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Role of Vickers Ligament in the Pathogenesis of Madelung Deformity
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作者 Ge XIONG Wei ZHENG Li-hua GONG 《Current Medical Science》 SCIE CAS 2024年第4期735-740,共6页
Objective The Vickers ligament is thought to hinder the growth of palmar ulnar radius by tethering the lunate to the radius,leading to Madelung deformity.The purpose of this study was to clarify the nature of the Vick... Objective The Vickers ligament is thought to hinder the growth of palmar ulnar radius by tethering the lunate to the radius,leading to Madelung deformity.The purpose of this study was to clarify the nature of the Vickers ligament and investigate its pathogenesis in Madelung deformities based on our observation of the Vickers ligament.Methods All 22 patients(33 wrists)with Madelung deformities treated surgically between 2018 and 2022 were included.The diagnosis was confirmed radiographically in all patients.The three-dimensional computed tomography(3D-CT)data of 16 patients(19 wrists)were available.Magnetic resonance imaging(MRI)data were available for 9 patients(14 wrists).Wrist arthroscopy was used in 4 patients.The Vickers ligament was resected and submitted for histopathological examination in 8 patients.Radiographic outcomes,3D-CT,MRI,arthroscopy,surgical findings,and histopathology of the Vickers ligament were evaluated.Results The 3D-CT revealed that the Vickers ligament originated in the metaphysis and formed a metaphyseal defect at the palmar ulnar radius.In the sequential MR coronal images,the Vickers ligament could be divided into 3 branches,extending to the lunate,triquetrum and ulnar styloid.Arthroscopy and surgical findings revealed that the nature of the Vickers ligament was the stretched palmar ligament of the wrist.The histopathology results revealed ligamentous tissue and fibrocartilaginous metaplasia with a structure similar to that of the triangular fibrocartilage complex(TFCC).Conclusions The Vickers ligament is not a separate aberrant ligament.The nature of the Vickers ligament is a combination of the stretched TFCC ligament(palmar radioulnar ligament,ulnotriquetral ligament and ulnolunate ligament)and radiolunate ligament.The possible pathogenesis of Madelung deformity might be focal early epiphyseal closure at the middle part of the sigmoid notch,which leads to focal growth retardation of the radius and pulls palmar ligaments proximally to form the Vickers ligament. 展开更多
关键词 Vickers ligament madelung deformity PATHOGENEsIs computed tomography magnetic resonance imaging
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Topology Optimization of Metamaterial Microstructures for Negative Poisson’s Ratio under Large Deformation Using a Gradient-Free Method
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作者 Weida Wu Yiqiang Wang +1 位作者 Zhonghao Gao Pai Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期2001-2026,共26页
Negative Poisson’s ratio(NPR)metamaterials are attractive for their unique mechanical behaviors and potential applications in deformation control and energy absorption.However,when subjected to significant stretching... Negative Poisson’s ratio(NPR)metamaterials are attractive for their unique mechanical behaviors and potential applications in deformation control and energy absorption.However,when subjected to significant stretching,NPR metamaterials designed under small strain assumption may experience a rapid degradation in NPR performance.To address this issue,this study aims to design metamaterials maintaining a targeted NPR under large deformation by taking advantage of the geometry nonlinearity mechanism.A representative periodic unit cell is modeled considering geometry nonlinearity,and its topology is designed using a gradient-free method.The unit cell microstructural topologies are described with the material-field series-expansion(MFSE)method.The MFSE method assumes spatial correlation of the material distribution,which greatly reduces the number of required design variables.To conveniently design metamaterials with desired NPR under large deformation,we propose a two-stage gradient-free metamaterial topology optimization method,which fully takes advantage of the dimension reduction benefits of the MFSE method and the Kriging surrogate model technique.Initially,we use homogenization to find a preliminary NPR design under a small deformation assumption.In the second stage,we begin with this preliminary design and minimize deviations in NPR from a targeted value under large deformation.Using this strategy and solution technique,we successfully obtain a group of NPR metamaterials that can sustain different desired NPRs in the range of[−0.8,−0.1]under uniaxial stretching up to 20% strain.Furthermore,typical microstructure designs are fabricated and tested through experiments.The experimental results show good consistency with our numerical results,demonstrating the effectiveness of the present gradientfree NPR metamaterial design strategy. 展开更多
关键词 Topology optimization microstructural design negative Poisson’s ratio large deformation
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GAN-DIRNet:A Novel Deformable Image Registration Approach for Multimodal Histological Images
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作者 Haiyue Li Jing Xie +4 位作者 Jing Ke Ye Yuan Xiaoyong Pan Hongyi Xin Hongbin Shen 《Computers, Materials & Continua》 SCIE EI 2024年第7期487-506,共20页
Multi-modal histological image registration tasks pose significant challenges due to tissue staining operations causing partial loss and folding of tissue.Convolutional neural network(CNN)and generative adversarial ne... Multi-modal histological image registration tasks pose significant challenges due to tissue staining operations causing partial loss and folding of tissue.Convolutional neural network(CNN)and generative adversarial network(GAN)are pivotal inmedical image registration.However,existing methods often struggle with severe interference and deformation,as seen in histological images of conditions like Cushing’s disease.We argue that the failure of current approaches lies in underutilizing the feature extraction capability of the discriminator inGAN.In this study,we propose a novel multi-modal registration approach GAN-DIRNet based on GAN for deformable histological image registration.To begin with,the discriminators of two GANs are embedded as a new dual parallel feature extraction module into the unsupervised registration networks,characterized by implicitly extracting feature descriptors of specific modalities.Additionally,modal feature description layers and registration layers collaborate in unsupervised optimization,facilitating faster convergence and more precise results.Lastly,experiments and evaluations were conducted on the registration of the Mixed National Institute of Standards and Technology database(MNIST),eight publicly available datasets of histological sections and the Clustering-Registration-Classification-Segmentation(CRCS)dataset on the Cushing’s disease.Experimental results demonstrate that our proposed GAN-DIRNet method surpasses existing approaches like DIRNet in terms of both registration accuracy and time efficiency,while also exhibiting robustness across different image types. 展开更多
关键词 Histological images registration deformable registration generative adversarial network cushing’s disease machine learning computer vision
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Madelung’s Deformity: Reverse Wedge Osteotomy of the Distal Radius Associate Ulnar Wedge Osteotomy: A Case Report
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作者 Kouassi Kouamé Jean Eric Sery Bada Justin Leopoeld Niaoré +5 位作者 Yao Loukou Blaise M’bra Kouame Innocent Krah Koffi Léopold Kouassi Aya Adelaide Nathacha Assere Yao Aboh Ganyn Robert Arnaud Kodo Michel 《Open Journal of Orthopedics》 2018年第2期33-38,共6页
Madelung deformity is rare, accounting for 1.7% of congenital anomalies. The treatment is essentially surgical and several techniques have been described. We report the result of a case treated in an adult patient by ... Madelung deformity is rare, accounting for 1.7% of congenital anomalies. The treatment is essentially surgical and several techniques have been described. We report the result of a case treated in an adult patient by a double osteotomy of the radius and ulna. The patient is satisfied. 展开更多
关键词 madelung deformity CUNEIFORM OsTEOTOMY Radius ULNA
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Langenskiold Procedure for Madelung’s Deformity:Case Series of Late Sequelae
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作者 Emma C.Paes Caroline M.J.Theunissen +1 位作者 Ralph J.B.Sakkers Arnold H.Schuurman 《Open Journal of Orthopedics》 2014年第11期313-320,共8页
Background: Although many authors advise to postpone surgical intervention until skeletal maturity is reached, the Langenski&ouml;ld procedure—entailing physiolysis and the release of Vickers’ ligament—is a kno... Background: Although many authors advise to postpone surgical intervention until skeletal maturity is reached, the Langenski&ouml;ld procedure—entailing physiolysis and the release of Vickers’ ligament—is a known procedure in case of Madelung’s deformity in children. Although advised in textbooks and recent reviews, the results and late sequelae of this procedure have been poorly documented. The aim of this study is to portray the late effects of this procedure for three patients and emphasize a very careful patient selection. Methods: A retrospective study was performed of the medical records of three patients who underwent a Langenski&ouml;ld procedure with release of Vickers’ ligament for Madelung’s deformity of the wrist. They were recalled for function evaluation and their results are presented in the current study. Results: We report the long term results of three patients (five wrists) who underwent a Langenski&ouml;ld procedure with release of Vickers’ ligament in detail. Mean follow-up was twelve years (range: 11 - 14 years). In all of the operated wrists severe pain recurred due to destruction of the distal radio-ulnar joint. Further salvaging surgeries were necessary, some with highly dissatisfying results. Conclusions: Based on our experience we advise not to perform this procedure until further studies have proven its effectiveness and clear indications. Other techniques are available for later correction of Madelung’s deformity, with similar results on pain relief, wrist function and cosmetics. However, we will advocate conservative treatment until skeletal maturity is reached. 展开更多
关键词 madelungs deformity TREATMENT Langenskiold Physiolysis Vickers’Ligament
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Propagation of crust deformation anomalies related to the Menyuan M_(S) 6.9 earthquake
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作者 Anfu Niu Chong Yue +3 位作者 Zhengyi Yuan Jing Zhao Wei Yan Yuan Li 《Earthquake Research Advances》 CSCD 2023年第4期43-48,共6页
Decoding the variation laws of the deformation field before strong earthquakes has long been recognized as an essential issue in earthquake prediction research. In this paper, the temporal and spatial distribution cha... Decoding the variation laws of the deformation field before strong earthquakes has long been recognized as an essential issue in earthquake prediction research. In this paper, the temporal and spatial distribution characteristics of deformation anomalies in the northeastern margin of the Qinghai-Tibetan Plateau before and after the Menyuan M_(S)6.9 earthquake were studied by using the Fisher statistical test method. By analyzing the characteristics of these anomalies, we found that: 1) The deformation anomalies are mainly distributed in the marginal front area of the Qinghai-Tibetan Plateau, where short-term deformation anomalies are prone to occur due to a high gradient of gravity;2) The deformation anomalies along the northeastern margin of the Qinghai-Tibetan Plateau are characterized by spatial propagation, and the migration rate is about 2.4 km/d. The propagation pattern is counterclockwise, consistent with the migration direction of M_(S)≥ 6.0 earthquakes;3) The time and location of the Menyuan earthquake are related to the group migration of earthquakes with M_(S)≥ 6.0. Finally,based on the results of gravity field variation and the theory of crust stress wave, the law of deformation anomaly distribution was discussed. We suggest that both the deformation propagation along the northeastern margin of the Qinghai-Tibetan Plateau and the earthquake migration are possibly associated with the variation of the stress field caused by subsurface mass flow. 展开更多
关键词 Northeastern margin of Qinghai-Tibetan Plateau Menyuan M_(s)6.9 earthquake deformation propagation Earthquake migration Gravity field
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An Improved Coupled Level Set and Continuous Moment-of-Fluid Method for Simulating Multiphase Flows with Phase Change
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作者 Zhouteng Ye Cody Estebe +8 位作者 Yang Liu Mehdi Vahab Zeyu Huang Mark Sussman Alireza Moradikazerouni Kourosh Shoele Yongsheng Lian Mitsuhiro Ohta M.Yousuff Hussaini 《Communications on Applied Mathematics and Computation》 EI 2024年第2期1034-1069,共36页
An improved algorithm for computing multiphase flows is presented in which the multimaterial Moment-of-Fluid(MOF)algorithm for multiphase flows,initially described by Li et al.(2015),is enhanced addressing existing MO... An improved algorithm for computing multiphase flows is presented in which the multimaterial Moment-of-Fluid(MOF)algorithm for multiphase flows,initially described by Li et al.(2015),is enhanced addressing existing MOF difficulties in computing solutions to problems in which surface tension forces are crucial for understanding salient flow mechanisms.The Continuous MOF(CMOF)method is motivated in this article.The CMOF reconstruction method inherently removes the"checkerboard instability"that persists when using the MOF method on surface tension driven multiphase(multimaterial)flows.The CMOF reconstruction algorithm is accelerated by coupling the CMOF method to the level set method and coupling the CMOF method to a decision tree machine learning(ML)algorithm.Multiphase flow examples are shown in the two-dimensional(2D),three-dimensional(3D)axisymmetric"RZ",and 3D coordinate systems.Examples include two material and three material multiphase flows:bubble formation,the impingement of a liquid jet on a gas bubble in a cryogenic fuel tank,freezing,and liquid lens dynamics. 展开更多
关键词 Moment-of-Fluid(MOF) surface tension Two phase flow Phase change deforming boundaries with change(s)in topology Two-dimensional(2D) Three-dimensional(3D)axisymmetric 3D
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级间分离S形分离钢索高速分离敏感因素分析
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作者 董瑞涛 林三春 +2 位作者 荀飞 刘金峰 付继伟 《导弹与航天运载技术(中英文)》 CSCD 北大核心 2024年第2期7-10,共4页
级间分离S形分离钢索结构复杂,高速分离过程涉及大变形、复杂非线性接触等问题,其动态变形及力学特性分析是工程设计的难点之一。基于Abaqus建立S形分离钢索动态分离仿真模型,分析了S形分离钢索高速分离动态变形过程及力学特性,并通过... 级间分离S形分离钢索结构复杂,高速分离过程涉及大变形、复杂非线性接触等问题,其动态变形及力学特性分析是工程设计的难点之一。基于Abaqus建立S形分离钢索动态分离仿真模型,分析了S形分离钢索高速分离动态变形过程及力学特性,并通过地面试验进一步验证建模方法的正确性。研究了S形分离钢索长度、截面直径、拖尾长度、分离速度等多种敏感因素的影响,对工程实际具有一定的指导意义。 展开更多
关键词 级间分离 s形分离钢索 高速分离 变形过程 力学特性
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基于S-SAR边坡雷达的滑坡形变监测分析研究
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作者 周可鹏 陈旺旺 《矿产勘查》 2024年第S01期138-142,共5页
露天矿山边坡安全是矿山安全的保障,边坡表面变形监测数据分析有助于获得准确的滑坡时间预测,因此,滑坡形变监测分析研究是研究的重点。本文对比分析了两个矿山滑坡时的合成孔径边坡雷达变形监测数据,获得了在滑坡时边坡表面变形监测特... 露天矿山边坡安全是矿山安全的保障,边坡表面变形监测数据分析有助于获得准确的滑坡时间预测,因此,滑坡形变监测分析研究是研究的重点。本文对比分析了两个矿山滑坡时的合成孔径边坡雷达变形监测数据,获得了在滑坡时边坡表面变形监测特征曲线,进而建立了变形特征曲线与滑坡之间的关系。通过分析发现了边坡在发生破坏性变形之前会有多次异常的加速变形现象,这一点与斋藤法的三阶段变形相符。边坡在滑坡前并不会呈加速—匀速—再加速的变形规律,而是会重复多次加速—匀速—加速循环的变形现象。 展开更多
关键词 s-sAR 滑坡 边坡雷达 边坡稳定性 形变监测
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OJU Peyronie’s Disease in an Elderly Ghanaian Gentleman—A Case-Report and Literature Review
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作者 Frank Obeng Aishah Fadila Adamu +16 位作者 Samuel Edudzi Gavor Blessings Yao Setsoafia Sedem Atimpo Ebenezer Antwi Enoch Kwaku Adjaho Nana Yaa Agyenim Boateng Merveille Adjin Anum-Laryea Gwendolyn Egyefi Armah Juliet Enyonam Dzivenu Frank Fosu Joel Kwame Kwao Alexander Kofi Quansah Pearl Esi Demawu Hussein Rachel Akosua Sogbe Kafui Kossi Kekessie Mawuenyo Attawa Oyortey Ali Mamudu Ayamba 《Open Journal of Urology》 2024年第10期519-531,共13页
Background: Peyronie’s disease is characterized by fibrous plaque formation in the tunica albuginea, leading to penile curvature and sexual dysfunction. Surgical correction is often required in cases of severe deform... Background: Peyronie’s disease is characterized by fibrous plaque formation in the tunica albuginea, leading to penile curvature and sexual dysfunction. Surgical correction is often required in cases of severe deformity or significant functional impairment. Aim: To present the case of a patient with severe Peyronie’s disease who underwent surgical correction using an autologous fascia lata graft. Case Presentation: We report the case of a 77-year-old Black-African gentleman with Peyronie’s disease, presenting with a self-reported penile curvature of 70 degrees and significant sexual frustration. He was managed surgically with plaque excision followed by a tunica albuginea patch using a subcutaneously harvested autologous fascia lata graft, all performed in a single surgical session. Conclusion: This case highlights the importance of individualized surgical planning and patient-specific considerations in achieving optimal outcomes in the management of Peyronie’s disease, particularly in cases requiring grafting for severe curvature. 展开更多
关键词 Peyronie’s Disease Penile Trauma Tunica Albuginea Penile deformity sexual Frustration Careful Diagnosis Tailored-surgical Therapy Calcific-Plaques Autologous Fascia Lata Graft Water-Tight Repair
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基于NAR神经网络和R/S分析法的隧道围岩变形预测分析
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作者 陈杨 徐浩博 赵明慧 《工程建设》 2024年第5期31-36,共6页
为研究隧道围岩变形非线性特点,采用NAR神经网络和R/S分析法,对隧道围岩变形量和变形趋势进行分析。通过NAR神经网络对变形监测样本进行误差分析,认为NAR神经网络对围岩变形短期预测时的误差小精度高。运用R/S分析法对各变形时间序列进... 为研究隧道围岩变形非线性特点,采用NAR神经网络和R/S分析法,对隧道围岩变形量和变形趋势进行分析。通过NAR神经网络对变形监测样本进行误差分析,认为NAR神经网络对围岩变形短期预测时的误差小精度高。运用R/S分析法对各变形时间序列进行重标极差分析,获得各时序的Hurst指数,分析其与围岩变形趋势的关系,并通过Hurst指数对隧道围岩变形趋势进行判定。结果表明:算例中的断面围岩变形仍然会呈增长趋势,但增长幅度在减小,且水平收敛的趋势性强于拱顶沉降,说明前者受随机扰动影响较小,后期稳定性相对更高。通过运用R/S分析法进行时间序列分析,不仅为围岩变形趋势预判提供了Hurst指数判据,同时也为围岩稳定性分析及治理提供了一种依据。 展开更多
关键词 隧道围岩 变形预测 R/s分析法 NAR神经网络
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Clinical study of correction of finger flexion deformity in Dupuytren's disease
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作者 沈尊理 《外科研究与新技术》 2011年第4期270-270,共1页
Objective To explore surgical technique and its result in correcting finger contracture in Dupuytren’s disease. Methods Seventeen cases of Dupuytren’s disease with 58 years mean age were studied in this group ( 15 m... Objective To explore surgical technique and its result in correcting finger contracture in Dupuytren’s disease. Methods Seventeen cases of Dupuytren’s disease with 58 years mean age were studied in this group ( 15 males and 2 females) . Among them,8 sides were with flexion eontracture of little finger,8 sides with flexion contracture of little and ring fingers,1 side with 展开更多
关键词 Clinical study of correction of finger flexion deformity in Dupuytren’s disease
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Preliminary analysis on characteristics of coseismic deformation associated with M_S=8.1 western Kunlunshan Pass earthquake in 2001 被引量:34
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作者 单新建 柳稼航 马超 《地震学报》 CSCD 北大核心 2004年第5期474-480,共7页
Based on the analysis of coseismic deformation in the macroscopic epicentral region extracted by Differential Interferometric Synthetic Aperture Radar (D-InSAR), and combined with the seismic activity, focal mechanism... Based on the analysis of coseismic deformation in the macroscopic epicentral region extracted by Differential Interferometric Synthetic Aperture Radar (D-InSAR), and combined with the seismic activity, focal mechanism solutions of the earthquake and field investigation, the characteristic of coseismic deformation of MS=8.1 western Kunlunshan Pass earthquake in 2001 was researched. The study shows that its epicenter lies in the northeast side of Hoh Sai Hu; and the seismogenic fault in the macroscopic epicentral region can be divided into two central deformation fields: the west and east segments with the lengths of 42 km and 48 km, respectively. The whole fault extends about 90 km. From the distribution of interferometry fringes, the characteristic of sinistral strike slip of seismogenic fault can be identified clearly. The deformations on both sides of the fault are different with an obviously higher value on the south side. In the vicinity of macroscopic epicenter, the maximum displacement in look direction is about 288.4 cm and the minimum is 224.0 cm; the maximum sinistral horizontal dislocation of seismogenic fault near the macroscopic epicenter is 738.1 cm and the minimum is 551.8 cm. 展开更多
关键词 合成孔径雷达干涉技术 昆仑山口西8.1级地震 同震形变场
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2022年9月5日四川泸定M_(S)6.8地震序列发震构造 被引量:16
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作者 易桂喜 龙锋 +10 位作者 梁明剑 赵敏 张会平 周荣军 李勇 刘欢 吴朋 王思维 李俊 吴微微 苏金蓉 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2023年第4期1363-1384,共22页
2022年9月5日在四川省泸定县磨西镇发生M_(S)6.8强烈地震,极震区烈度达Ⅸ度,共造成97人遇难,20人失联.本文利用截至2022年10月22日的震相数据和波形资料,对本次地震序列进行了重新定位,并利用CAP波形反演方法,计算了主震与M_(S)>3.0... 2022年9月5日在四川省泸定县磨西镇发生M_(S)6.8强烈地震,极震区烈度达Ⅸ度,共造成97人遇难,20人失联.本文利用截至2022年10月22日的震相数据和波形资料,对本次地震序列进行了重新定位,并利用CAP波形反演方法,计算了主震与M_(S)>3.0余震的震源机制解,初步分析了该序列的发震构造及其几何结构特征和震源区构造变形特征.序列重新定位结果表明,泸定M_(S)6.8地震余震区长轴沿鲜水河断裂带南段磨西段呈NNW向展布,余震密集区长约55 km,北端和南端大致止于泸定新店子北侧和石棉草科乡南侧.余震存在明显的分区丛集特征,且在南门关南侧和湾东附近各存在一个余震稀疏区,将余震区自然划分为北、中、南三段,北段和南段相对较窄、中段较宽.M_(S)6.8主震与10月22日泸定M_(S)5.0余震位于中段,9月7日石棉M_(S)4.5余震位于南段,北段无M_(S)4.0以上余震活动.CAP反演结果显示,主震矩震级MW6.44,震源机制解节面参数(走向/倾角/滑动角)为:节面Ⅰ75°/90°/155°,节面Ⅱ165°/65°/0°,矩心深度3.0 km;7次M_(S)>3.0余震的矩心深度在2.5~7.5 km之间,反映本次泸定主震及其3.0级以上余震能量释放主要发生在上地壳浅部.面应变As值揭示主震为纯走滑型,而余震震源机制解分段特征显著,南段和北段均为纯走滑型,中段为拉张(正断)型.基于余震空间分布、序列震源机制解与余震区构造展布,推测本次泸定M_(S)6.8地震的主发震断层为鲜水河断裂带南段NNW走向的磨西段(磨西断裂),左旋走滑,其断层面走向、倾角和倾向均呈现明显的分段差异,揭示主发震构造几何结构具有复杂性,但应变花形态揭示石棉草科乡以北的主发震断层构造变形模式具有很好的一致性,呈NE向拉张、NW向挤压等量的纯走滑变形模式.余震区中段主震西侧3次M_(S)>3.0正断型余震与2016年泸定震群4次M_(S)≥3.4纯正断和斜滑正断型地震应变花揭示该区域发震断层呈NE向拉张分量为主或NE向纯拉张的变形模式,主震西侧可能存在一系列走向SSE(NNW)的正断型微破裂(~2 km),震源机制解给出的两个节面倾向表明高海拔的贡嘎山山体在震间及同震过程中或存在垮塌现象. 展开更多
关键词 泸定M_(s)6.8地震 重新定位 震源机制 发震构造 构造变形模式
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Discovering Crustal Deformation Bands by Processing Regional Gravity Field 被引量:11
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作者 YANG Wencai SUN Yanyun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期66-74,共9页
Objectives: This article presents a new computational procedure to discover scratches buried in the earth's crust. We also validate this new interdisciplinary analysis method with regional gravity data located in a ... Objectives: This article presents a new computational procedure to discover scratches buried in the earth's crust. We also validate this new interdisciplinary analysis method with regional gravity data located in a well-known Dabie orogenic zone for test. Methods: Based on the scratch analysis method evolved with mathematical morphology of surfaces, we present a procedure that extracts information of the crustal scratches from regional gravity data. Because the crustal scratches are positively and highly correlated to crustal deformation bands, it can be used for delineation of the crustal deformation belts. The scratches can be quantitatively characterized by calculation of the ridge coefficient function, whose high value traces delineate the deformation bands hidden in the regional gravity field. In addition, because the degree of crustal deformation is an important indicator of tectonic unit divisions, so the crust can be further divided according to the degree of crustal deformation into some tectonic units by using the ridge coefficient data, providing an objective base map for earth scientists to build tectonic models with quantitative evidence. Results: After the ridge coefficients are calculated, we can further enhance the boundary of high ridge-coefficient blocks, resulting in the so-called ridge-edge coefficient function. The high-value ridge-edge coefficients are well correlated with the edge faults of tectonic units underlay, providing accurate positioning of the base map for compilation of regional tectonic maps. In order to validate this new interdisciplinary analysis method, we select the Dabie orogenic zone as a pilot area for test, where rock outcrops are well exposed on the surface and detailed geological and geophysical surveys have been carried out. Tests show that the deformation bands and the tectonic units, which are conformed by tectonic scientists based on surface observations, are clearly displayed on the ridge and ridge-edge coefficient images obtained in this article. Moreover, these computer-generated images provide more accurate locations and geometric details. Conclusions: This work demonstrates that application of modern mathematical tools can promote the quantitative degree in research of modern geosciences, helping to open a door to develop a new branch of mathematical tectonics. 展开更多
关键词 TECTONICs earth's crust deformation band regional gravity field information extraction scratch analysis computer-generated image
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S形空间曲线顶管开挖引起的地表沉降计算——以宁波市潘桥变电站迁建工程为例 被引量:4
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作者 许有俊 孟毅欣 +3 位作者 张朝 韩志强 郭飞 高胜雷 《隧道建设(中英文)》 CSCD 北大核心 2023年第1期48-57,共10页
为研究S形空间曲线顶管隧道施工引起的地表沉降规律,基于Mindlin弹性力学解和随机介质理论,构建S形空间曲线顶管施工引起的地表沉降计算模型,获得顶管施工各参数和空间曲线段施工地层损失引起的沉降规律,并与宁波市潘桥变电站顶管隧道... 为研究S形空间曲线顶管隧道施工引起的地表沉降规律,基于Mindlin弹性力学解和随机介质理论,构建S形空间曲线顶管施工引起的地表沉降计算模型,获得顶管施工各参数和空间曲线段施工地层损失引起的沉降规律,并与宁波市潘桥变电站顶管隧道工程地表沉降实测值进行对比验证。研究结果表明:1)考虑顶管施工引起的附加荷载、水平与竖向超挖间隙等因素所构建的S形空间曲线顶管施工引起的地表沉降计算方法,理论计算值与实测值吻合较好,能够对地表沉降进行较为准确的预测;2)空间曲线顶管施工引起的地表沉降槽不以顶管中心轴线对称,在顶管机头无超挖刀参与掘进的情况下,最大沉降值向弯道外侧偏移,且顶管机平面转弯产生的超挖间隙对沉降槽偏移影响最大;3)在S形空间曲线顶进时,地层损失是造成地表沉降的主要原因,应严格控制注浆参数,理论注浆量应包括环形空隙与超挖间隙注浆量体积之和。 展开更多
关键词 s形曲线顶管隧道 MINDLIN解 随机介质理论 地表变形
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Multidisciplinary diagnostic dilemma in differentiating Madelung’s disease—the value of superb microvascular imaging technique:A case report 被引量:5
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作者 Goda Seskute Austeja Dapkute +3 位作者 Dominyka Kausaite Sandra Strainiene Andrius Talijunas Irena Butrimiene 《World Journal of Clinical Cases》 SCIE 2021年第21期6145-6154,共10页
BACKGROUND Madelung’s disease,also known as multiple symmetrical lipomatosis,is a rare,underrecognized disorder of fat metabolism that results in unusual accumulation of subcutaneous fat deposits around the neck,shou... BACKGROUND Madelung’s disease,also known as multiple symmetrical lipomatosis,is a rare,underrecognized disorder of fat metabolism that results in unusual accumulation of subcutaneous fat deposits around the neck,shoulders,upper arms,trunk,hips,and upper thighs.Our case demonstrates the importance of differential diagnosis and the value of a superb microvascular imaging technique for suspecting and confirming Madelung’s disease.Timely diagnosis and alcohol abstinence could prevent the progression of growing fatty masses and prevent surgery.CASE SUMMARY A 62-year-old male was admitted to the Rheumatology center complaining of symmetric subcutaneous tumors in the area of the parotid and submandibular salivary glands,small soft masses in the occiput and upper third of the forearm,rashes on calves.A high titer of rheumatoid factor and low concentrations of serum complements were detected.The high-end ultrasound and magnetic resonance imaging examinations of all affected areas of the soft tissues showed predominantly adipose tissue(lipomas)without suspicion of liposarcoma.The biopsy from the small salivary gland revealed no pathology.After evaluating the patient’s clinical presentation(symmetrical lipomatosis,cirrhosis,gynecomastia,anemia,hyperuricemia),Madelung’s disease,type I,along with the psoriatic rash and psoriatic arthritis and secondary liver cirrhosis were established.CONCLUSION Madelung’s disease consists of many co-occurring disorders imitating and overlapping with other conditions.Ultrasonography is the first choice for suspecting and confirming symmetrical lipomatosis. 展开更多
关键词 madelungs disease Multiple symmetrical lipomatosis Cirrhosis salivary gland tumors superb microvascular imaging Case report
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2022年门源M_(S)6.9地震前后垂直形变
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作者 张四新 郝明 +1 位作者 贾鹏 侯伯文 《地震地磁观测与研究》 2023年第S01期240-242,共3页
1研究背景据中国地震台网测定2022年1月8日1时45分,青海省海北州门源县发生M_(S)6.9地震(37.77°N,101.26°E),震源深度为10 km,这是继1986年8月26日门源M_(S)6.4地震(37.70°N,101.50°E)和2016年1月21日门源M_(S)6.4... 1研究背景据中国地震台网测定2022年1月8日1时45分,青海省海北州门源县发生M_(S)6.9地震(37.77°N,101.26°E),震源深度为10 km,这是继1986年8月26日门源M_(S)6.4地震(37.70°N,101.50°E)和2016年1月21日门源M_(S)6.4地震(37.68°N,101.62°E)之后该区域发生的又一次6级以上强震。 展开更多
关键词 2022年门源M_(s)6.9地震 跨断裂水准 垂直形变 童子坝水准 大梁水准
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Benign symmetric lipomatosis (Madelung’s disease) with concomitant incarcerated femoral hernia: A case report 被引量:2
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作者 Bo Li Zheng-Xing Rang +2 位作者 Jia-Cong Weng Guo-Zuo Xiong Xian-Peng Dai 《World Journal of Clinical Cases》 SCIE 2020年第21期5474-5479,共6页
BACKGROUND Benign symmetric lipomatosis(BSL)was first described by Brodie in 1846 and defined as Madelung’s disease by Madelung in 1888.At present,about 400 cases have been reported worldwide.Across these cases,surgi... BACKGROUND Benign symmetric lipomatosis(BSL)was first described by Brodie in 1846 and defined as Madelung’s disease by Madelung in 1888.At present,about 400 cases have been reported worldwide.Across these cases,surgical resection remains the recommended treatment.Here we report a case of neck BSL with concomitant thick fatty deposit in the inguinal region,which concealed the signs of a right incarcerated femoral hernia.CASE SUMMARY A 69-year-old male patient was admitted to our hospital with“abdominal pain,abdominal distension,nausea-vomiting and difficult defecation for half a month”.Moreover,he had a mass in the right inguinal region for more than 10 years.An egg-sized neck mass also developed 15 years ago and had developed into a full neck enlargement 1 year later.In addition,the patient had a history of heavy alcohol consumption for more than 40 years.With the aid of computerized tomography scan,the patient was diagnosed with BSL and a low intestinal mechanical obstruction caused by a right inguinal incarcerated hernia.Under general anesthesia,right inguinal incarcerated femoral hernia loosening and tension-free hernia repair was performed.However,this patient did not receive BSL resection.After a 1-year follow-up,no recurrence of the right inguinal femoral hernia was found.Moreover,no increase in fat accumulation was found in the neck or other areas.CONCLUSION Secretive intraperitoneal fat increase may be difficult to detect,but a conservative treatment strategy can be adopted as long as it does not significantly affect the quality-of-life. 展开更多
关键词 Benign symmetric lipomatosis madelungs disease Neck Inguinal region Inguinal incarcerated hernia Case report
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Numerical simulation of influences of the earth medium's lateral heterogeneity on co- and post-seismic deformation 被引量:3
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作者 Xu Bei Xu Caijun 《Geodesy and Geodynamics》 2015年第1期46-54,共9页
Many studies revealed that the Earth medium's lateral heterogeneity can cause considerable effects on the co- and post-seismic deformation field. In this study, the threedimensional finite element numerical method ar... Many studies revealed that the Earth medium's lateral heterogeneity can cause considerable effects on the co- and post-seismic deformation field. In this study, the threedimensional finite element numerical method are adopted to quantify the effects of lateral heterogeneity caused by material parameters and fault dip angle on the co- and postseismic deformation in the near- and far-field. Our results show that: 1) the medium's lateral heterogeneity does affect the co-seismic deformation, with the effects increasing with the medium's lateral heterogeneity caused by material parameters; 2) the Lame parameters play a more dominant role than density in the effects caused by lateral heterogeneity; 3) when a fault's dip angle is smaller than 90, the effects of the medium's lateral heterogeneity on the hanging wall are greater than on the footwall; 4) the impact of lateral heterogeneity caused by the viscosity coefficient on the post-seismic deformation can affect a large area, including the near- and far-field. 展开更多
关键词 Finite element method Medium s lateral heterogeneity Numerical simulation Co-seismic deformation Post-seismic deformation Geod
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