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Transient chemical-mediated epigenetic modulation confers unrestricted lineage potential on human primed pluripotent stem cells

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Science China life Sciences 2025年

作者： Shi Chen Yuanyuan He lejun lv Bei liu Cheng li Hongkui Deng jun Xu Department of Cell Biology School of Basic Medical Sciences Peking University Stem Cell Research Center Peking University Health Science Center Peking University Academy of Advanced Interdisciplinary Studies Peking University BeiCell Therapeutics School of life Sciences Center for Bioinformatics Center for Statistical Science Peking University MOE Engineering Research Center of Regenerative Medicine School of Basic Medical Sciences State Key Laboratory of Natural and Biomimetic Drugs Peking University Health Science Center and the MOE Key Laboratory of Cell Proliferation and Differentiation College of Life Sciences Peking-Tsinghua Center for Life Sciences Peking University

Human primed pluripotent stem cells are capable of generating all the embryonic ***,their extraembryonic trophectoderm potentials are *** remains unclear how to expand their developmental potential to trophectoderm *** we show that transient treatment with a cocktail of small molecule epigenetic modulators imparts trophectoderm lineage potentials to human primed pluripotent stem cells while preserving their embryonic *** chemically treated cells can generate trophectoderm-like cells and downstream trophoblast stem cells,diverging into syncytiotrophoblast and extravillous trophoblast *** and CUT&Tag analyses reveal that these induced cells share transcriptional profiles with in vivo trophectoderm and cytotrophoblast,and exhibit reduced H3K27me3 modification at gene loci specific to trophoblast lineages compared with primed pluripotent *** exploration highlighted the critical roles of epigenetic modulators HDAC2,EZH1/2,and KDM5s in the activation of trophoblast lineage *** findings demonstrate that transient epigenetic resetting activates unrestricted lineage potential in human primed pluripotent stem cells,and offer new mechanistic insights into human trophoblast lineage specification and in vitro models for studying placental development and related disorders.

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left Invertible Completions of Upper Triangular Operator Matrices with Unbounded Entries

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Acta Mathematicae Applicatae Sinica 2015年第2期31卷 369-374页

作者： ya-ru QI jun-jie HUANG AlATANCANG School of Mathematical Sciences Inner Mongolia University College of Sciences Inner Mongolia University of Technology Hohhot University for Nationalities

Given two closed, in general unbounded, operators A and C, we investigate the left invertible completion of the partial operator matrix A ？ 0 C. Based on the space decomposition technique, the alternative sufficient and necessary conditions are given according to whether the dimension of R（A）⊥ is finite or *** a direct consequence, the perturbation of left spectra is further presented.

关键词： upper triangular operator matrix left invertibility completion perturbation left spectrum

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Calculation of Total Cross Section for Positron Scattering on Helium

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Chinese Physics letters 1998年第3期15卷 180-182页

作者： ZHOU ya-jun PAN Shou-fu Institute of Atomic and Molecular Physics National Laboratory of Theoretical and Computational ChemistryJilin UniversityChangchun 130023

Total scattering cross sections for positron scattering on helium are calculated at intermediate energies and compared with experimental *** method used is the coupled-channels-optical method with an ab initio complex polarization potential,which takes all channels into *** results show that the ionization continuum and positronium formation rearrangment channels are very important parts in total scattering cross section of positron-helium collision.

关键词： positron collision method

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Positronium Formation in Positron-lithium Scattering

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Chinese Physics letters 2011年第12期28卷 117-119页

作者： CHENG Yong-jun ZHOU ya-jun lIU Fang Natural Science Research Center the Academy of Fundamental and Interdisciplinary ScienceHarbin Institute of TechnologyHarbin 150080

The positronium formation process in positron scattering with atomic lithium is investigated using the coupled-channel optical *** cross sections of positronium formation into the n=1 and n=2 levels from 2 to 60 eV are *** present results show reasonable agreement with the available experimental measurements and theoretical calculations.

关键词： method lithium positronium

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Positron Impact Ionization of Hydrogen, Sodium, and Potassium

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Chinese Physics letters 1997年第5期14卷 348-351页

作者： ZHOU ya-jun PAN Shou-pu Institute of Atomic and Molecular Physics National Laboratory of Theoretical and Computational ChemistryJilin UniversityChangchun 130023

The total ionization cross sections for positron scattering by hydrogen,sodium,and potassium are calculated by applying an equivalent-local optical potential model from the ionization threshold to *** total ionization cross sections are in excellent agreement with the recent measurements of Jones et *** total ionization cross sections for sodium and potassium are compared with other theoretical calculations.

关键词： potassium ionization applying

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Fractal growth kinematics abstracted from snowflakes:topological evolution

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Applied Mathematics and Mechanics(English Edition) 2015年第2期36卷 243-264页

作者： Fan yaNG ya jun YIN Bin HE Qinshan FAN Department of Engineering Mechanics School of Aerospace Key Laboratory of Applied Mechanics Tsinghua University Division of Mechanics Nanjing University of Technology

Based on the kinematic viewpoint, the concept of proportional movement is abstracted to explain the strange behaviors of fractal snowflakes. A transformation group for proportional movement is defined. Under the proportional movement transformation groups, necessary and sufficient conditions for self-similarity of multilevel structures are presented. The characteristic topology of snowflake-like fractal patterns, identical to the topology of ternary-segment fractal line, is proved. Moreover, the topological evolution of N-segment line is explored. The concepts of limit growth and infinite growth are clarified,and the corresponding growth conditions are derived. The topological invariant properties of N-segment line are exposed. In addition, the proposition that the topological evolution of the N-segment line is mainly controlled by the topological invariant N is verified.

关键词： fractal snowflake proportional movement self-similarity N-segment line topological evolution and topological invariant

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Investigation on influence of drilling unloading on wellbore stability in clay shale formation

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Petroleum Science 2020年第3期17卷 781-796页

作者： Yi Ding Xiang-jun liu Ping-ya luo State Key laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500SichuanPeople's Republic of China Deep Earth Energy lab Department of Civil EngineeringMonash UniversityMelbourne 3800Australia

Wellbore collapse frequently happens in the clay shale *** maintain wellbore stability,appropriate mud pressure is a vital *** clay formation is opened,drilling unloading occurs,modifying rock structure and strength at the wall of borehole,which affects the selection of mud ***,mechanism of drilling unloading is still poorly understood which in return will bring a concern to wellbore ***,in this study,a combination of triaxial compressive test and ultrasonic wave test has been used to simulate drilling unloading and analyze its *** indicate that more void space is created inside the clay shale sample due to *** structure change leads to a decline of strength and acoustic ***,unloading influence is depended on varying drilling unloading *** unloading range and fast unloading rate are able to enhance *** various degrees of unloading impact,collapse pressure equivalent density has a clear modification,proving that unloading is a non-negligible influencing factor of wellbore ***,the unloading effect is much stronger in large confining pressure,implying that more attention should be given to unloading when drilling is in extreme deep or high geostress *** in this paper can offer theoretical guidance for drilling in the clay shale formation.

关键词： Drilling unloading Clay shale Wellbore stability Rock strength

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Extraction of yarn positional information from three-dimensional CT image of textile fabric using a yarn model for its structure analysis

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仪器仪表学报 2008年第8期29卷 1569-1576页

作者： Toshihiro Shinohara jun-ya Takayama Shinji Ohyama Akira Kobayashi School of Biology-Oriented Science and Technology Kinki University Kinokawa-shi Wakayama-kenJapan Graduate School of Science and Engineering Tokyo Institute of Technology1-12-1 Meguro-kuTokyoJapan Faculty of University Evaluation and Research National Institution for Academic Degrees and UniversityEvaluation Kodaira-shi TokyoJapan

This paper proposes a novel method for analyzing a textile fabric structure to extract positional information regarding each yarn using three-dimensional X-ray computed tomography(3D CT) *** relationship among the yarns can be reconstructed using the extracted yarn positional *** this paper,a sequence of points on the center line of each yarn of the sample is defined as the yarn positional information,since the sequence can be regarded as the representative position of the *** sequence is extracted by tracing the *** yarn is traced by estimating the yarn center and direction and correlating the yarn part of the 3D CT image with a 3D yarn model,which is moved along the estimated yarn *** trajectory of the center of the yarn model corresponds to the positional information of the *** application of the proposed method is shown by experimentally applying the proposed method to a 3D CT image of a double-layered woven ***,the experimental results for a plain knitted fabric show that this method can be applied to even knitted fabrics.

关键词：纺织品 CT影像分析方法物理结构

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A Novel Multiscale Reinforcement by In-Situ Growing Carbon Nanotubes on Graphene Oxide Grafted Carbon Fibers and Its Reinforced Carbon/Carbon Composites with Improved Tensile Properties

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Journal of Materials Science & Technology 2016年第5期32卷 419-424页

作者： Yunyu li ling-jun Guo ya-wen Wang He-jun li Qiang Song State Key laboratory of Solidification Processing Northwestern Polytechnical University Center for Nano Energy Materials Northwestern Polytechnical University

In-situ growing carbon nanotubes （CNTs） directly on carbon fibers （CFs） always lead to a degraded tensile strength of CFs and then a poor fiber-dominated mechanical property of carbon/carbon composites （C/ Cs）. To solve this issue, here, a novel carbon fiber-based multiscale reinforcement is reported. To synthesize it, carbon fibers （CFs） have been first grafted by graphene oxide （GO）, and then carbon nanotubes （CNTs） have been in-situ grown on GO-grafted CFs by catalytic chemical vapor deposition. Characterizations on this novel reinforcement show that GO grafting cannot only nondestructively improve the surface chemical activity of CFs but also protect CFs against the high-temperature corrosion of metal catalyst during CNT growth, which maintains their tensile properties. Tensile property tests for unidirectional C/Cs with different preforms show that this novel reinforcement can endow C/C with improved tensile properties, 32% and 87% higher than that of pure C/C and C/C only doped with in-situ grown CNTs. This work would open up a possibility to fabricate multiscale C/Cs with excellent global performance.

关键词： Multiscale reinforcement Carbon fiber Graphene oxide Carbon nanotube Carbon/carbon composite Tensile property

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Moment Redistribution Effect of the Continuous Glass Fiber Reinforced Polymer-Concrete Composite Slabs Based on Static loading Experiment

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Structural Durability & Health Monitoring 2025年第1期19卷 105-123页

作者： Zhao-jun Zhang Wen-Wei Wang Jing-Shui Zhen Bo-Cheng li De-Cheng Cai yang-yang Du Hui Huang Offshore Oil Engineering Co.ltd. Tianjin300461China Department of Bridge Engineering School of TransportationSoutheast UniversityNanjing211189China

This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment *** experimental bending moment redistribution test was conducted on continuous GFRP-concrete composite slabs,and a calculation method based on the conjugate beam method was *** composite slabs were formed by combining GFRP profiles with a concrete layer and supported on steel beams to create two-span continuous composite slab *** methods,epoxy resin bonding,and stud connection,were used to connect the composite slabs with the steel *** experimental findings showed that the specimen connected with epoxy resin exhibited two moments redistribution phenomena during the loading process:concrete cracking and steel bar yielding at the internal *** contrast,the composite slab connected with steel beams by studs exhibited only one-moment redistribution phenomenon throughout the loading *** the concrete at the internal support cracked,the bending moment decreased in the internal support section and increased in the midspan *** the steel bars yielded,the bending moment further decreased in the internal support section and increased in the mid-span *** GFRP profiles do not experience cracking,there was no significant decrease in the bending moment of the mid-span *** test specimens experienced compressive failure of concrete at the mid-span *** results showed good agreement between the calculated and experimental values of bending moments in the mid-span section and internal support *** proposed model can effectively predict the moment redistribution behavior of continuous GFRP-concrete composite slabs.

关键词： Moment redistribution GFRP-concrete composite slabs bending moment experimental study analysis model

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