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Genotypic diversity of a dominant c_(4) grass across a long-term fire frequency gradient

Journal of Plant Ecology 2013年第6期6卷 448-458页

作者： cynthia c.chang Melinda D.Smith Department of Ecology and Evolutionary Biology Yale UniversityNew HavenCT 06511USA Department of Biology University of WashingtonSeattleWA 98195USA Department of Biology Colorado State UniversityFort CollinsCO 80523USA

Aims and Methods Diversity-disturbance research has focused on community diversity,but disturbance frequency could impact diversity within species as well,with important consequences for community diversity and ecosystem *** examined patterns of genetic diversity of a dominant grass species,Andropogon gerardii,in native North American tallgrass prairie sites located in eastern Kansas that have been subjected to a gradient of fire frequency treatments(burned every 1,2,4 or 20 years)since the *** addition,we were able to assess the relationships between genetic diversity of ***,species diversity and productivity across this range of fire *** Findings We found no significant relationships between genetic diversity of *** at the local scale(1 m^(2) plot level)and disturbance frequency(burned 2 to 32 times over a 38-year period).However,at the site level(*** all plots sampled within a site,~100 m^(2))there were differences in genotype richness and composition,as well as genomic dissimilarity among individuals of *** richness was greatest for the site burned at an intermediate(4-year)frequency and lowest for the infrequently(20-year)burned *** addition,genotypes found in the frequently burned sites were more similar from each other than expected by random chance than those found in the infrequently burned *** composition of *** was not significantly different between the frequently burned sites(annual vs.2 year)but did differ between frequently burned and infrequently burned sites(1 and 2 year vs.4 and 20 year,etc.).Together,these results suggest site-level ecological sorting of genotypes in intact prairie across a broad gradient of disturbance frequencies,likely driven by alterations in environmental *** fire promotes the abundance of dominant grass species,reduces plant community diversity and impacts ecosystem processes such as *** study suggests that

关键词： Andropogon gerardii disturbance frequency genetic relatedness genetic-species diversity relationship genotype richness intermediate disturbance hypothesis productivity tallgrass prairie

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Progress on the antiferromagnetic topological insulator MnBi2Te4

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National Science Review 2024年第2期11卷 33-49页

作者： Shuai Li Tianyu Liu chang Liu Yayu Wang Hai-Zhou Lu X.c.Xie Department of Physics Harbin Institute of Technology Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology(SUSTech) Quantum Science center of Guangdong-Hong Kong-Macao Greater Bay Area(Guangdong) Shenzhen Key Laboratory of Quantum Science and Engineering International Quantum Academy Beijing Academy of Quantum Information Sciences Beijing Key Laboratory of Optoelectronic Functional Materials&Micro-Nano Devices Department of Physics Renmin University of China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua University Frontier Science center for Quantum Information Hefei National Laboratory International center for Quantum Materials School of Physics Peking University Institute for Nanoelectronic Devices and Quantum computing Fudan University

Topological materials, which feature robust surface and/or edge states, have now been a research focus in condensed maTher physics. They represent a new class of materials exhibiting nontrivial topological phases,and provide a platform for exploring exotic transport phenomena, such as the quantum anomalous Hall effect and the quantum spin Hall effect. Recently, magnetic topological materials have attracted considerable interests due to the possibility to study the interplay between topological and magnetic *** particular, the quantum anomalous Hall and axion insulator phases can be realized in topological insulators with magnetic order. MnBi2Te4, as the first intrinsic antiferromagnetic topological insulator discovered, allows the examination of existing theoretical predictions; it has been extensively studied, and many new discoveries have been made. Here we review the progress made on MnBi2Te4from both experimental and theoretical aspects. The bulk crystal and magnetic structures are surveyed first, followed by a review of theoretical calculations and experimental probes on the band structure and surface states, and a discussion of various exotic phases that can be realized in MnBi2Te4. The properties of MnBi2Te4thin films and the corresponding transport studies are then reviewed, with an emphasis on the edge state transport. Possible future research directions in this field are also discussed.

关键词： MnBi2Te4 magnetic topological insulator antiferromagnetic quantum anomalous Hall effect axion insulator

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Effect of heat treatment on microstructure and mechanical properties of selective laser-melted PH13-8Mo stainless steel

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Journal of Iron and Steel Research(International) 2024年第4期31卷 945-955页

作者： Yuan Zhang Xiang Liu chang-jun Wang chang Liu School of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina central Iron&Steel Research Institute co. Ltd.Beijing 100081China

PH13-8Mo stainless steel powder with high sphericity and well fluidity was prepared by the plasma rotating electrode *** formed parts with ultra-high purity were manufactured by selective laser *** tensile and impact mechanical properties of the printed parts under three heat treatment regimes were compared to those without heat *** microstructure,grain orientation and phase composition were characterized by electron-backscatter diffraction,X-ray diffraction and transmission electron *** characterization results reveal that the addition of heat treatment makes the grains enlarge,and after different heat treatments,the average grain size from 1.51μm in the printed state increases to 2.78,3.09 and 2.06μm,*** formed parts are mainly composed of martensite and retained ***,the NiAl and M23c precipitates form,which are the major strengthening phases of PH13-8Mo stainless *** optimal heat treatment process is 925℃×1 h water cooling(Wc)+0℃×2 h air cooling(Ac)+540℃×4 h *** this heat treatment process,PH13-8Mo formed parts have the optimal comprehensive mechanical properties:the tensile strength,yield strength and impact energy KU2 are 1492 MPa,1432 MPa and 63 J,*** strengthening and toughening via heat treatment are mainly attributed to dislocation strengthening,the formation of NiAl and M23co precipitates and the change of volume fraction of the retained austenite.

关键词： High-strength stainless steel-Selective laser melting-Heat treatment Microstructure Mechanical property

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SMXL5 attenuates strigolactone signaling in Arabidopsis thaliana by inhibiting SMXL7 degradation

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Molecular Plant 2024年第4期17卷 631-647页

作者： Qingtian Li Haiyang Yu Wenwen chang Sunhyun chang Michael Guzman Lionel Faure Eva-Sophie Wallner Heqin Yan Thomas Greb Lei Wang Ruifeng Yao David c.Nelson Department of Botany and Plant Sciences University of CaliforniaRiversideRiversideCA 2521USA Yazhouwan National Laboratory Sanya 572025China Hainan Seed Industry Laboratory Sanya 57205China State Key Laboratory of chemo/Biosensing and chemometrics Hunan Provincial Key Laboratory of Plant Functional Genomics and Developmental RegulationCollege of BiologyHunan UniversityChangsha 410082China Key Laboratory of Seed Innovation Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuangHebei 050021China University of chinese Academy of Sciences Beijing 10004China School of the Sciences Biology DivisionTexas Woman’s UniversityDentonTX 76204USA centre for Organismal Studies(cOS) Heidelberg University6120 HeidelbergGermany

Hormone-activated proteolysis is a recurring theme of plant hormone signaling *** strigolactone signaling,the enzyme receptor DWARF14(D14)and an F-box protein,MORE AXILLARY GROWTH2(MAX2),mark SUPPRESSOR OF MAX21-LIKE(SMXL)family proteins SMXL6,SMXL7,and SMXL8 for rapid *** of these transcriptional corepressors initiates downstream growth *** homologous proteins SMXL3,SMXL4,and SMXL5,however,are resistant to MAX2-mediated *** discovered that the smxl4 smxl5 mutant has enhanced responses to ***5 attenuates strigolactone signaling by interfering with AtD14-SMXL7 ***5 interacts with AtD14 and SMXL7,providing two possible ways to inhibit SMXL7 ***5 function is partially dependent on an ethylene-responsive-element binding-factor-associated amphiphilic repression(EAR)motif,which typically mediates interactions with the TOPLESS family of transcriptional ***,we found that loss of the EAR motif reduces SMXL5-SMXL7 interactions and the attenuation of strigolactone signaling by *** hypothesize that integration of SMXL5 into heteromeric SMXL complexes reduces the susceptibility of SMXL6/7/8 proteins to strigolactone-activated degradation and that the EAR motif promotes the formation or stability of these *** mechanism may provide a way to spatially or temporally fine-tune strigolactone signaling through the regulation of SMXL5 expression or translation.

关键词： Arabidopsis typically inhibiting

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Designing a Secure and Scalable Data Sharing Mechanism Using Decentralized Identifiers(DID)

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computer Modeling in Engineering & Sciences 2024年第10期141卷 809-822页

作者： Iuon-chang Lin I-Ling Yeh ching-chun chang Jui-chuan Liu chin-chen chang Department of Management Information Systems National Chung Hsing UniversityTaichung402Taiwan Information and communication Security Research center Feng Chia UniversityTaichung407Taiwan Department of Information Engineering and computer Science Feng Chia UniversityTaichung407Taiwan

centralized storage and identity identification methods pose many risks,including hacker attacks,data misuse,and single points of ***,existing centralized identity management methods face interoperability issues and rely on a single identity provider,leaving users without control over their ***,this paper proposes a mechanism for identity identification and data sharing based on decentralized *** scheme utilizes blockchain technology to store the identifiers and data hashed on the chain to ensure permanent identity recognition and data *** is stored on InterPlanetary File System(IPFS)to avoid the risk of single points of failure and to enhance data persistence and *** the same time,compliance with World Wide Web consortium(W3c)standards for decentralized identifiers and verifiable credentials increases the mechanism’s scalability and interoperability.

关键词： Self-sovereign identity decentralized identifier blockchain

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AHermitian c^(2) Differential Reproducing Kernel Interpolation Meshless Method for the 3D Microstructure-Dependent Static Flexural Analysis of Simply Supported and Functionally Graded Microplates

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computer Modeling in Engineering & Sciences 2024年第10期141卷 917-949页

作者： chih-Ping Wu Ruei-Syuan chang Department of civil Engineering National Cheng Kung UniversityTainan70101Taiwan

This work develops a Hermitian c^(2) differential reproducing kernel interpolation meshless(DRKIM)method within the consistent couple stress theory(ccST)framework to study the three-dimensional(3D)microstructuredependent static flexural behavior of a functionally graded(FG)microplate subjected to mechanical loads and placed under full simple *** the formulation,we select the transverse stress and displacement components and their first-and second-order derivatives as primary ***,we set up the differential reproducing conditions(DRcs)to obtain the shape functions of the Hermitian c^(2) differential reproducing kernel(DRK)interpolant’s derivatives without using direct *** interpolant’s shape function is combined with a primitive function that possesses Kronecker delta properties and an enrichment function that constituents *** a result,the primary variables and their first-and second-order derivatives satisfy the nodal interpolation ***,incorporating ourHermitianc^(2)DRKinterpolant intothe strong formof the3DccST,we develop a DRKIM method to analyze the FG microplate’s 3D microstructure-dependent static flexural *** Hermitian c^(2) DRKIM method is confirmed to be accurate and fast in its convergence rate by comparing the solutions it produces with the relevant 3D solutions available in the ***,the impact of essential factors on the transverse stresses,in-plane stresses,displacements,and couple stresses that are induced in the loaded microplate is *** factors include the length-to-thickness ratio,the material length-scale parameter,and the inhomogeneity index,which appear to be significant.

关键词： consistent/modified couple stress theory differential reproducing kernel methods microplates point collocation methods static flexural 3D microstructure-dependent analysis

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Generalized polynomial chaos expansion by reanalysis using static condensation based on substructuring

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 819-836页

作者： D.LEE S.chang J.LEE Department of Automotive Engineering Hanyang UniversitySeoul 04763Republic of Korea School of Mechanical Engineering Chungnam National UniversityDaejeon 34134Republic of Korea Department of Mechanical Robotics and Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea

This paper presents a new computational method for forward uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary and dependent random *** method consists of a generalized polynomial chaos expansion(GPcE)for statistical moment and reliability analyses associated with the stochastic output and a static reanalysis method to generate the input-output data *** the reanalysis,we employ substructuring for a structure to isolate its local regions that vary due to random *** allows for avoiding repeated computations of invariant substructures while generating the input-output data *** substructuring with static condensation further improves the computational efficiency of the reanalysis without losing ***,the GPcE with the static reanalysis method can achieve significant computational saving,thus mitigating the curse of dimensionality to some degree for UQ under high-dimensional *** numerical results obtained from a simple structure indicate that the proposed method for UQ produces accurate solutions more efficiently than the GPcE using full finite element analyses(FEAs).We also demonstrate the efficiency and scalability of the proposed method by executing UQ for a large-scale wing-box structure under ten-dimensional(all-dependent)random inputs.

关键词： forward uncertainty quantification(UQ) generalized polynomial chaos expansion(GPcE) static reanalysis method static condensation substructuring

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Laser Powder Bed Fusion of Beta-Type Titanium Alloys for Biomedical Application:A Review

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 17-28页

作者： Xuan Luo chao Yang Dongdong Li Lai-chang Zhang State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China National Engineering Research center of Near-Net-Shape Forming for Metallic Materials Guangdong Provincial Key Laboratory for Processing and Forming of Advanced Metallic MaterialsSouth China University of TechnologyGuangzhou510640China centre for Advanced Materials and Manufacturing School of EngineeringEdith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

Additive manufacturing ofβ-type titanium alloy is expected to replace Ti-6Al-4V alloy in the field of orthopedic implantation because of their low elastic modulus,excellent corrosion resistance,and *** briefly introducing the laser powder bed fusion(LPBF)process and physical phenomena,this paper reviews the recent progresses in LPBF-edβ-type Ti *** strategies to strengthening and tougheningβ-type Ti alloys are critically *** is followed by the processing routes employed to achieve to low modulus for orthopedic applications,especially a new methodology for tailoring crystallographic orientation called multi-track coupled directional *** effect of processing and compositions on performance metrics ofβ-type Ti alloys included corrosion behavior,and biocompatibility is *** the end,challenges in additive manufacturing ofβ-type Ti alloys in future are highlighted,with the aim to ensue clinical application of LPBF-edβ-type Ti alloys.

关键词： β-type Ti alloys Laser powder bed fusion Mechanical properties Elastic modulus Biocompatibility

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Palladium-catalyzed multi components oxy-aminofluorination and aminofluorination of gem-difluoroalkenes

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chinese chemical Letters 2024年第2期35卷 420-425页

作者： Fen Wu Xin Li Junbiao chang Dachang Bai State Key Laboratory of Antiviral Drugs NMPA Key Laboratory for Research and Evaluation of Innovative DrugKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringPingyuan LaboratoryHenan Normal UniversityXinxiang 453007China State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Organofluorine compounds are widely used in the realm of drug discovery and material ***,we developed palladium catalyzed intermolecular aminofluorination and oxy-aminofluorination of gem‑difluoroalkenes with N-fluorobenzenesulfonimide(NFSI),in which NFSI was used as the nitrogen source and *** reaction provides an efficient and straightforward synthesis route of a series ofα-trifluoromethyl benzylic ***,three/four components oxy-aminofluorination processes were realized to giveα-trifluoromethyl benzylic ether with a terminal amino group,which proceed through c(sp^(3))-O bond cleavage of easily available ether and simultaneous introduced a fluorine,an amino and an oxy substituent in one pot with excellent *** divergent reactivity not only included the incorporation of one ether molecular,but also much more challenged two ether insertion with excellent selectivity through succession c(sp^(3))-O bonds *** protocol allows for concise synthesis of high value amines with fluoroalkyl-substituents and selectively transformation of easily available ethers by high-valent palladium catalysis.

关键词： Palladium Multi components Aminofluorination Oxy-aminofluorination c(sp^(3))-O bond cleavage

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Low carbon alcohol fuel electrolysis of hydrogen generation catalyzed by a novel and effective Pt–coTe/c bifunctional catalyst system

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Green Energy & Environment 2024年第4期9卷 758-770页

作者： Yang Zhou Lice Yu Jinfa chang Ligang Feng Jiujun Zhang School of chemistry and chemical Engineering Yangzhou UniversityYangzhou225002JiangsuChina NanoScience Technology center University of Central FloridaOrlandoFL32826USA college of Sciences&Institute for Sustainable Energy Shanghai UniversityShanghai200444China

Low carbon alcohol fuels electrolysis under ambient conditions is promising for green hydrogen generation instead of the traditional alcohol fuels steam reforming technique,and highly efficient bifunctional catalysts for membrane electrode fabrication are required to drive the electrolysis ***,the efficient catalytic promotion effect of a novel catalyst promoter,coTe,on Pt is demonstrated for low carbon alcohol fuels of methanol and ethanol electrolysis for hydrogen *** and density functional theory calculation results indicate that the optimized electronic structure of Pt–coTe/c resulting from the synergetic effect between Pt and coTe further regulates the adsorption energies of cO and H*that enhances the catalytic ability for methanol and ethanol ***,the good water activation ability of coTe and the strong electronic effect of Pt and coTe increased the tolerance ability to the poisoning species as demonstrated by the cO-stripping *** high catalytic kinetics and stability,as well as the promotion effect,were also carefully ***,71.9%and 75.5%of the initial peak current density was maintained after 1000 cV cycles in acid electrolyte for methanol and ethanol oxidation;and a low overpotential of 30 and 35 mV was required to drive the hydrogen evolution reaction in methanol and ethanol solution at the current density of 10 mA cm^(-2).In the two-electrode system for alcohol fuels electrolysis,using the optimal Pt–coTe/c catalyst as bi-functional catalysts,the cell potential of 0.66 V(0.67 V)was required to achieve 10 mA cm^(-2) for methanol(ethanol)electrolysis,much smaller than that of water electrolysis(1.76 V).The current study offers a novel platform for hydrogen generation via low carbon alcohol fuel electrolysis,and the result is helpful to the catalysis mechanism understanding of Pt assisted by the novel promoter.

关键词： Methanol electrolysis Ethanol electrolysis cobalt telluride Pt-based electrocatalyst Hydrogen evolution reaction

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