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国际医学放射学杂志 2023年第6期 744-745页

作者： z.y.liu B.Hou H.you L.Lu L.Duan M.L.Li 王倩

摘要目的对比二维快速自旋回波（2D FSE）序列的常规增强MRI(cMRI)和动态增强MRI(dMRI)，评估高分辨三维快速自旋回波（3D FSE）序列的MRI(hrMRI)对垂体微腺瘤

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Screening and identification of salt tolerance soybean varieties and germplasms

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Oil Crop Science 2024年第3期9卷 204-210页

作者： Chen L. Peng L. Ouyang W. yao H. ye y. Shan z. Cao D. Chen S. yang z. Huang y. Han B. Sha A. zhou X. Chen H. Key Laboratory of Biology and Genetic Improvement of Oil Crops Ministry of Agriculture and Rural Affairs Oil Crops Research Institute of Chinese Academy of Agricultural Sciences Wuhan 430062 China College of Agriculture Yangtze University Jingzhou 434000 China

Soil salinization is a globally prevalent abiotic environmental stress. The imbalance of ions caused by high concentrations of sodium chloride results in a 40% reduction in soybean yield. Soybean, as an important crop for soil quality improvement, necessitates the identification of salt-tolerant varieties and germplasms to effectively utilize and enhance saline-alkali land. In this study, we assessed the salt tolerance of 435 soybean varieties and germplasms during the seedling stage. Among them, Qihuang34, you2104, Hongzhudou, Pamanheidou, and Osage exhibited grade 1 salt tolerance rates surpassing other tested materials. Furthermore, Hongzhudou and Qihuang34 demonstrated higher salt tolerance during germination and emergence stages based on their elevated rates of emergence, salt tolerance index, chlorophyll content, and shoot fresh weights. Overall findings provide valuable resources for molecular breeding efforts aimed at developing salt-tolerant soybean varieties suitable for cultivation in saline-alkali soils. © 2024 the Oil Crop Research Institute, Chinese Academy of Agriculture Sciences

关键词： Germination and emergence stage Germplasms Salt tolerance Seedling stage Soybean Varieties

Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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Matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： y.X.Wang X.L.zhu S.M.Weng P.Li X.F.Li H.Ai H.R.Pan z.M.Sheng Key Laboratory for Laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of Laser Fusion of China Academy of Engineering Physics MianyangSichuan 621900China State key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(THz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or THz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or THz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and THz spectral ranges.

关键词： laser ultrashort photon

A REFINEMENT OF THE SCHWARz-PICK ESTIMATES AND THE CARATHéODORy METRIC IN SEVERAL COMPLEX VARIABLES

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Acta Mathematica Scientia 2024年第4期44卷 1337-1346页

作者： Xiaosong liu Taishun liu School of Mathematics and Statistics Lingnan Normal UniversityZhanjiang 524048China Department of Mathematics Huzhou UniversityHuzhou 313000China

In this article,we first establish an asymptotically sharp result on the higher order Fréchet derivatives for bounded holomorphic mappings f(x)=f(0)+∞∑s=1Dskf(0)(x^(sk))/(sk)!:B_(X)→B_(y),where B_X is the unit ball of *** next give a sharp result on the first order Fréchet derivative for bounded holomorphic mappings F(X)=F(0+)∞∑s=KD^(s)f(0)(x^(8)/s!):B_(X)→B_(y),where B_(X)is the unit ball of *** results that we derive include some results in several complex variables,and extend the classical result in one complex variable to several complex variables.

关键词： refined Schwarz-Pick estimate bounded holomorphic mapping Carathéodory metric first order Fréchet derivative higher order Fréchet derivatives

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A compact bimorph rotary piezoelectric actuator with customized small power supply

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Science China(Technological Sciences) 2024年第4期67卷 1185-1195页

作者： DENG Jie liu DaQing WANG Weiyi liu yingXiang School of Mechatronics and Engineering Harbin Institute of TechnologyHarbin 150001China

Inertial piezoelectric actuators are widely applied in precision devices with simple structure and accurate ***,existing inertial piezoelectric actuators still face the challenges of rollback motion and bulky power *** this work,an alternate excitation strategy and a customized small power supply for a bimorph rotary piezoelectric actuator(BRPA)are proposed to solve the *** BRPA prototype is designed with a bipedal symmetrical structure,measuring 35 mm in height and 32 mm in diameter,which has a maximum rotation velocity of 0.247 rad/s and a resolution of 0.66μ*** to the bipedal symmetrical structure,the friction directions between the driving feet and the rotor can be coordinated to suppress the *** rollback ratio is almost zero when the phase difference of the exciting signal is set as 180°.The customized power supply is designed and manufactured,whose size is 58 mm×56 mm×46 *** can output signals for the single step mode and the continuous mode,and they are adopted to excite BRPA to achieve a small stroke with one single step and a large stroke with continuous step,***,an experimental system for optical fiber alignment is developed based on the BRPA and the customized small power supply,the experiment has verified the practicability of this work in the precision fields,especially in the miniaturized precision systems.

关键词： inertial piezoelectric actuator customized small power supply single step mode continuous mode rollback suppression miniaturized precision system

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Localization−delocalization transitions in non-Hermitian Aharonov−Bohm cages

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Frontiers of physics 2024年第3期19卷 39-50页

作者： Xiang Li Jin liu Tao liu School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

A unique feature of non-Hermitian systems is the extreme sensitivity of the eigenspectrum to boundary conditions with the emergence of the non-Hermitian skin effect (NHSE). A NHSE originates from the point-gap topology of complex eigenspectrum, where an extensive number of eigenstates are anomalously localized at the boundary driven by nonreciprocal dissipation. Two different approaches to create localization are disorder and flat-band spectrum, and their interplay can lead to the anomalous inverse Anderson localization, where the Bernoulli anti-symmetric disorder induces mobility in a full-flat band system in the presence of Aharonov−Bohm (AB) Cage. In this work, we study the localization−delocalization transitions due to the interplay of the point-gap topology, flat band and correlated disorder in the one-dimensional rhombic lattice, where both its Hermitian and non-Hermitian structures show AB cage in the presence of magnetic flux. Although it remains the coexistence of localization and delocalization for the Hermitian rhombic lattice in the presence of the random anti-symmetric disorder, it surprisingly becomes complete delocalization, accompanied by the emergence of NHSE. To further study the effects from the Bernoulli anti-symmetric disorder, we found the similar NHSE due to the interplay of the point-gap topology, correlated disorder and flat bands. Our anomalous localization−delocalization property can be experimentally tested in the classical physical platform, such as electrical circuit.

关键词： non-Hermitian skin effects disorder flat band localization−delocalization transition

Application of dual color fluorescence in situ hybridiza tion (D-FISH) to the diagnosis of a 49, XXXXy chromo somal abnormality

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Asian Journal of Andrology 2002年第4期4卷 302-302页

作者： y.z. liu, X. zeng Department of Biology, Wenzhou Medical College, Wenzhou 325027, China

To study the technique of D-FISH and its application in the diagnosis of a 49, XXXXy chromosomal abnormality. Methods: Biotin-labeled alpha satellite X chromosome DNA (pBamX7) probe and digoxi-genin-labeled y chromosome long arm terminal repetitive sequence (py3.4) probe in situ hybridized with pre-treated slides of peripheral blood chromosome and interphase nucleus. After washing, the slides were treated with avidin-FITC, rhodamine-FITC and anti-avidin, amplified with an additional layer and counter-stained with DAPI in an antifade solution. The hy bridization signals and chromosomal or interphase nucleus settings were observed respectively with WIB, WIG and WU filters under fluorescent microscope (Olympus AX-70) and the number of metaphase chromosome and interphase nucleus in the peripheral blood was counted. Results: The biotin-labeled pBamX7 probe showed 4 green hybridization signal and the digoxigenin-labeled py3.4 probe showed 1 red hybridization signal. The chromosome or cytoplasm counter-stained with DAPI showed blue. The positive rate of X chromosome hybridization signal for the 350 metaphase chromosomes and interphase nucleus was 91.43 % and 92. 57 %, respectively, while that of the y chromosome hybridization signal was 99.5 % and 99.8 %, respectively. Conclusion: D-FISH is a valuable technique in diagnosing 49, XXXXy chromosomal abnormality and other sex chromosomal abnormalities. [Reprod Contracep (in Chinese) 2002; 22: 287]

关键词： dual-color fluorescence in situ hybridization sex chromosomal abnormalities DNA special probe

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Linking 24-h Movement Behavior Guidelines to Cognitive Difficulties, Internalizing and Externalizing Problems in Preterm youth

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International Journal of Mental Health Promotion 2024年第8期26卷 651-662页

作者： Cheng z. Aikeremu A. Gao y. zhang z. Delli Paoli A.G. Cunha P.M. Taylor A. Herold F. zou L. Body-Brain-Mind Laboratory School of Psychology Shenzhen University Shenzhen 518060 China Department of Kinesiology and Health Rutgers University New Brunswick 08901 NJ United States Metropolitan University Center of Maringá Maringá 87020 Brazil School of Health and Rehabilitation Sciences AECC University College Bournemouth BH5 2DF United Kingdom Research Group Degenerative and Chronic Diseases Movement Faculty of Health Sciences Brandenburg University of Potsdam Potsdam 14476 Germany

Background: Given the heightened risk of developmental challenges associated with preterm birth, it is crucial to explore interventions that may ameliorate potential adverse outcomes. This study aimed to examine whether meeting the 24-h movement behavior (24-HMB) guidelines, which include recommendations on physical activity (PA), screen time (ST), and sleep (SL), is related to indicators of cognitive difficulties, internalizing problems (e.g., depression and anxiety), and externalizing problems (e.g., difficulties in making friends and arguing) in a sample of preterm youth (children and adolescents born preterm). Methods: In this cross-sectional study, data from 3410 preterm youth (aged 6 to 17 years) were included for data analyses. Multivariable logistic regression was used to investigate associations between meeting the 24-HMB guidelines and the above-mentioned health outcomes, while controlling for sociodemographic and health-related factors. Results: The prevalence of meeting 24-HMB guidelines varied across independent and integrated components of the 24-HMB guidelines. Meeting the ST guideline alone (p zing and externalizing problems (p y, meeting the SL guideline alone and integrated guidelines (i.e., SL + ST) were associated with lower odds of depression and anxiety (p y, meeting independent, and integrated (PA and/or ST) guidelines were associated with less pronounced difficulties in making friends and arguing (p zing and externalizing problems in preterm youth. Conclusion: Results suggest that advocating for the implementation of the 24-HMB guidelines may reduce cognitive challenges and behavioral issues, which is of high relevance for improving pub

关键词： Cognitive difficulties externalizing problems internalizing problems physical activity preterm youth

Identification of the optimal doping position of hetero-atoms in chalcogen-doped Fe-N-C catalysts for oxygen reduction reaction

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Particuology 2024年第6期89卷 99-108页

作者： Weihao liu Huanhuan He Qingtao liu Xin Wan Jianglan Shui School of Materials Science and Engineering Beihang UniversityBeijing100191China School of Space and Environment Beihang UniversityBeijing102206China Tianmushan Laboratory Hangzhou310023China

The excellent oxygen reduction reaction(ORR)activity of Fe–N–C catalysts in acidic media makes them potential for low-cost proton exchange membrane fuel *** recent years,it has been shown that heteroatoms(B,O,S,P,Cl,F,etc.)can be used as electron-withdrawing groups to modulate the planar structure and electron distribution of the Fe–Nx active sites to achieve simultaneous improvement of catalytic activity and ***,the optimal location of the heteroatoms remains ***,taking chalcogen heteroatoms(S and Se)as an example,we control the doping positions and investigate their effect on the ORR performance of the Fe–N–C *** first coordination shell of the iron single atom is identified as the optimal doping *** optimized catalysts Fe–N_(3)Se_(1)/NC and Fe–N_(3)Se_(1)/NC demonstrate improved activity and stability in both half cells and fuel *** work provides insights into the enhancement mechanism of heteroatom doping in single-atom catalysts.

关键词： Oxygen reduction reaction Fe-N-C catalysts Hetero-atom doping Doping position Enhancement mechanism

Stable hydrogen-bonded organic frameworks and their photo-and electro-responses

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Nano Research 2024年第8期17卷 7675-7699页

作者： ying Hou Xin-Song Huang Sheng-Hao Gong Chen liu yangyang liu Tian-Fu liu State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China Department of Chemistry and Biochemistry California State UniversityLos AngelesCalifornia 90032USA College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China

Hydrogen-bonded organic frameworks(HOFs)are a recent class of porous materials that have garnered considerable research interest owing to their distinctive *** can be constructed through judicious selection of H-bonding motifs,which are further enforced by other weak intermolecular interactions such asπ–πstacking,van der Waals forces,and framework *** advantage of these interactions,we can expand the functional field of HOFs by introducing active ***,researchers have made substantial advancements in using HOFs for chemical sensing,catalysis,proton conduction,biological applications,and *** low bonding energy of H-bonds allows for precise control over the concentration of ligands in solvents,forming diverse HOF *** varied structures offer significant advantages for producing HOFs with photo-responsive and electro-responsive ***,the presence of H-bonds in HOFs results in their inherent lower stability compared to metal-organic frameworks(MOFs)and covalent-organic frameworks(COFs)formed via coordination and covalent bonds,*** a result,the pursuit of stable and innovative HOF materials with novel functional sites remains an ongoing *** review provides an overview of recent research progress in the development of new strategies for stable HOF synthesis and applications of HOFs with stimuli-responsive *** first classified all synthetic methods reported to date and discussed the stable HOFs synthesized,as well as their unique properties and *** addition,we summarized the applications of HOFs utilizing their synergistic responses to external stimuli,including photo,electrical,pressure,and chemical *** systematically reviewed stable HOF synthesis and applications,which may lead to a deeper understanding of the structure–activity relationship for these materials and guide future HOF design.

关键词： stable hydrogen-bonded organic frameworks(HOFs) photo-response electro-response photoelectric synergistic response