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Predicting hepatocellular carcinoma: A new non-invasive model based on shear wave elastography 被引量:1
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作者 Dong Jiang Yi Qian +9 位作者 Yi-Jun Gu Ru Wang Hua Yu Hui Dong Dong-Yu Chen Yan Chen Hao-Zheng Jiang Bi-Bo Tan Min Peng Yi-Ran Li 《World Journal of Gastroenterology》 SCIE CAS 2024年第25期3166-3178,共13页
BACKGROUND Integrating conventional ultrasound features with 2D shear wave elastography(2D-SWE)can potentially enhance preoperative hepatocellular carcinoma(HCC)predictions.AIM To develop a 2D-SWE-based predictive mod... BACKGROUND Integrating conventional ultrasound features with 2D shear wave elastography(2D-SWE)can potentially enhance preoperative hepatocellular carcinoma(HCC)predictions.AIM To develop a 2D-SWE-based predictive model for preoperative identification of HCC.METHODS A retrospective analysis of 884 patients who underwent liver resection and pathology evaluation from February 2021 to August 2023 was conducted at the Oriental Hepatobiliary Surgery Hospital.The patients were divided into the modeling group(n=720)and the control group(n=164).The study included conventional ultrasound,2D-SWE,and preoperative laboratory tests.Multiple logistic regression was used to identify independent predictive factors for RESULTS In the modeling group analysis,maximal elasticity(Emax)of tumors and their peripheries,platelet count,cirrhosis,and blood flow were independent risk indicators for malignancies.These factors yielded an area under the curve of 0.77(95%confidence interval:0.73-0.81)with 84%sensitivity and 61%specificity.The model demonstrated good calibration in both the construction and validation cohorts,as shown by the calibration graph and Hosmer-Lemeshow test(P=0.683 and P=0.658,respectively).Additionally,the mean elasticity(Emean)of the tumor periphery was identified as a risk factor for microvascular invasion(MVI)in malignant liver tumors(P=0.003).Patients receiving antiviral treatment differed significantly in platelet count(P=0.002),Emax of tumors(P=0.033),Emean of tumors(P=0.042),Emax at tumor periphery(P<0.001),and Emean at tumor periphery(P=0.003).CONCLUSION 2D-SWE’s hardness value serves as a valuable marker for enhancing the preoperative diagnosis of malignant liver lesions,correlating significantly with MVI and antiviral treatment efficacy. 展开更多
关键词 shear wave elastography Predicting model Microvascular invasion Antiviral treatment Hepatocellular carcinoma
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Photoacoustic elastography based on laser-excited shear wave
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作者 Yang Liu Ruoyi Shi +1 位作者 Gang Li Mingjian Sun 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第3期56-72,共17页
Elastography can be used as a diagnostic method for quantitative characterization of tissue hardness information and thus,differential changes in pathophysiological states of tissues.In this study,we propose a new met... Elastography can be used as a diagnostic method for quantitative characterization of tissue hardness information and thus,differential changes in pathophysiological states of tissues.In this study,we propose a new method for shear wave elastography(SWE)based on laser-excited shear wave,called photoacoustic shear wave elastography(PASWE),which combines photoacoustic(PA)technology with ultrafast ultrasound imaging.By using a focused laser to excite shear waves and ultrafast ultrasonic imaging for detection,high-frequency excitation of shear waves and noncontact elastic imaging can be realized.The laser can stimulate the tissue with the light absorption characteristic to produce the thermal expansion,thus producing the shear wave.The frequency of shear wave induced by laser is higher and the frequency band is wider.By tracking the propagation of shear wave,Young’s modulus of tissue is reconstructed in the whole shear wave propagation region to further evaluate the elastic information of tissue.The feasibility of the method is verified by experiments.Compared with the experimental results of supersonic shear imaging(SSI),it is proved that the method can be used for quantitative elastic imaging of the phantoms.In addition,compared with the SSI method,this method can realize the noncontact excitation of the shear wave,and the frequency of the shear wave excited by the laser is higher than that of the acoustic radiation force(ARF),so the spatial resolution is higher.Compared to the traditional PA elastic imaging method,this method can obtain a larger imaging depth under the premise of ensuring the imaging resolution,and it has potential application value in the clinical diagnosis of diseases requiring noncontact quantitative elasticity. 展开更多
关键词 ELASTOGRAPHY shear wave PHOTOACOUSTIC Young's modulus
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Assessment of liquefaction potential based on shear wave velocity:Strain energy approach
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作者 Mohammad Hassan Baziar Mahdi Alibolandi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3733-3745,共13页
Liquefaction assessment based on strain energy is significantly superior to conventional stress-based methods.The main purpose of the present study is to investigate the correlation between shear wave velocity and str... Liquefaction assessment based on strain energy is significantly superior to conventional stress-based methods.The main purpose of the present study is to investigate the correlation between shear wave velocity and strain energy capacity of silty sands.The dissipated energy until liquefaction occurs was calculated by analyzing the results of three series of comprehensive cyclic direct simple shear and triaxial tests on Ottawa F65,Nevada,and Firoozkuh sands with varying silt content by weight and relative densities.Additionally,the shear wave velocity of each series was obtained using bender element or resonant column tests.Consequently,for the first time,a liquefaction triggering criterion,relating to effective overburden normalized liquefaction capacity energy(WL=s’c)to effective overburden stresscorrected shear wave velocity(eVs1)has been introduced.The accuracy of the proposed criteria was evaluated using in situ data.The results confirm the ability of shear wave velocity as a distinguishing parameter for separating liquefied and non-liquefied soils when it is calculated against liquefaction capacity energy(WL=s’c).However,the proposed WL=s’c-Vs1 curve,similar to previously proposed cyclic resistance ratio(CRR)-Vs1 relationships,should be used conservatively for fields vulnerable to liquefaction-induced lateral spreading. 展开更多
关键词 LIQUEFACTION Strain energy capacity shear wave velocity Cyclic triaxial test Cyclic direct simple shear test Resonant column test Bender element test
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Shear wave velocity model using HVSR inversion beneath Bandar Lampung City
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作者 Ahmad Zaenudin Alhada Farduwin +1 位作者 Gede I Boy Darmawan Karyanto 《Earthquake Science》 2024年第4期337-351,共15页
The horizontal-to-vertical spectral ratio(HVSR)method has been used to characterize site-effect parameters that are indispensable in seismic hazard and risk-reduction studies in urban areas and rapid land-use planning... The horizontal-to-vertical spectral ratio(HVSR)method has been used to characterize site-effect parameters that are indispensable in seismic hazard and risk-reduction studies in urban areas and rapid land-use planning.This method is widely used because it is the cheapest and simplest geophysical method for the acquisition and processing stages.In subsequent developments,the HVSR method has been widely used to determine elastic rock parameters,particularly shear wave velocity(v_(S)),through the HVSR curve inversion process.Furthermore,the v_(S)structural model can be used to delineate the presence of complex geological structures,particularly faults and sedimentary basins.Bandar Lampung is a city in Lampung Province with many fault structures and groundwater basins to the south.There are 83 HVSR measurement points around Bandar Lampung for delineating the presence of fault structures and groundwater basins.We produced the HVSR curve from the measurement results and then performed an inversion process using the particle swarm optimization algorithm to obtain v_(S)for the depth profile.Subsequently,from this profile,we produced a two-dimensional(2D)lateral and vertical model.The mean v_(S)value was calculated from all the measurement points,and we found stiff soil layers reaching depths of approximately 5 m,with a value of v_(S)<330 m/s.A bedrock layer with a velocity exceeding 1250 m/s was visible at a depth of 100 m.Based on the 2D model,the v_(S)structure shows that the city of Bandar Lampung is divided into two zones,with a NW-SE boundary.The north-middle-eastern part of the city consists of harder rocks.This harder rock is characterized by extremely high v_(S)values,starting from a depth of 50 m.In contrast,the south-middle-west exhibits a low-moderate v_(S)anomaly associated with groundwater basins SW of the city.From the 2D v_(S)structural model,fault structures can be found along the city,characterized by a contrast of v_(S)values from low to medium and from medium to high. 展开更多
关键词 shear wave velocity HVSR fault structures groundwater basin Bandar Lampung City
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In vivo imaging and computational modeling of nonlinear shear waves in living skeletal muscles
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作者 Yuxi Cao Chunpeng Chai 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第4期249-258,共10页
How the state of living muscles modulates the features of nonlinear elastic waves generated by external dynamic loads remains unclear because of the challenge of directly observing and modeling nonlinear elastic waves... How the state of living muscles modulates the features of nonlinear elastic waves generated by external dynamic loads remains unclear because of the challenge of directly observing and modeling nonlinear elastic waves in skeletal muscles in vivo,considering their active deformation behavior.Here,this important issue is addressed by combining experiments performed with an ultrafast ultrasound imaging system to track nonlinear shear waves(shear shock waves)in muscles in vivo and finite element analysis relying on a physically motivated constitutive model to study the effect of muscle activation level.Skeletal muscle was loaded with a deep muscle stimulator to generate shear shock waves(SSWs).The particle velocities,second and third harmonics,and group velocities of the SSWs in living muscles under both passive and active states were measured in vivo.Our experimental results reveal,for the first time,that muscle states have a pronounced effect on wave features;a low level of activation may facilitate the occurrence of both the second and third harmonics,whereas a high level of activation may inhibit the third harmonic.Finite element analysis was further carried out to quantitatively explore the effect of active muscle deformation behavior on the generation and propagation of SSWs.The simulation results at different muscle activation levels confirmed the experimental findings.The ability to reveal the effects of muscle state on the features of SSWs may be helpful in elucidating the unique dynamic deformation mechanism of living skeletal muscles,quantitatively characterizing diverse shock wave-based therapy instruments,and guiding the design of muscle-mimicking soft materials. 展开更多
关键词 Imaging nonlinear shear waves in living skeletal muscles Finite element modeling Ultrafast ultrasound imaging system In vivo measurement
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Seismic anisotropy and upper mantle dynamics in Alaska:A review of shear wave splitting analyses
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作者 Zhaofeng Jin Yuchen Yang +7 位作者 Muhammad Ishaidir Siregar Zihao Mu S.M.Ariful Islam Qichao Zhao Dan Wang Fan Zhang Xugang Yang Liwei Song 《Earthquake Research Advances》 CSCD 2024年第2期72-81,共10页
Shear wave splitting(SWS)is regarded as the most effective geophysical method to delineate mantle flow fields by detecting seismic azimuthal anisotropy in the earth's upper mantle,especially in tectonically active... Shear wave splitting(SWS)is regarded as the most effective geophysical method to delineate mantle flow fields by detecting seismic azimuthal anisotropy in the earth's upper mantle,especially in tectonically active regions such as subduction zones.The Aleutian-Alaska subduction zone has a convergence rate of approximately 50 mm/yr,with a trench length reaching nearly 2800 km.Such a long subduction zone has led to intensive continental deformation and numerous strong earthquakes in southern and central Alaska,while northern Alaska is relatively inactive.The sharp contrast makes Alaska a favorable locale to investigate the impact of subduction on mantle dynamics.Moreover,the uniqueness of this subduction zone,including the unusual subducting type,varying slab geometry,and atypical magmatic activity and composition,has intrigued the curiosity of many geoscientists.To identify different sources of seismic anisotropy beneath the Alaska region and probe the influence of a geometrically varying subducting slab on mantle dynamics,extensive SWS analyses have been conducted in the past decades.However,the insufficient station and azimuthal coverage,especially in early studies,not only led to some conflicting results but also strongly limited the in-depth investigation of layered anisotropy and the estimation of anisotropy depth.With the completion of the Transportable Array project in Alaska,recent studies have revealed more detailed mantle structures and characteristics based on the dense station coverage and newly collected massive seismic data.In this study,we review significant regional-and continental-scale SWS studies in the Alaska region and conclude the mantle flow fields therein,to understand how a geometrically varying subducting slab alters the regional mantle dynamics.The summarized mantle flow mechanisms are believed to be conducive to the understanding of seismic anisotropy patterns in other subduction zones with a complicated tectonic setting. 展开更多
关键词 Seismic anisotropy shear wave splitting Mantle flow Alaska subduction zone SLAB
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Application of real-time shear wave elastography to Achilles tendon hardness evaluation in older adults
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作者 Xuan He Xin Wei +2 位作者 Jia Hou Wei Tan Ping Luo 《World Journal of Clinical Cases》 SCIE 2024年第26期5922-5929,共8页
BACKGROUND Real-time shear wave elastography(SWE)is a non-invasive imaging technique used to measure tissue stiffness by generating and tracking shear waves in real time.This advanced ultrasound-based method provides ... BACKGROUND Real-time shear wave elastography(SWE)is a non-invasive imaging technique used to measure tissue stiffness by generating and tracking shear waves in real time.This advanced ultrasound-based method provides quantitative information regarding tissue elasticity,offering valuable insights into the mechanical properties of biological tissues.However,the application of real-time SWE in the musculoskeletal system and sports medicine has not been extensively studied.AIM To explore the practical value of real-time SWE for assessing Achilles tendon hardness in older adults.METHODS A total of 60 participants were enrolled in the present study,and differences in the elastic moduli of the bilateral Achilles tendons were compared among the following categories:(1)Age:55-60,60-65,and 65-70-years-old;(2)Sex:Male and female;(3)Laterality:Left and right sides;(4)Tendon state:Relaxed and tense state;and(5)Tendon segment:Proximal,middle,and distal.RESULTS There were no significant differences in the elastic moduli of the bilateral Achilles tendons when comparing by age or sex(P>0.05).There were,however,significant differences when comparing by tendon side,state,or segment(P<0.05).CONCLUSION Real-time SWE plays a significant role compared to other examination methods in the evaluation of Achilles tendon hardness in older adults. 展开更多
关键词 Aged Achilles tendon REAL-TIME shear wave elastography Young’s modulus Muscle stiffness
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Shear wave velocity prediction:A review of recent progress and future opportunities
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作者 John Oluwadamilola Olutoki Jian-guo Zhao +5 位作者 Numair Ahmed Siddiqui Mohamed Elsaadany AKM Eahsanul Haque Oluwaseun Daniel Akinyemi Amany H.Said Zhaoyang Zhao 《Energy Geoscience》 EI 2024年第4期36-54,共19页
Shear logs,also known as shear velocity logs,are used for various types of seismic analysis,such as determining the relationship between amplitude variation with offset(AVO)and interpreting multiple types of seismic d... Shear logs,also known as shear velocity logs,are used for various types of seismic analysis,such as determining the relationship between amplitude variation with offset(AVO)and interpreting multiple types of seismic data.This log is an important tool for analyzing the properties of rocks and interpreting seismic data to identify potential areas of oil and gas reserves.However,these logs are often not collected due to cost constraints or poor borehole conditions possibly leading to poor data quality,though there are various approaches in practice for estimating shear wave velocity.In this study,a detailed review of the recent advances in the various techniques used to measure shear wave(S-wave)velocity is carried out.These techniques include direct and indirect measurement,determination of empirical relationships between S-wave velocity and other parameters,machine learning,and rock physics models.Therefore,this study creates a collection of employed techniques,enhancing the existing knowledge of this significant topic and offering a progressive approach for practical implementation in the field. 展开更多
关键词 shear wave(S-wave)velocity Direct and indirect measurement Empirical relationship Artificial intelligence(AI) Machine learning Rock physics model
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Does shear wave elastography technology provide better value for the assessment of perianal fistulizing Crohn’s disease?
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作者 Jiong Wu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第11期3636-3638,共3页
Magnetic resonance imaging is the gold standard compared other clinical fin-dings.But shear wave elastography technique combined with endoscopic ultra-sound can evaluate the degree of fibrosis of fistula tissue in Cr... Magnetic resonance imaging is the gold standard compared other clinical fin-dings.But shear wave elastography technique combined with endoscopic ultra-sound can evaluate the degree of fibrosis of fistula tissue in Crohn’s disease patients.This topic is highly relevant to the current discourse,especially for It shows a certain degree of innovation and practicality and is worthy of study and popularization. 展开更多
关键词 Perianal fistulizing Crohn’s disease shear wave elastography ULTRASOUND Magnetic resonance imaging
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The characteristics of shear wave splitting in the source region of the April 20,2013 Lushan earthquake 被引量:2
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作者 Sha Liu Jiansi Yang +3 位作者 Baofeng Tian Yu Zheng Xudong Jiang Zhiqiang Xu 《Earthquake Science》 2013年第3期223-228,共6页
Using seismic data of the aftershocks sequence of the April 20, 2013 Lushan earthquake recorded by seismic temporary and permanent stations in the source region, with the visual inspection of particle motion diagrams,... Using seismic data of the aftershocks sequence of the April 20, 2013 Lushan earthquake recorded by seismic temporary and permanent stations in the source region, with the visual inspection of particle motion diagrams, this paper preliminarily contains the polarization directions of fast shear wave and the time-delays of split shear waves at every station, and analyzes the crustal anisotropic characteristics in the source region. In the study area, the polarization direc- tions at stations BAX, TQU, L 132, L 133, L 134, and L 135 are northeast, which is consistent with the strike of Dachuan- Shuangshi fault. There are two polarization directions at MDS and L131, which are northeast and southeast. The scatter of polarization directions suggests the complex stress field around these two stations where two faults intersect. For the normalized time-delays at every station, the range is 1.02-8.64 ms/km. The largest time-delay is from L134 which is closest to the mainshock, and the smallest one is from L133. The variations in time-delays show the decreasing at stations BAX, L134, and L135 because of the stress-relaxation after earthquake. 展开更多
关键词 Lushan earthquake shear wavesplitting Polarization direction of fast shear wave Time-delay of split shear wave
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Shear wave splitting analysis of local earthquakes from dense arrays in Shimian,Sichuan 被引量:2
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作者 Sha Liu Baofeng Tian 《Earthquake Science》 2023年第1期52-63,共12页
The Shimian area of Sichuan sits at the junction of the Bayan Har block.Sichuan-Yunnan rhombic block,and Yangtze block,where several faults intersect.This region features intense tectonic activity and frequent earthqu... The Shimian area of Sichuan sits at the junction of the Bayan Har block.Sichuan-Yunnan rhombic block,and Yangtze block,where several faults intersect.This region features intense tectonic activity and frequent earthquakes.In this study,we used local seismic waveform data recorded using dense arrays deployed in the Shimian area to obtain the shear wave splitting parameters at 55 seismic stations and thereby determine the crustal anisotropic characteristics of the region.We then analyzed the crustal stress pattern and tectonic setting and explored their relationship in the study area.Although some stations returned a polarization direction of NNW-SSE.a dominant polarization direction of NW-SE was obtained for the fast shear wave at most seismic stations in the study area.The polarization directions of the fast shear wave were highly consistent throughout the study-area.This orientation was in accordance with the direction of the regional principal compressive stress and parallel to the trend of the Xianshuihe and Daliangshan faults.The distribution of crustal anisotropy in this area was affected by the regional tectonic stress field and the fault structures.The mean delay time between fast and slow shear waves was 3.83 ms/km.slightly greater than the values obtained in other regions of Sichuan.This indicates that the crustal media in our study area had a high anisotropic strength and also reveals the influence of tectonic complexity resulting from the intersection of multiple faults on the strength of seismic anisotropy. 展开更多
关键词 shear wave splitting polarization direction of the fast shear wave regional principal compressive stress dense array Citation:Liu S and Tian BF(2023).shear wave splitting analysis of local earthquakes from dense arrays in Shimian Sichuan.
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Shear wave velocity prediction during CO_2-EOR and sequestration in the Gao89 well block of the Shengli Oilfield 被引量:2
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作者 李琳 马劲风 +4 位作者 王浩璠 谭明友 崔世凌 张云银 曲志鹏 《Applied Geophysics》 SCIE CSCD 2017年第3期372-380,460,共10页
Shear-wave velocity is a key parameter for calibrating monitoring time-lapse 4D seismic data during CO2-EOR (Enhanced Oil Recovery) and CO2 sequestration. However, actual S-wave velocity data are lacking, especially... Shear-wave velocity is a key parameter for calibrating monitoring time-lapse 4D seismic data during CO2-EOR (Enhanced Oil Recovery) and CO2 sequestration. However, actual S-wave velocity data are lacking, especially in 4D data for CO2 sequestration because wells are closed after the CO2 injection and seismic monitoring is continued but no well log data are acquired. When CO2 is injected into a reservoir, the pressure and saturation of the reservoirs change as well as the elastic parameters of the reservoir rocks. We propose a method to predict the S-wave velocity in reservoirs at different pressures and porosities based on the Hertz-Mindlin and Gassmann equations. Because the coordination number is unknown in the Hertz Mindlin equation, we propose a new method to predict it. Thus, we use data at different CO2 injection stages in the Gao89 well block, Shengli Oilfield. First, the sand and mud beds are separated based on the structural characteristics of the thin sand beds and then the S-wave velocity as a function of reservoir pressure and porosity is calculated. Finally, synthetic seismic seismograms are generated based on the predicted P- and S-wave velocities at different stages of CO2 injection. 展开更多
关键词 coordination number bulk modulus shear modulus Hertz-Mindlin shear wave CO2-EOR
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Shear Wave Elastography of Invasive Ductal Carcinoma:Correlations between Shear Wave Velocity and Histological Prognostic Factors 被引量:1
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作者 Xiao-qing HU Li PENG +3 位作者 Max Wintermark Jafi Alyssa Lipson Yan-rong ZHANG Yuan GAO 《Current Medical Science》 SCIE CAS 2021年第1期173-179,共7页
The correlations between shear wave velocity(SWV)calculated from virtual touch tissue imaging quantification(VTIQ)technique and histological prognostic factors of invasive ductal carcinoma was investigated.A total of ... The correlations between shear wave velocity(SWV)calculated from virtual touch tissue imaging quantification(VTIQ)technique and histological prognostic factors of invasive ductal carcinoma was investigated.A total of 76 breast tumors histologically confirmed as invasive ductal carcinomas were included in this study.SWV values were measured by VTIQ for each lesion preoperatively or prior to breast biopsy.The maximum values were recorded for statistical analysis.Medical records were reviewed to determine tumor size,histological grade,lymph node status and immunohistochemical results.Tumor subtypes were categorized as luminal A,luminal B,human epidermal growth factor receptor 2(HER2)positive and triple negative.The correlations between SWV and histological prognostic factors were analyzed.It was found that tumor size showed positive association with SWV(r=0.465,P<0.001).Larger tumors had significantly higher SWV than smaller ones(P=0.001).Histological grade 1 tumors had significantly lower SWV values than those with higher histological grade(P=0.015).The Ki67 expression,tumor subtypes and lymph node status showed no statistically significant correlations with SWV,although triple negative tumors and lymph node-positive tumors showed higher SWV values.It was concluded that tumor size was significantly associated with SWV.Higher histological grade was associated with increased SWV.There was no statistically significant correlations between SWV and other histological prognostic factors. 展开更多
关键词 shear wave elastography virtual touch tissue imaging quantification shear wave velocity invasive ductal carcinoma histological prognostic factors
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Three dimensional shear wave velocity structure of crust and upper mantle in South China Sea and its adjacent regions by surface waveform inversion 被引量:22
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作者 曹小林 朱介寿 +2 位作者 赵连锋 曹家敏 洪学海 《地震学报》 CSCD 北大核心 2001年第2期113-124,共12页
We assembled approximately 328 seismic records. The data set was from 4 digitally recording long-period and broadband stations of CDSN. We carried out the inversion based on the partitioned waveform inversion (PWI). I... We assembled approximately 328 seismic records. The data set was from 4 digitally recording long-period and broadband stations of CDSN. We carried out the inversion based on the partitioned waveform inversion (PWI). It partitions the large-scale optimization problem into a number of independent small-scale problems. We adopted surface waveform inversion with an equal block (2((2() discretization in order to acquire the images of shear velocity structure at different depths (from surface to 430 km) in the crust and upper-mantle. The resolution of all these anomalies has been established with (check-board( resolution tests. These results show significant difference in velocity, lithosphere and asthenosphere structure between South China Sea and its adjacent regions. 展开更多
关键词 面波波形 分块波形反演 三维S波速度结构 中国数字地震台网 “检验板”法 岩石圈
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Shear wave velocity is a useful marker for managing nonalcoholic steatohepatitis 被引量:31
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作者 Akihiko Osaki Tomoyuki Kubota +11 位作者 Takeshi Suda Masato Igarashi Keisuke Nagasaki Atsunori Tsuchiya Masahiko Yano Yasushi Tamura Masaaki Takamura Hirokazu Kawai Satoshi Yamagiwa Toru Kikuchi Minoru Nomoto Yutaka Aoyagi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第23期2918-2925,共8页
AIM:To investigate whether a noninvasive measurement of tissue strain has a potential usefulness for management of nonalcoholic steatohepatitis(NASH).METHODS:In total 26 patients,23 NASHs and 3 normal controls were en... AIM:To investigate whether a noninvasive measurement of tissue strain has a potential usefulness for management of nonalcoholic steatohepatitis(NASH).METHODS:In total 26 patients,23 NASHs and 3 normal controls were enrolled in this study.NASH was staged based on Brunt criterion.At a region of interest(ROI),a shear wave was evoked by implementing an acoustic radiation force impulse(ARFI),and the propagation velocity was quantif ied.RESULTS:Shear wave velocity(SWV) could be reproducibly quantified at all ROIs in all subjects except for 4 NASH cases,in which a reliable SWV value was not calculated at several ROIs.An average SWV of 1.34 ± 0.26 m/s in fibrous stage 0-1 was significantly slower than 2.20 ± 0.74 m/s and 2.90 ± 1.01 m/s in stages 3 and 4,respectively,but was not significantly different from 1.79 ± 0.78 m/s in stage 2.When a cutoff value was set at 1.47 m/s,receiver operating characteristic analysis showed significance to dissociate stages 3 and 4 from stage 0-1(P=0.0092) with sensitivity,specificity and area under curve of 100%,75% and 94.2%,respectively.In addition,the correlation between SWV and hyaluronic acid was significant(P<0.0001),while a tendency toward negative correlation was observed with serum albumin(P=0.053).CONCLUSION:The clinical implementation of ARFI provides noninvasive repeated evaluations of liver stiffness at an arbitrary position,which has the potential to shed new light on NASH management. 展开更多
关键词 Nonalcoholic steatohepatitis ULTRASOUND Liver stiffness measurement shear wave velocity Acoustic radiation force impulse
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Shear wave velocity-based liquefaction evaluation in the great Wenchuan earthquake: a preliminary case study 被引量:9
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作者 Zhou Yanguo,Chen Yunmin and Ling Daosheng MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering,Institute of Geotechnical Engineering,Zhejiang University,Hangzhou 310058,China Assistant Professor Professor 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第2期231-239,共9页
The great Wenchuan earthquake (Ms= 8.0) in 2008 caused severe damage in the western part of the Chengdu Plain. Soil liquefaction was one of the major causes of damage in the plain areas, and proper evaluation of liq... The great Wenchuan earthquake (Ms= 8.0) in 2008 caused severe damage in the western part of the Chengdu Plain. Soil liquefaction was one of the major causes of damage in the plain areas, and proper evaluation of liquefaction potential is important in the definition of the seismic hazard facing a given region and post-earthquake reconstruction. In this paper, a simplified procedure is proposed for liquefaction assessment of sandy deposits using shear wave velocity (V), and soil liquefaction from the Banqiao School site was preliminarily investigated after the earthquake. Boreholes were made at the site and shear wave velocities were measured both by SASW and down-hole methods. Based on the in-situ soil information and V profiles, the liquefaction potential of this site was evaluated. The results are reasonably consistent with the actual field behavior observed after the earthquake, indicating that the proposed procedure is effective. The possible effects of gravel and fines contents on liquefaction of sandy soils were also briefly discussed. 展开更多
关键词 LIQUEFACTION Wenchuan earthquake shear wave velocity spectral analysis of surface waves (SASW) hazarddefinition
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Shear wave velocity-based evaluation and design of stone column improved ground for liquefaction mitigation 被引量:7
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作者 Zhou Yanguo Sun Zhengbo +2 位作者 Chen Jie Chen Yunmin Chen Renpeng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2017年第2期247-261,共15页
The evaluation and design of stone column improvement ground for liquefaction mitigation is a challenging issue for the state of practice. In this paper, a shear wave velocity-based approach is proposed based on the w... The evaluation and design of stone column improvement ground for liquefaction mitigation is a challenging issue for the state of practice. In this paper, a shear wave velocity-based approach is proposed based on the well-defined correlations of liquefaction resistance (CRR)-shear wave velocity (V)-void ratio (e) of sandy soils, and the values of parameters in this approach are recommended for preliminary design purpose when site specific values are not available. The detailed procedures of pre- and post-improvement liquefaction evaluations and stone column design are given. According to this approach, the required level of ground improvement will be met once the target V of soil is raised high enough (i.e., no less than the critical velocity) to resist the given earthquake loading according to the CRR-V relationship, and then this requirement is transferred to the control of target void ratio (i.e., the critical e) according to the V-e relationship. As this approach relies on the densification of the surrounding soil instead of the whole improved ground and is conservative by nature, specific considerations of the densification mechanism and effect are given, and the effects of drainage and reinforcement of stone columns are also discussed. A case study of a thermal power plant in Indonesia is introduced, where the effectiveness of stone column improved ground was evaluated by the proposed V-based method and compared with the SPT-based evaluation. This improved ground performed well and experienced no liquefaction during subsequent strong earthquakes. 展开更多
关键词 Liquefaction mitigation Stone column shear wave velocity Void ratio DENSIFICATION Ageing effect
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Non-invasive assessment of liver fibrosis using twodimensional shear wave elastography in patients with autoimmune liver diseases 被引量:8
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作者 Jie Zeng Ze-Ping Huang +2 位作者 Jian Zheng Tao Wu Rong-Qin Zheng 《World Journal of Gastroenterology》 SCIE CAS 2017年第26期4839-4846,共8页
AIM To determine the diagnostic accuracy of two-dimensional shear wave elastography(2D-SWE) for the noninvasive assessment of liver fibrosis in patients with autoimmune liver diseases(AILD) using liver biopsy as the r... AIM To determine the diagnostic accuracy of two-dimensional shear wave elastography(2D-SWE) for the noninvasive assessment of liver fibrosis in patients with autoimmune liver diseases(AILD) using liver biopsy as the reference standard.METHODS Patients with AILD who underwent liver biopsy and 2D-SWE were consecutively enrolled. Receiver operating characteristic(ROC) curves were constructed to assess the overall accuracy and to identify optimal cut-off values.RESULTS The characteristics of the diagnostic performance were determined for 114 patients with AILD. The areas under the ROC curves for significant fibrosis, severe fibrosis, and cirrhosis were 0.85, 0.85, and 0.86, respectively, and the optimal cut-off values associated with significant fibrosis(≥ F2), severe fibrosis(≥ F3), and cirrhosis(F4) were 9.7 k Pa, 13.2 k Pa and 16.3 k Pa, respectively. 2D-SWE showed sensitivity values of 81.7% for significant fibrosis, 83.0% for severe fibrosis,and 87.0% for cirrhosis, and the respective specificity values were 81.3%, 74.6%, and 80.2%. The overall concordance rate of the liver stiffness measurements obtained using 2D-SWE vs fibrosis stages was 53.5%.CONCLUSION2D-SWE showed promising diagnostic performance for assessing liver fibrosis stages and exhibited high cut-off values in patients with AILD. Low overall concordance rate was observed in the liver stiffness measurements obtained using 2D-SWE vs fibrosis stages. 展开更多
关键词 Autoimmune liver disease Liver fibrosis Two-dimensional shear wave elastography ULTRASOUND Liver stiffness
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Shear wave elastography results correlate with liver fibrosis histology and liver function reserve 被引量:7
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作者 Yan-Hong Feng Xiang-Dong Hu +6 位作者 Lin Zhai Ji-Bin Liu Lan-Yan Qiu Yuan Zu Si Liang Yu Gui Lin-Xue Qian 《World Journal of Gastroenterology》 SCIE CAS 2016年第17期4338-4344,共7页
AIM: To evaluate the correlation of shear wave elastography (SWE) results with liver fibrosis histology and quantitative function reserve. METHODS: Weekly subcutaneous injection of 60% carbon tetrachloride (1.5 mL/kg)... AIM: To evaluate the correlation of shear wave elastography (SWE) results with liver fibrosis histology and quantitative function reserve. METHODS: Weekly subcutaneous injection of 60% carbon tetrachloride (1.5 mL/kg) was given to 12 canines for 24 wk to induce experimental liver fibrosis, with olive oil given to 2 control canines. At 24 wk, liver condition was evaluated using clinical biochemistry assays, SWE imaging, lidocaine metabolite monoethylglycine-xylidide (MEGX) test, and histologic fibrosis grading. Clinical biochemistry assays were performed at the institutional central laboratory for routine liver function evaluation. Liver stiffness was measured in triplicate from three different intercostal spaces and expressed as mean liver stiffness modulus (LSM). Plasma concentrations of lidocaine and its metabolite MEGX were determined using high-performance liquid chromatography repeated in duplicate. Liver biopsy samples were fixed in 10% formaldehyde, and liver fibrosis was graded using the modified histological activity index Knodell score (F0-F4). Correlations among histologic grading, LSM, and MEGX measures were analyzed with the Pearson linear correlation coefficient. RESULTS: At 24 wk liver fibrosis histologic grading was as follows: F0, n = 2 (control); F1, n = 0; F2, n = 3; F3, n = 7; and F4, n = 2. SWE LSM was positively correlated with histologic grading (r = 0.835, P < 0.001). Specifically, the F4 group had a significantly higher elastic modulus than the F3, F2, and F0 groups (P = 0.002, P = 0.003, and P = 0.006, respectively), and the F3 group also had a significantly higher modulus than the control F0 group (P = 0.039). LSM was negatively associated with plasma MEGX concentrations at 30 min (r = -0.642; P = 0.013) and 60 min (r = -0.651; P = 0.012), time to 1/2 of the maximum concentration (r = -0.538; P = 0.047), and the area under the curve (r = -0.636; P = 0.014). Multiple comparisons showed identical differences in these three measures: significantly lower with F4 (P = 0.037) and F3 (P = 0.032) as compared to F0 and significantly lower with F4 as compared to F2 (P = 0.032). CONCLUSION: SWE LSM shows a good correlation with histologic fibrosis grading and pharmacologic quantitative liver function reserve in experimental severe fibrosis and cirrhosis. 展开更多
关键词 Liver fibrosis Histologic grading shear wave elastography Monoethylglycinexylidide test Experimental study
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Ultrasound shear wave elastography and liver fibrosis: A Prospective Multicenter Study 被引量:17
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作者 Joyce Anyona Sande Suleman Verjee +2 位作者 Sudhir Vinayak Farin Amersi Munir Ghesani 《World Journal of Hepatology》 CAS 2017年第1期38-47,共10页
AIM To assess the accuracy of shear wave elastography(SWE) alone and in combination with aminotransferase platelet ratio index(APRI) score in the staging of liver fibrosis.METHODS A multicenter prospective study was c... AIM To assess the accuracy of shear wave elastography(SWE) alone and in combination with aminotransferase platelet ratio index(APRI) score in the staging of liver fibrosis.METHODS A multicenter prospective study was conducted to assess the accuracy of SWE(medians) and APRI to predict biopsy results. The analysis focused on distinguishing the different stages of liver disease, namely, F0 from F1-4, F0-1 from F2-4, F0-2 from F3-4 and F0-3 from F4; F0-F1 from F2-F4 being of primary interest. The area under the receiver operating characteristic(AUROC) curve was computed using logistic regression model. The role of age, gender and steatosis was also assessed.RESULTS SWE alone accurately distinguished F0-1 from F2-4 with a high probability. The AUROC using SWE alone was 0.91 compared to 0.78 for using the APRI score alone.The APRI score, when used in conjunction with SWE, did not make a significant contribution to the AUROC. SWE and steatosis were the only significant predictors that differentiated F0-1 from F2-4 with an AUROC of 0.944.CONCLUSION Our study validates the use of SWE in the diagnosis and staging of liver fibrosis. Furthermore, the probability of a correct diagnosis is significantly enhanced with the addition of steatosis as a prognostic factor. 展开更多
关键词 shear wave elastography Aminotransferase platelet ration Liver fibrosis Liver biopsy
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