS decreased within the first 3 h after ECMO cannulation(−28.3%,95%confidence interval[CI]:−38.8 to−17.9,Pdecrease was mild before and after these first 3 h after ECMO *** achieve ultra-protective ventilation,respiratory rate decreased in the mean by–13 breaths/min(95%CI:−15 to−11)and driving pressure by−8.3 cmH2O(95%CI:−11.2 to−5.3),resulting in decreased tidal volume by−3.3 mL/kg of predicted body weight(95%CI:−3.9 to−2.6)as compared to before ECMO cannulation(Pdecreased CRS after ECMO cannulation,whereas neither respiratory rate,positive end-expiratory pr

关键词： Acute respiratory distress syndrome Extracorporeal membrane oxygenation Driving pressure Respiratory compliance