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Laser-induced plasma formation in water with up to 400 mJ double-pulse LIBS

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Plasma Science and Technology 2024年第1期26卷 93-100页

作者： Marion HENKEL Michelle SIEMENS Ralf METHLING Benjamin EMDE Jörg HERMSDORF Steffen FRANKE Diego GONZALEZ Leibniz Institute for Plasma Science and Technology(inp) Felix-Hausdorff-Straße 2Greifswald 17489Germany Laser Zentrum Hannover e.V.(LZH) Hollerithallee 8Hannover 30419Germany

Double-pulse LIBS is a promising technique for deep-sea applications.LIBS measurements in shallow water with up to 400 mJ each pulse were done to select laser parameters which promote optimized spectral line emission from plasma even at elevated pressures,where line broadening until loss of most of the spectral information can occur.Optical emission spectroscopy,using a Czerny-Turner spectrometer,has been applied to investigate the dependence of the emitted radiation on laser parameters and hydrostatic pressure.It has been found,that higher laser pulse energies,especially with short pulse delay as required in high water pressure,can also have an adverse effect on the measured spectrum.

关键词： double-pulse LIBS underwater plasma formation emission spectrosocpy

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Dynamics of Low-Viscosity Liquids Interface in an Unevenly Rotating Vertical Layer

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Fluid Dynamics & Materials Processing 2024年第4期20卷 693-703页

作者： Victor Kozlov Vladimir Saidakov Nikolai Kozlov Laboratory of Vibrational Hydromechanics Perm State Humanitarian Pedagogical UniversityPerm614990Russia Institut de Mécanique des Fluides de Toulouse Toulouse INPToulouse31400France

The behavior of two immiscible low-viscosity liquids differing in density and viscosity in a vertical flat layer undergoing modulated rotation is experimentally studied.The layer has a circular axisymmetric boundary.In the absence of modulation of the rotation speed,the interphase boundary has the shape of a short axisymmetric cylinder.A new effect has been discovered,under the influence of rotation speed modulation,the interface takes on a new dynamic equilibrium state.A more viscous liquid covers the end boundaries of the layer in the form of thin films,which have the shape of round spots of almost constant radius;with increasing amplitude of the velocity modulation,the wetting boundary expands.It is found that upon reaching the critical amplitude of oscillations,the film of a viscous liquid loses stability,and the outer edge of the wetting spot collapses and takes on a feathery structure.It is shown that this threshold is caused by the development of the Kelvin-Helmholtz oscillatory instability of the film.The spreading radius of a spot of light viscous liquid and its stability are studied depending on the rotation rate,amplitude,and frequency of rotation speed modulation.The discovered averaged effects are determined by different oscillatory interaction of fluids with the end-walls of the cell,due to different viscosities.The effect of films forming can find application in technological processes to intensify mass transfer at interphase boundaries.

关键词： Rotation oscillations immiscible fluids contact line interface film dynamic equilibrium Nomenclature frot

A transcriptional cascade mediated by two APETALA2 family members orchestrates carotenoid biosynthesis in tomato

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Journal of Integrative Plant Biology 2024年第6期66卷 1227-1241页

作者： Xiaoqing He Kaidong Liu Yi Wu Weijie Xu Ruochen Wang Julien Pirrello Mondher Bouzayen Mengbo Wu Mingchun Liu Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life Sciences Sichuan University Life Science and Technology School Lingnan Normal University Laboratoire de Recherche en Sciences Végétales—Génomique et Biotechnologie des Fruits—UMR5546 Université de ToulouseCNRS UPSToulouse-INP

Carotenoids are important nutrients for human health that must be obtained from plants since they cannot be biosynthesized by the human body. Dissecting the regulatory mechanism of carotenoid metabolism in plants represents the first step toward manipulating carotenoid contents in plants by molecular design breeding. In this study, we determined that SlAP2c, an APETALA2(AP2) family member, acts as a transcriptional repressor to regulate carotenoid biosynthesis in tomato(Solanum lycopersicum).Knockout of SlAP2c in both the “Micro Tom” and“Ailsa Craig” backgrounds resulted in greater lycopene accumulation, whereas overexpression of this gene led to orange-ripe fruit with significantly lower lycopene contents than the wild type. We established that SlAP2c represses the expression of genes involved in lycopene biosynthesis by directly binding to the cis-elements in their promoters.Moreover, SlAP2c relies on its EAR motif to recruit the co-repressors TOPLESS(TPL)2/4 and forms a complex with histone deacetylase(had)1/3, thereby reducing the histone acetylation levels of lycopene biosynthesis genes. Furthermore, SlAP2a, a homolog of SlAP2c, acts upstream of SlAP2c and alleviates the SlAP2c-induced repression of lycopene biosynthesis genes by inhibiting SlAP2c transcription during fruit ripening. Therefore, we identified a transcriptional cascade mediated by AP2 family members that regulates lycopene biosynthesis during fruit ripening in tomato, laying the foundation for the manipulation of carotenoid metabolism in plants.

关键词： APETALA2 family members carotenoid biosynthesis tomato transcriptional cascade

Influence of manufacturing process-induced geometrical defects on the energy absorption capacity of polymer lattice structures

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Defence Technology（防务技术） 2024年第5期35卷 47-59页

作者： Alexandre Riot Enrico Panettieri Antonio Cosculluela Marco Montemurro Universite de Bordeaux Arts et Metiers Institute of TechnologyCNRSINRABordeaux INPHESAM UniversiteI2M UMR 5295F-33405 TalenceFrance French Atomic Energy Commission Route des GargailsCedexF-33114Le BarpFrance

Modern additive manufacturing processes enable fabricating architected cellular materials of complex shape,which can be used for different purposes.Among them,lattice structures are increasingly used in applications requiring a compromise among lightness and suited mechanical properties,like improved energy absorption capacity and specific stiffness-to-weight and strength-to-weight ratios.A dedicated modeling strategy to assess the energy absorption capacity of lattice structures under uni-axial compression loading is presented in this work.The numerical model is developed in a non-linear framework accounting for the strain rate effect on the mechanical responses of the lattice structure.Four geometries,i.e.,cubic body centered cell,octet cell,rhombic-dodecahedron and truncated cuboctahedron 2+,are investigated.Specifically,the influence of the relative density of the representative volume element of each geometry,the strain-rate dependency of the bulk material and of the presence of the manufacturing process-induced geometrical imperfections on the energy absorption capacity of the lattice structure is investigated.The main outcome of this study points out the importance of correctly integrating geometrical imperfections into the modeling strategy when shock absorption applications are aimed for.

关键词： Lattice structures Architected cellular materials Dynamic simulation Energy absorption Geometrical imperfection Additive manufacturing

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Deterministic and probabilistic analysis of great-depth braced excavations:A 32 m excavation case study in Paris

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1505-1521页

作者： Tingting Zhang Julien Baroth Daniel Dias Khadija Nejjar Université Grenoble Alpes CNRSGrenoble INP3SRGrenoble38000France Antea Group Antony92160France School of Automotive and Transportation Engineering Hefei University of TechnologyHefei23009China Terrasol 42-52 Quai de la RapéeParis75012France

The Fort d’Issy-Vanves-Clamart(FIVC)braced excavation in France is analyzed to provide insights into the geotechnical serviceability assessment of excavations at great depth within deterministic and probabilistic frameworks.The FIVC excavation is excavated at 32 m below the ground surface in Parisian sedimentary basin and a plane-strain finite element analysis is implemented to examine the wall deflections and ground surface settlements.A stochastic finite element method based on the polynomial chaos Kriging metamodel(MSFEM)is then proposed for the probabilistic analyses.Comparisons with field measurements and former studies are carried out.Several academic cases are then conducted to investigate the great-depth excavation stability regarding the maximum horizontal wall deflection and maximum ground surface settlement.The results indicate that the proposed MSFEM is effective for probabilistic analyses and can provide useful insights for the excavation design and construction.A sensitivity analysis for seven considered random parameters is then implemented.The soil friction angle at the excavation bottom layer is the most significant one for design.The soil-wall interaction effects on the excavation stability are also given.

关键词： Braced deep excavation Soil-wall interaction Stochastic finite element method Horizontal wall deflection Settlement Failure probability

Small holes,big impact:Stomata in plant–pathogen–climate epic trifecta

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Molecular Plant 2024年第1期17卷 26-49页

作者： Shuguo Hou Olivier Rodrigues Zunyong Liu Libo Shan Ping He Peking University Institute of Advanced Agricultural Sciences Shandong Laboratory of Advanced Agriculture Sciences in WeifangWeifangShandong 261325China School of Municipal&Environmental Engineering Shandong Jianzhu UniversityJinanShandong 250101China Unitéde Recherche Physiologie Pathologie et Génétique VégétalesUniversitéde Toulouse Midi-PyrénéesINP-PURPAN31076 ToulouseFrance Department of Molecular Cellularand Developmental BiologyUniversity of MichiganAnn ArborMI 48109USA

The regulation of stomatal aperture opening and closure represents an evolutionary battle between plants and pathogens,characterized by adaptive strategies that influence both plant resistance and pathogen virulence.The ongoing climate change introduces further complexity,affecting pathogen invasion and host immunity.This review delves into recent advances on our understanding of the mechanisms governing immunity-related stomatal movement and patterning with an emphasis on the regulation of stomatal opening and closure dynamics by pathogen patterns and host phytocytokines.In addition,the review explores how climate changes impact plant–pathogen interactions by modulating stomatal behavior.In light of the pressing challenges associated with food security and the unpredictable nature of climate changes,future research in this field,which includes the investigation of spatiotemporal regulation and engineering of stomatal immunity,emerges as a promising avenue for enhancing crop resilience and contributing to climate control strategies.

关键词： stomatal movement stomatal patterning plant resistance pathogen virulence apoplastic immunity and climate change

Interaction of photons with silver and indium nuclei at energies up to 20 MeV

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Chinese Physics C 2024年第2期48卷 135-140页

作者： J.H.Khushvaktov M.A.Demichev D.L.Demin S.A.Evseev M.I.Gostkin V.V.Kobets F.A.Rasu-lova S.V.Rozov E.T.Ruziev A.A.Solnyshkin T.N.Tran E.A.Yakushev B.S.Yuldashev Joint Institute for Nuclear Research(JINR) DubnaRussia Institute of Nuclear Physics of the Academy of Sciences of the Republic of Uzbekistan(inp ASRU) TashkentUzbekistan Institute of Physics of the Vietnam Academy of Science and Technology(IP VAST) HanoiVietnam

The yields of photonuclear reactions in the 107Ag,113In,and 115In nuclei were measured.Monte Carlo simulations were performed using the Geant4 code,and the results were compared with the experimental values.The isomeric ratios of the yields in the reactions 107Ag(γ,n)106m,gAg and 113In(γ,m)112m,gIn were determined,and the cross sections for the reactions 107Ag(γ,n)106gAg and 107Ag(γ,2n)105Ag at an energy of 20 MeV were calculated based on the experimental data.

关键词： 107Ag(γ,n)10mgAg and I13In(γ,n)12m-2In reactions cross section yield isomeric ratio simula-tion Geant4 TALYS

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Preclinical and clinical evidence of the association of colibactinproducing Escherichia coli with anxiety and depression in colon cancer

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World Journal of Gastroenterology 2024年第21期30卷 2817-2826页

作者： Fabien Rondepierre Maëva Meynier Johan Gagniere Vincent Deneuvy Anissa Deneuvy Gwenaelle Roche Elodie Baudu Bruno Pereira Richard Bonnet Nicolas Barnich Frédéric Antonio Carvalho Denis Pezet Mathilde Bonnet Isabelle Jalenques Service de Psychiatrie de l’Adulte A et Psychologie Médicale CHU Clermont-FerrandClermont-Ferrand 63000France M2iSH UMR 1071INSERMUniversity of Clermont AuvergneINRAE USC 1382Clermont-Ferrand 63001France NeuroDol UMR 1107INSERMUniversity of Clermont AuvergneClermont-Ferrand 63001France Department of Digestive Surgery CHU de Clermont-FerrandClermont-Ferrand 63001France Biostatistics Unit Department of Clinical Research and InnovationCHU Clermont-FerrandClermont-Ferrand 63000France Department of Bacteriology CHU de Clermont-FerrandClermont-Ferrand 63001France UniversitéClermont Auvergne INPCNRSClermont Auvergne Institut PascalClermont-Ferrand 63000France

BACKGROUND The association between the intestinal microbiota and psychiatric disorders is becoming increasingly apparent.The gut microbiota contributes to colorectal carcinogenesis(CRC),as demonstrated with colibactin-producing Escherichia coli(CoPEC).AIM To evaluate the association between CoPEC prevalence and anxiety-and depressive-like behaviors with both preclinical and clinical approaches.METHODS Patients followed after a CRC surgery and for whom the prevalence of CoPEC has been investigated underwent a psychiatric interview.Results were compared according to the CoPEC colonization.In parallel C57BL6/J wild type mice and mice with a CRC susceptibility were chronically infected with a CoPEC strain.Their behavior was assessed using the Elevated Plus Maze test,the Forced Swimming Test and the Behavior recognition system PhenoTyper®.RESULTS In a limited cohort,all patients with CoPEC colonization presented with psychiatric disorders several years before cancer diagnosis,whereas only one patient(17%)without CoPEC did.This result was confirmed in C57BL6/J wildtype mice and in a CRC susceptibility mouse model(adenomatous polyposis colimultiple intestinal neoplasia/+).Mice exhibited a significant increase in anxiety-and depressive-like behaviors after chronic infection with a CoPEC strain.CONCLUSION This finding provides the first evidence that CoPEC infection can induce microbiota-gut-brain axis disturbances in addition to its procarcinogenic properties.

关键词： Colorectal cancer Colibactin Escherichia coli Colibactin-producing Escherichia coli Inflammation Anxiety Depression Behavior

Preliminary Study of Chemical Elements Distribution in Petroleum Source Rocks Donga and Yogou Formations of the Termit Sedimentary Basin (Est-Niger)

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Journal of Minerals and Materials Characterization and Engineering 2024年第1期12卷 49-62页

作者： Alassane Ibrahim Maman Bachir Abdoulaye Dan Makaou Oumarou Baraou Idi Souley Kouakou Alponse Yaou Abdoulwahid Sani Department of Fossil Energy University of Agadez (UAZ) Agadez Niger Civil Engineering Geosciences and Geographic Sciences Laboratory Institut National Polytechnique Félix Houphou&#235t Boigny (INP-HB) Yamoussoukro C&#244te d’Ivoire Department of Geology University of Agadez (UAZ) Agadez Niger

XRF and EDX analyses were carried out on 18 batches of representative raw samples to determine the distribution of major chemical elements in the petroleum source rocks of Donga and Yogou formations of Termit sedimentary basin. The chemical composition of these formations is dominated by silicon (Si), aluminum (Al) and iron (Fe). This is consistent with the oxide composition, which is also dominated by silicon oxide (SiO2), aluminum oxide (Al2O3) and iron monoxide (FeO). No less important chemical elements are calcium (Ca), potassium (K), sulfur (S), titanium (Ti), magnesium (Mg), manganese (Mn) and barium (Ba), as well as some of their oxides. All these major chemical elements are carried by silicate detrital minerals associated with pyrite and goethite and/or clay minerals such as kaolinite and interstratified illite, smectite and chlorite. This trend is illustrated by the values of the Si/Al and SiO2/Al2O3 ratios.

关键词： Distribution Major Elements Source Rocks Donga Formation Yogou Formation Termit Basin