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Impact of Cloud Microphysical Processes on the Simulation of Typhoon Rananim near Shore. Part II： Typhoon Intensity and Track

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Acta meteorologica Sinica 2011年第4期25卷 456-466页

作者： CHENG Rui YU Rucong xu Youping fu Yunfei State Key Laboratory of Numerical Simulation for Atmo3pheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics CAS Beijing 100029 Graduate School of the Chinese Academy of Sciences Beijing 100049 University of Science and Technology of China Hefei 230026

The impact of cloud microphysical processes on the simulated intensity and track of Typhoon Rananim is discussed and analyzed in the second part of this study. The results indicate that when the cooling effect due to evaporation of rain water is excluded, the simulated 36-h maximum surface wind speed of Typhoon Rananim is about 7 m s-1 greater than that from all other experiments; however, the typhoon landfall location has the biggest bias of about 150 km against the control experiment. The simulated strong outer rainbands and the vertical shear of the environmental flow are unfavorable for the deepening and maintenance of the typhoon and result in its intensity loss near the landfall. It is the cloud microphysical processes that strengthen and create the outer spiral rainbands, which then increase the local convergence away from the typhoon center and prevent more moisture and energy transport to the inner core of the typhoon. The developed outer rainbands are supposed to bring dry and cold air mass from the middle troposphere to the planetary boundary layer （PBL）. The other branch of the cold airflow comes from the evaporation of rain water itself in the PBL while the droplets are falling. Thus, the cut-off of the warm and moist air to the inner core and the invasion of cold and dry air to the eyewall region are expected to bring about the intensity reduction of the modeled typhoon. Therefore, the deepening and maintenance of Typhoon Rananim during its landing are better simulated through the reduction of these two kinds of model errors.

关键词： typhoon intensity cloud microphysical processes spiral rainband environmental wind shear

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蛹虫草水提物影响人胃癌细胞BGC-823不同RCD通路的转录组分析

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食品工业科技 2025年第4期46卷 1-9页

作者：崔明琦于凯雯宋扬徐方旭王升厚王泽沈阳师范大学生命科学学院辽宁沈阳110034 辽宁省功能性蛹虫草重点实验室辽宁沈阳110034 沈阳师范大学实验教学中心辽宁沈阳110034

目的：基于转录组测序技术，分析预测蛹虫草（XG）水提物影响人胃癌细胞BGC-823生长活性的主要调节性细胞死亡（Regulated cell death，RCD）信号通路。方法：MTT法测定XG水提物对胃癌细胞增殖能力的影响，转录组测序分析显著差异基因及... 详细信息

目的：基于转录组测序技术，分析预测蛹虫草（XG）水提物影响人胃癌细胞BGC-823生长活性的主要调节性细胞死亡（Regulated cell death，RCD）信号通路。方法：MTT法测定XG水提物对胃癌细胞增殖能力的影响，转录组测序分析显著差异基因及其KEGG富集情况，获得凋亡、自噬、坏死性凋亡及铁死亡信号通路的hub基因（10个）。通过激光共聚焦、流式细胞术、qRT-PCR进一步验证XG水提物对胃癌细胞凋亡的诱导情况。结果：XG水提物对人胃癌细胞BGC-823生长活性的抑制作用具有剂量依赖特征。转录组测序共筛选到5885个差异表达基因，并在凋亡（P=0.001）及自噬（P=0.008）信号通路存在显著性富集，除铁死亡外，其它信号通路的hub基因的表达量均被显著性抑制，包括caspase依赖性凋亡信号通路的关键因子CASP3、CASP9、CASP7和APAF1，自噬小体形成相关的基因ULK1、ULK2、UVRAG、Atg14及Atg5。细胞学检测结果显示，胃癌细胞经XG水提物处理后呈典型的凋亡形态学特征，早期凋亡率为24.8%，细胞周期阻滞于G2/M期。qRT-PCR检测显示，BCL2、BCL2L1、CASP3、CASP9及XIAP的表达受到显著抑制（P<0.01），ENDOG和AIF表达量上调明显（P<0.01），与转录组测序结果一致。结论：蛹虫草主要通过Caspase非依赖性线粒体凋亡途径抑制人胃癌细胞BGC-823的生长活性，同时可以影响自噬等信号通路的激活，为蛹虫草在功能性食品的开发提供理论支持。

关键词：蛹虫草凋亡自噬坏死性凋亡铁死亡

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Synchronization and Exponential Estimates of Complex Networks with Mixed Time-varying Coupling Delays

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International Journal of Automation and computing 2009年第3期6卷 301-307页

作者： Yang Dai Yun-ze Cai Xiao-Ming xu Department of Automation Shanghai Jiao Tong University Shanghai 200240 PRC University of Shanghai for Science and Technology Shanghai 200093 PRC Shanghai Academy of Systems Science Shanghai 200093 PRC

Exponential estimates and sufficient conditions for the exponential synchronization of complex dynamical networks with bounded time-varying delays are given in terms of linear matrix inequalities （LMIs）. A generalized complex networks model involving both neutral delays and retarded ones is presented. The exponential synchronization problem of the complex networks is converted equivalently into the exponential stability problem of a group of uncorrelated delay functional differential equations with mixed timevarying delays. By utilizing the free weighting matrix technique, a less conservative delay-dependent synchronization criterion is derived. An illustrative example is provided to demonstrate the effectiveness of the proposed method.

关键词： Complex networks synchronization exponential estimates neutral delay time-varying delay.

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A Trot and Flying Trot Control Method for Quadruped Robot Based on Optimal Foot Force Distribution

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Journal of Bionic Engineering 2019年第4期16卷 621-632页

作者： Teng Chen Xiaobo Sun ze xu Yibin Li xuewen Rong Lelai Zhou Center for Robotics School of Control Science and EngineeringShandong UniversityJinan 250061China

In order to enhance the dynamic motion capability of the bionic quadruped robot,a flying trot gait control method based on full-scale virtual model and optimal plantar force distribution is proposed.A stable flying trot gait is accomplished by mapping the robot torso motion to the foot *** force distribution calculated by the torso virtual model is converted into a quadratic optimization problem and solved in real time by the open source library *** transition between the trot gait and the flying trot gait is achieved by coordinating leg motion *** results of the dynamic simulation verify that the proposed method can realize the 3D stable flying trot *** against the trot gait,the flying trot gait can improve the speed of the quadruped *** the trot gait and the flying trot gait,the quadruped robot can move efficiently and adapt to complex terrains.

关键词： quadruped robot flying trot virtual model control quadratic optimization

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Statistical assessment of selection-based dual-hop semi-blind amplify-and-forward cooperative networks

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第10期11卷 785-792页

作者： Yi LIU Jian-hua ZHANG Wei xu ze-min LIU Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China MOE Key Lab of Universal Wireless Communications Beijing University of Posts and Telecommunications Beijing 100876 China

For multiple-relay cooperative networks with multiple antennas deployed at source and destination nodes,we investigate the outage performance of selection based semi-blind amplify-and-forward(AF) relaying,where transmit beamforming(TB) is conducted at source transmission and maximum ratio combining(MRC) at destination *** on the Kolmogorov-Smirnov test,we analyze the impact of the configuration of destination antennas on the outage performance under arbitrary Nakagami-m fading *** reveal that increasing the number of destination antennas is not necessary for an improvement of outage performance with any Nakagami-m *** by this fact,an approximation is proposed for the optimal *** results show that the approximation is an efficient selection method.

关键词： Semi-blind relaying Transmit beamforming (TB) Maximum ratio combining (MRC) Relay selection

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Dynamics of loose granular flow and its subsequent deposition in a narrow mountainous river

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Journal of Mountain Science 2019年第6期16卷 1367-1380页

作者： LEI Ming xu ze-xing ZHAO Tao WANG Xie-kang State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

A large amount of loose debris materials were deposited on the slope of mountainous areas after the 2008 Ms 8.0 Wenchuan earthquake. During and after the earthquake, these loose debris deposits collapsed and slide into valleys or rivers, changing river sediment supply condition and channel morphology. To investigate the mechanisms of granular flow and deposition, the dynamics of slope failure and sediment transportation in typical mountainous rivers of different intersection angles were analyzed with a coupling model of Computational Fluid Dynamics and Discrete Element Method(CFD-DEM). The numerical results show that the change of intersection angle between the granular flow flume and the river channel can affect the deposit geometry and the fluid flow field significantly. As the intersection angle increases, the granular velocity perpendicular to the river channel increases, while the granular velocity parallel to the river channel decreases gradually. Compared to the test of dry granular flow, the CFD-DEM coupling tests show much higher granular velocity and larger volume of sediments entrained in the river. Due to the river flow, particles located at the edge of the deposition will move downstream gradually and the main section of sediments deposition moves from the center to the edge of the river channel. As a result, sediment supply in the downstream river will distribute unevenly. Under the erosion of fluid flow, the proportion of fine particles increases, while the proportion of coarse particles decreases gradually in the sediment deposition. The build-up of accumulated sediment mass will cause a significant increase in water level in the river channel, thus creating serious flooding hazard in mountainous rivers.

关键词： Loose debris materials Sediment supply CFD-DEM coupling method Numerical simulations

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L2-LBMT:A Layered Load Balance Routing Protocol for Underwater Multimedia Data Transmission

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Journal of Ocean University of China 2017年第6期16卷 1018-1026页

作者： LV ze TANG Ruichun TAO Ye SUN Xin xu Xiaowei College of Information Science and Engineering Ocean University of China Department of Information Technology Qingdao University of Science and Technology

Providing highly efficient underwater transmission of mass multimedia data is challenging due to the particularities of the underwater environment. Although there are many schemes proposed to optimize the underwater acoustic network communication protocols, from physical layer, data link layer, network layer to transport layer, the existing routing protocols for underwater wireless sensor network(UWSN) still cannot well deal with the problems in transmitting multimedia data because of the difficulties involved in high energy consumption, low transmission reliability or high transmission delay. It prevents us from applying underwater multimedia data to real-time monitoring of marine environment in practical application, especially in emergency search, rescue operation and military field. Therefore, the inefficient transmission of marine multimedia data has become a serious problem that needs to be solved urgently. In this paper, A Layered Load Balance Routing Protocol(L2-LBMT) is proposed for underwater multimedia data transmission. In L2-LBMT, we use layered and load-balance Ad Hoc Network to transmit data, and adopt segmented data reliable transfer(SDRT) protocol to improve the data transport reliability. And a 3-node variant of tornado(3-VT) code is also combined with the Ad Hoc Network to transmit little emergency data more quickly. The simulation results show that the proposed protocol can balance energy consumption of each node, effectively prolong the network lifetime and reduce transmission delay of marine multimedia data.

关键词： underwater wireless multicast multimedia data transmission load balance

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Calculations of Energy-Loss function for 26 Materials

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Chinese Journal of Chemical Physics 2016年第6期29卷 663-670,I0001页

作者： Yang Sun Huan xu Bo Da Shi-feng Mao ze-jun Ding HefeiNationalLaboratoryforPhysicalSciencesattheMicroscaleandDepartmentofPhysics UniversityofScienceandTechnologyofChinaHefei230025China

We present a fitting calculation of energy-loss function for 26 bulk materials, including 18 pure elements （Ag, A1, Au, C, Co, Cs, Cu, Er, Fe, Ge, Mg, Mo, Nb, Ni, Pd, Pt, Si, Te） and 8 compounds （AgCl, Al2O3, AlAs, CdS, SiO2, ZnS, ZnSe, ZnTe） for application to surface electron spectroscopy analysis. The experimental energy-loss function, which is derived from measured optical data, is fitted into a finite sum of formula based on the Drude-Lindhard dielectric model. By checking the oscillator strength-sum and perfect- screening-sum rules, we have validated the high accuracy of the fitting results. further-more, based on the fitted parameters, the simulated reflection electron energy-loss spec- troscopy （REELS） spectrum shows a good agreement with experiment. The calculated fitting parameters of energy loss function are stored in an open and online database at http：//***/ELF/***.

关键词： Energy loss function Dielectric function Optical data

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Preparation and Properties of Zirconium Hydrideon the surface of MCM-41 Mesoporous Molecular Sieves

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Chemical Research in Chinese Universities 2001年第4期17卷 426-431页

作者： WANG xu-xu fu Xian-zhi LEFEBVRE Frederic BASSET Jean-Marie Research Institute of Photocatalysis Fuzhou UniversityFuzhou 350002P.R.China Laboratoire de Chimie Organometallique de Surface UMR CNRS-CPE 998643Bd dull Novembre 11 Novembre 191869616 Villeurbanne CedexFrance

Zirconium monohydride bonded to the framework oxygen of MCM-41 surface was prepared by the reaction of tetraneopentyl zirconium with MCM-41 surface hydroxyl groups, followed by the hydrogenolysis of the resulted product. The surface hydride was characterized by using infrared spectroscopy, solid-state NMR, elemental analysis, gas-phase chromatography and chemical probing reaction. It was shown that this surface species is stable below 150 ’C and can catalytically crack alkanes into methane and ethane at 100 .

关键词： MCM-41 Zirconium hydride Grafting reaction Catalytic cracking

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L-type Calcium Channels are Involved in Iron-induced Neurotoxicity in Primary Cultured Ventral Mesencephalon Neurons of Rats

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Neuroscience Bulletin 2020年第2期36卷 165-173页

作者： Yu-Yu xu Wen-Ping Wan Sha Zhao ze-Gang Ma Department of Physiology School of Basic MedicineQingdao UniversityQingdao 266071China Institute of Brain Science and Disorders Qingdao UniversityQingdao 266071China

In the present study,we investigated the mechanisms underlying the mediation of iron transport by Ltype Ca^2+ channels(LTCCs)in primary cultured ventral mesencephalon(VM)neurons from *** found that cotreatment with 100 lmol/L FeSO4 and MPP^+(1-methyl-4-phenylpyridinium)significantly increased the production of intracellular reactive oxygen species,decreased the mitochondrial transmembrane potential and increased the caspase-3 activation compared to MPP^+ treatment ***-treatment with 500 lmol/L CaCl2 further aggravated the FeSO4-induced neurotoxicity in MPP^+-treated VM ***-treatment with 10 lmol/L isradipine,an LTCC blocker,alleviated the neurotoxicity induced by co-application of FeSO4 and FeSO4/*** studies indicated that MPP^+treatment accelerated the iron influx into VM *** addition,FeSO4 treatment significantly increased the intracellular Ca^2+ *** effects were blocked by *** results suggest that elevated extracellular Ca^2+ aggravates ironinduced *** mediate iron transport in dopaminergic neurons and this,in turn,results in elevated intracellular Ca^2+ and further aggravates iron-induced neurotoxicity.

关键词： L-type Ca^2+channels Iron overload Parkinson’s disease Isradipine Dopamine neuron

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