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Microstructure evolution and mechanical properties at high temperature of selective laser melted Alsi10Mg

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Journal of Materials science & Technology 2021年第3期62卷 162-172页

作者： Y.Cao X.Lin q.Z.Wang s.q.shi L.Ma N.Kang W.D.Huang state Key Laboratory of solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi’an 710072China

In this study,the microstructure and tensile properties of selective laser melted AlsilOMg at elevated temperature were investigated with focus on the interfacial region.In-situ sEM and in-situ EBsD analysis were proposed to characterize the microstructural evolution with temperature.The as-fabricated AlsilOMg sample presents high tensile strength with the ultimate tensile strength(UTs)of~450 MPa and yield strength(Ys)of~300 MPa,which results from the mixed strengthening mechanism among grain boundary,solid solution,dislocation and Orowan looping mechanism.When holding at the temperature below 200℃for 30 min,the micro structure presents little change,and only a slight decrement of yield strength appears due to the relief of the residual stress.However,when the holding temperature further increases to 300℃and 400℃,the coarsening and precipitation of si particles inα-Al matrix occur obviously,which leads to an obvious decrease of solid solution strength.At the same time,matrix softening and the weakness of dislocation strengthening also play important roles.When the holding temperature reaches to 400℃,the yield strength decreases significantly to about 25 MPa which is very similar to the as-cast Al alloy.This might be concluded that the Ys is dominated by the matrix materials.Because the softening mechanism counteracts work hardening,the extremely high elongation occurs.

关键词： selective laser melting Alsi10Mg Microstructure In-situ EBsD High temperature tensile property

seismic and geological evidence of hidden faults in the Yinpan Reservoir area based on a dense seismic array

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science China Earth sciences 2024年第7期67卷 2401-2407页

作者： Guangyao YIN Huai ZHANG Liwen GONG q ipeng BAI Yicun GUO Bing ZHANG Yaolin shi Key Laboratoryof Earth system Numerical Modeling and Application(Chinese Academyof sciences) College of Earth and Planetary SciencesUniversity of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Computational Geodynamics Chinese Academy of SeiencesBeijing 100049China southern Marine science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China Beijing Yanshan Critical Zone National Field scientific Observation and Research station Beijing 101408China Chongging Earthquake Agency Chongqing 401147 China Institute of Earthquake Forecasting China Earthquake AdministrationBeijing 100036China Hangzhou Applied Acoustics Research Institute Hangzhou 311100China siaie Key Laboratory of Geodesy and Earths Dynamics Innovation Academy for Precision Measurement Science and TechnologyCASWuhan 430077China

1.Introduction.On November 23,2017,an M_(s)5.0 earthquake occurred in Wulong,Chongqing,China,resulting in tens of casualties and considerable economic loss.Geologically,the epicenter of this earthquake was located in the transition zone from the Central Chongqing Fold Belt to the southeast,characterized by a low tectonic loading rate.

关键词： earthquake southeast seismic

Mechanical Behavior of Bamboo,and Its Biomimetic Composites and structural Members:A systematic Review

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Journal of Bionic Engineering 2024年第1期21卷 56-73页

作者： shanyu Han Yuyuan He Hanzhou Ye Xueyong Ren Fuming Chen Kewei Liu sheldon q.shi Ge Wang Institute of Biomaterials for Bamboo and Rattan Resources International Centre for Bamboo and RattanBeijing 100102China Key Laboratory of National Forestry and Grassland Administration/Beijing for Bamboo&Rattan science and Technology Beijing 100102China National Forestry and Grassland Engineering Technology Center for Wood Resources Recycling College of Materials Science and TechnologyBeijing Forestry UniversityBeijing 100083China International Bamboo and Rattan Organization Beijing 100102China school of Civil Engineering Tsinghua UniversityBeijing 100084China Mechanical Engineering Department University of North TexasDentonTX 762077102USA

Bamboo is a typical biological material widely growing in nature with excellent physical and mechanical properties.It is lightweight with high strength and toughness.The naturally optimized bamboo structure,which has inspired global material scientists and engineers for decades,is significantly important for the bionic design of novel structural materials with ultra-light,ultra-strong,or ultra-tough and comprehensive properties.Typical literature on innovative composite materials and structural members inspired by bamboo are reviewed in this paper,and the research progress and prospects in this field are expounded in three parts.First,the structural characteristics of the bamboo wall layer along the thickness and height directions are described in terms of chemical composition,gradient structure,pore structure,and hollow structure with variable cross-section.second,this paper summarizes the research progress on new composite materials and structural components by applying bamboo’s structural features from the perspective of sustainability,designability,and customization.Finally,given the limitations of current research,the biomimetic scientific research on bamboo’s structural characteristics is prospected from the interpretation of bamboo structure,new bamboo-like materials,and structural design optimization perspectives,providing a reference for future research on biomimetic aspects of biomass.

关键词： Bamboo structural characteristics-Bamboo-like material Physical and mechanical properties

严重肝病表型的肝豆状核变性患者的临床与遗传特征分析

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中华肝脏病杂志 2024年第6期32卷 551-557页

作者： q q Xiao Y H Xu X Xu Y W shi H X Cao X q Liu J G Fan Department of Gastroenterology Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine Shanghai 200092 China. Department of Pediatric Endocrinology and Genetic Metabolism Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine Shanghai 200092 China.

目的:探讨肝豆状核变性(HLD)患者严重肝病表型的临床和遗传特征及其预测模型。方法:以1989年1月至2022年12月在上海交通大学医学院附属新华医院确诊的HLD住院患者为研究对象,根据受累器官进行临床分型,将有肝病表型者归于肝病组并进一... 详细信息

目的:探讨肝豆状核变性(HLD)患者严重肝病表型的临床和遗传特征及其预测模型。方法:以1989年1月至2022年12月在上海交通大学医学院附属新华医院确诊的HLD住院患者为研究对象,根据受累器官进行临床分型,将有肝病表型者归于肝病组并进一步分为严重肝病组和普通肝病组。比较各组患者临床特征及基因变异,多元回归分析严重肝病患者的预测指标。据资料不同采用t检验、Mann-Whitney U检验或χ2检验进行统计学分析。结果:159例HLD患者中肝病组142例(其中严重肝病组34例,普通肝病组108例),脑病组17例,肝病组和脑病组发病的中位数年龄差异有统计学意义[12.6(7.0,13.3)岁对16.9(11.0,21.5)岁,Pstic回归分析显示严重肝病的预测因素为p.Arg778Leu纯合突变、总胆红素、胆汁酸(OR分别为16.512、1.022、1.021,95%CI分别为1.204~226.425、1.005~1.039、1.006~1.037,P值均<0.05),绘制受试者操作特征曲线的界值为0.2153,曲线下面积为0.9532,灵敏度为90.91%,特异度为92.42%。结论:HLD患者肝病表型常见且起病早,总胆红素、胆汁酸、ATP7B基因的p.Arg778Leu纯合突变与HLD患者肝病严重程度相关,有助于预测严重肝病发生风险。

关键词：肝豆状核变性肝衰竭预测因素基因突变列线图诊断

Physiological and pathological functions of circular RNAs in the nervous system

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Neural Regeneration Research 2024年第2期19卷 342-349页

作者： Min Zhou shi Li Chuan Huang school of Life sciences Chongqing UniversityChongqingChina

Circular RNAs(circRNAs)are a class of covalently closed single-stranded RNAs that are expressed during the development of specific cells and tissues.CircRNAs play crucial roles in physiological and pathological processes by sponging microRNAs,modulating gene transcription,controlling the activity of certain RNA-binding proteins,and producing functional peptides.A key focus of research at present is the functionality of circRNAs in the nervous system and several advances have emerged over the last 2 years.However,the precise role of circRNAs in the nervous system has yet to be comprehensively reviewed.In this review,we first summarize the recently described roles of circRNAs in brain development,maturity,and aging.Then,we focus on the involvement of circRNAs in various diseases of the central nervous system,such as brain cancer,chronic neurodegenerative diseases,acute injuries of the nervous system,and neuropathic pain.A better understanding of the functionality of circRNAs will help us to develop potential diagnostic,prognostic,and therapeutic strategies to treat diseases of the nervous system.

关键词： Alzheimer’s disease amyotrophic lateral sclerosis brain development circRNAs neuropathic pain Parkinson’s disease

Induced pluripotent stem cells(iPsCs):molecular mechanisms of induction and applications

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signal Transduction and Targeted Therapy 2024年第5期9卷 2065-2090页

作者： Jonas Cerneckis Hongxia Cai Yanhong shi Department of Neurodegenerative Diseases Beckman Research Institute of City of HopeDuarteCA 91010USA Irell&Manella Graduate school of Biological sciences Beckman Research Institute of City of HopeDuarteCA 91010USA

The induced pluripotent stem cell(iPsC)technology has transformed in vitro research and holds great promise to advance regenerative medicine.iPsCs have the capacity for an almost unlimited expansion,are amenable to genetic engineering,and can be differentiated into most somatic cell types.iPsCs have been widely applied to model human development and diseases,perform drug screening,and develop cell therapies.In this review,we outline key developments in the iPsC field and highlight the immense versatility of the iPsC technology for in vitro modeling and therapeutic applications.We begin by discussing the pivotal discoveries that revealed the potential of a somatic cell nucleus for reprogramming and led to successful generation of iPsCs.We consider the molecular mechanisms and dynamics of somatic cell reprogramming as well as the numerous methods available to induce pluripotency.subsequently,we discuss various iPsC-based cellular models,from mono-cultures of a single cell type to complex three-dimensional organoids,and how these models can be applied to elucidate the mechanisms of human development and diseases.We use examples of neurological disorders,coronavirus disease 2019(COVID-19),and cancer to highlight the diversity of disease-specific phenotypes that can be modeled using iPsC-derived cells.We also consider how iPsC-derived cellular models can be used in high-throughput drug screening and drug toxicity studies.Finally,we discuss the process of developing autologous and allogeneic iPsC-based cell therapies and their potential to alleviate human diseases.

关键词： mechanisms programming holds

Weakly Compact sets and Riesz Representation Theorem in Musielak sequence spaces

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Acta Mathematica sinica,English series 2024年第2期40卷 467-484页

作者： Wan Zhong GONG si Yu shi Zhong Rui shi Department of Mathematics Anhui Normal UniversityWuhu 241000P.R.China smeal College of Business Pennsylvania State UniversityUniversity ParkPennsylwania 16802USA Department of Mathematics Shanghai UniversityShanghai 200444P.R.China

In this work,we give some criteria of the weakly compact sets and a representation theorem of Riesz's type in Musielak sequence spaces using the ideas and techniques of sequence spaces and Musielak function.Finally,as an immediate consequence of the criteria considered in this paper,the criteria of the weakly compact sets of Orlicz sequence spaces are deduced.

关键词： Compact set weak topology Banach space dual space Musielak sequence spaces

UNIFORM sUPERCONVERGENCE ANALYsIs OF A TWO-GRID MIXED FINITE ELEMENT METHOD FOR THE TIME-DEPENDENT BI-WAVE PROBLEM MODELING D-WAVE sUPERCONDUCTORs

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Journal of Computational Mathematics 2024年第2期42卷 415-431页

作者： Yanmi Wu Dongyang shi PLA Information Engineering University Zhengzhou 450001China school of Mathematics and Information sciences Yantai UniversityYantai 264005China

In this paper,a two-grid mixed finite element method(MFEM)of implicit Backward Euler(BE)formula is presented for the fourth order time-dependent singularly perturbed Bi-wave problem for d-wave superconductors by the nonconforming Eq_(1)^(rot) element.In this approach,the original nonlinear system is solved on the coarse mesh through the Newton iteration method,and then the linear system is computed on the fine mesh with Taylor’s expansion.Based on the high accuracy results of the chosen element,the uniform superclose and superconvergent estimates in the broken H^(1)-norm are derived,which are independent of the negative powers of the perturbation parameter appeared in the considered problem.Numerical results illustrate that the computing cost of the proposed two-grid method is much less than that of the conventional Galerkin MFEM without loss of accuracy.

关键词： Time-dependent Bi-wave problem Two-grid mixed finite element method Uniform superclose and superconvergent estimates

Clinical features and prognostic factors of duodenal neuroendocrine tumours:A comparative study of ampullary and nonampullary regions

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 907-918页

作者： sa Fang Yu-Peng shi Lu Wang shuang Han Yong-quan shi Department of Gastroenterology Honghui HospitalXi’an Jiaotong UniversityXi'an 710054Shanxi ProvinceChina Department of Gastroenterology The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710032Shaanxi ProvinceChina Department of Gastroenterology Xijing Hospital Affiliated to Air Force Medical UniversityXi'an 710032Shaanxi ProvinceChina

BACKGROUND Duodenal neuroendocrine tumours(DNETs)are rare neoplasms.However,the incidence of DNETs has been increasing in recent years,especially as an incidental finding during endoscopic studies.Regrettably,there is no consensus regarding the ideal treatment of DNETs.Even there are few studies on the clinical features and survival analysis of DNETs.AIM To analyze the clinical characteristics and prognostic factors of patients with duodenal neuroendocrine tumours.METHODs The clinical data of DNETs diagnosed in the First Affiliated Hospital of Air Force Military Medical University from June 2011 to July 2022 were collected.Neuroen-docrine tumours located in the ampulla area of the duodenum were divided into the ampullary region group;neuroendocrine tumours in any part of the duo-denum outside the ampullary area were divided into the nonampullary region group.Using a retrospective study,the clinical characteristics of the two groups and risk factors affecting the survival of DNET patients were analysed.REsULTs Twenty-nine DNET patients were screened.The male to female ratio was 1:1.9,and females comprised the majority.The ampullary region group accounted for 24.1%(7/29),while the nonampullary region group accounted for 75.9%(22/29).When diagnosed,the clinical symptoms of the ampullary region group were mainly abdominal pain(85.7%),while those of the nonampullary region groups were mainly abdominal distension(59.1%).There were differences in the composition of staging of tumours between the two groups(Fisher's exact probability method,P=0.001),with nonampullary stage II tumours(68.2%)being the main stage(Psis of DNETs,the survival rate of the ampullary region group was 14.3%(1/7),which was lower than that of 72.7%(16/22)in the nonampullary region group(Fisher's exact probability method,P=0.011).The survival time of the ampullary region group was shorter than that of the nonampullary region group(Psurvival time of the ampullary region group was 10.0 months and that of the no

关键词： Duodenum Neuroendocrine Tumour Ampullary Nonampullary Clinical features Prognostic