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Polymer/silica hybrid waveguide Y-branch power splitter with loss compensation based on NaYF4:Er3+, Yb3+ nanocrystals

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Chinese Physics B 2019年第10期28卷 354-359页

作者： Yue-Wu Fu tong-He sun Mei-Ling Zhang Xu-Cheng Zhang Fei Wang Da-Ming Zhang State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China College of Communication Engineering Jilin UniversityChangchun 130012China

A polymer waveguide Y-branch power splitter with loss compensation is proposed based on NaYF4:Er^3+, Yb^3+ nanocrystals prepared by a high temperature thermal decomposition method. The Y-branch power splitter is designed as a structure of embedded waveguide, and its core material is nanocrystals-doped SU-8. The insertion loss of the device is ~ 15 dB. For an input signal power of 0.05 mW and a pump power of 267.7 mW, the two branches with 5.81-dB and5.41-dB loss compensations at 1530 nm are achieved respectively. A polymer waveguide Y-branch power splitter with loss compensation has an important research significance.

关键词： polymer NaYF4:Er Yb loss compensation

光谱及成像技术在果蔬损伤检测研究中的应用现状与展望

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光谱学与光谱分析 2022年第9期42卷 2657-2665页

作者：周童童孙晓林孙志忠彭何欢孙通胡栋浙江农林大学光机电工程学院浙江杭州311300 浙江农林大学数学与计算机科学学院浙江杭州311300

果蔬在收获、运输、贮藏、分拣、包装和销售过程中均会遭受不同程度的挤压、碰撞或摩擦,从而造成果蔬损伤,如挤伤、开裂、擦伤等外部损伤,同时,在生长过程中会产生黑心、水心、褐腐、霉心等内部损伤。果蔬损伤初期特征不明显,外观与正... 详细信息

果蔬在收获、运输、贮藏、分拣、包装和销售过程中均会遭受不同程度的挤压、碰撞或摩擦,从而造成果蔬损伤,如挤伤、开裂、擦伤等外部损伤,同时,在生长过程中会产生黑心、水心、褐腐、霉心等内部损伤。果蔬损伤初期特征不明显,外观与正常果实基本无异,然而随着时间的推移,损伤组织恶化扩散,最终导致整个果实腐烂变质,又进而接触感染其他果实,造成周边甚至整箱果蔬病变,对果蔬产业造成巨大的经济损失。果蔬采后损伤检测方法多种多样,其中人工检测最为简单常用,但是该方法不仅耗时耗力,容易造成错判和漏判现象,而且无法实现肉眼不可见的皮下或内部损伤检测。近年来,随着计算机技术的快速发展,越来越多的无损检测技术被广泛应用于果蔬损伤检测,其中最为常用的当属光谱和成像技术。光谱成像技术通常结合图像处理、光谱分析、化学计量学方法、统计分析等手段,利用损伤果蔬和正常果蔬的图谱信号差异实现损伤检测,具有无损、快速等优点,能解决人工检测耗时耗力且准确率低的问题。在此主要概述了8种光谱及成像技术(近红外光谱、拉曼光谱、荧光光谱、高光谱成像、空间频域成像、核磁成像、X射线成像和热成像)在果蔬损伤检测的最新研究进展,包括检测原理及其技术特点,总结分析了各技术在果蔬损伤检测方面的应用情况,并展望未来发展趋势,以期为果蔬损伤无损检测提供借鉴与参考。

关键词：果蔬无损检测光谱技术成像技术损伤

Characteristic fractional step finite difference method for nonlinear section coupled system

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Applied Mathematics and Mechanics(English Edition) 2014年第10期35卷 1311-1330页

作者：袁益让李长峰孙同军刘允欣 Institute of Mathematics Shandong University School of Economics Shandong University

For the section coupled system of multilayer dynamics of fluids in porous media, a parallel scheme modified by the characteristic finite difference fractional steps is proposed for a complete point set consisting of coarse and fine partitions. Some tech- niques, such as calculus of variations, energy method, twofold-quadratic interpolation of product type, multiplicative commutation law of difference operators, decomposition of high order difference operators, and prior estimates, are used in theoretical analysis. Optimal order estimates in 12 norm are derived to show accuracy of the second order approximation solutions. These methods have been used to simulate the problems of migration-accumulation of oil resources.

关键词： three-dimensional section coupled system complete nonlinear equation,characteristic fractional step convergence numerical simulation

STRUCTURE OF THERMOTROPIC LIQUID CRYSTALLINE VANILLIC ACID/P-HYDROXYBENZOIC ACID/ETHYLENE TEREPHTHALATE VHE TERPOLYESTERS

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Chinese Chemical Letters 1992年第3期3卷 207-210页

作者： Xin Gui LI Mei Rong HUANG Gui He GUAN tong sun Institute of Membrane Separation Engineering Tianjin Institute of Textile Science and TechnologyTianjin300160 Department of Chemical Fiber Technology Chi na Textile UniversityShanghai200051

Thermotropic liquid crystalline VHE terpolyesters made from vanillic acid (V),p-hydroxybenzoic acid (H) and poly(ethylene terephthalate) (E) were studied by 400 MHz NMR spectra, wide angle X-ray diffraction,scanning electron and polarizing *** was found that the VHE terpolyesters had random sequence *** VHE terpolyester films exhibited highly oriented fibrillar structure.

关键词： ACID STRUCTURE OF THERMOTROPIC LIQUID CRYSTALLINE VANILLIC ACID/P-HYDROXYBENZOIC ACID/ETHYLENE TEREPHTHALATE VHE TERPOLYESTERS OC MHz

The Evidence of Institutional Investors' Herd Behavior and the Research on Market Simulation

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International Journal of Plant Engineering and Management 2013年第1期18卷 1-7页

作者： XIA Wei-li sun tong-tong WEI Xing-ji School of Management Northwestern Polytechnical University

In the context of vigorously developing China＇s securities market institutional investors in the period of economic transition, this paper does the empirical research on the herd behavior from the view of the interaction between individual and institutional investors. This paper adopts the standard deviation of trading volume the cross-section to measure herd behavior. The results show that no matter what the market is in bull status and bear status, institutional investors perform herd behavior and with the expansion of the shareholding scale in a bull market, the herd behavior is higher, which suggests that the vigorous development of institutional investors has not eliminated herd behavior. This paper further confirms that there is the endogenous volatility in the market based on an artificial stock market. Finally it is demonstrated the herd behavior of institutional investors cause abnormal fluctuations in the market.

关键词： herd behavior volatility institutional investors

Effect of intestinal ischemia-reperfusion on expressions of endogenous basic fibroblast growth factor and transforming growth factor β in lung and its relation with lung repair

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World Journal of Gastroenterology 2000年第3期6卷 353-355页

作者： Xiao Bing Fu Yin Hui Yang tong Zhu sun Xiao Man Gu Li Xian Jiang Xiao Oing sun Zhi Yong Sheng Research Laboratory,304th Hospital of PLA,Beijing 100037,China Research Laboratory 304th Hospital of PLA Beijing 100037 China

AIM To study the changes of endogenoustransforming growth factor β(TGFβ)and basicfibroblast growth factor(bFGF)in lung followingintestinal ischemia and reperfusion injury andtheir effects on lung injury and *** Sixty Wistar rats were divided intofive groups,which underwent sham-operation,ischemia(45 minutes),and reperfusion(6,24and 48 hours,respectively)after ischemia(45minutes).Immunohistochemical method wasused to observe the localization and amounts ofboth growth *** Positive signals of both growthfactors could be found in normal lung,mainly inalveolar cells and endothelial cells of *** and reperfusion insult,expressions ofboth growth factors were increased and theiramounts at 6 hours were larger than those ofnormal control or of 24 and 48 hours after *** The endogenous bFGF and TGF βexpression appears to be up-regulated in thelung following intestinal ischemia andreperfusion,suggesting that both growth factorsmay be involved in the process of lung injury andrepair.

关键词： lung intestinal ischemiareperfusion injury basic fibroblast growth factor transforming growth factor p

Desulfovibrio desulfuricans aggravates atherosclerosis by enhancing intestinal permeability and endothelial TLR4/NF-kB pathway in Apoe^(-/-) mice

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Genes & Diseases 2023年第1期10卷 239-253页

作者： Kun Zhang Xian Qin Juhui Qiu tong sun Kai Qu Ahmad Ud Din Wenhua Yan Tianhan Li Yidan Chen Wei Gu Xiancai Rao Guixue Wang Key Laboratory for Biorheological Science and Technology of Ministry of Education State and Local Joint Engineering Laboratory for Vascular ImplantsCollege of BioengineeringChongqing UniversityChongqing 400044China College of Information and Management Sciences Henan Agricultural UniversityZhengzhouHenan 450046China School of Medicine Chongqing UniversityChongqing 400030China Department of Microbiology College of Basic Medical SciencesArmy Medical University(Third Military Medical University)Chongqing 400037China

It is increasingly aware that gut microbiota is closely associated with ***,which and how specific gut bacteria regulate the progression of atherosclerosis is still poorly *** this study,modified linear discriminant analysis was performed in comparing the gut microbiota structures of atherosclerotic and non-atherosclerotic mice,and Desulfovibrio desulfuricans(***)was found to be associatedwith ***-treated Apoe^(-/-) mice showed significantly aggravated *** proatherogenic effect of *** was attributed to its ability to increase intestinal permeability and subsequent raise in the transit of lipopolysaccharide(LPS)from the intestine to the *** LPS in the blood can elicit local and systemic inflammation and activate Toll-like receptor 4(TLR4)/nuclear factor-kB(NF-kB)signaling of endothelial ***-242,a specific inhibitor of TLR4,can ameliorate the development of *** atherosclerosis by blocking the LPS-induced activation of TLR4/NF-kB signaling.

关键词： Atherosclerosis Desulf ovibrio desulfuricans Gut microbiota Linear discriminant analysis TAK-242

Temperature-dependent structure and magnetization of YCrO_(3)compound

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Chinese Physics B 2022年第4期31卷 493-499页

作者： Qian Zhao Ying-Hao Zhu Si Wu Jun-Chao Xia Peng-Fei Zhou Kai-tong sun Hai-Feng Li Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoAvenida da UniversidadeTaipaMacao SAR 999078China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Guangdong–Hong Kong–Macao Joint Laboratory for Neutron Scattering Science and Technology Dongguan 523803China

We have grown a YCrO_(3)single crystal by the floating-zone method and studied its temperature-dependent crystalline structure and magnetization by x-ray powder diffraction and PPMS DynaCool *** diffraction patterns were well indexed by an orthorhombic structure with space group of Pbnm(No.62).From 36 K to 300 K,no structural phase transition occurs in the pulverized YCrO_(3)single *** antiferromagnetic phase transition temperature was determined as T_(N)=141.58(5)K by the magnetization versus temperature *** found weak ferromagnetic behavior in the magnetic hysteresis loops below ***,we demonstrated that the antiferromagnetism and weak ferromagnetism appear simultaneously upon *** lattice parameters(a,b,c,and V)deviate downward from the Grüneisen law,displaying an anisotropic magnetostriction *** extracted temperature variation of the local distortion parameterΔ.Compared to theΔvalue of Cr ions,Y,O1,and O2 ions show one order of magnitude largerΔvalues indicative of much stronger local lattice ***,the calculated bond valence states of Y and O2 ions have obvious subduction charges.

关键词： orthochromates x-ray powder diffraction crystal structure magnetization

Exendin-4 and linagliptin attenuate neuroinflammation in a mouse model of Parkinson's disease

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Neural Regeneration Research 2023年第8期18卷 1818-1826页

作者： Hai-Yang Yu tong sun Zhen Wang Hong Li Duo Xu Jing An Lu-Lu Wen Jia-Yi Li Wen Li Juan Feng Department of Neurology Shengjing Hospital of China Medical UniversityShenyangLiaoning ProvinceChina Department of Pediatrics Shengjing Hospital of China Medical UniversityShenyangLiaoning ProvinceChina Laboratory of Research in Parkinson’s Disease and Related Disorders Health Sciences InstituteChina Medical UniversityShenyangLiaoning ProvinceChina Neural Plasticity and Repair Unit Department of Experimental Medical ScienceLund UniversityLundSweden

Use of glucagon-like peptide-1 receptor agonist or dipeptidyl peptidase 4 inhibitor has been shown to lower the incidence of Parkinson's disease in patients with diabetes ***,using these two treatments may help treat Parkinson's *** further investigate the mechanisms of action of these two compounds,we established a model of Parkinson's disease by treating mice with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and then subcutaneously injected them with the glucagon-like peptide-1 receptor agonist exendin-4 or the dipeptidyl peptidase 4 inhibitor *** found that both exendin-4 and linagliptin reversed motor dysfunction,glial activation,and dopaminergic neuronal death in this *** addition,both exendin-4 and linagliptin induced microglial polarization to the anti-inflammatory M2 phenotype and reduced pro-inflammatory cytokine ***,in vitro experiments showed that treatment with exendin-4 and linagliptin inhibited activation of the nucleotide-binding oligomerization domain-and leucine-rich-repeat-and pyrin-domaincontaining 3/caspase-1/interleukin-1βpathway and subsequent pyroptosis by decreasing the production of reactive oxygen *** findings suggest that exendin-4 and linagliptin exert neuroprotective effects by attenuating neuroinflammation through regulation of microglial polarization and the nucleotidebinding oligomerization domain-and leucine-rich-repeat-and pyrin-domain-containing 3/caspase-1/interleukin-1βpathway in a mouse model of Parkinson's disease induced by 1-methyl-4-phenyl-1,2,3,***,these two drugs may serve as novel anti-inflammatory treatments for Parkinson's disease.

关键词： diabetes mellitus dipeptidyl peptidase 4 inhibitor exendin-4 glucagon-like peptide-1 receptor agonist 1-methyl-4-phenyl-1 2 3 6-tetrahydropyridine linagliptin microglia neuroinflammation NLRP3 inflammasome Parkinson's disease pyroptosis