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EXISTENCE AND STABILITY OF VISCOUS SHOCK PROFILES FOR 2-D ISENTROPIC MHD WITH INFINITE ELECTRICAL RESISTIVITY

Acta Mathematica Scientia 2010年第2期30卷 447-498页

作者： Blake Barker Olivier Lafitte Kevin Zumbrun Department of Mathematics Indiana University LAGA Institut GalileeUniversite Paris 1393 430 Villetaneuse and CEA SaclayDM2S/DIR91 191 Gif sur Yvette CedexFrance

For the two-dimensional Navier-Stokes equations of isentropic magnetohydrodynamics （MHD） with γ-law gas equation of state, γ≥ 1, and infinite electrical resistivity, we carry out a global analysis categorizing all possible viscous shock profiles. Precisely, we show that the phase portrait of the traveling-wave ODE generically consists of either two rest points connected by a viscous Lax profile, or else four rest points, two saddles and two nodes. In the latter configuration, which rest points are connected by profiles depends on the ratio of viscosities, and can involve Lax, overcompressive, or undercompressive shock profiles. Considered as three-dimensional solutions, undercompressive shocks axe Lax-type （Alfven） waves. For the monatomic and diatomic cases γ= 5/3 and γ=7/5, with standard viscosity ratio for a nonmagnetic gas, we find numerically that the the nodes are connected by a family of overcompressive profiles bounded by Lax profiles connecting saddles to nodes, with no undercompressive shocks occurring. We carry out a systematic numerical Evans function analysis indicating that all of these two-dimensional shock pro- files are linearly and nonlinearly stable, both with respect to two- and three-dimensional perturbations. For the same gas constants, but different viscosity ratios, we investigate also cases for which undercompressive shocks appear; these are seen numerically to be stable as well, both with respect to two-dimensional and （in the neutral sense of convergence to nearby Riemann solutions） three-dimensional perturbations.

关键词： stability of viscous shock waves Evans function magnetohydrodynamics

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Orf1/SpcS Chaperones ExoS for Type Three Secretion by Pseudomonas aeruginosa

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Biomedical and Environmental Sciences 2008年第2期21卷 103-109页

作者： DA-KANG SHEN LAURIANE QUENEE MARIETTE BONNET LAURIANE KUHN MADIHA DEROUAZI DANIELE LAMOTTE BERTRAND TOUSSAINT BENOIT POLACK Groupe de Recherche et d'Etude du Processus Inflammatoire (GREPI) MENRT EA 2938 Centre Hospitalier Universitaire de Grenoble BP 217 38043 Grenoble Cedex 9 France Laboratoire de Chimie des Protéines DRDC CEA Grenoble 38054 Grenoble France

Objective Pseudomonas aeruginosa is a ubiquitous and opportunistic pathogen that uses the type Ⅲ secretion system （TTSS） to inject effector proteins directly into the cytosol of target cells to subvert the host cell＇s functions. Specialized bacterial chaperones are required for effective secretion of some effectors. To identify the chaperone of ExoS, the representative effector secreted by the TTSS of P aeruginosa, we analyzed the role of a postulated chaperone termed Orfl. Methods By allelic exchange, we constructed the mutant with the deletion of gene Orfl. Analysis of secreted and cell-associated fractions was performed by SDS-PAGE and Western blotting. Using strain expressing in trans Orfl, tagged by V5 polypeptide and histidine, protein-protein interaction was determined by affinity resin pull-down assay in combination with MALDI-TOF The role of Orfl in the expression of exoS was evaluated by gene reporter analysis. Results Pull-down assay showed that Orfl binds to ExoS and ExoT. Secretion profile analysis showed that Orfl was necessary for the optimal secretion of ExoS and ExoT. However, Orfl had no effect on the expression of exoS. Conclusion Orfl is important for the secretion of ExoS probably by maintaining ExoS in a secretion-competent conformation. We propose to name Orfl as SpcS for ＂specific Pseudomonas chaperone for ExoS＂.

关键词： Type Ⅲ secretion system Pseudomonas aeruginosa Chaperone

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Processing Seismic Ambient Noise Data to Obtain Reliable Surface Wave Dispersion Measurements

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中国地震研究：英文版 2015年第2期29卷 214-224页

作者： Li Lingli Wang Weitao Zhu Liangbao Chen Haopeng Wang Qingdong Miao Peng Wang Jun Earthquake Administration of Anhui Province Mengcheng National Geophysical Observatory Institute of Geophysics cea Department of Geophysics School of Geodesy and GeometricsWuhan University

Ambient noise tomography is a rapidly emerging field of seismological research. This paper presents the current status of ambient noise data processing and its development history over the past several years, with the intention to explain and justify this development through salient examples. The ambient noise data processing procedure can be divided into four principal phases:1 single station data preparation; 2 crosscorrelation and temporal stacking; 3 measurements of dispersion curves( p erformed with frequency-time analysis for both group and phase speeds); 4 quality control,i ncluding SNR analysis and selection of the acceptable measurements. In addition,we provide a specific solution for a better use of the seismic station data to ambient noise study.

关键词：地震环境噪声数据测量面波频散环境噪声时间分析交叉相关性层析成像

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An Introduction to the Latest-generation Spatial Database of Active Tectonics of China

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Earthquake Research in China 2009年第2期23卷 237-243页

作者： Qu Chunyan Deng Qidong State Key Laboratory of Earthquake Dynamics Institute of Geology CEA Beijing 100029 China

Based on ArcGIS and MapInfo software, we digitized the active tectonics map (1:4,000,000) of China, which was compiled and revised by academician Deng Qidong, and built the spatial database of active tectonics of China. The database integrates rich active tectonic data, such as a catalogue of earthquakes with magnitude above 6.0, active faults, Quaternary basins, active folds and their associated attribute parameters, and implements scientific and effective management to this data. At the same time, the spatial database joins the spatial map data and the associated attribute data together, which implements the data query between spatial properties and attribute parameters and also makes it possible to perform spatial analysis with different data layers. These provide much convenience for earthquake study and allows engineering construction institutions to use this data in practical applications.

关键词：空间数据库理论数据处理地震学

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Optical results of the black hole microquasar SS 433

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 153-156页

作者： LI Hui1,2 & YAN JingZhi1,3 1 Purple Mountain Observatory,Chinese Academy of Sciences,Nanjing 210008,China 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,China 3 Service d’Astrophysique,cea Saclay and University Paris Diderot,91191 Gif-sur-Yvette,France Purple Mountain Observatory Chinese Academy of Sciences Nanjing China Graduate University of Chinese Academy of Sciences Beijing China Service d’Astrophysique CEA Saclay and University Paris Diderot Gif-sur-Yvette France

We present optical spectroscopic observations of SS 433 during different precessional and orbital phases.Our 2004,2007 and 2008 data provide us a good chance to study the variability of the Hα line at different orbital phases for nearly the same disk inclination.The data show that the Hα of SS 433 usually had a symmetric profile between orbital phases 0.25-0.75,while an asymmetric structure with a strong red peak was observed for other orbital phases.We suggest that the orbital variability of Hα emission is connected with accretion flow from the donor star to the accretion disk.In addition,we attribute the dramatic increase of Hα emission during our 2007 observational run,which had a time scale of one day,to the emergence of strong jets.

关键词： high-mass X-ray binary black hole spectroscopy outflow wind relativistic jet

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An alternative evolution scenario for OAO 1657-415 and IGR J18483-0311

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 130-134页

作者： LIU QingZhong1,2,LI Hui1,3 & YAN JingZhi1,2 1 Purple Mountain Observatory,Chinese Academy of Sciences,Nanjing 210008,China 2 Service d’Astrophysique,cea Saclay and University Paris Diderot,91191 Gif-sur-Yvette,France 3 Graduate University of Chinese Academy of Sciences,Beijing 100049,China Purple Mountain Observatory Chinese Academy of Sciences Nanjing China Service d’Astrophysique CEA Saclay and University Paris Diderot Gif-sur-Yvette France Graduate University of Chinese Academy of Sciences Beijing China

The relation between the spin period and the orbital period in high-mass X-ray binaries is investigated.Be/X-ray binaries and SG/X-ray binaries occupy different areas in Corbet's diagram.The two SG/X-ray binaries,IGR J18483-0311 and OAO 1657-415,however,appear to occupy a transition region between Be/X-ray binaries and wind-fed SG/X-ray binaries.This can be understood by noting that the neutron stars in the two SG/X-ray binaries have not reached their equilibrium spin periods when the donors evolved off the main sequence.Here,we provide an alternative scenario to explain their location in Corbet's diagram:the SG/X-ray binaries are the descendants of Be/X-ray binaries,i.***.the supergiants in these systems were formed from O-type emission line stars instead of normal main-sequence stars.Furthermore,we suggest that there are two types of SG/X-ray binaries:one is directly evolved from a normal OB-type main sequence and neutron star system without an X-ray history,and the other evolved from a Be/X-ray binary with an X-ray history.

关键词： high-mass X-ray binary pulsar Corbet’s diagram stellar evolution

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The Deformation of Active Tectonic Blocks on the Chinese Mainland and Its Relationship with Seismic Activity

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Earthquake Research Advances 2004年第1期 57-69页

作者： Wang Hui 1) , Zhang Guomin 1) , Wu Yun 2) and Ma Hongsheng 1) 1) Center for Analysis and Prediction, China Earthquake Administration, Beijing 100036, China 2) Institute of Seismology, cea, Wuhan 430071, China Center for Analysis and Prediction China Earthquake Administration Beijing 100036 China Institute of Seismology CEA Wuhan 430071 China

Based on the hypothesis of the active tectonic blocks on the Chinese continent and its adjacent regions (both the method of the DDA on a spherical surface and the GPS survey results observed from 1991 to 2001 are used), the movements and deformations of each active tectonic block are calculated. The calculation results show that although the movements and deformations of active tectonic blocks in the eastern region and in the western region of China are different, active tectonic blocks in the same active tectonic block region are coherent. Then, the relative velocities of the active tectonic blocks’ boundary zones are calculated, and the relationship between current crustal motion and strong seismic activities is discussed. Earthquakes ( M S≥7 0) on the Chinese continent since 1988 all occurred on boundary zones of active tectonic blocks with high slipping speed.

关键词： Active tectonic blocks DDA on spherical surface GPS survey results Seismic activity

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Field Geological Exploration of the Ashikule Volcano Group in Western Kunlun Mountains

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Earthquake Research Advances 2012年第2期 152-159页

作者： Xu Jiandong1), Zhao Bo1), Zhang Liuyi1), and Chen Zhengquan2) 1) Key Laboratory of Active Tectonics and Volcano, Institute of Geology, cea, Beijing 100029, China 2) College of Resource Environment and Tourism, Capital Normal University, Beijing 100048, China Key Laboratory of Active Tectonics and Volcano Institute of Geology CEA Beijing 100029 China College of Resource Environment and Tourism Capital Normal University Beijing 100048 China

From May 4 to May 30, 2011, a field exploration of the Ashikule basin in the Western Kunlun Mountains area was conducted by a research team from the Institute of Geology, China Earthquake Administration and Earthquake Administration of Xinjiang Uygur Autonomous Region. This work is financially supported by the special fund for China earthquake research project "The Comprehensive Scientific Exploration of the MS7.3 Yutian Earthquake in 2008 and the Ashikule Volcano Group". Through detailed field survey on geological and geomorphological features of the Ashikule volcano group, which is one of the highest altitude volcanic plateaus (about 5000m) in the world, we have determined the total number of volcanoes, the eruption type and structural parameters, and approximate active history of the volcano group. Our studies have provided field evidence for resolving past controversies such as the authenticity of the news report about the eruption event on May 27, 1951, the eruption pattern of the Daheishan volcano, and the reality of the Gaotaishan volcano.

关键词： Ashikule volcano group Recent eruption Volcano cone Lava

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Clinical/Behavioral Monitoring of Rodents and Rabbits Undergoing Scientific Experiments

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Open Journal of Veterinary Medicine 2024年第5期14卷 91-109页

作者： Luiz Cesar Cavalcanti Pereira Jhônata Willy Rocha Coelho Hyago da Silva Medeiros Elidio Rita de Cássia dos Passos Ferraz Da Silva João Gabriel Regis Sobral Bárbara Alves de Brito Soledade Leandro Thomaz Vilela Isabele Barbieri Dos Santos Institute of Science and Technology in Biomodels (ICTB) Oswaldo Cruz Foundation (FIOCRUZ) Rio de Janeiro Brazil Laboratory Animal Facility of the Carlos Chagas Pavilion of the Animal Experimentation Center (cea) Oswaldo Cruz Institute (IOC) Oswaldo Cruz Foundation (FIOCRUZ) Rio de Janeiro Brazil

Background: We currently have international and national guidelines regarding the assessment and monitoring of clinical signs and humane endpoints in animals used in teaching and research, which make the performance of these activities mandatory for any experiment and professional working in this area. Assigning the severity of a research experiment is the result of an analysis of records of observations of the animal’s behavior, and clinical signs. The aim of this study was to describe the importance of carrying out a severity assessment associated with clinical and behavioral monitoring of rodents and rabbits during experimentation to maintain the welfare of these animals undergoing scientific research. Methods: The literature search was carried out using the following terms: “Monitoring”;“Humane endpoints”;“Animal welfare”, “Rodents”;“Rabbits”, and as connectors “and”;“or”, in the following databases: PubMed;LILACS/BIREME and SciELO. Results: A total of 987 articles were identified in the databases, and 20 of these studies were included in this review. Conclusions: Humane endpoint protocols and procedure severity tables are of the utmost importance, both from an ethical point and to refine the results of research conducted on laboratory animals. They should be drawn up jointly by the teams responsible for the project and the maintenance of the animals during the research period, and the data obtained should be published so that the scientific community can have access to it, helping to disseminate these practices, as well as helping to draw up new procedures. Monitoring and evaluating the welfare and clinical condition of animals undergoing scientific research procedures is the responsibility of the professors, researchers, veterinarians, and animal facility coordinators. The Ethics Committee on the Use of Animals must monitor all the activities conducted with the animals, by inspecting the experimental procedures and the physical environment of the laboratory animal facility where the animals are housed.

关键词： Monitoring Humane Endpoints Animal Welfare Experimental Design Laboratory Animals’ Investigations

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Measurement and characteristics of ground vibration caused by blasting demolition of urban overpass

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Engineering Sciences 2014年第6期12卷 100-106页

作者： Hu Jinjun Yang Yongqiang Guan Yingjun Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering Mechanics CEA Harbin 150080 China College of Earth Science University of Chinese Academy of Sciences Beijing 100049 China

To analyze the characteristics of ground vibration caused by blasting demolition of urban overpass,in this paper we introduced the measurement method and then studied the characteristics of recorded ground vibrations.Through the analysis of peak acceleration,peak frequency and duration,results indicated that the vertical component of vibration is the most important in the region close to the collapse point;the collapse of bridge segments will lead to superposition of ground vibration,and isolation measures can reduce the peak acceleration but increase the duration of vibration;blasting and collapse vibration cause no damage to the reserved structure which indicates that blasting demolition is a safe and effective method.

关键词：地面振动城市立交桥爆破拆除测量方法峰值加速度持续时间峰值频率垂直分量

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