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Measurements of the parapapillary atrophy area and other fundus morphological features in high myopia with or without posterior staphyloma and myopic traction maculopathy

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International Journal of Ophthalmology(English edition) 2020年第8期13卷 1272-1280页

作者： Xiao-Xiao Guo Xi Chen Shan-Shan li Min li xiu-fen Yang Lu Zhao Ran You Yan-ling Wang Department of Ophthalmology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Clinical Epidemiology and EBM Unit National Clinical Research Center for Digestive Disease Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China

AIM:To investigate the affecting factors of parapapillary gamma and delta zones and other fundus morphological features in high ***:Seventy high myopia patients were included in this retrospective observational study and 47 patients were *** were divided into three groups:no posterior staphyloma(no PS),PS with myopic traction maculopathy(PS with MTM),and PS without MTM using 3-dimensional magnetic resonance imaging and optical coherence *** patients were fur ther classified into three types[epiretinal membrane,macular hole,and macular retinoschisis(MRS)].Diameters of the gamma and delta zones were measured among other morphometric variables using fundus ***:Of the 70 individuals(127 eyes),the mean age was 57.46±*** univariate analysis,morphological features changed most dramatically in PS with MTM patients,who had the largest gamma zone diameters,the largest disk-fovea distance(DFD)and disk-fovea angle,and the smallest angle kappa and vertical distance of temporal arterial ***,their horizontal delta zone diameter was smaller than in the patients with PS yet without *** multivariate analysis,with axial length(AL)and age adjusted,the horizontal diameter in the delta zone of the PS without MTM group was still significantly larger than in the PS with MTM group(P=0.024).Comparing the three subtypes of MTM patients,the diameters of the gamma zone and DFD in MRS group were the ***:The characteristics of the gamma and delta zones change inconsistently in different stages of high *** changes may be associated with anatomical changes caused by local *** such as PS,AL and age play an important *** findings may provide a hint about the pathogenesis of traction in high myopia.

关键词： high myopia myopization myopic traction maculopathy parapapillary delta zone parapapillary gamma zone posterior staphyloma

Low Dimensional Chaos from the Group Sunspot Numbers

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Chinese Journal of Astronomy and Astrophysics 2007年第3期7卷 435-440页

作者： Qi-xiu li Ke-Jun li National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 Graduate School of Chinese Academy of Sciences Beijing 100049

We examine the nonlinear dynamical properties of the monthly smoothed group sunspot number Rg and find that the solar activity underlying the time series of Rg is globally governed by a low-dimensional chaotic attractor. This finding is consistent with the nonlinear study results of the monthly Wolf sunspot numbers. We estimate the maximal Lyaponuv exponent （MLE） for the Rg series to be positive and to equal approximately 0.0187 ± 0.0023 （month^- 1）. Thus, the Lyaponuv time or predictability time of the chaotic motion is obtained to be about 4.46 ± 0.5 years, which is slightly different with the predictability time obtained from Rz. However, they both indicate that solar activity forecast should be done only for a short to medium term due to the intrinsic complexity of the time behavior concerned.

关键词： Sun activity - Sun sunspot - chaos - Sun Wolf sunspot numbers

Diffusion Bonding of Al6061 and Cu by Hot Isostatic Pressing

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Journal of Wuhan University of Technology(Materials Science) 2020年第1期35卷 183-191页

作者：滕庆 li xiu WEI Qingsong State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China

Diffusion bonding between Al and Cu was successfully performed by hot isostatic pressing(HIP). To improve the strength of diffusion bonding joint, pure nickel foils with different thickness were used as intermediate layer. Microstructure of the interface between Al and Cu was investigated by X-ray diffraction(XRD) technique, secondary electron microscopy(SEM), and nano-indentation tests. When the temperature was 500 ℃ and held for 3 h with a processing pressure of 50 MPa, Al and Cu could be bonded with its interface formed by several diffusion layers. With the addition of Ni interlayer, the diffusion of aluminum atoms was effectively hindered, and the interface became smoother. The tensile strength of bonded joints increases with increasing the thickness of Ni interlayer, which contributes to a reduction in the thickness of intermetallic compounds(IMCs) and well bonding quality of Al-Cu joints.

关键词： hot isostatic pressing diffusion bonding aluminum copper IMCs hardness

Theoretical Study on Reaction Mechanism of Aluminum-Water System

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Chinese Journal of Chemical Physics 2008年第3期21卷 245-249页

作者： Yun-lan Sun Yan Tian Shu-fen li Department of Chemical Physics University of Science and Technology of China Hefei 230026 China School of Metallurgy and Resources Anhui University of Technology Maanshan 243002 China

A theoretical study on the reaction of aluminum with water in the gas phase was performed using the hybrid density functional B3LYP and QCISD（T） methods with the 6-311＋G（d,p） and the 6-311＋＋G（d,p） basis sets. The results show that there are three possible reaction pathways that involve four isomers, seven transition structures, and two possible products for the reaction of aluminum with water. The two most favorable reaction pathways were found, whose intermediates and products agreed quite well with experimental results. The enthalpy and Gibbs free energy change of the reaction between A1 and H2O at 298 and 2000 K were calculated. Some results are also in good agreement with the previous calculations or experimental results.

关键词： Aluminum Water Reaction mechanism Hybrid density functional theory

The causes and impacts for heat stress in spring maize during grain filling in the North China Plain--A review

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Journal of Integrative Agriculture 2016年第12期15卷 2677-2687页

作者： TAO Zhi-qiang CHEN Yuan-quan li Chao ZOU Juan-xiu YAN Peng YUAN Shu-fen WU Xia SUI Peng college of Agronomy and Biotechnology China Agricultural University Beijing 100193 P.R.China Institute of Crop Science Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and Ecology Ministry of Agriculture Beijing 100081 P.R.China Wuqiao Experimental Station China Agricultural University Cangzhou 061800 P.R. China

High-temperature stress （HTS） at the grain-filling stage in spring maize （Zea mays L.） is the main obstacle to increasing productivity in the North China Plain （NCP）. To solve this problem, the physiological mechanisms of HTS, and its causes and impacts, must be understood. The HTS threshold of the duration and rate in grain filling, photosynthetic characteristics （e.g., the thermal stability of thylakoid membrane, chlorophyll and electron transfer, photosynthetic carbon assimilation）, water status （e.g., leaf water potential, turgor and leaf relative water content） and signal transduction in maize are reviewed. The HTS threshold for spring maize is highly desirable to be appraised to prevent damages by unfavorable temperatures during grain filling in this region. HTS has negative impacts on maize photosynthesis by damaging the stability of the thylakoid membrane structure and degrading chlorophyll, which reduces light energy absorption, transfer and photosynthetic carbon assimilation. In addition, photosynthesis can be deleteriously affected due to inhibited root growth under HTS in which plants decrease their water-absorbing capacity, leaf water potential, turgor, leaf relative water content, and stomatal conductance. Inhibited photosynthesis decrease the supply of photosynthates to the grain, leading to falling of kernel weight and even grain yield. However, maize does not respond passively to HTS. The plant transduces the abscisic acid （ABA） signal to express heat shock proteins （HSPs）, which are molecular chaperones that participate in protein refolding and degradation caused by HTS. HSPs stabilize target protein configurations and indirectly improve thylakoid membrane structure stability, light energy absorption and passing, electron transport, and fixed carbon assimilation, leading to improved photosynthesis. ABA also induces stomatal closure to maintain a good water status for photosynthesis. Based on understanding of such mechanisms, strategies for alleviat

关键词： North China Plain spring maize grain filling heat-tolerance heat-avoidance gas exchange water status

Efficacy of one-day quadruple therapy for H pylori infection in Chinese patients

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World Journal of Gastroenterology 2006年第19期12卷 3105-3107页

作者： Xiao-Hui Huo Jian-Kun Chu xiu-fen Yang Jing Wang li-Jing Zhang Jin-Cheng Ma Jun Yu Department of Gastroenterology First Affiliated Hospital of Hebei Medical University Shijiazhuang Hebei Province China Department of Medicine and Therapeutics Prince of Wales Hospital Chinese University of Hong Kong Hong Kong China

AIM： TO compare the efficacies of one-day quadruple therapy and seven-day triple therapy in Chinese patients. METHODS： Sixty consecutive patients with nonulcer dyspepsia and confirmed H pylori infection were randomized to receive either omeprazole 40 mg, amoxycillin 1 g, and furazolidone 100 mg, all twice a day for 7 d or omeprazole 20 mg （at breakfast and dinner）, amoxicillin 1 g, furazolidone 200 mg, and colloidal bismuth subcitrate 220 mg four times for only one day. H pylori status was determined before and at least 5 weeks after therapy by endoscopy with antral and corpus biopsies for rapid urease test and histology. RESULTS： Hpyloi eradication was successful in 66.67% （20/30） patients in the 7-d group and in 36.67% （11/30） patients in the 1-day group （P = 0.037）. Side effects were induced by the treatment in 13.3% （4/30） patients of each group, but these were all self-limiting, shortlasting, and did not require any specific treatment. CONCLUSION： The one-day quadruple therapy is less effective than the one-week regimen in curing H pylori infection in Chinese patients.

关键词： H pylori Quadruple therapy Antibiotics Gastritis Side effects

Two-dimensional shallow water equations with porosity and their numerical scheme on unstructured grids

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Water Science and Engineering 2013年第1期6卷 91-105页

作者： Zhi-li WANG Yan-fen GENG State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute School of Transportation Southeast University

In this study, porosity was introduced into two-dimensional shallow water equations to reflect the effects of obstructions, leading to the modification of the expressions for the flux and source terms. An extra porosity source term appears in the momentum equation. The numerical model of the shallow water equations with porosity is presented with the finite volume method on unstructured grids and the modified Roe-type approximate Riemann solver. The source terms of the bed slope and porosity are both decomposed in the characteristic direction so that the numerical scheme can exactly satisfy the conservative property. The present model was tested with a dam break with discontinuous porosity and a flash flood in the Toce River Valley. The results show that the model can simulate the influence of obstructions, and the numerical scheme can maintain the flux balance at the interface with high efficiency and resolution.

关键词： shallow water equations with porosity source term," Roe-type Riemann solver," finitevolume method unstructured grid

Novel Approach to Nonlinear PID Parameter Optimization Using Ant Colony Optimization Algorithm

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Journal of Bionic Engineering 2006年第2期3卷 73-78页

作者： Duan Hai-bin Wang Dao-bo Yu xiu-fen School of Automation Science and Electrical Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 P. R. China College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China Centre for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 P. R. China

This paper presents an application of an Ant Colony Optimization （ACO） algorithm to optimize the parameters in the design of a type of nonlinear PID controller. The ACO algorithm is a novel heuristic bionic algorithm, which is based on the behaviour of real ants in nature searching for food. In order to optimize the parameters of the nonlinear PID controller using ACO algorithm, an objective function based on position tracing error was constructed, and elitist strategy was adopted in the improved ACO algorithm. Detailed simulation steps are presented. This nonlinear PID controller using the ACO algorithm has high precision of control and quick response.

关键词： Ant Colony Optimization algorithm pheromone nonlinear PID parameter optimization

Nematodes feel a craving- Using Caenorhabditis elegans as a model to study alcohol addiction

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Neuroscience Bulletin 2014年第4期30卷 595-600页

作者： Geng Zhu fen Zhang Wei li School of life Sciences Institute Tongji University

Alcohol is the most frequently-used addictive drug. However, the mechanism by which its consumption leads to addiction remains largely elusive. Given the conservation of behavioral reactions to alcohol, Caenorhabitis elegans （C. elegans） has been effectively used as a model system to investigate the relevant molecular targets and pathways mediating these responses. In this article, we review the roles of BK channels （also called SLO-1）, the lipid microenvironment, receptors, the synaptic machinery, and neurotransmitters in both the acute and chronic effects of alcohol. We provide an overview of the genes and mechanisms involved in alcoholism- related behaviors in C. elegans.

关键词： C. elegans substance abuse ethanol BK channel