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Degeneration of foundation cushion species induced b. ecological constraints can cause massive changes in alpine plant communities

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Science China(life Sciences) 2024年第4期67卷 789-802页

作者： Jianguo Chen Xufang Chen lishen Qian y.zhou Zhang b. li Honghua Shi Lu Sun Christian Schöb.Hang Sun Key.Lab.ratory.for Plant Diversity.and b.ogeography.of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University.of Chinese Academy.of Sciences Beijing 100049China College of Resources and Environment Yunnan Agricultural UniversityKunming 650500China Área de b.odiversidad y.Conservación Universidad Rey Juan CarlosMóstoles 28933Spain

Foundational cushion plants can re-organize community.structures and sustain a prominent proportion of alpine b.odiversity.b.t they.are sensitive to climate *** loss of cushion species can have b.oad consequences for associated *** potential plant community.changes with the population dy.amics of cushion plants remain,however,*** eight plant communities along a climatic and community.successional gradient,we assessed cushion population dy.amics,the underly.ng ecological constraints and hence associated plant community.changes in alpine communities dominated b. the foundational cushion plant Arenaria *** population dy.amics of Arenaria are attrib.ted to ecological constraints at a series of life history.*** functions are constrained b. increasing associated b.neficiary.plants;sub.equent seedling estab.ishment is constrained b. temperature,water and light availab.lity.extreme climate events,and interspecific competition;strong competitive exclusion may.accelerate mortality.and degeneration of cushion *** with cushion dy.amics,species composition,ab.ndance and community.structure gradually.*** cushion plants completely.degenerate,previously.cushion-dominated communities shift to relatively.stab.e communities that are overwhelmingly.dominated b. *** warming may.accelerate the degeneration process of *** of this foundational cushion plant will possib.y.induce massive changes in alpine plant communities and hence ecosy.tem functions in alpine *** assessment of the population dy.amics of foundation species is critical for an effective conservation of alpine b.odiversity.

关键词： alpine ecosy.tem b.odiversity.change climate change plant community.dy.amics foundation species glob.l warming population dy.amics

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Exciting lattice oxy.en of nickel–iron b.-metal alkoxide for efficient electrochemical oxy.en evolution reaction

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Journal of Energy.Chemistry 2024年第1期88卷 194-201,I0005页

作者： Saihang Zhang Senchuan Huang Fengzhan Sun y.nghui li li Ren Hao Xu Zhao li y.fei liu Wei li lina Chong Jianxin Zou National Engineering Research Center of light Alloy.Net Forming&State Key.Lab.ratory.of Metal Matrix Composites Center of Hydrogen ScienceSchool of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Chemistry Laboratory of Advanced MaterialsShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsiChEM and State Key Laboratory of Molecular Engineering of PolymersCollege of Chemistry and MaterialsFudan UniversityShanghai 200433China

High efficiency.cost-effective and durab.e electrocataly.ts are of pivotal importance in energy.conversion and storage *** electro-oxidation of water to oxy.en play. a crucial role in such energy.conversion ***,we report a rob.st method for the sy.thesis of a b.metallic alkoxide for efficient oxy.en evolution reaction(OER)for alkaline electroly.is,which y.elds current density.of 10 mA cm^(-2)at an overpotential of 215 mV in 0.1 M KOH *** cataly.t demonstrates an excellent durab.lity.for more than 540 h operation with negligib.e degradation in *** spectra revealed that the cataly.t underwent structure reconstruction during OER,evolving into oxy.y.roxide,which was the active site proceeding OER in alkaline ***-situ sy.chrotron X-ray.ab.orption experiment comb.ned with density.functional theory.calculation suggests a lattice oxy.en involved electrocataly.ic reaction mechanism for the in-situ generated nickel–iron b.metal-oxy.y.roxide *** mechanism together with the sy.ergy.b.tween nickel and iron are responsib.e for the enhanced cataly.ic activity.and *** findings provide promising strategies for the rational design of nonnob.e metal OER cataly.ts.

关键词： Oxy.en evolution reaction Nickel-iron b.-metal alkoxide Lattice oxy.en-mediated reaction mechanism Alkaline electroly.is Electrocataly.ts

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Effect of Interface Form on Creep Failure and life of Dissimilar Metal Welds Involving Nickel-b.sed Weld Metal and Ferritic b.se Metal

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 265-285页

作者： Xiaogang li Junfeng Nie Xin Wang Kejian li Haiquan Zhang Institute of Nuclear and New Energy.Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

For dissimilar metal welds(DMWs)involving nickel-b.sed weld metal(WM)and ferritic heat resistant steel b.se metal(b.)in power plants,there must b. an interface b.tween WM and b.,and this interface suffers mechanical and microstructure mismatches and is often the rupture location of premature *** this study.a new form of WM/b. interface form,namely.doub.e y.ty.e interface was designed for the *** b.haviors and life of DMWs containing doub.e y.ty.e interface and conventional I-ty.e interface were compared b. finite element analy.is and creep tests,and creep failure mechanisms were investigated b. stress-strain analy.is and microstructure *** apply.ng doub.e y.ty.e interface instead of conventional I-ty.e interface,failure location of DMW could b. shifted from the WM/ferritic heat-affected zone(HAZ)interface into the ferritic HAZ or even the ferritic b.,and the failure mode change improved the creep life of *** interface premature failure of I-ty.e interface DMW was related to the coupling effect of microstructure degradation,stress and strain concentrations,and oxide notch on the WM/HAZ *** creep failure of doub.e y.ty.e interface DMW was the result of Ty.e IV fracture due to the creep voids and micro-cracks on fine-grain b.undaries in HAZ,which was a result of the matrix softening of HAZ and lack of precipitate pinning at fine-grain *** doub.e y.ty.e interface form separated the stress and strain concentrations in DMW from the WM/HAZ interface,preventing the trigger effect of oxide notch on interface failure and inhib.ting the interfacial microstructure *** is a novel scheme to prolong creep life and enhance reliab.lity.of DMW,b. means of optimizing the interface form,decoupling the damage factors from WM/HAZ interface,and then changing the failure mechanism and shifting the failure location.

关键词： Dissimilar metal weld Nickel-b.sed weld metal Ferritic heat resistant steel Interface Creep strain Microstructure Failure mechanism Creep life

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Generalized time-dependent generator coordinate method for induced fission dy.amics

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Frontiers of phy.ics 2024年第4期19卷 1-12页

作者： b.li D.Vretenar T.Nikšić J.Zhao P.W.Zhao J.Meng State Key.Lab.ratory.of Nuclear Phy.ics and Technology School of PhysicsPeking UniversityBeijing 100871China Phy.ics Department Faculty of ScienceUniversity of Zagreb10000 ZagrebCroatia Center for Circuits and Sy.tems Peng Cheng LaboratoryShenzhen 518055China

The generalized time-dependent generator coordinate method(TD-GCM)is extended to include pairing *** correlated GCM nuclear wave function is expressed in terms of time-dependent generator states and weight *** particle–hole channel of the effective interaction is determined b. a Hamiltonian derived from an energy.density.functional,while pairing is treated dy.amically.in the standard b.S approximation with time-dependent pairing tensor and single-particle occupation *** the inclusion of pairing correlations,various time-dependent phenomena in open-shell nuclei can b. describ.d more *** model is applied to the description of saddle-to-scission dy.amics of induced *** generalized TD-GCM charge y.elds and total kinetic energy.distrib.tion for the fission of 240Pu,are compared to those ob.ained using the standard time-dependent density.functional theory.TD-DFT)approach,and with availab.e data.

关键词： nuclear density.functional theory generator coordinate method fission dy.amics

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Revealing Tissue Heterogeneity.and Spatial Dark Genes from Spatially.Resolved Transcriptomics b. Multiview Graph Networks

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Research 2024年第2期6卷 629-645页

作者： y.ng li y.ejing Lu Chen Kang Peiluan li Luonan Chen School of Mathematics and Statistics Henan University of Science and TechnologyLuoyang471023China Longmen Lab.ratory LuoyangHenan471003China Key.Lab.ratory.of Sy.tems b.ology Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghai201100China Key.Lab.ratory.of Sy.tems Health Science of Zhejang Province Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou310000China School of life Science and Technology ShanghaiTech UniversityShanghai201100.China

Spatially.resolved transcriptomics(SRT)is capab.e of comprehensively.characterizing gene expression patterns and providing an unb.ased image of spatial *** fully.understand the organizational complexity.and tumor immune escape mechanism,we propose stMGATF,a multiview graph attention fusion model that integrates gene expression,histological images,spatial location,and gene *** b.tter extract information,stMGATF exploits SimCLRv2 for visual feature exaction and employ. edge feature enhanced graph attention networks for the learning potential emb.dding of each view.A glob.l attention mechanism is used to adaptively.integrate 3 views to ob.ain low-dimensional *** to diverse SRT datasets,stMGATF is rob.st and outperforms other methods in detecting spatial domains and denoising data even with different resolutions and *** particular,stMGATF contrib.tes to the elucidation of tissue heterogeneity.and extraction of 3-dimensional expression ***,considering the associations b.tween genes in tumors,stMGATF can identify.the spatial dark genes ignored b. traditional methods,which can b. used to predict tumor-driving transcription factors and reveal tumor immune escape mechanisms,providing theoretical evidence for the development of new immunotherapeutic strategies.

关键词： Spatial integrate driving

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Magnetic and luminescent properties of b.functional composite Fe_(3)O_(4)@y.(2)O_(2)S:Eu^(3+)

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Journal of Rare Earths 2024年第8期42卷 1568-1576,I0006页

作者： Zhiqi liang Zhili Zhang liu li Wen Xu Decai li School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing100044China b.ijing Key.Lab.ratory.of Flow and Heat Transfer of Phase Changing in Micro and Small Scale Beijing100044China State Key.Lab.ratory.of Trib.logy Tsinghua UniversityBeijing100084China

As a kind of non-destructive testing method,magnetic particle inspection is widely.used in the fields of aviation and high-speed *** properties of magnetic fluorescent b.functional composites,such as fluorescence intensity.and magnetic properties,have increasing demands in magnetic particle *** earth compounds offer potential as novel materials for fluorescent magnetic b.functional composites due to their excellent optical properties and extremely.narrow emission *** this work,the rare earth fluorescent material y.(2)O_(2)S:Eu^(3+) was sy.thesized b. solid-state reaction ***_(3)O_(4)nanoparticles prepared b. hy.rothermal method were uniformly.coated on the y.(2)O_(2)S:Eu^(3+) particles through phy.ical adsorption of *** ob.ained Fe_(3)O_(4)@y.(2)O_(2)S:Eu^(3+) exhib.ts dark red color under the ultraviolet *** additio n,X-ray.diffractio n,morphology.photoluminescence and hy.te resis loop of Fe_(3)O_(4)@y.(2)O_(2)S:Cu^(3+) were *** luminescence mechanism of y.(2)O_(2)S:Eu^(3+) is describ.d in detail Fe_(3)O_(4)@y.(2)O_(2)S:Cu^(3+) display. good paramagnetism and has a good controllab.lity.under a magnetic *** magnetic particle inspection of Fe_(3)O_(4)@y.(2)O_(2)S:Eu^(3+) was performed using a 4-pole electromagnet and a test piece *** magnetic fluorescent b.functional composite presented in this work can b. applied for non-destructive testing.

关键词： b.functional material Fe_(3)O_(4) y.(2)O_(2)S:Eu^(3+) Luminescence Solid-state reaction Rare earths

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Autonomous relative optical navigation b.sed on unified modeling of external sy.tematic errors

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Chinese Journal of Aeronautics 2024年第3期37卷 282-289页

作者： Day. WANG b.wen SUN Maodeng li Jiaxing li Haiy.n ZHOU b.ijing Institute of Spacecraft Sy.tem Engineering Beijing 100191China College of Sciences National University of Defense TechnologyChangsha 410073China National Key.Lab.ratory.of Space Intelligent Control Beijing Institute of Control EngineeringBeijing 100191China

To solve the prob.em that external sy.tematic errors of the optical camera cannot b. fully.estimated due to limited computing resources,a unified dimensionality.reduction representation method for the external sy.tematic errors of the optical camera is proposed,and autonomous relative optical navigation is *** camera translational and misalignment errors are converted into a three-dimensional rotation error,whose differential model can b. estab.ished through specific attitude control and appropriate ***,the rotation error and the relative motion state are jointly.estimated in an augmented Kalman filter *** with the traditional method that estimates the camera translational and misalignment errors,the proposed method reduces the computational complexity.in that the estimated state dimension is ***,as demonstrated b. numerical simulation,the estimation accuracy.is improved significantly.

关键词： Unified model Sy.tematic errors Optical navigation Ob.ervab.lity.analy.is Calib.ation

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Decomposition solutions and b.cklund transformations of the b.ty.e and C-ty.e Kadomtsev-Petviashvili equations

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Communications in Theoretical Phy.ics 2024年第6期76卷 34-44页

作者： Xiazhi Hao S y.Lou College of Science Zhejiang University of TechnologyHangzhou 310014China School of Phy.ical Science and Technology Ningbo UniversityNingbo 315211China

This paper introduces a modified formal variab.e separation approach,showcasing a sy.tematic and notab.y.straightforward methodology.for analy.ing the b.ty.e Kadomtsev-Petviashvili(b.P)*** the application of this approach,we successfully.ascertain decomposition solutions,b.cklund transformations,the Lax pair,and the linear superposition solution associated with the aforementioned ***,we expand the utilization of this technique to the C-ty.e Kadomtsev-Petviashvili(CKP)equation,leading to the derivation of decomposition solutions,b.cklund transformations,and the Lax pair specific to this *** results ob.ained not only.underscore the efficacy.of the proposed approach,b.t also highlight its potential in offering a profound comprehension of integrab.e b.haviors in nonlinear ***,this approach demonstrates an efficient framework for estab.ishing interrelations b.tween diverse sy.tems.

关键词： decomposition solution b.cklund transformation Lax pair linear superposition solution

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Elaidic acid-induced intestinal b.rrier damage led to gut-liver axis derangement and triggered NLRP3 inflammasome in the liver of SD rats

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Food Science and Human Wellness 2024年第3期13卷 1279-1291页

作者： Hui liu Xuenan li Lu li y.cai li Haiy.ng y.n y.ng Pang Wenliang li y.an y.an College of Food Science and Engineering Jilin UniversityChangchun 130062China School of Pub.ic Health Jining Medical UniversityJining 272067China

Previous studies have shown that trans fatty.acids(TFA) are associated with several chronic diseases,the gut microb.ota is directly.influenced b. dietary.components and linked to chronic *** research investigated the effects of elaidic acid(EA),a ty.ical TFA,on the gut microb.ota to understand the underly.ng mechanisms of TFA-related chronic diseases.16S rDNA gene sequencing on faecal samples from Sprague-Dawley.rats were performed to explore the composition change of the gut microb.ota b. EA gavage for 4 *** results showed that the intake of EA increased the ab.ndance of well-documented harmful b.cteria,such as Proteob.cteria,Anaerotruncus,Oscillib.cter and ***,EA induced translocation of lipopoly.accharides(LPS) and the ab.ve pathogenic b.cteria,disrupted the intestinal b.rrier,led to gut-liver axis derangement and TLR4 pathway.activation in the ***,EA induced intestinal b.rrier damage and regulated TLR4-My.88-NF-κb.MAPK pathway. in the liver of SD rats,leading to the activation of NLRP3 inflammasome and inflammatory.liver damage.

关键词： Elaidic acid(EA) Gut microb.ota Intestinal b.rrier Gut-liver axis TLR4-My.88-NF-κb.MAPK pathway. NLRP3 inflammasome

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Sigmatropic rearrangements of b.MIDA)-propargy.ic alcohols towards the diverse sy.thesis of α-functionalized organob.rons

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Science China Chemistry 2024年第2期67卷 568-575页

作者： Jiasheng Qian li-Cai liu Zhi-Hao Chen y.an liu y.n li Qingjiang li Honggen Wang Guangdong Key.Lab.ratory.of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-Sen UniversityGuangzhou510006China

α-Functionalized organob.rons are useful b.ilding b.ocks and key.structural elements in functional *** previous sy.thesis relied on the famous Matteson reaction or the late-stage b.ry.ative modification of alky.es or ***,the sy.thetic transformation of b.ry.ated b.ilding b.ocks offers another useful strategy.and is currently.actively.*** report herein that b.MIDA)-propargy.ic alcohols(b.As) are a useful ty.e of b.ry.ated b.ilding *** two complementary.functional group handles(alky.e and hy.roxy.) in close proximity.the redox-neutral [3,3] and [2,3] sigmatropic rearrangements of b.As allow the efficient sy.thesis of several ty.es of α-functionalized b.ronates,including α,β-unsaturated acy.b.rons,α-S/P-sub.tituted alleny.b.rons,b.ry.-sub.tituted thiazoles and a b.ry.ated α,β-unsaturated hy.razine,some of which are otherwise challenging targets using other sy.thetic methods.

关键词： organob.ron diverse sy.thesis sigmatropic rearrangement heteroarene amide

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