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Chinese Physics B 2013年第10期22卷 281-286页

作者：赵宗清何卫华王剑郝轶丹曹磊峰谷渝秋张保汉 science and Technology on Plasma Physics Laboratory Laser Fusion research center China Academy of Engineering Physics

In inertial confinement fusion （ICF）, X-ray coded imaging is considered as the most potential means to diagnose the compressed core. The traditional Richardson-Lucy （RL） method has a strong ability to deblur the image where the noise follows the Poisson distribution. However, it always suffers from over-fitting and noise amplification, especially when the signal-to-noise ratio of image is relatively low. In this paper, we propose an improved deconvolution method for X-ray coded imaging. We model the image data as a set of independent Gaussian distributions and derive the iterative solution with a maximum-likelihood scheme. The experimental results on X-ray coded imaging data demonstrate that this method is superior to the RL method in terms of anti-overfitting and noise suppression.

关键词： inertial confinement fusion coded imaging deconvolution Gaussian distribution maximum-likelihood

Association of the solublewith schizophrenia: an observational study

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生物组学研究杂志(英文) 2020年第3期03卷 116-122页

作者： Cai Lei Yang Xuhan Kang Yani Wen Wen Zhang Fuquan Yue Weihua Zhang Qian Chen Fangyu Cao Wen Yue Jun Liang Meng Luo Na Sui Jing Fei Chunhua Tian Lin Qin Shengying Wan Chunling He Lin Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Collaborative Innovation center for Genetics and Development, Shanghai Jiao Tong university School of Biomedical Engineering, Bio-ID center, Shanghai Jiao Tong university, Shanghai Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical university, Nanjing, Jiangsu Province Institute of Mental health, the Sixth Hospital, Peking university, Beijing Shanghai Key Laboratory of Mycobacterium Tuberculosis, Shanghai Pulmonary Hospital, Tongji university School of Medicine, Shanghai School of Medical imaging and Tianjin Key Laboratory of Functional imaging, Tianjin Medical university, Tianjin Brainnetome center and National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of sciences, Beijing center of Mental health in Fengxian district, Shanghai Department of Psychiatry, Wuxi Mental health center, Nanjing Medical university, Wuxi, Jiangsu Province, China Bio-X Institutes Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education) Collaborative Innovation Center for Genetics and Development Shanghai Jiao Tong University School of Biomedical Engineering Bio-ID Center Shanghai Jiao Tong University Shanghai Department of Psychiatry The Affiliated Brain Hospital of Nanjing Medical University Nanjing Jiangsu Province Institute of Mental health the Sixth Hospital Peking University Beijing Shanghai Key Laboratory of Mycobacterium Tuberculosis Shanghai Pulmonary Hospital Tongji University School of Medicine Shanghai School of Medical imaging and Tianjin Key Laboratory of Functional imaging Tianjin Medical University Tianjin Brainnetome center and National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing center of Mental health in Fengxian district Shanghai Department of Psychiatry Wuxi Mental Health Center Nanjing Medical University Wuxi Jiangsu Province China

Objective: The immune system is involved in the pathogenesis of schizophrenia; here, we aimed to explore the relationship of cytotoxic T lymphocyte antigen 4.(CTLA4. with ***: CTLA4.gene structure was first analyzed, and then rs231779, rs733618, rs231775 and rs308724. were selected as tag single nucleotide polymorphisms for the linkage disequilibrium blocks inCTLA4.in the Chinese Han population to study expression quantitative trait loci ofCTLA4.gene in normal brain tissue. Additionally, membraneCTLA4.(mCTLA4. and solubleCTLA4.(sCTLA4. mRNA expression levels were evaluated in peripheral blood mononuclear cells from 65 first-episode schizophrenia patients and 61 healthy controls. This study was approved by the Bioethics Committee of corresponding research institutes (approval No. 20150016) on March 6, 2015 and the principles of theDeclaration of ***: After applying Bonferroni correction to theP values, only the minor C allele of rs733618 was significantly associated with increased expression of totalCTLA4.(PBonf.= 0.019), but notmCTLA4.(PBonf. = 0.115), in the hippocampus. ThesCTLA4.expression was significantly decreased in the peripheral blood mononuclear cells of schizophrenia patients compared with healthy controls, whilemCTLA4.was ***: These results suggest that the soluble form ofCTLA4.may be associated with schizophrenia and that lowersCTLA4.expression may increase the risk of developing schizophrenia.

关键词： CTLA4 expression quantitative trait loci qRT-PCR schizophrenia soluble form

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注意缺陷多动障碍的神经机制及干预

心理科学 2011年第4期34卷 931-938页

作者：冯刚毅朱祖德段懿行张卫华南师范大学教育科学学院/心理应用研究中心广州510631

注意缺陷多动障碍是一种常见的神经性、发展性障碍。大脑异常被认为是注意缺陷多动障碍的病因之一。随着脑成像技术的发展,当前对该障碍的脑解剖结构病变、脑神经发育迟缓和脑网络连接异常等方面都展开了深入研究。文章从以上三个方面... 详细信息

注意缺陷多动障碍是一种常见的神经性、发展性障碍。大脑异常被认为是注意缺陷多动障碍的病因之一。随着脑成像技术的发展,当前对该障碍的脑解剖结构病变、脑神经发育迟缓和脑网络连接异常等方面都展开了深入研究。文章从以上三个方面介绍最新研究成果,并指出目前的不足和未来研究方向,在此基础上为提高诊断精确性和发展新型有效的治疗干预方法提供建议。

关键词：注意缺陷多动障碍神经机制脑网络干预

A Molecular Dynamics Study on the (1120) Domain Boundary Structures in Epitaxial Wurtzite GaN

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Journal of Materials science & Technology 1999年第4期15卷 328-330页

作者： Shaoqing WANGt Yuanming WANG and Hengqiang YE(Laboratory of Atomic imaging of Solids, Institute of Metal research, Chinese Academy of sciences,Shenyang 110015, China)To whom correspondence should be addressedE-mail: sqwang@*** Laboratory of Atomic imaging of Solids Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

A computer program has been developed for the moIlcular dynamics calculation of ionic orstrong-ionic covalent systems. Ewald summation algorithm and Keating potentiaI model areadopted to calculate the long-range Coulomb interaction and the short-range bonding forces,respectively. A theoretical study on the domain boundary structures in epitaxial wurtzite GaN film is accomplished with the program. The calculation result is used in the structure formationexplanation of an interesting defect observed by HREM experiment.

关键词： Rev Domain Boundary Structures in Epitaxial Wurtzite GaN A Molecular Dynamics Study on the

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反射式扫描近场光学显微镜及其成像

中国激光 1998年第9期25卷 852-858页

作者：王刚赵钧刘静勇张培林清华大学现代应用物理系和单原子分子测控中心

介绍了一种光纤探针同时作为光源和探测器的反射式扫描近场光学显微镜，该装置通过采用相干探测、偏振分光等技术克服了该类显微镜所普遍面临的噪声背景干扰问题，具有较高的光学信噪比，并通过样品纵向振动调制锁相实现了对样品表面光... 详细信息

介绍了一种光纤探针同时作为光源和探测器的反射式扫描近场光学显微镜，该装置通过采用相干探测、偏振分光等技术克服了该类显微镜所普遍面临的噪声背景干扰问题，具有较高的光学信噪比，并通过样品纵向振动调制锁相实现了对样品表面光强梯度信号的探测成像，进一步改善了成像质量。成像研究表明该装置可对近场衰逝分量进行有效探测并实现了超衍射极限成像。

关键词： SNOM 反射模式衰逝波相干探测光学显微镜

Fast bowtie effect elimination for MODIS L1B data

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The Journal of China Universities of Posts and Telecommunications 2010年第1期17卷 120-126页

作者： REN Rui-zhi,GUO Shu-xu,GU Ling-jia College of electronic science and engineering,Jilin university,Changchun 130012,China College of electronic science and engineering Jilin University Changchun 130012 China

The bowtie effect refers to geometry distortions for the moderate resolution imaging spectrum-radiometer （MODIS） level 1B （L1 B） data. Till now, to eliminate the bowtie effect, numerous methods are proposed. However, most of them have limitations in computation efficiency. Through a comparative study of existing methods, this article puts forward a fast method to eliminate the bowtie effect using the ephemeris data. In this method, the rough positions of overlapping data are first detected. Because of the influence caused by the instrarnent characters and the earth＇s curvature, the positions of overlapping data need to be rectified to obtain more precise results. The optimal rectification method used in this article is selected by comparing three methods. By using the optimal method, the rectified MODIS data can be obtained. The experiments demonstrate that the bowtie effect can be eliminated in less than 1 s. In contrast, other traditional methods spend at least 3 s, thus the proposed method is faster and more effective.

关键词： bowtie effect MODIS bilinear interpolation overlapping data rectification

THE EFFECT OF IMU INACCURACIES ON AIRBORNE SAR imaging

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Journal of Electronics(China) 2011年第Z1期 409-418页

作者： Mao Yongfei* ** Xiang Maosheng* Wei Lideng* Han Songtao*** *(National Key Laboratory of science and Technology on Microwave imaging, Institute of Electronics, Chinese Academy of sciences, Beijing 100190, China) **(Graduate university of Chinese Academy of sciences, Beijing 100039, China) ***(Beijing Aerospace Control center, Beijing 100094. China)

When using motion compensation approaches based on the measurement of motion sensors, the residual uncompensated motion errors due to measurement instrument inaccuracies contribute to phase errors and hence degrade Synthetic Aperture Radar (SAR) images. This paper presents a model to compute the phase error caused by Inertial Measurement Unit (IMU) measurement inaccuracies. By analyzing SAR motion compensation method and the effect of lever arm, this model derives the con-tribution of each term of IMU inaccuracies towards the residual uncompensated motion errors and provides a method to calculate each order of the residual phase error. According to the model, com-puted results of the airborne X-band SAR system with POS AV510 accord closely with the actual image quality.

关键词： Synthetic Aperture Radar (SAR) Inertial Measurement Unit (IMU) Motion compen-sation Phase error

A COMPREHENSIVE INVESTIGATION ON A PECULIAR DEFECT IN WURTZITE GaN FILM

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Acta Metallurgica Sinica(English Letters) 1999年第4期12卷 327-333页

作者： S.Q.Wang1 ,2) and H.Q.Ye1) 1) Laboratory of Atomic imaging of Solids,Institute of Metal research , The Chinese Academy of sciences, Shenyang 110015 ,China 2)Department of Materials science and Metallurgy , {4. of Cambridge, Cambridge CB2 3QZ, UK

Apeculiar crystal defect was observed by experiment of high resolution electron microscopy( HREM) .It wasidentifiedtoformed bytwothreading dislocationsand asegmentof(11 20) domain boundary. An atomicstructure model was proposed for the anomalous defect. Theresultofthe weak beam experimentofelectron microscopeaffirmedthesuggested *** GaN(11 2 0) domain boundaries werestudied by Molec ular Dynamicscalculations. Thetheoreticalresultsshowedthatthelike atom bonding domain boundary, whichcomposesthe main partofthe peculiar defect, has much higher formationenergy than itcounterpartof unlike atom bonding domain boundary. Theoutcome providesanotherevidenceforthesuggested model.

关键词： HREM weak beam electron microscopy crystal defect Wurtzite GaN molecular dynamics

Molecular Dynamics Simulation of Zero-Fluence and Low-Bombarding-Energy ^(63)Cu-^(65)Cu Sputtering

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Journal of Materials science & Technology 1999年第2期15卷 184-186页

作者： Liping ZHENG Shi QIU and Yukui ZHOU (Shanghai Institute of Nuclear research, Chinese Academy of sciences, P.O.Box800-204. Shanghai 201800,China)Hisheng LI(Lab. of Atomic imaging of Solids, Institute of Metal research Chinese Academy of sciences, Shenyang Shanghai Institute of Nuclear research Chinese Academy of Sciences P.O.Box800-204 Shanghai 201800 China Lab. of Atomic imaging of Solids Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

A molecuIar dynamics simulation has been used to study zero-fluence and low- bombarding63Cu-65Cu sputtering. Calculations show that the isotopic ratios at both θ≤35° and energy 63Cu-65Cu sputtering. Calculations show that the isotopic ratios at both θ≤35° and θ >35°, and the total isotopic ratio increase when the bombarding energy decreases. This result might impty the existence of the bombarding-energy-dependent momentum asymmetry.

关键词： Simulation Cu Sputtering Molecular Dynamics Simulation of Zero-Fluence and Low-Bombarding-Energy