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单晶铜中的类层错四面体稳定性

固体力学学报 2020年第6期41卷 567-584页

作者：郁汶山张磊申胜平西安交通大学航天航空学院机械结构强度与振动国家重点实验室陕西省航天结构振动控制工程实验室西安710049

层错四面体作为受核辐照作用金属材料中一类常见的三维缺陷,会极大的改变材料塑性变形行为.论文借助分子静力学和分子动力学方法,针对不同构型、不同尺寸的类层错四面体,考察了不同形状空位团簇演化为类层错四面体的位错反应机理和形成... 详细信息

层错四面体作为受核辐照作用金属材料中一类常见的三维缺陷,会极大的改变材料塑性变形行为.论文借助分子静力学和分子动力学方法,针对不同构型、不同尺寸的类层错四面体,考察了不同形状空位团簇演化为类层错四面体的位错反应机理和形成能变化趋势,研究了类层错四面体附近空位形成能分布特征和最小空位形成能随类层错四面体尺寸增大的变化规律,分析了含不同构型、不同尺寸的类层错四面体铜单晶体的微观变形机理和单晶体屈服应力随类层错四面体尺寸增大的变化规律.研究发现:类层错四面体通过Silcox-Hirsch机制形成,且经历了空位团簇坍塌、Frank位错环分解和Shockley位错交汇形成层错四面体棱边三个过程;类层错四面体附近最小空位形成能随着类层错四面体尺寸变化而变化,且变化趋势与类层错四面体构型在稳态、亚稳态和非稳态之间过渡相关,稳态无尖端类层错四面体的最小空位形成能变化趋势表现出明显的尺寸效应;剪切会导致含类层错四面体铜单晶体产生两类层错四面体位错开动模式,即:斜面Shockley偏位错滑移和层错四面体底面压杆位错分解,且含类层错四面体的单晶体屈服应力基本上随着类层错四面体尺寸增大而逐渐减小.

关键词：位错类层错四面体空位稳定性

Single-cell brain atlas of Parkinson's disease mouse model

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Journal of Genetics and Genomics 2021年第4期48卷 277-288页

作者： Jixing Zhong Gen Tang Jiacheng Zhu Weiying Wu Ge Li Xiumei Lin Langchao Liang Chaochao Chai yuying Zeng Feiyue Wang Lihua Luo Jiankang Li Fang Chen Zhen Huang Xiuqing Zhang yu Zhang Hongde Liu Xin Qiu shengping Tang Dongsheng Chen School of Biological Science&Medical Engineering Southeast UniversityNanjing 210096China BGI-Shenzhen Shenzhen 518083China Shenzhen Children's Hospital Shenzhen 518083China BGI Education Center University of Chinese Academy of SciencesShenzhen 518083China Department of Neurobiology NHC and CAMS Key Laboratory of Medical NeurobiologySchool of Brain Science and Brian MedicineAnd the MOE Frontier Science Center for Brain Research and Brain-Machine IntegrationZhejiang University School of MedicineHangzhou 310012China Guangdong Provincial Key Laboratory of Laboratory Animals Guangdong Laboratory Animals Monitoring InstituteGuangzhouGuangdong 510663China MGI BGI-ShenzhenShenzhen 518083China Life Science College Fujian Normal UniversityFuzhou 350108China Key Laboratory of Special Marine Bio-resources Sustainable Utilization of Fujian Province Fuzhou 350108China

Parkinson's disease(PD)is a neurodegenerative disease,leading to the impairment of movement *** pathogenesis has been largely investigated,either limited to bulk transcriptomic levels or at certain cell types,which failed to capture the cellular heterogeneity and intrinsic interplays among distinct cell ***,we report the application of single-nucleus RNA-seq on midbrain,striatum,and cerebellum of theα-syn-A53 T mouse,a well-established PD mouse model,and matched controls,generating the first single cell transcriptomic atlas for the PD model mouse brain composed of 46,174 individual ***,we comprehensively depicte the dysfunctions in PD pathology,covering the elevation of NF-k B activity,the alteration of ion channel components,the perturbation of protein homeostasis network,and the dysregulation of glutamatergic ***,we identify a variety of cell types closely associated with PD risk *** together,our study provides valuable resources to systematically dissect the molecular mechanism of PD pathogenesis at the single-cell resolution,which facilitates the development of novel approaches for diagnosis and therapies against PD.

关键词： Parkinson’s disease α-syn-A53T Single-nucleus RNA-Seq Pathogenesis Neuroinflammtion

对陶瓷器件超声识别的算法设计及虚拟仪器实现

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振动与冲击 2022年第17期41卷 254-261页

作者：刘昱贺升平贺西平王杰周越陕西师范大学物理学与信息技术学院陕西省超声重点实验室西安710119 四川省泸州市116号信箱1分箱四川泸州646000

防止重要物品被伪造替换,提出了超声指纹识别算法并编制了识别程序。在此基础上,利用超声检测卡研制了一个对陶瓷器件进行超声防伪识别的虚拟仪器—工控机。该工控机可以多通道检测且检波方式多样,增益调节灵活,可同时完成信号的发射和... 详细信息

防止重要物品被伪造替换,提出了超声指纹识别算法并编制了识别程序。在此基础上,利用超声检测卡研制了一个对陶瓷器件进行超声防伪识别的虚拟仪器—工控机。该工控机可以多通道检测且检波方式多样,增益调节灵活,可同时完成信号的发射和接收。以工控机进行了多组试验测试,测试结果表明,该工控机对外形一致的陶瓷器件可以准确识别区分。随后,研究了对探头旋转、偏移、对探头施加不同压力和改变底衬等因素对识别结果的影响。通过对样品在不同形状、材料、压力和边界等条件下的测试,结果表明,该技术可以实现外表一致的陶瓷器件的有效识别。研制的工控机为实现超声防伪识别系统的智能化、自动化、一体化、小型化奠定了良好的基础。

关键词：超声检测虚拟仪器陶瓷器件散射信号超声指纹

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基于线性预测分析的金属材料超声识别方法

兵器装备工程学报 2023年第10期44卷 307-312,328页

作者：刘昱贺升平贺西平陕西师范大学物理学与信息技术学院陕西省超声重点实验室西安710119 泸州高新技术研究所四川泸州646000

针对金属材料中超声波的背向散射与其微观结构特征密切相关,即使材料相同,超声信号也会因金属晶粒的尺寸和径向分布的随机性而产生差异的问题。计算了金属样品超声信号的线性预测系数,以此作为其超声指纹,结合拉伊达判别准则确定的阈值... 详细信息

针对金属材料中超声波的背向散射与其微观结构特征密切相关,即使材料相同,超声信号也会因金属晶粒的尺寸和径向分布的随机性而产生差异的问题。计算了金属样品超声信号的线性预测系数,以此作为其超声指纹,结合拉伊达判别准则确定的阈值,完成了对形状、材料完全一致的金属样品的识别。结果表明:基于线性预测分析的超声金属材料识别方法可以快速、准确地识别出各样品。该方法对贵重金属材料、金属文物的识别保护具有一定的参考应用价值。

关键词：超声背向散射线性预测分析拉伊达法则超声指纹识别阈值

Surgical intervention combined with weight-bearing walking training promotes recovery in patients with chronic spinal cord injury:a randomized controlled study

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Neural Regeneration Research 2024年第12期19卷 2773-2784页

作者： Hui Zhu James D.Guest Sarah Dunlop Jia-Xin Xie Sujuan Gao Zhuojing Luo Joe E.Springer Wutian Wu Wise Young Wai Sang Poon Song Liu Hongkun Gao Tao yu Dianchun Wang Libing Zhou shengping Wu Lei Zhong Fang Niu Xiaomei Wang Yansheng Liu Kwok-Fai So Xiao-Ming Xu Kunming Tongren Hospital KunmingYunnan ProvinceChina Neurological Surgery and the Miami Project to Cure ParalysisMiller School of MedicineUniversity of MiamiMiamiFLUSA School of Biological Sciences The University of Western AustraliaPerthWAAustralia Minderoo Foundation PerthWAAustralia Clinical Center for Spinal Cord Injury Kunming General Hospital of Chengdu Military CommandKunmingYunnan ProvinceChina Department of Biostatistics and Health Data Science Indiana University School of MedicineIndianapolisINUSA Department of Orthopedic Spinal Surgery Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina Spinal Cord and Brain Injury Research Center Department of Physical Medicine and RehabilitationUniversity of Kentucky College of MedicineLexingtonKYUSA Guangdong-HongKong-Macao Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina W.M.Keck Center for Collaborative Neuroscience Rutgers UniversityPiscatawayNJUSA Neurosurgery Department Chinese University of Hong KongPrince of Wales HospitalHong Kong Special Administration RegionChina Spinal Cord and Brain Injury Research Group Stark Neurosciences Research InstituteDepartment of Neurological SurgeryIndiana University School of MedicineIndianapolisINUSA

For patients with chronic spinal cord injury,the co nventional treatment is rehabilitation and treatment of spinal cord injury complications such as urinary tract infection,pressure sores,osteoporosis,and deep vein *** is rarely perfo rmed on spinal co rd injury in the chronic phase,and few treatments have been proven effective in chronic spinal cord injury *** of effective therapies fo r chronic spinal co rd injury patients is *** conducted a randomized controlled clinical trial in patients with chronic complete thoracic spinal co rd injury to compare intensive rehabilitation(weight-bearing walking training)alone with surgical intervention plus intensive *** clinical trial was registered at ***(NCT02663310).The goal of surgical intervention was spinal cord detethering,restoration of cerebrospinal fluid flow,and elimination of residual spinal cord *** found that surgical intervention plus weight-bearing walking training was associated with a higher incidence of American Spinal Injury Association Impairment Scale improvement,reduced spasticity,and more rapid bowel and bladder functional recovery than weight-bearing walking training ***,the surgical procedures and intensive rehabilitation were *** Spinal Injury Association Impairment Scale improvement was more common in T7-T11 injuries than in T2-T6 *** combined with rehabilitation appears to have a role in treatment of chronic spinal cord injury patients.

关键词： chronic spinal cord injury intensive rehabilitation locomotor training neurological recovery surgical intervention weightbearing walking training

Thermo-optic phase shifters based on silicon-on-insulator platform: state-of-the-art and a review

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Frontiers of Optoelectronics 2022年第1期15卷 92-112页

作者： shengping Liu Junbo Feng Ye Tian Heng Zhao Li Jin Boling Ouyang Jiguang Zhu Jin Guo Chongqing United Microelectronics Center Chongqing 401332China

Silicon photonic platforms offer relevance to large markets in many applications,such as optical phased arrays,photonic neural networks,programmable photonic integrated circuits,and quantum computation *** one of the basic tuning devices,the thermo-optic phase shifter(TOPS)plays an important role in all these applications.A TOPS with the merits of easy fabrication,low power consumption,small thermal time constant,low insertion loss,small footprint,and low crosstalk,is needed to improve the performance and lower the cost of the above *** meet these demands,various TOPS have been proposed and experimentally demonstrated on different foundry platforms In this paper,we review the state-of-the-art of TOPS,including metal heater,doped silicon,silicide,with silicon substrate undercut for heat insulation,folded waveguide structure,and multi-pass waveguide *** further compare these TOPSs and propose the directions of the future developments on TOPS.

关键词： Thermo-optic phase shifter Photonic integrated circuits(PICs) Optical switches Silicon photonics

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可回收火箭动力着陆段在线制导算法

清华大学学报（自然科学版） 2021年第3期61卷 230-239页

作者：宋雨张伟苗新元张志国龚胜平清华大学航天航空学院北京100084 北京宇航系统工程研究所北京100076

针对火箭垂直回收精确着陆问题,该文研究了基于凸优化的在线制导算法,提出了一种制导、导航与控制一体化闭环数值仿真方法。通过无损凸化和逐次凸化方法,将火箭回收段制导问题转化为二阶锥优化问题,并结合内点法将该特定问题进行定制求... 详细信息

针对火箭垂直回收精确着陆问题,该文研究了基于凸优化的在线制导算法,提出了一种制导、导航与控制一体化闭环数值仿真方法。通过无损凸化和逐次凸化方法,将火箭回收段制导问题转化为二阶锥优化问题,并结合内点法将该特定问题进行定制求解。研究了在随机大气扰动、发动机节流特性、导航系统随机偏差以及系统整体时延等多重不确定因素作用下算法的鲁棒性。通过对问题进行定制化求解,该算法具备毫秒级的收敛特性,且具有较高的算法鲁棒性。在动力学环境扰动、控制和导航系统偏差以及系统整体延时等不同扰动的组合作用下,该算法的仿真结果满足火箭回收精确软着陆的要求。

关键词：可回收火箭精确软着陆在线制导凸优化闭环数值仿真

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基于模式间混淆关系自适应构建层次化分类器

信号处理 2006年第1期22卷 43-48页

作者：张静宋锐夏胜平郁文贤国防科学技术大学ATR重点实验室长沙410073

为了解决层次化分类器的设计难点——子分类器的层属关系及其内部组成的确定,本文首先定义了模式间混淆关系,用于描述不同模式在判决域中的相互作用;进而提出了基于混淆矩阵度量模式间混淆关系的方法。设计并实现了多模式混淆关系分析机... 详细信息

为了解决层次化分类器的设计难点——子分类器的层属关系及其内部组成的确定,本文首先定义了模式间混淆关系,用于描述不同模式在判决域中的相互作用;进而提出了基于混淆矩阵度量模式间混淆关系的方法。设计并实现了多模式混淆关系分析机MPCRAM,将有师指派和无师自组两种常用的模式重组方法有机结合,遵循Fisher准则,自适应地产生层次化分类器结构。大量综合测试证实了该方法有效、实用,可显著提高分类器的识别性能和稳健性。

关键词：模式识别混淆关系度量多模式混淆关系分析机层次化分类器自适应模式组合

Screening for musculoskeletal system malformations and birth injuries in newborns:Results of a screening program in two hospitals in Shenzen,China

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Pediatric Investigation 2022年第3期6卷 156-162页

作者： Zhu Xiong Zhenhui Zhao Hansheng Deng Xin Qiu Weiqing Li Xiaodi Chen yu Tang Shuai Han Jiaxin Zhao Ting Cai Xian Liu Shuaidan Zeng shengping Tang Department of Pediatric Orthopedics Shenzhen Children’s Hospital of China Medical UniversityShenzhenGuangdongChina Guangxi Medical University NanningGuangxiChina

Importance:There are a variety of musculoskeletal malformations and injuries that can occur in *** can be a significant cause of perinatal death or a reason for miscarriage and can lead to long-term functional issues if not managed *** is no systematic and well-established screening program for neonatal musculoskeletal malformations and injuries in China ***:To report the incidence and types of congenital musculoskeletal malformations in two hospitals in Shenzhen City,to explore and discuss the details of the screening procedure and improve future prevention and ***:From October 2013 to May 2014,2564 one-day-old newborns were screened by a pediatric orthopedic physical examination,in combination with ultrasonography when required,and the incidence and variety of diseases were recorded ***:Among 2564 screened newborns,the following musculoskeletal conditions were identified:congenital muscular torticollis(CMT)(seven cases,0.27%),hip subluxation(four cases,0.16%),hip dysplasia(47 cases,1.83%),congenital talipes equinovarus(CTEV)(two cases,0.08%),congenital talipes calcaneovalgus(15 cases,0.58%),polydactyly(nine cases,0.35%),syndactyly(one case,0.04%),and spinal hemivertebra(one case,0.04%).Additionally,there were five(0.19%)neonates with birth ***:It is feasible to carry out neonatal screening and identification of musculoskeletal malformations and birth injuries in *** is helpful as timely detection and early intervention for many of these conditions can avoid permanent functional impairment in these children.

关键词： Musculoskeletal system malformations Newborn Screening