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All-optically integrated photoacoustic and optical coherence tomography:A review

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Journal of Innovative Optical Health Sciences 2017年第4期10卷 42-51页

作者： Wei Qiao Zhongjiang chen Ministry of Education Key laboratory of laser life Science and Institute of laser life Science College of Biophotonics South China Normal University Guangzhou 510631 China

All-optically integrated photoacoustic(PA)and optical coherence tomography(OCT)dualmode imaging technology that could o®er comprehensive pathological information for accurate diagnosis in clinic has gradually become a promising imaging technology in the aspect of biomedical imaging during the recent *** review refers to the technology aspects of alloptical PA detection and system evolution of optically integrated PA and OCT,including Michelson interferometer dual-mode imaging system,Fabry–Perot(FP)interferometer dualmode imaging system and Mach–Zehnder interferometer dual-mode imaging *** is believed that the optically integrated PA and OCT has great potential applications in biomedical imaging.

关键词： All-optical photoacoustic optical coherence tomography dual-mode imaging

Shear Induced Morphological Transformation of large Compound Micelles Formed by Glutathione End-capped Poly（4-vinylpyridine）

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Chinese Journal of Chemistry 2013年第6期31卷 745-751页

作者： yifei Wang Daoyong chen State Key laboratory of Molecular Engineering of Polymers Department of Macromolecular Science Fudan University Shanghai 200433 China

Here we report novel shear-sensitive polymeric large compound micelles （lCMs） formed by self-assembly of glutathione end-capped poly（4-vinylpyridine）（GP4VP） in water containing 4 vol% methanol. The amphiphile prefers to form the kinetieally stabilized lCMs due to the small length ratio of the hydrophilic part to the hydrophobic part; the encapsulation of the hydrophilic part within lCMs causes only a small enthalpy loss from a thermody- namic view. Sheared by vortex flows generated by vigorous stir, the lCMs evolve to thick wall vesicles, thin wall vesicles, broken vesicles and ＂pearl-necklace＂ structures consecutively. The high flexibility of the lCMs and the internal tension caused by the encapsulation of the hydrophilic part are responsible for the high shear sensitivity of the lCMs.

关键词： shear sensitive large compound micelle morphological transformation

Optimization of the S-band side-coupled cavities for proton acceleration

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Nuclear Science and Techniques 2020年第3期31卷 1-9页

作者： Hao-yun li Xin-Miao Wan Wei chen chen-Hui Shi Zhi-Hui li The Key laboratory of Radiation Physics and Technology of Ministry of Education Institute of Nuclear Science and Technology Sichuan University

The proton beam with energy around 100 MeV has seen wide applications in modern scientific research and in various ***,proton sources in China fall short for meeting experimental needs owing to the vast size and expensive traditional proton *** Institute of Nuclear Science and Technology of Sichuan University proposed to build a 3 GHz side-coupled cavity linac(SCl)for re-accelerating a 26 MeV proton beam extracted from a CS-30 cyclotron to 120 *** carried out investigations into several vital factors of S-band SCl for proton acceleration,such as optimization of SCl cavity geometry,end cell tuning,and bridge coupler *** demonstrated that the effective shunt impedance per unit length ranged from 22.5 to 59.8 MX/m throughout the acceleration process,and the acceleration gradient changed from 11.5 to 15.7 MV/m when the maximum surface electric field was equivalent to Kilpatrick electric *** obtained equivalent circuit parameters of the biperiodic structures and applied them to the end cell tuning;results of the theoretical analysis agreed well with the 3D *** designed and optimized a bridge coupler based on the previously obtained biperiodic structure parameters,and the field distribution un-uniformness was\1.5%for a two-tank *** radio frequency power distribution system of the linac was obtained based on the preliminary beam dynamics design.

关键词： Proton beam Side-coupled cavity linac Accelerating cavity Biperiodic structure Bridge coupler

lOEN:lensless opto-electronic neural network empowered machine vision

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light(Science & Applications) 2022年第6期11卷 1118-1129页

作者： Wanxin Shi Zheng Huang Honghao Huang chengyang Hu Minghua chen Sigang yang Hongwei chen Beijing National Research Center for Information Science and Technology(BNRist) Department of Electronic EngineeringTsinghua UniversityBeijing 100084China

Machine vision faces bottlenecks in computing power consumption and large amounts of *** opto-electronic hybrid neural networks can provide assistance,they usually have complex structures and are highly dependent on a coherent light source;therefore,they are not suitable for natural lighting environment *** this paper,we propose a novel lensless opto-electronic neural network architecture for machine vision *** architecture optimizes a passive optical mask by means of a task-oriented neural network design,performs the optical convolution calculation operation using the lensless architecture,and reduces the device size and amount of calculation *** demonstrate the performance of handwritten digit classification tasks with a multiple-kernel mask in which accuracies of as much as 97.21%were ***,we optimize a large-kernel mask to perform optical encryption for privacy-protecting face recognition,thereby obtaining the same recognition accuracy performance as no-encryption *** with the random MlS pattern,the recognition accuracy is improved by more than 6%.

关键词： neural network electronic

Oxidative stress in Alzheimer's disease

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Neuroscience Bulletin 2014年第2期30卷 271-281页

作者： Zhichun chen Chunjiu Zhong Department of Neurology Zhongshan Hospital The State Key laboratory of Medical Neurobiology Fudan University The Institutes of Brain Science Fudan University

Oxidative stress plays a significant role in the pathogenesis of Alzheimer＇s disease （AD）, a devastating disease of the elderly. The brain is more vulnerable than other organs to oxidative stress, and most of the components of neurons （lipids, proteins, and nucleic acids） can be oxidized in AD due to mitochondrial dysfunction, increased metal levels, inflammation, and β-amyloid （Aβ） peptides. Oxidative stress participates in the development of AD by promoting Aβ deposition, tau hyperphosphorylation, and the subsequent loss of synapses and neurons. The relationship between oxidative stress and AD suggests that oxidative stress is an essential part of the pathological process, and antioxidants may be useful for AD treatment.

关键词： Alzheimer's disease oxidative stress β-amyloid tau metals antioxidants

MicroRNAs recruit eIF4E2 to repress translation of target mRNAs

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Protein & Cell 2017年第10期8卷 750-761页

作者： Shaohong chen Guangxia Gao CAS Key laboratory of Infection and Immunity CAS Center for Excellence in Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100101 China

MicroRNAs （miRNAs） recruit the RNA-induced silencing complex （RISC） to repress the translation of target mRNAs. While the 5＇ 7-methylguanosine cap of target mRNAs has been well known to be important for miRNA repression, the underlying mechanism is not clear. Here we show that TNRC6A interacts with elF4E2, a homo- Iogue of eIF4E that can bind to the cap but cannot interact with eIF4G to initiate translation, to inhibit the translation of target mRNAs. Downregulation of eIF4E2 relieved miRNA repression of reporter expression. Moreover, eIF4E2 downregulation increased the protein levels of endogenous IMP1, PTEN and PDCD4, whose expression are repressed by endogenous miRNAs. We further provide evidence showing that miRNA enhances elF4E2 association with the target mRNA. We propose that miRNAs recruit eI4E2 to compete with eIF4E to repress mRNA translation.

关键词： microRNAs translation repression 5' cap eIF4E2. TNRC6A

Exact quantum and TST-CEQ study of the collinear reaction O+HCl

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Chinese Journal of Chemistry 1995年第4期13卷 299-305页

作者： JU, GZ chen, DZ NANJING UNIV DEPT CHEMNANJING 210008PEOPLES R CHINA SHANDONG NORMAl UNIV DEPT CHEMJINAN 250014PEOPLES R CHINA

Exact quantum calculations of reaction probabilities have been carried out using hyperspherical coordinates for the collinear reaction O+HCl(upsilon less than or equal to 1)-->OH(upsilon' less than or equal to 1)+Cl. A generalized lEPS potential energy surface with a barrier height of 8.12 kcal/mol has been used in the calculations. According to the calculated results we found that (1) the reaction probability oscillates with energy, (2) the reaction probability shows vibrational adiabaticity, although it is poorer than that for symmetric reaction Cl+HCl. The analysis of resonance has also been done. The reaction rate constants and average cross sections have been calculated by TST-CEQ method. The rate constants are in agreement with that by QCT and smaller than the experimental one. Finally, the threshold has been estimated and is in good agreement with that of the literature.

关键词： QUANTUM SCATTERING HyDROGEN CHlORIDE CROSS SECTION RATE CONSTANT

Metadynamic recrystallization and microstructure evolution of a continuously cast Ti-microalloyed steel slab with heavy reduction

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Journal of Iron and Steel Research International 2022年第1期29卷 103-114页

作者： Zi-jian Wei cheng Ji Tian-ci chen Miao-yong Zhu chen-hui Wu Key laboratory for Ecological Metallurgy of Multimetallic Ores(Ministry of Education) Shenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina Pangang Group Research Institute Co. Ltd.Panzhihua 617000SichuanChina

The effects of the deformation parameters in the heavy reduction(HR)process on recrystallization kinetics and microstructure evolution were *** on the experimental results,metadynamic recrystallization(MDRX)kinetic and austenite grain size models were established for a continuously cast slab during ***,the evolution of the quenched microstructure after MDRX was observed using electron backscatter *** relative frequency of very low-angle grain boundaries decreased from 58.8% to 52.1%,and the relative frequency of high-angle grain boundaries increased from 28.5% to 38.9%.Analyses revealed that the recovery was the main softening *** decrease in the total grain boundary length indicated that subgrain growth occurred with increasing inter-pass *** main texture evolved from a {001}texture to a{112}texture,and the texture strength remained unchanged.

关键词： Microalloyed steel Heavy reduction Metadynamic recrystallization Microstructure evolution Kinetic model

Invariance principles for the law of the iterated logarithm under G-framework

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Science China Mathematics 2015年第6期58卷 1251-1264页

作者： WU Panyu chen ZengJing Qilu Securities Institute for Financial Studies Shandong University School of Mathematics Shandong University

We obtain a general invariance principle of G-Brownian motion for the law of the iterated logarithm(lIl for short). For continuous bounded independent and identically distributed random variables in G-expectation space, we also give an invariance principle for lIl. In some sense, this result is an extension of the classical Strassen's invariance principle to the case where probability measure is no longer additive. Furthermore,we give some examples as applications.

关键词： iterated logarithm invariance expectation Brownian continuity union satisfy automatically details