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Regulation of intestinal stem cell fate specification

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Science China(Life Sciences) 2015年第6期58卷 570-578页

作者： QI Zhen chen ye-guang State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua-Peking Center for Life Sciences School of Life SciencesTsinghua University

The remarkable ability of rapid self-renewal makes the intestinal epithelium an ideal model for the study of adult stem cells. The intestinal epithelium is organized into villus and crypt, and a group of intestinal stem cells located at the base of crypt are responsible for this constant self-renewal throughout the life. Identification of the intestinal stem cell marker Lgr5, isolation and in vitro culture of Lgr5+ intestinal stem cells and the use of transgenic mouse models have significantly facilitated the studies of intestinal stem cell homeostasis and differentiation, therefore greatly expanding our knowledge of the regulatory mechanisms underlying the intestinal stem cell fate determination. In this review, we summarize the current understanding of how signals of Wnt, BMP, Notch and EGF in the stem cell niche modulate the intestinal stem cell fate.

关键词： intestinal stem cells Wnt BMP Notch EGF fate specification

Regulation of embryonic stem cell self-renewal and differentiation by TGF-β family signaling

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Science China(Life Sciences) 2010年第4期53卷 497-503页

作者： FEI Teng & chen ye-guang The State Key Laboratory of Biomembrane and Membrane Biotechnology, School of Life Sciences, Tsinghua University, Beijing 100084, China 1. The State Key Laboratory of Biomembrane and Membrane Biotechnology School of Life Sciences Tsinghua University Beijing 100084 China

Embryonic stem (ES) cells are characterized by their ability to indefinitely self-renew and potential to differentiate into all the cell lineages of the body. ES cells are considered to have potential applications in regenerative medicine. In particular, the emergence of an ES cell analogue-induced pluripotent stem (iPS) cells via somatic cell reprogramming by co-expressing a limited number of critical stemness-related transcriptional factors has solved the problem of obtaining patient-specific pluripotent cells, encouraging researchers to develop more specific and functional cell lineages from ES or iPS cells for broad therapeutic applications. ES cell fate choice is delicately controlled by a core transcriptional network, epigenetic modification profiles and complex signaling cascades both intrinsically and extrinsically. Of these signals, transforming growth factor β (TGF-β) family members, including TGF-β, bone morphogenetic protein (BMP), Activin and Nodal, have been reported to influence cell self-renewal and a broad spectrum of lineage differentiation in ES cells, in accordance with the key roles of TGF-β family signaling in early embryo development. In this review, the roles of TGF-β family signals in coordinating ES cell fate determination are summarized.

关键词： embryonic stem cell TGF-β BMP Activin Nodal self-renewal differentiation

Correlation between grain size,mechanical properties and deformed microstructure of Fe-20Mn-6Al-0.6C-0.15Si low-density steel

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Journal of Iron and Steel Research International 2025年第1期32卷 282-292页

作者： Qi Zhang guang-hui chen Zheng-liang Xue Zheng-kun chen guang Xu State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan430081HubeiChina Red Eagle Novel Refractory Materials Research Institute Zhejiang Red Eagle Group Co.Ltd.Huzhou313000ZhejiangChina

The effects of austenite grain size on the deformed microstructure and mechanical properties of an Fe-20Mn-6Al-0.6C-0.15Si(wt.%)low-density steel were *** microstructure of the experimental steel after solution treatment was single austenitic *** austenite grain size increased with solution temperature and time.A model was established to show the relationship between temperature,time and austenite grain size for the experimental *** addition,as the solution temperature increased,the strength decreased,while the elongation first increased and then *** decrease in elongation after solution treatment at 1100℃ for 90 min is contributed to the over-coarse austenite ***,after solution treatment at 900℃ for 90 min,the strength-elongation product reached the highest value of 44.4 GPa%.As the austenite grain size increased,the intensity of//tensile direction fiber *** was accompanied by a decrease in dislocation density,resulting in a lower fraction of low-angle grain boundaries and a lower work hardening ***,the austenite grain size has a critical influence on the mechanical properties of the low-density *** grains lead to a lower yield strength due to the Hall-Petch effect and a lower tensile strength because of lower dislocation strengthening.

关键词： Austenitic low-density steel Solution treatment Grain size Mechanical property Deformed microstructure

Privacy Distributed Constrained Optimization Over Time-Varying Unbalanced Networks and Its Application in Federated Learning

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 335-346页

作者： Mengli Wei Wenwu Yu Duxin chen Mingyu Kang guang cheng the School of Cyber Science and Engineering Southeast University IEEE the School of Mathematics Frontiers Science Center for Mobile Information Communication and Security Southeast University the Purple Mountain Laboratories the School of Mathematics Southeast University

This paper investigates a class of constrained distributed zeroth-order optimization(ZOO) problems over timevarying unbalanced graphs while ensuring privacy preservation among individual agents. Not taking into account recent progress and addressing these concerns separately, there remains a lack of solutions offering theoretical guarantees for both privacy protection and constrained ZOO over time-varying unbalanced *** hereby propose a novel algorithm, termed the differential privacy(DP) distributed push-sum based zeroth-order constrained optimization algorithm(DP-ZOCOA). Operating over time-varying unbalanced graphs, DP-ZOCOA obviates the need for supplemental suboptimization problem computations, thereby reducing overhead in comparison to distributed primary-dual methods. DP-ZOCOA is specifically tailored to tackle constrained ZOO problems over time-varying unbalanced graphs,offering a guarantee of convergence to the optimal solution while robustly preserving privacy. Moreover, we provide rigorous proofs of convergence and privacy for DP-ZOCOA, underscoring its efficacy in attaining optimal convergence without constraints. To enhance its applicability, we incorporate DP-ZOCOA into the federated learning framework and formulate a decentralized zeroth-order constrained federated learning algorithm(ZOCOA-FL) to address challenges stemming from the timevarying imbalance of communication topology. Finally, the performance and effectiveness of the proposed algorithms are thoroughly evaluated through simulations on distributed least squares(DLS) and decentralized federated learning(DFL) tasks.

关键词： Constrained distributed optimization decentralized federated learning (DFL) differential privacy (DP) time-varying unbalanced graphs zeroth-order gradient

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一种基于维纳滤波去除语音通信中混响的方法

上海交通大学学报 2009年第6期43卷 949-952页

作者：张德会陈光冶上海交通大学水声研究室上海200030

简要叙述了语音通信中去混响的意义.利用常规通话起始语音的习惯特点,提出了预存起始纯净语音信号,并基于维纳滤波原理,通过反卷积运算求出房间冲击响应,再通过反卷积去除语音信号混响的新方法.对语音样本的仿真试验表明,该方法对单字... 详细信息

简要叙述了语音通信中去混响的意义.利用常规通话起始语音的习惯特点,提出了预存起始纯净语音信号,并基于维纳滤波原理,通过反卷积运算求出房间冲击响应,再通过反卷积去除语音信号混响的新方法.对语音样本的仿真试验表明,该方法对单字语音的去混响效果良好,在普通计算机上每字的去混响运算耗时为0.3-0.5 s.

关键词：去混响维纳滤波反卷积语音通信

Hausdorff Measure of Space Anisotropic Gaussian Processes with Non-stationary Increments

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 114-132页

作者： Jun WANG Zhen-long chen Wei-jie YUAN guang-jun SHEN School of Mathematics and Physics Anhui Polytechnic UniversityWuhu 241000China School of Statistics and Mathematics Zhejiang Gongshang UniversityHangzhou 310018China Department of Mathematics Anhui Normal UniversityWuhu 241000China

Let X={X(t),t∈R+} be a centered space anisotropic Gaussian process values in R^(d) with non-stationary increments,whose components are independent but may not be identically *** certain conditions,then almost surely c_(1)≤ϕ-m(X([0,1]))≤c_(2),where ϕ denotes the exact Hausdorff measure associated with function ϕ(s)=s1/α_(k)+Σ_(i=1)k(1-αi/αk)log log 1/s for some 1≤k≤d,(α_(1),…,α_(d))∈(0,1]^(d).We also obtain the exact Hausdorff measure of the graph of X on[0,1].

关键词： Hausdorff measure self-similar Gaussian processes non-stationary increment Lamperti theorem

Unintentional emissions of polychlorinated naphthalenes in China:Sources,composition,and historical trends

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Journal of Environmental Sciences 2025年第2期148卷 221-229页

作者： ye Huang Lin Huang Ying Li Nazupar Sidikjan Yunshan Zhang Yan chen Yangmin chen ye Li Wei Du Long chen YanWu Shanshan Zhang Jing Yang Wenjun Meng Guofeng Shen Min Liu Shu Tao Key Laboratory of Geographic Information Science of the Ministry of Education School of Geographic SciencesEast China Normal UniversityShanghai 200241China Yunnan Provincial Key Laboratory of Soil Carbon Sequestration and Pollution Control Faculty of Environmental Science&EngineeringKunming University of Science&TechnologyKunming 650500China Laboratory of Earth Surface Processes College of Urban and Environmental SciencePeking UniversityBeijing 100871China

Polychlorinated naphthalenes(PCNs)are detrimental to human health and the *** the commercial production of PCNs banned,unintentional releases have emerged as a significant environmental ***,relevant information is still *** this study,provincial emissions for eight PCNs homologues from 37 sources in the Chinese mainland during the period of 1960-2019 were estimated based on a source-specific and time-varying emission factor *** results showed that the total PCNs emissions in 2019 reached 757.0 kg with Hebei ranked at the top among all the provinces and iron&steel industry as the biggest ***-chlorinated PCNs comprised 90%of emissions by mass,while highly chlorinated PCNs dominated in terms of toxicity,highlighting divergent priorities for mitigating emissions and safeguarding human *** emissions showed an overall upward trend from 1960 to 2019 driven by emission increase from iron&steel industry in terms of source,and from North China and East China in terms of geographic ***-capita emissions followed an inverted U-shaped environmental Kuznets curvewhile emission intensities decreased with increasing per-capita Gross Domestic Product(GDP)following a nearly linear pattern when log-transformed.

关键词： PCNs Emission inventory Emission factor Composition profile Emission intensity Chinese mainland

Netrin-1 signaling pathway mechanisms in neurodegenerative diseases

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Neural Regeneration Research 2025年第4期20卷 960-972页

作者： Kedong Zhu Hualong Wang Keqiang ye Guiqin chen Zhaohui Zhang Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina Department of Neurology The First Hospital of Hebei Medical UniversityBrain Aging and Cognitive Neuroscience Laboratory of Heibei ProvinceShijiazhuangHebei ProvinceChina Faculty of Life and Health Sciences Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina

Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal *** profound impacts then extend into adulthood to encompass the maintenance of neuronal survival and synaptic *** amounts of evidence highlight several key points:(1)Diminished Netrin-1 levels exacerbate pathological progression in animal models of Alzheimer’s disease and Parkinson’s disease,and potentially,similar alterations occur in humans.(2)Genetic mutations of Netrin-1 receptors increase an individuals’susceptibility to neurodegenerative disorders.(3)Therapeutic approaches targeting Netrin-1 and its receptors offer the benefits of enhancing memory and motor function.(4)Netrin-1 and its receptors show genetic and epigenetic alterations in a variety of *** findings provide compelling evidence that Netrin-1 and its receptors are crucial targets in neurodegenerative *** a comprehensive review of Netrin-1 signaling pathways,our objective is to uncover potential therapeutic avenues for neurodegenerative disorders.

关键词： Alzheimer’s disease axon guidance colorectal cancer Netrin-1 receptors Netrin-1 signaling pathways Netrin-1 neurodegenerative diseases neuron survival Parkinson’s disease UNC5C

Interfacial electron rearrangement of 3D Fe_(3)O_(4)/h-YFeO_(3)composites for efficient electromagnetic wave absorption

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International Journal of Minerals,Metallurgy and Materials 2025年第3期32卷 609-618页

作者： Yi Sui Yingde Zhang guang Liu Lei Ji Junyu Yue chen Wu Mi Yan School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030China Key Laboratory of Rare Earths Chinese Academy of SciencesGanzhou 341119China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030032China

Interface modulation is an important pathway for highly efficient electromagnetic wave ***,tailored interfaces between Fe_(3)O_(4)particles and the hexagonal-YFeO_(3)(h-YFeO_(3))framework were constructed via facile *** resulting interfa-cial electron rearrangement at the heterojunction led to enhanced dielectric and magnetic loss *** results and density function theory(DFT)simulations demonstrate a transition in electrical properties from a half-metallic monophase to metallic Fe_(3)O_(4)/h-YFeO_(3)composites,emphasizing the advantages of the formed *** transformation of electron behavior is also accompan-ied by a redistribution of electrons at the Fe_(3)O_(4)/h-YFeO_(3)heterojunction,leading to the accumulation of localized electrons around the Y-O-Fe band bridge,consequently enhancing the polarization.A minimum reflection loss of-34.0 dB can be achieved at 12.0 GHz and 2.0 mm thickness with an effective bandwidth of 3.3 GHz due to the abundant interfaces,enhanced polarization,and rational ***,the synergistic effects endow the Fe_(3)O_(4)/h-YFeO_(3)composites with high performance and tunable functional properties for efficient electromagnetic absorption.

关键词： self-assembling heterojunction electron rearrangement interface modulation electromagnetic wave absorption