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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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略论唐代宰相制度

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史学集刊 2025年第1期 88-97页

作者：孟宪实中国人民大学历史学院北京100872

在中国古代政治制度史中,宰相制度无疑是一个重要课题。众所周知,在讨论中国的皇帝制度时,有一个重要的观点是讨论“君权”与“相权”的斗争,而君权的不断增长、相权的不断被削弱,正是君主专制持续发展的重要途径。事实上,各个时期的宰... 详细信息

在中国古代政治制度史中,宰相制度无疑是一个重要课题。众所周知,在讨论中国的皇帝制度时,有一个重要的观点是讨论“君权”与“相权”的斗争,而君权的不断增长、相权的不断被削弱,正是君主专制持续发展的重要途径。事实上,各个时期的宰相制度既有变迁,又各具特色,从每个朝代的宰相制度是否能够得出君主专制获得发展的结论,显然是需要具体论证的。唐代宰相制度的研究,通常是在三省制的背景下展开的,而唐代的宰相制度也有自己的发展变化。唐代宰相制度经过三个历史时期,政事堂时期是兼职宰相时期,中书门下时期是专职宰相时期。自唐后期至北宋,是首相制时期。唐代宰相制度的变化,是不是君相斗争的结果?而从兼职宰相到专职宰相再到首相制,宰相的职权明显是处在加强的进程中,按照君相斗争的习惯思路,难道是君主在君相斗争中败下阵来?恐怕不能得出这样的结论。此外,唐宋历史的关系,向来有“唐宋变革论”,强调唐宋之别,但从宰相制度来看,唐宋历史的联系性似乎更突出。

关键词：唐代政事堂中书门下首相制

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习近平关于新质生产力重要论述的理论体系和实践指向研究

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新疆师范大学学报（哲学社会科学版） 2025年第1期46卷 60-68页

作者：方世南苏州大学东吴智库苏州大学马克思主义学院江苏省习近平新时代中国特色社会主义思想研究中心苏州大学基地江苏苏州215006

习近平总书记关于新质生产力重要论述深刻阐明了新质生产力的基本内涵、本质特征、鲜明标志、核心要素、形成规律以及实现路径等重大理论和实践问题,是具有重大原创性、标识性、系统性、实践性的理论创新成果,是习近平新时代中国特色社... 详细信息

习近平总书记关于新质生产力重要论述深刻阐明了新质生产力的基本内涵、本质特征、鲜明标志、核心要素、形成规律以及实现路径等重大理论和实践问题,是具有重大原创性、标识性、系统性、实践性的理论创新成果,是习近平新时代中国特色社会主义思想的重要组成部分。习近平总书记关于新质生产力重要论述是在推进中国式现代化进程中形成的新的生产力理论,是指导我国经济社会高质量发展的学理化、体系化的理论体系,是具有深邃而丰富辩证法则的实践指向。

关键词：中国式现代化新质生产力重要论述理论体系实践指向

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含孔洞CoCrNiFeCu高熵合金纳米压入的分子动力学模拟

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原子与分子物理学报 2025年第3期42卷 141-148页

作者：史银花施琴江苏联合职业技术学院镇江分院镇江212016

高熵合金具有优异的力学性能、耐磨耐蚀耐高温等性能,成为未来最有发展潜力的新型材料之一.因此,本文通过分子动力学模拟的方法探究了孔洞对CoCrNiFeCu高熵合金模型纳米压痕力学性能和位错演化的影响.结果表明,屈服点、载荷、杨氏模量... 详细信息

高熵合金具有优异的力学性能、耐磨耐蚀耐高温等性能,成为未来最有发展潜力的新型材料之一.因此,本文通过分子动力学模拟的方法探究了孔洞对CoCrNiFeCu高熵合金模型纳米压痕力学性能和位错演化的影响.结果表明,屈服点、载荷、杨氏模量和硬度等力学参数随着孔洞深度D的增加呈现先增加后稳定的趋势.孔洞的存在显著影响了位错形核的位置,随着孔洞深度的增加,初始位错优先在孔洞与表面之间形成,随后集中在模型表面形成,且位错环由平面圆环状转变为“翼状”.在孔洞深度较小时(D<40A),位错环沿(110)面水平扩展,随着孔洞深度的增加,位错环开始向下扩展.此外,在压痕深度为30?时,位错密度随着孔洞深度的增加逐渐增加.

关键词： CoCrNiFeCu 分子动力学纳米压入力学性能位错演变

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Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

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Science China Chemistry 2025年第1期68卷 233-240页

作者： Peipei Liu Yantong Li Meng-Xiang Wu Hao Kang Xiao-Li Zhao Lin Xu Linlin Liu Xiaodong Li Junfeng Fang Zhiwei Fang Ya Cheng Hai-Bo Yang Huakang Yu Xueliang shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词： double carbohelicene optical resolution organic laser isomerization X-ray diffraction

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D-DeepOCSORT: multi-object tracking algorithm based on LiDAR and monocular camera

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Optoelectronics Letters 2025年

作者： HE Xiao REN Shuai LIU Chang shi Lei School of Information Engineering， Chang'an University School of Control of Robotic and Autonomous Systems， University of California Berkeley

Multi-object tracking is a fundamental problem in computer vision， and DeepOCSORT， due to its reliance on the 2D image position information of targets， tends to exhibit prediction drift. To enhance the tracking stability of DeepOCSORT， this paper proposes a novel multi-sensor data fusion-based multi-object tracking method. Specifically， we build upon the DeepOCSORT foundation and additionally integrate target velocity information directly measured by LiDAR. The introduction of this velocity information is conducted from three perspectives: firstly， during data association， a penalty term is constructed based on the differences in target velocities to constrain generating matches with consistent velocities; secondly， using LiDAR velocity for initialization and online updating of the velocity state within the tracker， making tracking predictions more stable; thirdly， controlling the degree of dependence on velocity information by adjusting the process noise covariance matrix. Evaluation results on the KITTI dataset demonstrate that compared to the original DeepOCSORT， the proposed improved multi-source heterogeneous information fusion method significantly enhances tracking performance， with maximum improvements of 3.35， 3.26， and 3.71 on the HOTA， MOTA， and IDF1 metrics， respectively. This study provides an effective approach to building a more stable and accurate multi-object tracking system.

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Steel surface defect detection based on lightweight YOLOv7

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Optoelectronics Letters 2025年

作者： shi Tao Wu Rongxin Zhu Wenxu Ma Qingliang School of Electrical Engineering and Automation， Tianjin University of Technology North China University of Science and Technology， College of Electrical Engineering Guangzhou Institute of Measurement and Testing Technology

Aiming at the problems of low detection efficiency and difficult positioning of traditional steel surface defect detection methods， a lightweight steel surface defect detection model based on YOLOv7 is proposed. First， a CSS Block module is proposed， which uses more lightweight operations to obtain redundant information in the feature map， reduces the amount of computation， and effectively improves the detection speed. Secondly， the improved SPPCSPC structure is adopted to ensure that the model can also pay attention to the defect location information while predicting the defect category information， obtain richer defect features. In addition， the convolution operation in the original model is simplified， which significantly reduces the size of the model and helps to improve the detection speed. Finally， using EIOU Loss to focus on high-quality Anchors， speed up convergence and improve positioning accuracy. Experiments were carried out on the NEU-DET steel surface defect dataset. Compared with the original YOLOv7 model， the number of parameters of this model was reduced by 40%， the FPS reached 112， and the average accuracy reached 79.1%.， the detection accuracy and speed have been improved， which can meet the needs of steel surface defect detection.

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EBD-YOLO：a lightweight auxiliary driving detection algorithm based on YOLOv5

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Optoelectronics Letters 2025年

作者： SUN Lianshuai shi Tao DING Yao LI Song Tianjin Key Laboratory for Control Theory and Applications in Complicated Systems， School of Electrical Engineer-ing and Automation， Tianjin University of Technology College of Electrical Engineering， North China University of Science and Technology

A lightweight road-assistant detection algorithm， EBD-YOLO， based on YOLOv5s is proposed to address the problems of high model complexity， computation cost， and difficulty in deployment on resource-limited embedded terminals in existing assisted driving detection algorithms. First， lightweight Transformer model EfficientViT was used as the backbone feature extraction network of YOLOv5s model to reduce network parameters and calculation costs. Secondly， a Focal-GIoU Loss function is proposed for bounding box regression to accelerate model convergence and reduce loss. Thirdly， the feature pyramid structure is improved to a weighted bi-directional feature pyramid network (BiFPN) to enhance localization and semantic features. Then， a dynamic head framework is added to unify the attention mechanism with the object detection head to improve its performance. Finally， a Soft-CIoU＿NMS algorithm is proposed in the post-processing stage to enhance occluded targets' localization and detection ability and reduce the missed detection rate. We conducted experiments on the KITTI and BDD100K datasets for autonomous driving， and the results showed that the EBD-YOLO model reduced in size by 38.4% and 37.2%， respectively. In comparison， the computational cost was reduced by 48.1%. As measured by mAP@0.5， the detection accuracy improved by 0.5% and 5.8%， respectively， and mAP@0.5:0.95 improved by 2.8% and 7%， respectively. These improvements satisfied the requirements for deployment on embedded terminals in cars.

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3D Printing of Tough Hydrogel Scaffolds with Functional Surface Structures for Tissue Regeneration

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Nano-Micro Letters 2025年第2期17卷 18-45页

作者： Ke Yao Gaoying Hong Ximin Yuan Weicheng Kong Pengcheng Xia Yuanrong Li Yuewei Chen Nian Liu Jing He Jue shi Zihe Hu Yanyan Zhou Zhijian Xie Yong He State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Liangzhu Laboratory Zhejiang UniversityHangzhou 310027People’s Republic of China Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province College of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Stomatology Hospital School of StomatologyZhejiang University School of MedicineHangzhou 310027People’s Republic of China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001People’s Republic of China Institute of Digital Medicine Nanjing First HospitalNanjing Medical UniversityNanjing 210006People’s Republic of China

Hydrogel scaffolds have numerous potential applications in the tissue engineering ***,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical *** by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this ***,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent ***,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell ***,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT *** experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.

关键词： 3D printing Tough hydrogel scaffold Functional surface structure Tissue regeneration Biomaterials

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Wetland and habitat dynamics in the evolving landscape of the Middle Yangtze River Basin

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Journal of Geographical Sciences 2025年第1期35卷 88-111页

作者： YANG Peng SUN Kaiya ZHU Yanchao XIA Jun HUANG Heqing SONG Jingxia shi Xiaorui LU Xixi Hubei Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information Engineering China University of Geosciences Department of Geography National University of Singapore State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University

Wetlands play a critical role in the global environment. The Middle Yangtze River Basin(MYRB), known for its abundant wetland resources, has experienced notable changes resulting from the complex interplay of environmental factors. Therefore, we investigated the spatiotemporal characteristics of wetland ecological quality in the MYRB from 2001 to *** the random forest(RF) regression algorithm and patch-generated land-use simulation(PLUS) model, we forecasted variations in wetland habitat quality and their determinants under the Shared Socioeconomic Pathway-Representative Concentration Pathway(SSPRCP) framework from 2035 to 2095. The main findings are as follows:(1) The RF algorithm was optimal for land-use and land-cover(LULC) classification in the MYRB from 2001 to 2020,when notable changes were observed in water bodies and buildings. However, the forested area exhibited an increase and decrease of 3.9% and 1.2% under the SSP1-2.6 and SSP5-8.5 scenarios, respectively, whereas farmland exhibited a diminishing trend.(2) Wetlands were primarily concentrated in the central and eastern MYRB, with counties in the southwest exhibiting superior ecological-environmental quality from 2001 to 2020. Notably,wetland coverage revealed significantly high level, significant changes, frequent but relatively minor changes under the SSP1-2.6, SSP2-4.5, and SSP 5-8.5 scenarios, respectively.(3)Regions with lower habitat quality were primarily concentrated in urbanized areas characterized by frequent human activities, indicating a clear degradation in habitat quality across different scenarios. In conclusion, we established a foundational framework for future investigations into the eco-hydrological processes and ecosystem quality of watersheds.

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