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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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Technical research on optimization design of contacts of electrical connector

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 506-510页

作者： lv Bin ZHOU sheng-jun ZHAO Lan-yan Hangzhou Aerospace Electronic Technology Co. Ltd Hangzhou 310015 China

Pin and socket contacts are the key parts of electrical connector as aerospace electronic components. The contacts are also the direct carriers for signal transmitting of electronic equipments, passing the signal from the input end to the output end of electrical connector. The reliability of pin and socket contacts directly influences signal transmission. The goal of this study is to enhance the contact reliability of aerospace electrical connector. Computer simulation analysis was made on contacts performance data by utilizing the simulation system developed by PCL Language of MSC software. Furthermore, the results were experi- mentally validated so as to realize the objective of optimizing contacts design.

关键词： Electrical connector Contacts Simulation Optimization design

Transforming growth factor-beta 1 enhances discharge activity of cortical neurons

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Neural Regeneration Research 2025年第2期20卷 548-556页

作者： Zhihui Ren Tian Li Xueer Liu Zelin Zhang Xiaoxuan Chen Weiqiang Chen Kangsheng Li Jiangtao sheng Department of Microbiology and Immunology Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular ImmunopathologyShantou University Medical CollegeShantouGuangdong ProvinceChina Department of Neurosurgery First Affiliated Hospital of Shantou University Medical CollegeShantouGuangdong ProvinceChina

Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system *** neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may depend on the pathological process and cell types ***-gated sodium channels(VGSCs)are essential ion channels for the generation of action potentials in neurons,and are involved in various neuroexcitation-related ***,the effects of TGF-β1 on the functional properties of VGSCs and firing properties in cortical neurons remain *** this study,we investigated the effects of TGF-β1 on VGSC function and firing properties in primary cortical neurons from *** found that TGF-β1 increased VGSC current density in a dose-and time-dependent manner,which was attributable to the upregulation of Nav1.3 *** VGSC current density and Nav1.3 expression were significantly abolished by preincubation with inhibitors of mitogen-activated protein kinase kinase(PD98059),p38 mitogen-activated protein kinase(SB203580),and jun NH2-terminal kinase 1/2 inhibitor(SP600125).Interestingly,TGF-β1 significantly increased the firing threshold of action potentials but did not change their firing rate in cortical *** findings suggest that TGF-β1 can increase Nav1.3 expression through activation of the ERK1/2-JNK-MAPK pathway,which leads to a decrease in the firing threshold of action potentials in cortical neurons under pathological ***,this contributes to the occurrence and progression of neuroexcitatory-related diseases of the central nervous system.

关键词： central nervous system cortical neurons ERK firing properties JNK Nav1.3 p38 transforming growth factor-beta 1 traumatic brain injury voltage-gated sodium currents

Output speed and flow of double-acting double-stator multi-pumps and multi-motors

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第4期12卷 301-309页

作者： De-sheng WEN Zhi-li WANG jun GAO Yong ZHANG Shi-jun lv Tetsuhiro TSUKIJI College of Mechanical Engineering Yanshan University Qinhuangdao 066004 China College of Engineering and Applied Science Sophia University Tokyo 102-8554 Japan

The primary focus of this study was to investigate a series of novel motors and pumps,based on a new type of structure called *** double-stator structure can be used as pump or motor just based on the application requirements.A certain amount of pumps or motors can be formed in one shell,and these sub-pumps or sub-motors can work alone or be combined without influence on each *** this kind of double-stator pump(motor) is called a multi-pump(multi-motor).Through the analysis of multifarious connection modes of the double-acting double-stator multi-pumps and multi-motors,the mathematical expressions of the output flow rate and the rotational speed are *** results indicate that a quantity of different flow rates can be provided by one fixed-displacement multi-pump under the condition of unalterable driven speed by ***,when supplied by settled input flow,without complex variable mechanism,the functions of double-speed,multiple-speed,and even differential connection can be obtained by employing the use of a double-stator *** novel hydraulic transmission is made of such a double-stator multi-pump and multi-motor,and has broad application prospects.

关键词： Multi-pumps Multi-motors Flow rate Rotational speed Hydraulic transmission Differential motor

A Patch-Based Low-Rank Minimization Approach for Speckle Noise Reduction in Ultrasound Images

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Advances in Applied Mathematics and Mechanics 2022年第1期14卷 155-180页

作者： Xiao-Guang lv Fang Li jun Liu sheng-Tai Lu School of Science Jiangsu Ocean UniversityLianyungangJiangsu 222005China Shanghai Key Laboratory of PMMP and School of Mathematical Sciences East China Normal UniversityShanghai 200241China School of Mathematics and Statistics and Key Laboratory of Applied Statistics of MOE Northeast Normal UniversityChangchunJilin 130024China

Ultrasound is a low-cost,non-invasive and real-time imaging modality that has proved popular for many medical ***,the acquired ultrasound images are often corrupted by speckle noise from scatterers smaller than ultrasound beam *** signal-dependent speckle noise makes visual observation *** this paper,we propose a patch-based low-rank approach for reducing the speckle noise in ultrasound *** constructing the patch group of the ultrasound images by the block-matching scheme,we establish a variational model using the weighted nuclear norm as a regularizer for the patch *** alternating direction method of multipliers(ADMM)is applied for solving the established nonconvex *** return all the approximate patches to their original locations and get the final restored ultrasound *** results are given to demonstrate that the proposed method outperforms some existing state-of-the-art methods in terms of visual quality and quantitative measures.

关键词： Ultrasound images patch speckle noise low-rank weighted nuclear norm minimization

Recent advances in direct dehydrogenative biphenyl couplings

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Science China Chemistry 2017年第6期60卷 701-720页

作者： Fei lv Zhu-jun Yao State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringCollaborative Innovation Center of Chemistry for Life ScieneesNanjing UniversityNanjing 210023China

Biphenyl moiety represents a unique structural motif of many natural and unnatural products with biological interests, and dehydrogenative couplings of two aryl C–H bonds under oxidative conditions is unambiguously the most efficient and direct preparation of these compounds. However, higher oxidation potential of benzene derivatives makes such oxidative couplings much more difficult than other arenes. Only very limited advances have been achieved on direct formation of the crucial C–C bond between two phenyl derivatives by dehydrogenative phenyl coupling in the last two decades. This article briefly summarized and commented a number of representative recent achievements in this attractive field, including homo-, cross-and intramolecular rearrangement and couplings, as well as their applications in organic synthesis.

关键词： biphenyl dehydrogenative coupling oxidation arene C–H bond activation

L^(p)Solution of Reflected BSDEs with One Continuous Barrier and Quasi-linear Growth Generators

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Acta Mathematicae Applicatae Sinica 2024年第4期40卷 943-953页

作者： sheng-jun FAN School of Mathematics China University of Mining and TechnologyXuzhou 221116China

This paper is devoted to solving a reflected backward stochastic differential equation(BSDE in short)with one continuous barrier and a quasi-linear growth generator g,which has a linear growth in(y,z),except the upper direction in case of y1)solutions for the reflected *** also prove that the minimal Lpsolution can be approximated by a sequence of Lpsolutions of certain reflected BSDEs with Lipschitz generators.

关键词： Reflected BSDEs Quasi-linear growth L^(p)solution Existence Comparison theorem

Artificial neural network algorithm for pulse shape discrimination in 2πα and 2πβ particle surface emission rate measurements

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Nuclear Science and Techniques 2023年第10期34卷 91-102页

作者： Yuan-Qiao Li Bao-Ji Zhu Yang lv Heng Zhu Min Lin Ke-sheng Chen Li-jun Xu China Institute of Atomic Energy Beijing 102413China National Key Laboratory for Metrology and Calibration Techniques Beijing 102413China

To enhance the accuracy of 2πα and 2πβ particle surface emission rate measurements and address the identification issues of nuclides in conventional methods, this study introduces two artificial neural network(ANN) algorithms: back-propagation(BP) and genetic algorithm-based back-propagation(GA-BP). These algorithms classify pulse signals from distinct α and β particles. Their discrimination efficacy is assessed by simulating standard pulse signals and those produced by contaminated sources, mixing α and β particles within the detector. This study initially showcases energy spectrum measurement outcomes, subsequently tests the ANNs on the measurement and validation datasets, and contrasts the pulse shape discrimination efficacy of both algorithms. Experimental findings reveal that the proportional counter's energy resolution is not ideal, thus rendering energy analysis insufficient for distinguishing between 2πα and 2πβ particles. The BP neural network realizes approximately 99% accuracy for 2πα particles and approximately 95% for 2πβ particles, thus surpassing the GA-BP's performance. Additionally, the results suggest enhancing β particle discrimination accuracy by increasing the digital acquisition card's threshold lower limit. This study offers an advanced solution for the 2πα and 2πβ surface emission rate measurement method, presenting superior adaptability and scalability over conventional techniques.

关键词： Pulse shape discrimination Artificial neural networks Alpha and beta sources Multi-wire proportional counter Surface emission rate

The Influence of Ultrasonic Frequency on the Properties of Ni-Co Coatings Prepared by Ultrasound-assisted Electrodeposition

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Acta Metallurgica Sinica(English Letters) 2013年第6期26卷 735-741页

作者： Minqi sheng Chenkai lv Lan HONG Mingwang SHAO Kang WAN Fan lv School of Iron and Steel Soochow University Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University

In this paper, Ni-Co coatings were electrodeposited onto carbon steel substrates with the aid of ultrasonic agitation. The coatings were analyzed by energy dispersive X-ray analysis （EDX）, X-ray diffraction analysis （XRD） and scanning electron microscopy （SEM）. The effects of the ultrasonic frequency on the roughness, hardness and corrosion resistance of the Ni-Co coatings were also investigated. The results indicated that the increase of the ultrasonic frequency from 20 to 120 kHz reduced the Ni content and the grain size of Ni-Co coatings. Moreover, the phase structure of the electrodeposited coatings was influenced by the ultrasonic frequency. Under 55 kHz ultrasonic agitation, the Ni-Co coating was single fcc phase and showed the finest roughness and the strongest corrosion resistance in 5 wt.% NaCl solution at the ambient temperature. Under ultrasonic agitation with frequency of 90 kHz, the coating was a mixture of fcc and hcp structure and showed the maximal hardness of about 420 HV. Therefore, ultrasonic agitation helped decrease the roughness, and enhance hardness and corrosion resistance of Ni-Co coatings.

关键词： Ni-Co alloys Coatings Electrodeposition Ultrasound Hardness Corrosion