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Science China Earth Sciences 2020年第3期63卷 425-438页

作者： He HUANG Xuzhang SHEN Xuzhou LIU yuansheng zhang Lanzhou Institute of Seismology China Earthquake AdministrationLanzhou 730000China School of Earth Sciences and Engineering Sun Yat-Sen UniversityGuangzhou 510275China

Based on observations from a dense broadband seismic array located along the northeastern (NE) margin of the Tibetan Plateau in southeastern Gansu Province,we use receiver functions (RFs) to pick the arrival times of P-to-S converted waves and bin the traces in different grids according to the piercing points of the 410 and 660 km discontinuities in the upper *** depths of the two discontinuities are estimated by the ray tracing method with the IASP91 velocity model and a 3-D tomography *** results indicate the following:(1) The arrival times of the P410s and P660s converted phases are delayed by approximately 1 s than those predicted by the IASP91 *** mantle transition zone (MTZ) is thicker than that in the global model.(2) The synchronous lags in the P410s and P660s arrival times are consistent with low-velocity anomalies in the upper mantle,which are believed to result mainly from the eastward migration of materials beneath the NE margin of the Tibetan Plateau.(3) Combined with previous tomography results,the depression of the'660'discontinuity and the thickened MTZ are somewhat consistent with the big mantle wedge (BMW) ***,due to data limitations,more studies are required to explore the BMW in the future.

关键词： NE margin of the Tibetan Plateau Upper mantle discontinuities Low-velocity anomalies Receiver functions

Static Optimization of a Compliant Vertical Access Riser

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Journal of Ocean University of China 2019年第5期18卷 1070-1078页

作者： LOU Min zhang yuansheng WU Wugang College of Petroleum Engineering China University of Petroleum (East China)Qingdao 266580China Kunming Shipborne Equipment Research and Test Center China Shipbuilding Industry CorporationKunming 650051China

The compliant vertical access riser (CVAR) is a new riser concept with good compliance;it can significantly reduce operating costs by eliminating the need for additional machines to operate wells directly on the *** this study,we determined the optimal riser parameters in terms of the stress and riser weight by optimizing the CVAR,and we compared the optimization resuits.A two-dimensional nonlinear static CVAR model was deduced according to the principles of virtual work and variation,and the model was verified using *** of experiments and Kriging method were used to reduce the number of sample calculations and improve the modeling *** appropriate selection of the multi-objective optimization problem (MOP) and the non-dominated sorting genetic algorithm helped to optimize the CVAR *** non-dominated sorting genetic algorithm Ⅱ was used to solve the Pareto frontier of the optimization model in order to provide decision makers with more choices for the optimization *** optimizing the riser parameters,the geometry of the riser was smoother,and the stress and stress differences were greatly reduced;the maximum equivalent stresses at the top and bottom were reduced by 36.6% and 44%,*** addition,the stress difference in the buoyancy block area was reduced by 20.9%,and the weight of the riser was increased significantly by 28.1%.

关键词： compliant vertical access riser multi-objective optimization two-dimensional nonlinear static CVAR model

THZ1缓解心肌肥大保护射血分数降低的心力衰竭小鼠心脏功能的机制研究

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中西医结合心脑血管病杂志 2025年第3期23卷 371-377页

作者：赵勇陈佳显张远生海南医科大学第二附属医院海口570203

目的:探讨细胞周期蛋白依赖性激酶7(CDK7)抑制剂THZ1对射血分数降低的心力衰竭(HFrEF)小鼠心肌肥大和心脏功能的保护作用并探讨其作用机制。方法:将10周龄雄性C57BL/6小鼠成年应用永久性冠状动脉结扎术诱导HFrEF小鼠模型(HFrEF组,12只)... 详细信息

目的:探讨细胞周期蛋白依赖性激酶7(CDK7)抑制剂THZ1对射血分数降低的心力衰竭(HFrEF)小鼠心肌肥大和心脏功能的保护作用并探讨其作用机制。方法:将10周龄雄性C57BL/6小鼠成年应用永久性冠状动脉结扎术诱导HFrEF小鼠模型(HFrEF组,12只),12只小鼠接受假手术(sham组)。54只小鼠行冠状动脉结扎术,将存活的36只小鼠分为HFrEF组、THZ1组、THZ1+Colivelin TFA组,每组12只小鼠。THZ1组静脉注射THZ1,THZ1+Colivelin TFA组静脉注射THZ1与信号转导与转录激活因子3(STAT3)激活剂Colivelin TFA静脉注射。比较各组心重/胫骨长度比(HW/TL)、心肥大指数(HWI)、左室肥大指数(LVWI)、左室射血分数(LVEF)、左室短轴缩短率(LVFS)、左室前壁厚度(LVAWd)、左室后壁厚度(LVPWd)、左室舒张末期内径(LVEDD)、左室收缩末期内径(LVESD)、左室短轴缩短分数(LVFS)、左室舒张期容积(LVdVol)、左室收缩期容积(LVsVol)。实时荧光定量聚合酶链式反应(RT-q PCR)或大白免疫(Western Blot)检测各组小鼠心肌组织中CDK7、STAT3、Tyr705磷酸化的STAT3(p-STAT3)表达。结果:与sham组比较,HFrEF组HW/TL、HWI、LVWI、LVEF、LVFS、LVAWd、LVPWd、LVEDD、LVESD、LVFS、LVdVol、LVsVol均明显增加(P<0.05),且CDK7、STAT3、p-STAT3的表达均明显增加(P<0.05)。与HFrEF组比较,THZ1组HW/TL、HWI、LVWI、LVEF、LVFS、LVAWd、LVPWd、LVEDD、LVESD、LVdVol、LVsVol均明显降低(P<0.05),且CDK7、STAT3、p-STAT3表达均被抑制(P<0.05)。与THZ1组比较,THZ1+Colivelin TFA组HW/TL、HWI、LVWI、LVEF、LVFS、LVAWd、LVPWd、LVEDD、LVESD、LVdVol、LVsVol的指标均增加(P<0.05)。结论:CDK7抑制剂THZ1通过抑制STAT3缓解心肌肥大并改善HFrEF小鼠的心脏功能。

关键词：射血分数降低的心力衰竭细胞周期蛋白依赖性激酶7抑制剂 THZ1 信号传导与转录激活子3 心肌肥大心脏功能实验研究

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Numerical simulation of temperature field of AZ91D magnesium alloy during equal channel angular extrusion

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Acta Metallurgica Sinica(English Letters) 2010年第1期23卷 35-40页

作者： Xiaohua zhang yuansheng CHENG Shouting LUO School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

The temperature field of AZ91D magnesium alloy extruded by equal channel angular extrusion （ECAE） has been simulated using finite element method （FEM）. A series of tests were designed to obtain the simulation parameters： flow stress of AZglD, friction factor and heat transfer coefficient. The simulated temperature agrees well with the measured one. The evolution of temperature and influencing factor was discussed in details. Furthermore. the extrusion pressure of ECAE was analyzed.

关键词： Simulation Temperature field ECAE AZ91D Magnesium alloy

Crustal velocity structure of central Gansu Province from regional seismic waveform inversion using firework algorithm

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Earthquake Science 2017年第2期30卷 81-89页

作者： Yanyang Chen Yanbin Wang yuansheng zhang Department of Geophysics School of Earth and Space SciencesPeking University Lanzhou Institute of Seismology China Earthquake Administration

The firework algorithm（FWA） is a novel swarm intelligence-based method recently proposed for the optimization of multi-parameter, nonlinear functions. Numerical waveform inversion experiments using a synthetic model show that the FWA performs well in both solution quality and efficiency. We apply the FWA in this study to crustal velocity structure inversion using regional seismic waveform data of central Gansu on the northeastern margin of the Qinghai-Tibet plateau. Seismograms recorded from the moment magnitude（MW） 5.4 Minxian earthquake enable obtaining an average crustal velocity model for this region. We initially carried out a series of FWA robustness tests in regional waveform inversion at the same earthquake and station positions across the study region,inverting two velocity structure models, with and without a low-velocity crustal layer; the accuracy of our average inversion results and their standard deviations reveal the advantages of the FWA for the inversion of regional seismic waveforms. We applied the FWA across our study area using three component waveform data recorded by nine broadband permanent seismic stations with epicentral distances ranging between 146 and 437 km. These inversion results show that the average thickness of the crust in this region is 46.75 km, while thicknesses of the sedimentary layer, and the upper, middle, and lower crust are 3.15,15.69, 13.08, and 14.83 km, respectively. Results also show that the P-wave velocities of these layers and the upper mantle are 4.47, 6.07, 6.12, 6.87, and 8.18 km/s,respectively.

关键词： Seismic waveform inversion Crustal velocity structure Central Gansu Province Firework algorithm

Compositional Variability and Mutation Spectra of Monophyletic SARS-CoV-2 Clades

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Genomics, Proteomics & Bioinformatics 2020年第6期18卷 648-663页

作者： Xufei Teng Qianpeng Li Zhao Li yuansheng zhang Guangyi Niu Jingfa Xiao Jun Yu zhang zhang Shuhui Song China National Center for Bioinformation Beijing 100101China National Genomics Data Center&CAS Key Laboratory of Genome Sciences and Information Beijing Institute of GenomicsChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

COVID-19 and its causative pathogen SARS-CoV-2 have rushed the world into a staggering pandemic in a few months,and a global fight against both has been ***,we describe an analysis procedure where genome composition and its variables are related,through the genetic code to molecular mechanisms,based on understanding of RNA replication and its feedback loop from mutation to viral proteome sequence fraternity including effective sites on the replicase-transcriptase *** analysis starts with primary sequence information,identity-based phylogeny based on 22,051 SARS-CoV-2 sequences,and evaluation of sequence variation patterns as mutation spectra and its 12 permutations among organized *** are tailored to two key mechanisms:strand-biased and function-associated *** findings are listed as follows:1)The most dominant mutation is C-to-U permutation,whose abundant second-codon-position counts alter amino acid composition toward higher molecular weight and lower hydrophobicity,albeit assumed most slightly deleterious.2)The second abundance group includes three negative-strand mutations(U-to-C,A-to-G,and G-to-A)and a positive-strand mutation(G-to-U)due to DNA repair mechanisms after cellular abasic events.3)A clade-associated biased mutation trend is found attributable to elevated level of negative-sense strand synthesis.4)Within-clade permutation variation is very informative for associating non-synonymous mutations and viral proteome *** findings demand a platform where emerging mutations are mapped onto mostly subtle but fast-adjusting viral proteomes and transcriptomes,to provide biological and clinical information after logical convergence for effective pharmaceutical and diagnostic *** actions are in desperate need,especially in the middle of the War against COVID-19.

关键词： SARS-CoV-2 Nucleotide composition Mutation spectrum Viral replication

Understanding the influencing factors and evolving trends of the Yellow River Water-Sediment Regulation System from a system perspective

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Frontiers of Engineering Management 2024年第3期11卷 528-541页

作者： Zhiwei CAO yuansheng zhang Huanfa CHEN Chaoqun LI Yuan LUO Yellow River Engineering Consulting Co Ltd Zhengzhou 450000China North China University of Water Resources and Electric Power ZhengzhouChina University College London LondonUK

Understanding the influencing factors and the evolving trends of the Water-Sediment Regulation System(WSRS)is vital for the protection and management of the Yellow *** studies on WSRS have been limited in focus and have not fully addressed the complete engineering control system of the *** study takes a holistic view,treating sediment management in the Yellow River as a dynamic and ever-evolving complex *** merges concepts from system science,information theory,and dissipative structure with practical efforts in sediment engineering *** key findings of this study are as follows:between 1990 and 2019,the average Yellow River Sediment Regulation Index(YSRI)was 55.99,with the lowest being 50.26 in 1990 and the highest being 61.48 in 2019;the result indicates that the WSRS activity decreased,yet it fluctuated,gradually approaching the critical threshold of a dissipative structure.

关键词： Yellow River Water-Sediment Regulation System Yellow River Sediment Regulation Index system perspective sustainable management.

Effects of the Nepal M_S8. 1 Earthquake in 2015 on Seismic Activity in the Qinghai-Tibetan Plateau

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Earthquake Research in China 2019年第3期33卷 451-460页

作者： CHENG Guoliang zhang yuansheng WEI Congxin Lanzhou Institute of Seismology China Earthquake Administration

We obtained the displacement and deformation caused by the 2015 Nepal MS8. 1 earthquake adopting the finite element method,and analyzed the displacement and deformation characteristics and effect of three large earthquakes on seismic activity in the Qinghai-Tibetan block. Our primary results suggest southward movement of the QinghaiTibetan block is caused by a large earthquake occurring on thrust fault in the Himalayan zone,the displacement direction is reverse to the background displacement. The occurrence of these large earthquakes will result in stress unloading and earthquake activity will be weakened in stress unloading areas. Through the simulation results,we can detect the distribution area of stress loading and unloading caused by large ***,it provides a fundamental evidence for determination of earthquake activity trend.

关键词： Nepal MS8.1 earthquake Stress loading and unloading Earthquake quiescence Seismogenic region forecast

Analysis of Thermal Infrared Anomalies for the April16,2013M_W7.8of Khash, Iran Earthquake

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Earthquake Research in China 2018年第3期32卷 435-441页

作者： Wang Ying zhang yuansheng Wei Congxin Lanzhou Institute of Seismology China Earthquake Administration

After using the "Time-Frequency Relative Power Spectrum"( T-F RPS) method based on the China Geostationary Meteorological Satellite( FY-2 C/FY-2 E) infrared remote sensing brightness temperature data processing,we rapidly and accurately extracted and identified pre-earthquake thermal infrared anomalies for the April 16,2013 MW7. 8 of Khash,Iran Earthquake. Spatial evolution of anomalies showed the distribution and process. The anomalies were mainly distributed in the east of Khash,Iran. The characteristics of process and distribution presented X-Type model of NE and near NS strip which relates to the geological structure of this region. The epicenter was located near the intersection region of the X-Type abnormal migration process. Besides,the results of time series of anomalies showed that,the duration was more than 40 days and the maximum amplitude was about18 times. The earthquake occurred 20 days after the abnormal maximum amplitude which appeared on March 26,2013.

关键词： Satellite remote sensing Strong earthquake Thermal infrared brightness temperature Pre-earthquake thermal anomaly Time-Frequency spectrum

Wenchuan earthquake:Brightness temperature changes from satellite infrared information

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Chinese Science Bulletin 2010年第18期55卷 1917-1924页

作者： zhang yuansheng GUO Xiao ZHONG MeiJiao SHEN WenRong LI Wen HE Bin Lanzhou Institute of Seismology China Earthquake Administration Lanzhou 730000 China Lanzhou Base of Institute of Earthquake Prediction China Earthquake Administration Lanzhou 730000 China

By using an alternative processing method for satellite infrared remote sensing data and adopting the China Geostationary Meteorological Satellite(FY-2C) infrared remote sensing brightness temperature data,we studied the great 2008 Wenchuan Ms8.0 *** indicate the obvious characteristic period and amplitude,and distribution of thermal infrared anomalies before the Wenchuan *** we discussed the mechanism of the observed pre-earthquake thermal *** characteristics of observed thermal infrared anomalies are easy to be recognized and applied,and could provide a criterion for thermal anomalies of earthquakes.

关键词：红外信息大地震温度变化卫星汶川亮度遥感数据地球同步