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Epigenetic and transcriptional landscapes during cerebral cortex development in a microcephaly mouse model

Journal of Genetics and Genomics 2024年第4期51卷 419-432页

作者： Qing Yang Qiang Cao Yue Yu Xianxin Lai Jiahao Feng Xinjie Li Yinan Jiang yazhou sun Zhong-Wei Zhou Xin Li School of Medicine Shenzhen Campus of Sun Yat-sen UniversityShenzhenGuangdong 518107China Academy of Medical Engineering and Translational Medicine Tianjin UniversityTianjin 300072China Scientific Research Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhenGuangdong 518107China Guangdong Provincial Key Laboratory of Digestive Cancer Research The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhenGuangdong 518107China

The cerebral cortex is a pivotal structure integral to advanced brain functions within the mammalian central nervous system.DNA methylation and hydroxymethylation play important roles in regulating cerebral cortex development.However,it remains unclear whether abnormal cerebral cortex development,such as microcephaly,could rescale the epigenetic landscape,potentially contributing to dysregulated gene expression during brain development.In this study,we characterize and compare the DNA methylome/hydroxymethylome and transcriptome profiles of the cerebral cortex across several developmental stages in wild-type(WT)mice and Mcph1 knockout(Mcph1-del)mice with severe microcephaly.Intriguingly,we discover a global reduction of 5′-hydroxymethylcytosine(5hmC)level,primarily in TET1-binding regions,in Mcph1-del mice compared to WT mice during juvenile and adult stages.Notably,genes exhibiting diminished 5hmC levels and concurrently decreased expression are essential for neurodevelopment and brain functions.Additionally,genes displaying a delayed accumulation of 5hmC in Mcph1-del mice are significantly associated with the establishment and maintenance of the nervous system during the adult stage.These findings reveal that aberrant cerebral cortex development in the early stages profoundly alters the epigenetic regulation program,which provides unique insights into the molecular mechanisms underpinning diseases related to cerebral cortex development.

关键词： Microcephaly Epigeneticmodification Tet1 Cerebral cortexdevelopment DNA hydroxymethylome Transcriptome

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Experimental and modeling study of surface topography generation considering tool-workpiece vibration in high-precision turning

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Chinese Journal of Aeronautics 2023年第7期36卷 194-212页

作者： Xingying ZHOU Henan LIU Tianyu YU Ruiyang GUO Guangzhou WANG yazhou sun Mingjun CHEN State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China

High-precision turning(HPT)is a main processing method for manufacturing rotary high-precision components,especially for metallic parts.However,the generated vibration between tool tip and workpiece during turning may seriously deteriorate the surface integrity.Therefore,exploring the effect of vibration on turning surface morphology and quality of copper parts using 3D surface topography regeneration model is crucial for predicting HPT performance.This developed model can update the machined surface topology in real time.In this study,the effects of tool arc radius,feed rate,radial vibration,axial vibration and tangential vibration on the surface topography and surface roughness were explored.The results show that the effect of radial vibration on surface topography is greater than that of axial vibration and tangential vibration.The radial vibration frequency is also critical.When vibration frequency changes,the surface topography profile presents three different types:the standard sinusoidal curve,the sinusoidal curve whose lowfrequency signal envelopes high-frequency signal,and the oscillation curve whose low-frequency signal superimposes high-frequency signal.In addition,HPT experiment was carried out to validate the developed model.The surface roughness obtained in the experiment was Ra=53 nm,while the roughness obtained by the simulation was Ra=46 nm,achieving a prediction accuracy of 86.7%.Received 4 September 2022;revised 3 October 2022;accepted 17 October 2022.

关键词： High-precision turning Machining vibration Modeling Surface roughness Surface topography

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Bacterial diacetyl suppresses abiotic stress-induced senescence in Arabidopsis

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Journal of Integrative Plant Biology 2022年第6期64卷 1135-1139页

作者： sunil K.Singh yazhou sun Yu Yang Ziwei Zuo Xiaoxuan Wu Chuyang Shao Li Peng Paul W.Paré Huiming Zhang Shanghai Center for Plant Stress Biology Center for Excellence in Molecular Plant Sciencesthe Chinese Academy of SciencesShanghai 201602China University of Chinese Academy of Sciences Beijing 100049China Department of Chemistry and Biochemistry Texas Tech UniversityLubbock 79409TexasUSA

Premature plant senescence induced by abiotic stresses is a major cause of agricultural losses worldwide. Tools for suppressing stress-induced plant senescence are limited. Here, we report that diacetyl, a natural compound emitted by the plantbeneficial bacterium Bacillus amyloliquefaciens,suppresses abscisic acid-mediated foliar senescence in Arabidopsis thaliana under various abiotic stress conditions. Our results establish diacetyl as an effective protector against stressinduced plant senescence and reveal a molecular mechanism for bacteria-enhanced plant stress resistance.

关键词： ABA diacetyl microbial volatile leaf senescence

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3D printing of tissue engineering scaffolds:a focus on vascular regeneration

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Bio-Design and Manufacturing 2021年第2期4卷 344-378页

作者： Pengju Wang yazhou sun Xiaoquan Shi Huixing Shen Haohao Ning Haitao Liu Department of Mechanical Manufacturing and Automation School of Mechatronics EngineeringHarbin Institute of TechnologyHarbin 150001China

Tissue engineering is an emerging means for resolving the problems of tissue repair and organ replacement in regenerative medicine.Insufficient supply of nutrients and oxygen to cells in large-scale tissues has led to the demand to prepare blood vessels.Scaffold-based tissue engineering approaches are effective methods to form new blood vessel tissues.The demand for blood vessels prompts systematic research on fabrication strategies of vascular scaffolds for tissue engineering.Recent advances in 3D printing have facilitated fabrication of vascular scaffolds,contributing to broad prospects for tissue vascularization.This review presents state of the art on modeling methods,print materials and preparation processes for fabrication of vascular scaffolds,and discusses the advantages and application fields of each method.Specially,significance and importance of scaffold-based tissue engineering for vascular regeneration are emphasized.Print materials and preparation processes are discussed in detail.And a focus is placed on preparation processes based on 3D printing technologies and traditional manufacturing technologies including casting,electrospinning,and Lego-like construction.And related studies are exemplified.Transformation of vascular scaffolds to clinical application is discussed.Also,four trends of 3D printing of tissue engineering vascular scaffolds are presented,including machine learning,near-infrared photopolymerization,4D printing,and combination of self-assembly and 3D printing-based methods.

关键词： Tissue engineering 3D printing Vascular scaffolds Print materials Modeling methods

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Micro Model of Carbon Fiber/Cyanate Ester Composites and Analysis of Machining Damage Mechanism

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Chinese Journal of Mechanical Engineering 2019年第3期32卷 198-208页

作者： Haitao Liu Jie Lin yazhou sun Jinyang Zhang Center for Precision Engineering School of Mechanical EngineeringHarbin Institute of TechnologyHarbin 150001China Rainbow Drone Technology Co. LtdChina Academy of Aerospace AerodynamicsBeijing 100000China

Machining damage occurs on the surface of carbon fiber reinforced polymer (CFRP) composites during processing. In the current simulation model of CFRP, the initial defects on the carbon fiber and the periodic random distribution of the reinforcement phase in the matrix are not considered in detail, which makes the characteristics of the cutting model significantly different from the actual processing conditions. In this paper, a novel three-phase model of carbon fiber/cyanate ester composites is proposed to simulate the machining damage of the composites. The periodic random distribution of the carbon fiber reinforced phase in the matrix was realized using a double perturbation algorithm. To achieve the stochastic distribution of the strength of a single carbon fiber, a novel method that combines the Weibull intensity distribution theory with the Monte Carlo method is presented. The mechanical properties of the cyanate matrix were characterized by fitting the stress-strain curves, and the cohesive zone model was employed to simulate the interface. Based on the model, the machining damage mechanism of the composites was revealed using finite element simulations and by conducting a theoretical analysis. Furthermore, the milling surfaces of the composites were observed using a scanning electron microscope, to verify the accuracy of the simulation results. In this study, the simulations and theoretical analysis of the carbon fiber/cyanate ester composite processing were carried out based on a novel three-phase model, which revealed the material failure and machining damage mechanism more accurately.

关键词： Carbon fiber reinforced polymer composites Micro simulation model Machining damage mechanism Milling and observation experiment Theoretical analysis

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Fabrication of Periodic Nanostructures Using AFM Tip-Based Nanomachining:Combining Groove and Material Pile-Up Topographies

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Engineering 2018年第6期4卷 787-795页

作者： Yanquan Geng Yongda Yan Jiqiang Wang Emmanuel Brousseau Yanwen sun yazhou sun Key Laboratory of Micro-systems and Micro-structures Manufacturing of the Ministry of Education Harbin Institute of TechnologyHarbin 150001China Center for Precision Engineering Harbin Institute of TechnologyHarbin 150001China Cardiff School of Engineering Cardiff UniversityCardiff CF24 3AAUK

This paper presents an atomic force microscopy(AFM)tip-based nanomachining method to fabricate periodic nanostructures.This method relies on combining the topography generated by machined grooves with the topography resulting from accumulated pile-up material on the side of these grooves.It is shown that controlling the distance between adjacent and parallel grooves is the key factor in ensuring the quality of the resulting nanostructures.The presented experimental data show that periodic patterns with good quality can be achieved when the feed value between adjacent scratching paths is equal to the width between the two peaks of material pile-up on the sides of a single groove.The quality of the periodicity of the obtained nanostructures is evaluated by applying one-and two-dimensional fast Fourier transform(FFT)algorithms.The ratio of the area of the peak part to the total area in the normalized amplitude–frequency characteristic diagram of the cross-section of the measured AFM image is employed to quantitatively analyze the periodic nanostructures.Finally,the optical effect induced by the use of machined periodic nanostructures for surface colorization is investigated for potential applications in the fields of anti-counterfeiting and metal sensing.

关键词： Atomic force microscopy Nanomachining Periodic nanostructure Single-crystal copper

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Bioscaffolds embedded with regulatory modules for cell growth and tissue formation:A review

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Bioactive Materials 2021年第5期6卷 1283-1307页

The demand for artificial organs has greatly increased because of various aging-associated diseases and the wide need for organ transplants.A recent trend in tissue engineering is the precise reconstruction of tissues by the growth of cells adhering to bioscaffolds,which are three-dimensional(3D)structures that guide tissue and organ formation.Bioscaffolds used to fabricate bionic tissues should be able to not only guide cell growth but also regulate cell behaviors.Common regulation methods include biophysical and biochemical stimulations.Biophysical stimulation cues include matrix hardness,external stress and strain,surface topology,and electromagnetic field and concentration,whereas biochemical stimulation cues include growth factors,proteins,kinases,and magnetic nanoparticles.This review discusses bioink preparation,3D bioprinting(including extrusion-based,inkjet,and ultraviolet-assisted 3D bioprinting),and regulation of cell behaviors.In particular,it provides an overview of state-of-the-art methods and devices for regulating cell growth and tissue formation and the effects of biophysical and biochemical stimulations on cell behaviors.In addition,the fabrication of bioscaffolds embedded with regulatory modules for biomimetic tissue preparation is explained.Finally,challenges in cell growth regulation and future research directions are presented.

关键词： 3D bioprinting Bioscaffolds Cell growth regulation Organ reconstruction Synergetic stimulation

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二氧化碳电催化还原酸性体系研究进展

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材料导报 2024年第8期38卷 51-56页

作者：孙亚洲徐沙邹金含吴智华谢顺吉厦门大学化学化工学院固体表面物理化学国家重点实验室能源材料化学协同创新中心福建能源材料科学与技术创新实验室福建厦门361005

利用可再生能源提供的电能电催化还原CO_(2)制高值化学品和燃料,为全球气候变暖和能源危机提供了一种可行的解决方案,具有巨大的实际应用潜力。目前研究较多的碱性和中性反应体系中CO_(2)易与氢氧根(OH^(-))反应生成碳酸盐或碳酸氢盐,造... 详细信息

利用可再生能源提供的电能电催化还原CO_(2)制高值化学品和燃料,为全球气候变暖和能源危机提供了一种可行的解决方案,具有巨大的实际应用潜力。目前研究较多的碱性和中性反应体系中CO_(2)易与氢氧根(OH^(-))反应生成碳酸盐或碳酸氢盐,造成CO_(2)损失的同时会降低反应体系的能量转化效率和稳定性。研究开发酸性体系的电催化还原CO_(2)反应(CO_(2)RR),有望解决上述问题。本文针对CO_(2)电催化还原的酸性体系展开讨论,系统整理了反应装置、催化剂、反应微环境对CO_(2)RR性能的影响以及酸性体系中的微观反应机理,最后针对酸性体系中催化剂设计、反应机理研究、反应微环境调控、反应器设计优化等提出前瞻性建议。

关键词：二氧化碳电催化还原酸性电解体系

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Field-scale spatial variability of soil calcium in a semi-arid region:Implications for soil erosion and site-specific management

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Pedosphere 2021年第5期31卷 705-714页

作者： yazhou sun Wenxuan GUO David CWEINDORF Fujun sun Sanjit DEB Guofeng CAO Jasmine NEUPANE Zhe LIN Abir RAIHAN Department of Plant and Soil Science Texas Tech UniversityLubbock TX 79409(USA) Department of Soil and Crop Sciences Texas A&M AgriLife ResearchLubbock TX 79403(USA) Department of Earth and Atmospheric Sciences Central Michigan UniversityMount Pleasant MI 48859(USA) College of Land and Environment Shenyang Agricultural UniversityShenyang 110866(China) Department of Geography University of ColoradoBoulder CO 80309(USA)

Excess calcium(Ca)in soils of semi-arid and arid regions has negative effects on soil structure and chemical properties,which limits the crop root growth as well as the availability of soil water and nutrients.Quantifying the spatial variability of soil Ca contents may reveal factors influencing soil erosion and provide a basis for site-specific soil and crop management in semi-arid regions.This study sought to assess the spatial variability of soil Ca in relation to topography,hydraulic attributes,and soil types for precision soil and crop management in a 194-ha production field in the Southern High Plains of Texas,USA.Soils at four depth increments(0-2,0-15,15-30,and 30-60 cm)were sampled at 232 points in the spring of 2017.The Ca content of each sample was determined with a DP-6000 Delta Premium portable X-ray fluorescence(PXRF)spectrometer.Elevation data was obtained using a real-time kinematic GPS receiver with centimeter-level accuracy.A digital elevation model(DEM)was derived from the elevation data,and topographic and hydraulic attributes were generated from this DEM.A generalized least-squares model was then developed to assess the relationship between soil Ca contents of the four layers and the topographic and hydraulic attributes.Results showed that topographic attributes,especially slope and elevation,had a significant effect on soil Ca content at different depths(P<0.01).In addition,hydraulic attributes,especially flow length and sediment transport index(STI),had a significant effect on the spatial distribution of soil Ca.Spatial variability of soil Ca and its relationships with topographic and hydraulic attributes and soil types indicated that surface soil loss may occur due to water or wind erosion,especially on susceptible soils with high slopes.Therefore,this study suggests that the application of PXRF in assessing soil Ca content can potentially facilitate a new method for soil erosion evaluation in semi-arid lands.The results of this study provide valuable information for site-specific soil con

关键词： hydraulic attributes portable X-ray fluorescence spectrometry precision agriculture soil conservation topography

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类ChatGPT赋能指挥控制的情报提升和情报局限--基于信息流动模型

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情报杂志 2024年第6期43卷 117-125页

作者：孙亚洲李晓松吕彬杨慧军事科学院军事科学信息研究中心北京100142

[研究目的]研究类ChatGPT赋能指挥控制的情报提升和情报局限,探索未来战争的情报作用发挥机理。[研究方法]引入指挥控制活动的基本范式PREA-OODA循环,提出情报学视角下的信息流动模型,基于该模型分析类ChatGPT应用于指挥控制的情报提升... 详细信息

[研究目的]研究类ChatGPT赋能指挥控制的情报提升和情报局限,探索未来战争的情报作用发挥机理。[研究方法]引入指挥控制活动的基本范式PREA-OODA循环,提出情报学视角下的信息流动模型,基于该模型分析类ChatGPT应用于指挥控制的情报提升和情报局限。[研究结论]类ChatGPT对指挥控制的情报赋能原理为:优化态势生成过程和辅助决策过程,获得更佳的信息状态或结果。类ChatGPT技术应用于指挥控制系统能带来巨大的情报能力提升,也可能因其情报局限引发灾难性后果。从情报赋能原理和阶段的角度探索类ChatGPT在指挥控制中的应用。

关键词：生成式人工智能辅助决策情报赋能情报局限 ChatGPT 指挥控制

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