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Research in Astronomy and Astrophysics 2024年第7期24卷 158-169页

作者： Yining Wang Rui Sun Tianyuan Deng Chenghui zhao Peixuan zhao Jiayi Yang Peng Jia Huigen Liu Jilin Zhou College of Electronic Information and Optical Engineering Taiyuan University of TechnologyTaiyuan 030024China School of Astronomy&Space Science Nanjing UniversityNanjing 210093China Peng Cheng Lab Shenzhen 518066China

The China Space Station Telescope(CSST)is a telescope with 2 m diameter,obtaining images with high quality through wide-field *** its first observation cycle,to capture time-domain observation data,the CSST is proposed to observe the Galactic halo across different *** data have significant potential for the study of properties of stars and ***,the density of stars in the Galactic center is high,and it is a well-known challenge to perform astrometry and photometry in such a dense star *** paper presents a deep learning-based framework designed to process dense star field images obtained by the CSST,which includes photometry,astrometry,and classifications of targets according to their light curve *** simulated CSST observation data,we demonstrate that this deep learning framework achieves photometry accuracy of 2%and astrometry accuracy of 0.03 pixel for stars with moderate brightness mag=24(i band),surpassing results obtained by traditional ***,the deep learning based light curve classification algorithm could pick up celestial targets whose magnitude variations are 1.7 times larger than magnitude variations brought by Poisson photon *** anticipate that our framework could be effectively used to process dense star field images obtained by the CSST.

关键词： techniques photometric-methods data analysis-astrometry

Operando NmR methods for studying electrocatalysis

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magnetic Resonance Letters 2024年第2期4卷 54-64页

作者： Zhiyu Zhu Ruipeng Luo Evan Wenbo zhao magnetic Resonance Research Center Institute for Molecules and MaterialsRadboud University6525 AJ Nijmegenthe Netherlands

The combination of electrochemical measurements with spectroscopic characterizations provides valuable insights into reaction *** magnetic resonance(NmR)spectroscopy,as a powerful technique due to its atomic specificity and versatility in studying gas,liquid,and solid,allows the study of electrolyte solution,catalyst and catalyst-adsorbate *** applied in operando,NmR can offer molecular-level insights into various electrochemical *** NmR has been applied extensively in battery research,but relatively underexplored for electrocatalysis in the past two *** this mini review,we first introduce the operando electrochemical NmR setups,categorized by different probe *** we review the applications of operando NmR for monitoring the electrolyte solution and the catalyst-adsorbate *** the high environmental impact of electrochemical conversion of CO_(2)into value-added products,we zoom in to the use of operando NmR in studying electrochemical CO_(2)***,we provide our perspective on further developing and applying operando NmR methods for understanding the complex reaction network of Cu-catalyzed electrochemical CO_(2)reduction.

关键词： Operando NmR In situ NmR EC-NmR Electrocatalysis Electrochemical CO_(2)reduction

Discrete Element modelling of Damage Evolution of Concrete Considering meso-Structure of ITZ

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Computer modeling in Engineering & Sciences 2024年第6期139卷 3495-3511页

作者： Weiliang Gao Shixu Jia Tingting zhao Zhiyong Wang Institute of Defense Engineering Academy of Military SciencesChinese People’s Liberation ArmyBeijing100850China College of mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan030024China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

The mechanical properties of interfacial transition zones(ITZs)have traditionally been simplified by reducing the stiffness of cement in previous simulation methods.A novel approach based on the discrete element method(DEm)has been developed for modeling *** new approach efficiently simulates the meso-structure of ITZs,accurately capturing their heterogeneous *** against established uniaxial compression experiments confirms the precision of *** proposedmodel canmodel the process of damage evolution containing cracks initiation,propagation and *** increasing loads,cracks within ITZs progressively accumulate,culminating in macroscopic fractures that traverse themortarmatrix,forming the complex,serpentine path of *** study reveals four distinct displacement patterns:tensile compliant,tensile opposite,mixed tensile-shear,and shear opposite patterns,each indicative of different stages in concrete’s damage *** widening angle of these patterns delineates the progression of cracks,with the tensile compliant pattern signaling the initial crack appearance and the shear opposite pattern indicating the concrete model’s ultimate failure.

关键词： Discrete element method damage evolution interfacial transition zone meso-structure model

Geometry characteristics and wide temperature behavior of silicon-based GaN surface acoustic wave resonators with ultrahigh quality factor

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Science China(Information Sciences) 2024年第2期67卷 267-278页

作者： Guofang YU Renrong LIANG Haiming zhao Lei XIAO Jie CUI Yue zhao Wenpu CUI Jing WANG Jun XU Jun FU Tianling REN School of Integrated Circuits Tsinghua University Beijing National Research Center for Information Science Technology Tsinghua University

Surface acoustic wave(SAW) resonators with an ultrahigh Q-factor are designed and fabricated on silicon-based gallium nitride(GaN/Si). The temperature-dependent performance is characterized over a wide range, from 10 to 500 K. Finite element analysis is employed to guide the design of the SAW resonator from indications of the Rayleigh mode and weak propagation direction dependence of SAW in the c-plane of GaN/Si. The SAW resonator with 100 pairs of interdigital transducers(IDT), 100 pairs of grating reflectors(GR) for each side, aperture size of 80 μm, metallization ratio of 0.5, and electrode width of 500 nm resonates at 1.9133 GHz accordingly with an ultrahigh Q-factor of 7622 at room temperature, which contributes the fr× Qr, up to 14.583×1012Hz. A resonator operating over 10 to 500 K indicates an approximately linear decreasing temperature dependence above 280 K while being approximately constant below 40 K. The fitting to resonator characteristics using the modified Butterworth Van Dyke(m BVD) model reveals a reduction in both the electrode and mechanical losses while worsening the dielectric loss with cooling down.

关键词： GaN/Si SAW resonator ultrahigh Q-factor temperature-dependent performance mBVD losses

Development of a single transcript CRISPR/Cas9 toolkit for efficient genome editing in autotetraploid alfalfa

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The Crop Journal 2024年第3期12卷 788-795页

作者： Haixia zhao Siyi zhao Yingping Cao Xiping Jiang Lijuan zhao Zhimeng Li mengqi Wang Ruijuan Yang Chuanen Zhou zhaoming Wang Feng Yuan Dongmei ma Hao Lin Wenwen Liu Chunxiang Fu CAS Key Laboratory of Biofuels Shandong Provincial Key Laboratory of Energy GeneticsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101ShandongChina Shandong Energy Institute Qingdao 266101ShandongChina Qingdao New Energy Shandong Laboratory Qingdao 266101ShandongChina University of Chinese Academy of Sciences Beijing 100049China The Key Laboratory of Plant Development and Environmental Adaptation Biology Ministry of EducationSchool of Life SciencesShandong UniversityQingdao 266101ShandongChina Key Laboratory of Forage Breeding and Seed Production of Inner mongolia Inner Mongolia M-Grass Ecology and Environment(Group)Co.Ltd.Hohhot 010016Inner MongoliaChina School of Ecology Environment Ningxia UniversityYinchuan 750021NingxiaChina Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China

Alfalfa(medicago sativa.L.)is a globally significant autotetraploid legume forage ***,despite its importance,establishing efficient gene editing systems for cultivated alfalfa remains a formidable *** this study,we pioneered the development of a highly effective ultrasonic-assisted leaf disc transformation system for Gongnong 1 alfalfa,a variety widely cultivated in Northeast ***,we created a single transcript CRISPR/Cas9(CRISPR_2.0)toolkit,incorporating multiplex gRNAs,designed for gene editing in Gongnong *** Cas9 and gRNA scaffolds were under the control of the Arabidopsis ubiquitin-10 promoter,a widely employed polymeraseⅡconstitutive promoter known for strong transgene expression in *** assess the toolkit’s efficiency,we targeted PALm1,a gene associated with a recognizable multifoliate *** the CRISPR_2.0 toolkit,we directed PALm1 editing at two sites in the wild-type Gongnong *** indicated a 35.1%occurrence of editing events all in target 2 alleles,while no mutations were detected at target 1 in the transgenic-positive *** explore more efficient sgRNAs,we developed a rapid,reliable screening system based on Agrobacterium rhizogenes-mediated hairy root transformation,incorporating the visible reporter *** screening system demonstrated that most purple visible hairy roots underwent gene ***,sgRNA3,with an 83.0%editing efficiency,was selected using the visible hairy root *** anticipated,tetra-allelic homozygous palm1 mutations exhibited a clear multifoliate *** palm1 lines demonstrated an average crude protein yield increase of 21.5%compared to trifoliolate *** findings highlight the modified CRISPR_2.0 system as a highly efficient and robust gene editing tool for autotetraploid alfalfa.

关键词： Alfalfa Gene editing CRISPR_2.0 toolkit Hairy root system Tetra-allelic homozygous mutants

A Survey of Knowledge Graph Construction Using machine Learning

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Computer modeling in Engineering & Sciences 2024年第4期139卷 225-257页

作者： Zhigang zhao Xiong Luo maojian Chen Ling ma School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Shunde Innovation School University of Science and Technology BeijingFoshan528399China Beijing Key Laboratory of Knowledge Engineering for materials Science Beijing100083China

Knowledge graph(KG)serves as a specialized semantic network that encapsulates intricate relationships among real-world entities within a structured *** framework facilitates a transformation in information retrieval,transitioning it from mere string matching to far more sophisticated entity *** this transformative process,the advancement of artificial intelligence and intelligent information services is ***,the role ofmachine learningmethod in the construction of KG is important,and these techniques have already achieved initial *** article embarks on a comprehensive journey through the last strides in the field of KG via machine *** a profound amalgamation of cutting-edge research in machine learning,this article undertakes a systematical exploration of KG construction methods in three distinct phases:entity learning,ontology learning,and knowledge ***,a meticulous dissection of machine learningdriven algorithms is conducted,spotlighting their contributions to critical facets such as entity extraction,relation extraction,entity linking,and link ***,this article also provides an analysis of the unresolved challenges and emerging trajectories that beckon within the expansive application of machine learning-fueled,large-scale KG construction.

关键词： Knowledge graph(KG) semantic network relation extraction entity linking knowledge reasoning

Recursive Projected Filter Algorithm with Binary-Valued Observations

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Journal of Systems Science & Complexity 2024年第5期37卷 1832-1860页

作者： ZHANG Xiaoyan WANG Ying XUE Wenchao zhao Yanlong Key Laboratory of Systems and Control Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences School of mathematical Sciences University of Chinese Academy of Sciences

This paper focuses on the state estimate for a class of systems with both process noise and measurement noise under binary-valued observations, in which the Gaussian assumption on the predicted density of the state is not required. A recursive projected filter algorithm with time-varying thresholds is constructed to estimate the state under binary-valued observations. The time-varying thresholds are designed as the prediction value of the measurement, which can provide more information about the system state. The convergence property is established with some suitable stability,boundedness and observability conditions. In particular, the estimation error between state and estimate is proved to be asymptotically bounded in the mean-square sense, whose upper bound is related to the variance of process noise. Finally, the theoretical results are demonstrated via numerical examples of first-order and high-order systems.

关键词： Binary-valued observations convergence recursive filter time-varying thresholds

Glacial-interglacial cycles recorded in clay minerals from the eastern Tibetan Plateau over the last 800 ka and their indications

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Science China Earth Sciences 2024年第7期67卷 2162-2177页

作者： Xiaoyan ZHANG Chunxia ZHANG Yan zhao Bin HU Zhengtang GUO Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Clay mineral proxies have been widely used to reconstruct changes in provenance and the ***,high-altitude clay mineral indications and long-term and orbital variations have not been fully ***,we present an800-ka clay-mineral record from a lacustrine sediment core(ZB13-C2)from the Zoige Basin on the eastern Tibetan Plateau(TP).X-ray diffraction and scanning electron microscopy were used to identify the clay mineral assemblages and their micromorphological characteristics of core *** results revealed that the clay minerals in core ZB13-C2 are mainly illite,with small amounts of chlorite,kaolinite,and smectite(including irregular mixed-layers of illite-smectite(I/S)and chloritesmectite(C/S)).The clay mineral assemblages and proxies exhibit three stages of change,which are mainly controlled by the Zoige watershed range under different climate *** watershed was limited to the southeastern region with altitudes ranging from~3500 to~4200 meters above sea level(m a.s.l.),and glacial-interglacial hydraulic erosion controlled the input of bedrock debris during 800-621 ka *** expanded to higher altitudes(~4200 to~4700 m a.s.l.)due to stronger seasonal freezethaw weathering without significant glacial-interglacial variations under a cooling and drying climate during 621-100 ka ***,it expanded to its highest altitudes of~4700 to~5200 m *** of the watershed after 100 ka BP,and hydraulic erosion increased obviously under a warm climate of the interstadial mIS 3 on the *** watershed underwent two major expansions under different climatic conditions at~621 ka and 100 ka BP,with the wet/dry alternation became strong at~621 ka *** results reveal that long-term temperature changes and the wet/dry alternation at high altitudes controlled the watershed range and degree of the physical erosion,and that the indications of clay minerals should be carefully clarified before they are used as climate indicators,especi

关键词： Quaternary Zoige Basin Lacustrine sediments Paleoenvironment Weathering

Living/controlled polymerization of vinylpyridines into sequence-regulated copolymers by Lewis pair

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Science China Chemistry 2024年第8期67卷 2737-2746页

作者： Qiankun Ding Wuchao zhao Fukuan Li Jianghua He Yuetao Zhang Department of State Key Laboratory of Supramolecular Structure and materials College of ChemistryJilin UniversityChangchun 130012China

The poly(vinylpyridine)(PVP) based(co)polymers are of particular interest in materials science, due to their multifunctionality and diverse applications. So far, there is no report on the sequence-regulated copolymerization of vinylpyridines(VPs) and methacrylate monomer in one-step manner yet. Here we designed and synthesized a series of guanidine phosphines as Lewis base(LB), which is combined with bulky organoaluminium to construct Lewis pairs(LPs) for polymerization of VPs. The living/controlled polymerization of 4-vinylpyridine(4-VP) or 2-vinylpyridine(2-VP) can be accomplished with remarkable efficiency by such Lewis pair polymerization(LPP), furnishing polymers with high molecular weight(up to 288 kg/mol) and narrow molecular weight distribution(as low as 1.17). mechanistic studies reveal the interaction of LPs and formation of zwitterionic intermediates, providing solid evidences to support the proposed polymerization mechanism. more importantly, by simply adjusting the LA dosage, this LPP strategy realizes the unprecedented control over the sequence regulation of 2-VP-based copolymers from gradient to block in one-step manner, regardless of the monomer ratio, which greatly expands the versatility of the LPP.

关键词： guanidine phosphine Lewis pair polymerization living/controlled polymerization vinyl pyridine sequence regulation

Polyphyllin Ⅰ enhances tumor necrosis factor-related apoptosis-inducing ligand-induced inhibition of human osteosarcoma cell growth via downregulating the Wnt/β-catenin pathway

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Journal of Traditional Chinese medicine 2024年第2期44卷 251-259页

作者： CHANG Junli zhao Fulai SUN Xingyuan mA Xiaoping zhao Peng ZHOU Chujie SHI Binhao GU Wenchao WANG Yongjun YANG Yanping Spine Disease Institute Longhua Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 200032China Department of Diagnostic and Interventional Radiology University of TsukubaIbaraki 315-0114Japan

OBJECTIVE:To investigate the synergistic effects of polyphyllin Ⅰ(PPⅠ)combined with tumor necrosis factorrelated apoptosis-inducing ligand(TRAIL)on the growth of osteosarcoma cells through downregulating the Wnt/β-catenin signaling ***:Cell viability,apoptosis and cell cycle distribution were examined using cell counting kit-8 and flow cytometry *** morphology of cancer cells was observed with inverted phase contrast *** migration and invasion abilities were examined by xCELLigence real time cell analysis DP system and transwell *** expressions of poly(adenosine diphosphate-ribose)polymerase,C-myc,Cyclin B1,cyclin-dependent kinases 1,N-cadherin,Vimentin,Active-β-catenin,β-catenin,p-glycogen synthase kinase 3β(GSK-3β)and GSK-3βwere determined by Western blotting ***:PPⅠ sensitized TRAIL-induced decrease of viability,migration and invasion,as well as increase of apoptosis and cell cycle arrest of mG-63 and U-2 OS osteosarcoma *** synergistic effect of PPⅠwith TRAIL in inhibiting the growth of osteosarcoma cells was at least partially realized through the inactivation of Wnt/β-catenin signaling ***:The combination of PPⅠ and TRAIL is potentially a novel treatment strategy of osteosarcoma.

关键词： osteosarcoma tumor necrosis factor-related apoptosis-inducing ligand Wnt signaling pathway beta-catenin polyphyllinⅠ