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The Effect of Strong Near Surface Scattering on Seismic Imaging: Investigation Based on Resolution Analysis

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Communications in Computational Physics 2020年第6期28卷 167-186页

作者： xiao-bi xie Baoqing He Hongxiao Ning Yongqing He Bo Chen Institute of Geophysics and Planetary Physics University of California at Santa CruzCA 95064USA China National Petroleum Corp Bureau of Geophysical Prospecting Inc. Center for Acquisition TechnologyZhuozhouHebeiChina China School of Earth Science and Geological Engineering Sun Yat-Sen UniversityGuangzhouGuangdongChina

In land seismic exploration,strong near-surface heterogeneities can cause serious problems in seismic data acquisition and the quality of depth imaging.By introducing random velocity models to simulate velocity fluctuations in the near-surface layer and using the point spread function to characterize image quality,we examine how the scattering generated in near-surface heterogeneities can affect the subsurface image.In addition to the commonly known scattering noises which lower the signal to noise ratio in seismic data,our results also reveal that intermediate scale hetero-geneities generate forward scattering which forms phase or travel time fluctuations.Due to intermediate-scale uncertainty in the shallow part of the migration velocity model,these phase changes are carried to the target by the extrapolated wavefields,breaking the zero phase image condition at the image point.This is a primary reason for deteriorated image quality in regions with strong near-surface scattering.If this intermediate-scale information can be obtained and built into the migration velocity,the subsurface image quality can be largely improved.These results can be the ba-sis for further numerical investigations and field experiments.The proposed analysis method can also be used to evaluate other potential methods for dealing with near-surface scattering.

关键词： Reverse time migration shallow scattering velocity model prestack depth imaging seismic resolution

Stress drop assessment of the August 8, 2017, Jiuzhaigou earthquake sequence and its tectonic implications

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Earthquake Science 2020年第4期33卷 161-176页

作者： Xi He Lian-Feng Zhao xiao-bi xie Lin Shen Wei-Min Wang Zhen-Xing Yao Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics^Chinese Academy of SciencesBeijing 100029China Institute of Geophysics and Planetary Physics University of California at Santa CruzCA 95064USA Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

By using a broadband Lg attenuation model developed for the Tibetan Plateau,we isolate source terms by removing attenuation and site effects from the observed Lg-wave displacement spectra of the M 7.0 earthquake that occurred on August 8,2017,in Jiuzhaigou,China,and its aftershock sequence.Thus,the source parameters,including the scalar seismic moment,comer frequency and stress drop,of these events can be further estimated.The estimated stress drops vary from 47.1 kPa to 7149.6 kPa,with a median value of 59.4 kPa and most values falling between 50 kPa and 75 kPa.The estimated stress drops show significant spatial variations.Lower stress drops were mainly found close to the mainshock and on the seismogenic fault plane with large coseismic slip.In contrast,the highest stress drop was 7.1 MPa for the mainshock,and relatively large stress drops were also found for aftershocks away from the major seismogenic fault and at depths deeper than the zone with large coseismic slip.By using a statistical method,we found self-similarity among some of the aftershocks with a nearly constant stress drop.In contrast,the stress drop increased with the seismic moment for other aftershocks.The amount of stress released during earthquakes is a fundamental characteristic of the earthquake rupture process.As such,the stress drop represents a key parameter for improving our understanding of earthquake source physics.

关键词： scalar seismic moment comer frequency stress drop Lg attenuation Jiuzhaigou earthquake

Computational Experiments for Complex Social Systems:Integrated Design of Experiment System

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1175-1189页

作者： xiao Xue Xiangning Yu Deyu Zhou xiao Wang Chongke bi Shufang Wang Fei-Yue Wang College of Intelligence and Computing Tianjin UniversityTianjin 300350China School of Software Shandong UniversityJinan 250101China School of Artificial Intelligence Anhui UniversityHefei 230601China School of Geographic and Environmental Sciences Tianjin Normal UniversityTianjin 300387China Institute of Automation Chinese Academy of Sciences Beijing 100190China

Powered by advanced information industry and intelligent technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).And human factors have become crucial in the operations of complex social systems.Traditional mechanical analysis and social simulations alone are powerless for analyzing complex social systems.Against this backdrop,computational experiments have emerged as a new method for quantitative analysis of complex social systems by combining social simulation(e.g.,ABM),complexity science,and domain knowledge.However,in the process of applying computational experiments,the construction of experiment system not only considers a large number of artificial society models,but also involves a large amount of data and knowledge.As a result,how to integrate various data,model and knowledge to achieve a running experiment system has become a key challenge.This paper proposes an integrated design framework of computational experiment system,which is composed of four parts:generation of digital subject,generation of digital object,design of operation engine,and construction of experiment system.Finally,this paper outlines a typical case study of coal mine emergency management to verify the validity of the proposed framework.

关键词： artificial system operations

Clinical practice guideline for acupuncture and moxibustion: Female urinary incontinence

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Journal of Integrative Medicine 2024年第3期22卷 258-269页

作者： Chao Yang Shan-ze Wang Sheng Chen Shuo Du Guan-qun Wang Wei Guo xiao-long xie bi-hui Peng Shi-hao Du Ji-ping Zhao Department of Acupuncture and Moxibustion Dongzhimen HospitalBeijing University of Chinese MedicineBeijing 100700China Department of Acupuncture and Moxibustion Guangdong provincial hospital of Chinese MedicineGuangzhou 510120Guangdong ProvinceChina Shanghai Ninth People’s Hospital Shanghai Jiao Tong University School of MedicineShanghai 200011China Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijing 100700China

Urinary incontinence (UI) is a common problem worldwide.It has a major impact on physical and social activities and interpersonal relationships.UI is common in women,but is under-reported and undertreated.It affects the quality of life of female patients severely.Acupuncture and moxibustion have been proposed as potentially effective interventions for female UI.Hence,for the benefit of acupuncture practitioners around the world,the World Federation of Acupuncture-moxibustion Societies initiated a project to develop a clinical practice guideline (CPG) for the use of acupuncture and moxibustion to treat female UI.This CPG was developed according to the Grading of Recommendations Assessment,Development,and Evaluation (GRADE) methodology,referring to the principles of the World Health Organization Handbook for Guideline Development.During the development of the CPG,the guideline development group (GDG) played an important role.The clinical questions,recommendations and therapeutic protocols were all formulated by GDG using the modified Delphi method.This CPG contains ten recommendations about the use of acupuncture and moxibustion interventions for ten clinical questions,which include nine conditional recommendations for the intervention and one conditional recommendation for either the intervention or the comparison.This CPG also provides one protocol for conventional filiform needle therapy,two therapy protocols for deep needling stimulation on lumbosacral acupoints,and four moxibustion therapy protocols,based on the protocols presented in randomized controlled trials reviewed by the GDG.

关键词： Acupuncture Clinical practice guideline Female urinary incontinence Moxibustion GRADE

Clinical practice guideline for acupuncture and moxibustion:Allergic rhinitis

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Journal of Integrative Medicine 2024年第3期22卷 245-257页

作者： Shi-hao Du Sheng Chen Shan-ze Wang Guan-qun Wang Shuo Du Wei Guo xiao-long xie bi-hui Peng Chao Yang Ji-ping Zhao Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijing 100700China Department of Acupuncture and Moxibustion Dongzhimen HospitalBeijing University of Chinese MedicineBeijing 100700China Department of Acupuncture and Moxibustion Guangdong Provincial Hospital of Chinese MedicineGuangzhou 510120Guangdong ProvinceChina Department of Traditional Chinese Medicine Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China

Acupuncture is one of the most effective complementary therapies for allergic rhinitis(AR)and has been recommended by several clinical practice guidelines(CPGs)for AR.However,these CPGs mentioned acupuncture without making recommendations for clinical implementation and therapeutic protocols,therefore limiting the applicability of acupuncture therapies for AR.Hence,for the benefit of acupuncture practitioners around the world,the World Federation of Acupuncture-moxibustion Societies have initiated a project to develop the CPG for the use of acupuncture and moxibustion to treat AR.This CPG was developed according to the Grading of Recommendations Assessment,Development,and Evaluation(GRADE)methodology,referring to the principles of the World Health Organization Handbook for Guideline Development.During the development of the CPG,the guideline development group(GDG)played an important role.The clinical questions,recommendations and therapeutic protocols were all formulated by the GDG using the modified Delphi method.The CPG contains recommendations for 15 clinical questions about the use of acupuncture and moxibustion interventions.These include one strong recommendation for the intervention based on high-quality evidence,three conditional recommendations for either the intervention or standard care,and 11 conditional recommendations for the intervention based on very low quality of evidence.The CPG also provides one filiform needle acupuncture protocol and five moxibustion protocols extracted based on the protocols presented in randomized controlled trials reviewed by the GDG.

关键词： Clinical practice guideline Allergic rhinitis Acupuncture Moxibustion GRADE

Effect of an Airbag-selective Portal Vein Blood Arrester on the Liver after Hepatectomy:A New Technique for Selective Clamping of the Portal Vein

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Current Medical Science 2024年第2期44卷 380-390页

作者： Ce-xiong FU xiao-ri QIN Jin-song CHEN Jie ZHONG Yu-xu xie bi-dan LI Qing-qing FU Fang LI Jin-fang ZHENG Department of Hepatobiliary and Pancreatic Surgery Hainan General HospitalHainan Affiliated Hospital of Hainan Medical UniversityHaikou 57031lChina University of South China Hengyang 421001China Department of Gastroenterology Gastroenterology Endoscopy CenterHainan General HospitalHainan Affiliated Hospital of Hainan Medical UniversityHaikou 57031lChina Center of Clinical Laboratory Hainan General HospitalHainan Afiliated Hospital of Hainan Medical UniversityHaikou 570311China Department of Radiology Hainan General HospitalHainan Afiliated Hospital of Hainan Medical UniversityHaikou 570311China

Objective:A novel technique was explored using an airbag-selective portal vein blood arrester that circumvents the need for an intraoperative assessment of anatomical variations in patients with complex intrahepatic space-occupying lesions.Methods:Rabbits undergoing hepatectomy were randomly assigned to 4 groups:intermittent portal triad clamping(PTC),intermittent portal vein clamping(PVC),intermittent portal vein blocker with an airbag-selective portal vein blood arrester(APC),and without portal blood occlusion(control).Hepatic ischemia and reperfusion injury were assessed by measuring the 7-day survival rate,blood loss,liver function,hepatic pathology,hepatic inflammatory cytokine infiltration,hepatic malondialdehyde levels,and proliferating cell nuclear antigen levels.Results:Liver damage was substantially reduced in the APC and PVC groups.The APC animals exhibited transaminase levels similar to or less oxidative stress damage and inflammatory hepatocellular injury compared to those exhibited by the PVC animals.Bleeding was significantly higher in the control group than in the other groups.The APC group had less bleeding than the PVC group because of the avoidance of portal vein skeletonization during hepatectomy.Thus,more operative time was saved in the APC group than in the PVC group.Moreover,the total 7-day survival rate in the APC group was higher than that in the PTC group.Conclusion:Airbag-selective portal vein blood arresters may help protect against hepatic ischemia and reperfusion injury in rabbits undergoing partial hepatectomy.This technique may also help prevent liver damage in patients requiring hepatectomy.

关键词： hepatectomy portal vein hepatic damage selective clamping

Frequency-domain crosswell reverse time migration with up and downgoing wave separation

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Frequency-domain crosswell reverse time migration with up an...

Nicotinamide adenine dinucleotide phosphate oxidase in pancreatic diseases:Mechanisms and future perspectives

中国科学院地质与地球物理研究所2013年度（第13届）...

作者： Yike Liu Huiyi Lu Youli Ouan xiao-bi xie Institute of Geology and Geophysics Chinese Academy of Sciences Stanford University University of California at Santa Cruz

Crosswell reverse time migration(RTM) with up and downgoing wave separation can greatly reduce artifacts usually seen in the conventional RTM without wave separation.However,the up and downgoing wave separation cannot be efficiently conducted in space-time domain algorithms because the upper/lower half space images are indistinguishable.In order to tackle this problem,we propose a frequency-domain algorithm with up and downgoing wave decomposition for the crosswell RTM.The numerical experiments and field data example demonstrate that the proposed method can greatly attenuate migration artifacts while still keep reasonable efficiency.

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World Journal of Gastroenterology 2024年第5期30卷 429-439页

作者： Ya-Wei bi Long-Song Li Nan Ru Bo Zhang xiao Lei Department of Gastroenterology The First Medical Center of Chinese PLA General HospitalBeijing 100853China Department of Radiation Oncology Chinese PLA General HospitalBeijing 100853China

Pancreatitis and pancreatic cancer(PC)stand as the most worrisome ailments affecting the pancreas.Researchers have dedicated efforts to unraveling the mechanisms underlying these diseases,yet their true nature continues to elude their grasp.Within this realm,oxidative stress is often believed to play a causal and contributory role in the development of pancreatitis and PC.Excessive accumulation of reactive oxygen species(ROS)can cause oxidative stress,and the key enzyme responsible for inducing ROS production in cells is nicotinamide adenine dinucleotide phosphate hydrogen oxides(NOX).NOX contribute to pancreatic fibrosis and inflammation by generating ROS that injure acinar cells,activate pancreatic stellate cells,and mediate macrophage polarization.Excessive ROS production occurs during malignant transformation and pancreatic carcinogenesis,creating an oxidative microenvironment that can cause abnormal apoptosis,epithelial to mesenchymal transition and genomic instability.Therefore,understanding the role of NOX in pancreatic diseases contributes to a more in-depth exploration of the exact pathogenesis of these diseases.In this review,we aim to summarize the potential roles of NOX and its mechanism in pancreatic disorders,aiming to provide novel insights into understanding the mechanisms underlying these diseases.

关键词： Nicotinamide adenine dinucleotide phosphate hydrogen oxides Pancreatitis Pancreatic cancer Reactive oxygen species Mechanism

Intake of tobacco nitrosamines of smokers in various provinces of China and their cancer risk:A meta-analysis

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Journal of Environmental Sciences 2024年第7期141卷 249-260页

作者： xiao Li Zhiwei Ye Jun Wang Pengfei Lin xiaojin Zhang Shuguang xie Chao Chen Research Institute for Environmental Innovation(Suzhou) TsinghuaSuzhouJiangsu 215163China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Shenzhen Key Laboratory of Organic Pollution Prevention and Control State Key Laboratory of Urban Water Resource and EnvironmentHarbin Institute of TechnologyShenzhen 518055China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Science and EngineeringPeking UniversityBeijing 100871China

Nitrosamines are a class of carcinogens which have been detected widely in food,water,some pharmaceuticals as well as tobacco.The objectives of this paper include reviewing the basic information on tobacco consumption and nitrosamine contents,and assessing the health risks of tobacco nitrosamines exposure to Chinese smokers.We searched the publications in English from“Web of Science”and those in Chinese from the“China National Knowledge Infrastructure”in 2022 and collected 151 literatures with valid information.The content of main nitrosamines in tobacco,including 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone(NNK),N-nitrosonornicotine(NNN),N-nitrosoanatabine(NAT),N-nitrosoanabasine(NAB),total tobacco-specific nitrosamines(TSNA),and N-nitrosodimethylamine(NDMA)were summarized.The information of daily tobacco consumption of smokers in 30 provinces of China was also collected.Then,the intakes of NNN,NNK,NAT,NAB,TSNAs,and NDMA via tobacco smoke were estimated as 1534ng/day,591 ng/day,685 ng/day,81 ng/day,2543 ng/day,and 484 ng/day by adult smokers in30 provinces,respectively.The cancer risk(CR)values for NNN and NNK inhalation intake were further calculated as 1.44×10^(-5)and 1.95×10^(-4).The CR value for NDMA intake via tobacco smoke(inhalation:1.66×10^(-4))indicates that NDMA is similarly dangerous in tobacco smoke when compared with the TSNAs.In China,the CR values caused by average nitrosamines intake via various exposures and their order can be estimated as the following:smoke(3.75×10^(-4))>food(1.74×10^(-4))>drinking water(1.38×10^(-5)).Smokers in China averagely suffer 200%of extra cancer risk caused by nitrosamines in tobacco when compared with non-smokers.

关键词： N-nitrosamine Tobacco Cancer risk Tobacco specific nitrosamines(TSNAs) N-nitrosodimethylamine(NDMA)