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The Subduction Structure Beneath the New Britain Island Arc and the Adjacent Region from Double-Difference Tomography
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作者 ZHANG Hao GONG Wei +2 位作者 XING Junhui XU Chong LI Chaoyang 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第1期107-118,共12页
We applied double-difference tomography to relocate seismic events and determine the lithospheric velocity structure beneath the New Britain Island arc and the South Bismarck Sea Basin,based on the local P wave arriva... We applied double-difference tomography to relocate seismic events and determine the lithospheric velocity structure beneath the New Britain Island arc and the South Bismarck Sea Basin,based on the local P wave arrival time dataset collected by the International Seismological Centre.Results of the seismic relocation and velocity inversion show that the subduction of Solomon Sea Plate along the New Britain Trench is spatially different above 150 km,and the subduction angle of the slab on the west side is higher than that on the east side.The relocated earthquakes also show that there are double seismic zones at the depths of about 30–90km beneath the New Britain Island Arc.The velocity structure shows that the dehydration of the subducting slab caused the low-velocity anomalies in mantle wedge above the slab,which are associated with the magmatic activities around the New Guinea-New Britain Island arc.Moreover,it shows that there is another low-velocity anomaly zone beneath the Bismarck mid-oceanic ridge with spatial variation.Beneath the west of the Bismarck mid-oceanic ridge,the low-velocity anomaly is weakly connected to the subducted Solomon Sea slab.Conversely,the low-velocity anomaly beneath the Manus Sea Basin is highly intertwined to the subducting slab and its mantle wedge,indicating that the subduction of the Solomon Sea Plate might be a key deep dynamic factor that drives the spreading of the Manus Sea Basin and the separation of the Bismarck Plate. 展开更多
关键词 New Britain Trench Bismarck Sea Basin Manus Sea Basin double-difference tomography
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Double-difference tomography of P- and S-wave velocity structure beneath the western part of Java, Indonesia
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作者 Shindy Rosalia Sri Widiyantoro +1 位作者 Andri Dian Nugraha Pepen Supendi 《Earthquake Science》 2019年第1期12-25,共14页
West Java in the western part of the Sunda Arc has a relatively high seismicity due to subduction activity and faults.In this study,double-difference tomography was used to obtain the 3D velocity tomograms of P and S ... West Java in the western part of the Sunda Arc has a relatively high seismicity due to subduction activity and faults.In this study,double-difference tomography was used to obtain the 3D velocity tomograms of P and S waves beneath the western part of Java.To infer the geometry of the structure beneath the study area,precise earthquake hypo・center determination was first performed before tomographic imaging.For this,earthquake waveform data were extracted from the regional Meteorological,Climatological,Geophysical Agency(BMKG)network of Indonesia from South Sumatra to Central Java.The P and S arrival times for about 1,000 events in the period April 2009 to July 2016 were selected,the key features being events of magnitude>3,azimuthal gap<210°and number of phases>8.A nonlinear method using the oct-tree sampling algorithm from the NonLinLoc program was employed to determine the earthquake hypocenters.The hypocenter locations were then relocated using double-difference tomography(tomoDD).A significant reduction of travel-time(root mean square basis)and a better clustering of earthquakes were achieved which correlated well with the geological structure in West Java.Double-difference tomography was found to give a clear velocity structure,especially beneath the volcanic arc area,i.e.,under Mt Anak Krakatau,Mt Salak and the mountains complex in the southern part of West Java.Low velocity anomalies for the P and S waves as well as the vp/vs ratio below the volcanoes indicated possible partial melting of the upper mantle which ascended from the subducted slab beneath the volcanic arc. 展开更多
关键词 West Java P-and S-wave velocity structures double-difference tomography
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Seismic imaging of the middle and upper crust by double-difference tomography:the Haicheng earthquake (Ms 7.3) in Liaoning Province 被引量:10
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作者 Zheng Que Liu Cai +1 位作者 Tian You and Zhu Hong-Xiang 《Applied Geophysics》 SCIE CSCD 2018年第1期125-136,150,共13页
The Haicheng earthquake (Ms 7.3) occurred in Liaoning Province (39°N-43°N, 120°E-126°E ), China on February 4, 1975. The mortality rate was only 0.02% owing to the first timely and accurate pre... The Haicheng earthquake (Ms 7.3) occurred in Liaoning Province (39°N-43°N, 120°E-126°E ), China on February 4, 1975. The mortality rate was only 0.02% owing to the first timely and accurate prediction, although the area affected by the earthquake was 9200 km^2 and covered cities with a population density of 1000 p/km^2. In this study, the double- difference (DD) tomography method was used to obtain high-resolution three-dimensional (3D) P- and S-wave velocity (Vp and Vs) structures and Vp/Vs as well as the earthquake locations. Tomography results suggest that velocity structure at shallow depth coincides well with topography and sediment thickness. The earthquake locations form a northwest-striking zone associated with the Jinzhou(JZ) Fault and a northeast-striking zone associated with the Haichenghe-Dayanghe (HD) Fault, and suggest that the JZ Fault consists of three faults and the Ms 7.3 Haicheng earthquake originated at the intersection of the JZ and the Faults. Low- velocity zones (LVZs) with low Vp/Vs are observed at 15-20 km depth beneath the Haicheng (HC) region. We interpret the LVZs in the middle crust as regions of fluids, suggesting rock dehydration at high temperatures. The LVZs and low Vp/Vs in the upper crust are attributed to groundwater-filled cracks and pores. We believe that large crustal earthquakes in this area are caused by the combination of faulting and fluid movement in the middle crust. 展开更多
关键词 Haicheng earthquake DD tomography VP Vs low velocity zone
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Therapeutic approaches to diabetic macular edema assessed using optical coherence tomography and optical coherence tomography angiography
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作者 Parisa Alsadat Dadkhah Hamed Taheri +14 位作者 Masoud Noroozi Asma Rasouli Zahra Sheikh Saba Imanparvar Saeed Zivari Lashkajani Nahid Samadi Javad Nadem Behzadmehr Amirian Goharsharieh Alishiri Ata Akhtari Kohnehshahri Arshia Shafiei Amirreza Heydarlou Reza Khademi Anahita Rahmati Niloofar Deravi 《International Journal of Ophthalmology(English edition)》 2026年第1期160-174,共15页
Overt and harmful diabetes mellitus(DM)has detrimental effects on individuals and,by extension,the community.Among the microvascular DM complications is diabetic retinopathy(DR).DR may cause irreversible vision deteri... Overt and harmful diabetes mellitus(DM)has detrimental effects on individuals and,by extension,the community.Among the microvascular DM complications is diabetic retinopathy(DR).DR may cause irreversible vision deterioration in cases of poor blood glucose regulation.Changes in vascular permeability are key trigger points for diabetic macular edema(DME),a condition characterized by the accumulation of fluid in the macula.The development of vascular endothelial growth factor(VEGF)pathway inhibitors has provided a pathogenesis-based treatment approach for DME.Optical coherence tomography(OCT)provides highresolution imaging of the anatomy,including the aging of DME and its structural damage,in distinct morphologic subtypes of macular edema,thereby supporting the assessment of macular edema treatment.The availability of repeated OCT monitoring provides clinical reassurance through the treatment.OCT angiography(OCTA)provides retinal blood flow maps with high spatial resolution.The ability promotes an understanding of disease pathogenesis and facilitates the implementation of new therapeutic methods.This review compares the potential of OCT and OCTA in the diagnosis and treatment of DME,as well as their respective therapeutic applications. 展开更多
关键词 diabetic macular edema optical coherence tomography optical coherence tomography angiography vascular endothelial growth factor
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Photoacoustic-computed tomography 3D data compression method and system based on Wavelet-Transformer
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作者 Jialin Li Tingting Li +2 位作者 Yiming Ma Yi Shen Mingjian Sun 《Journal of Innovative Optical Health Sciences》 2026年第1期110-125,共16页
Photoacoustic-computed tomography is a novel imaging technique that combines high absorption contrast and deep tissue penetration capability,enabling comprehensive three-dimensional imaging of biological targets.Howev... Photoacoustic-computed tomography is a novel imaging technique that combines high absorption contrast and deep tissue penetration capability,enabling comprehensive three-dimensional imaging of biological targets.However,the increasing demand for higher resolution and real-time imaging results in significant data volume,limiting data storage,transmission and processing efficiency of system.Therefore,there is an urgent need for an effective method to compress the raw data without compromising image quality.This paper presents a photoacoustic-computed tomography 3D data compression method and system based on Wavelet-Transformer.This method is based on the cooperative compression framework that integrates wavelet hard coding with deep learning-based soft decoding.It combines the multiscale analysis capability of wavelet transforms with the global feature modeling advantage of Transformers,achieving high-quality data compression and reconstruction.Experimental results using k-wave simulation suggest that the proposed compression system has advantages under extreme compression conditions,achieving a raw data compression ratio of up to 1:40.Furthermore,three-dimensional data compression experiment using in vivo mouse demonstrated that the maximum peak signal-to-noise ratio(PSNR)and structural similarity index(SSIM)values of reconstructed images reached 38.60 and 0.9583,effectively overcoming detail loss and artifacts introduced by raw data compression.All the results suggest that the proposed system can significantly reduce storage requirements and hardware cost,enhancing computational efficiency and image quality.These advantages support the development of photoacoustic-computed tomography toward higher efficiency,real-time performance and intelligent functionality. 展开更多
关键词 Photoacoustic-computed tomography data compression TRANSFORMER
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Three-dimensional characterization of intermetallic compound formation in magnesium alloys with micro X-ray computed tomography
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作者 SUN Wei HU Xiao-juan +5 位作者 DENG Yang-chao YANG Yang YAO Hu ZHANG Yong-hong ZHANG Rui-feng ZENG Guang 《Journal of Central South University》 2026年第1期160-174,共15页
This comprehensive study investigates the formation and evolution of intermetallic compounds during the solidification process of magnesium alloys using advanced micro X-ray computed tomography.By analyzing both commo... This comprehensive study investigates the formation and evolution of intermetallic compounds during the solidification process of magnesium alloys using advanced micro X-ray computed tomography.By analyzing both common industrial Mg-Al-Zn alloys and a novel rare earth-containing Mg-Ni-Gd-Y alloy,we aim to characterize the nucleation,growth,and distribution of Al-Mn and eutectic intermetallics across various stages of solidification.The non destructive imaging technique employed in this research provides high-resolution,three-dimensional insights into the microstructural development,allowing for a detailed examination of the morphology,spatial arrangement,and interconnectivity of intermetallic phases.This approach overcomes limitations of traditional two-dimensional metallographic methods,offering a more comprehensive understanding of the complex three-dimensional structures formed during solidification. 展开更多
关键词 magnesium alloy X-ray computed tomography SOLIDIFICATION INTERMETALLICS DEFECTS
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Reinforcement learning for muon scattering tomography enhancement
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作者 Yi-Ni Wu Yuan-Yuan Liu +7 位作者 Li Wang Jian-Jie Zhang Ning Su Wen-Wan Ding Xin Zhao Zhi Zhou Peng Zheng Jian-Ping Cheng 《Nuclear Science and Techniques》 2026年第5期182-198,共17页
Muon scattering tomography(MST) is a powerful noninvasive imaging technique with significant applications in nuclear material detection and security screening.Traditional MST usually relies on the point of closest app... Muon scattering tomography(MST) is a powerful noninvasive imaging technique with significant applications in nuclear material detection and security screening.Traditional MST usually relies on the point of closest approach(PoCA) algorithm to reconstruct images from muon scattering data;however,PoCA often suffers from suboptimal image clarity and resolution.To overcome these challenges,we propose a novel approach that leverages reinforcement learning(RL) to enhance MST reconstruction,termed the μRL-enhanced method.By framing the MST optimization task as an RL problem,we developed an intelligent agent capable of dynamically adjusting the key PoCA parameters.The agent is trained using a multi-objective reward function that guides the optimization toward higher-quality reconstructions.Our experimental results show that theμRL-enhanced method significantly outperforms the traditional PoCA baseline acros s multiple benchmark metrics.Specifically,the proposed approach on average attains a 307% improvement in the intersection over union(IoU),a 79% increase in the structural similarity index measure(SSIM),and a 8.4% enhancement in the peak signal-to-noise ratio(PSNR) across four experiments.Furthermore,when benchmarked against the maximum likelihood scattering and displacement(MLSD)algorithm,the μRL-enhanced method offers modest gains in PS NR and IoU,together with a one-third increase in SSIM.These improvements demonstrate the enhanced reconstruction accuracy and structural fidelity of the μRL-enhanced method,highlighting its potential to advance MST technologies and their applications. 展开更多
关键词 Muon scattering tomography Reinforcement learning Q-LEARNING PoCA
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Optical coherence tomography for surgical demarcation of GI tumor margins for accelerated decision-making during the surgical resection of tumors
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作者 Mohamed Nijas Veluthedath Anuradha Sekaran +3 位作者 Manjoosha R Yerrapragada Pradeep Rebala Duvvuru Nageshwar Reddy Renu John 《Journal of Innovative Optical Health Sciences》 2026年第2期116-128,共13页
Gastric cancer,including stomach tumors,poses significant health challenges due to late-stage diagnosis and limited early detection methods.Accurate imaging and precise tumor margin demarcation are critical for effect... Gastric cancer,including stomach tumors,poses significant health challenges due to late-stage diagnosis and limited early detection methods.Accurate imaging and precise tumor margin demarcation are critical for effective treatment planning and improved patient outcomes.Conventional imaging techniques,such as endoscopy and histopathology,provide valuable diagnostic information but cannot offer real-time assessment.We aim to explore the application of optical coherence tomography(OCT),combined with statistical and machine learning methods,for rapid tumor margin demarcation in gastrointestinal(GI)cancer tissues in exvivo.GI tumor specimens from 17 patients were imaged intraoperatively with OCT.Quantitative features were extracted from the images,and statistical and machine learning analyses were applied to distinguish tissue types.Subsequent histopathological evaluation was used as the reference standard for validation.The combination of OCT imaging and data-driven analysis enables clear differentiation between healthy,marginal and tumor tissues in near real-time.The KNN model achieved the highest classification accuracy(0.921±0.040),with SVM(0.906±0.038)and Extra Trees(0.901±0.034)also demonstrating robust performance in discriminating tissue margins.OCT findings demonstrate strong agreement with histopathology.Integrated with statistical and machine learning techniques,OCT enables rapid assessment of GI tumor margins.This approach provides quantitative objectivity and real-time feedback,closely approximating histopathological analysis and supporting improved surgical decision-making. 展开更多
关键词 Optical coherence tomography gastrointestinal tumor tumor demarcation optical biopsy
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High-contrast optical coherence tomography angiography via log-scale inverse static-to-dynamic ratio analysis for weak flow signal
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作者 Jinyu Fan Jiangjie Huang +4 位作者 Ning Tang Jingye Gu Lina Xing Yi He Guohua Shi 《Advanced Photonics Nexus》 2026年第1期71-81,共11页
The conventional optical coherence tomography angiography(OCTA)algorithm is implemented in the linear domain,which may lead to the neglect of weak blood flow information.Logarithmic transformation is widely used in si... The conventional optical coherence tomography angiography(OCTA)algorithm is implemented in the linear domain,which may lead to the neglect of weak blood flow information.Logarithmic transformation is widely used in signal analysis to improve the contrast of weak signals.However,decorrelation-based OCTA in the logarithmic domain is also sensitive to the signal-to-noise ratio(SNR)even in high SNR regions,introducing strong flow artifacts that severely reduce the blood vessel contrast.A metric—static-to-dynamic ratio(SDR)—was used to quantify weak flow signals,and a weak flow model among decorrelation,SDR,and SNR was established.Based on this model,we proposed a log-scale inverse SDR-based OCTA method(logiSDR-OCTA),which simultaneously and effectively reduces SNR-induced flow artifacts in static regions and prevents the attenuation of the flow signal in dynamic regions.The in vivo imaging experiments demonstrated that the contrast of the mouse brain logiSDR images was 2.43 times that of linear-scale decorrelation images and 2.71 times that of log-scale subtraction images;the contrast of the human retina logiSDR images was 4.91 times that of linear-scale decorrelation images and 3.56 times that of log-scale subtraction images. 展开更多
关键词 optical coherence tomography angiography static-to-dynamic ratio retina imaging
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Ultrasound-induced light guiding overcomes contrast and resolution limits in optoacoustic tomography
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作者 Blanca Mestre-Torà XoséLuís Deán-Ben +1 位作者 Daniel Razansky MartíDuocastella 《Advanced Photonics Nexus》 2026年第1期178-185,共8页
Intense light diffusion and attenuation through turbid biological tissues compromise the achievable depth,resolution,and contrast in optoacoustic tomography(OAT).We propose to mitigate this limitation by exploiting ul... Intense light diffusion and attenuation through turbid biological tissues compromise the achievable depth,resolution,and contrast in optoacoustic tomography(OAT).We propose to mitigate this limitation by exploiting ultrasound waves to locally modulate the refractive index of scattering samples,effectively generating embedded light waveguides.Here,the ultrasound-induced waveguides enhanced light delivery into deep targets,achieving up to 110%improvement in contrast-to-noise ratio of OAT images at a depth of eight mean free scattering paths.Furthermore,ultrasound-mediated light focusing enables breaking through the acoustic diffraction limit by attaining 25μm spatial resolution via localization OAT without the need for external circulating contrast agents.These findings demonstrate the potential of ultrasoundinduced light guiding for enabling label-free super-resolution OAT with enhanced contrast and depth. 展开更多
关键词 light scattering ACOUSTO-OPTICS deep imaging optoacoustic tomography non-invasive biomedical imaging
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Characterizing dynamic segregation behavior in cemented paste during pipeline transport through electrical resistance tomography
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作者 Yingjie Chang Aixiang Wu +4 位作者 Zhu’en Ruan Shaoyong Wang Jiandong Wang Shulong Liu Shuangcheng Du 《International Journal of Minerals,Metallurgy and Materials》 2026年第3期798-808,共11页
Cement paste backfill(CPB)technology is a key method for mine waste treatment,and pipeline transport is critical for safe and efficient waste transfer.Variations in raw material properties can cause slurry segregation... Cement paste backfill(CPB)technology is a key method for mine waste treatment,and pipeline transport is critical for safe and efficient waste transfer.Variations in raw material properties can cause slurry segregation,increase pipeline wear and resistance,raise the risk of blockages or bursts,and disrupt operations.To study CPB slurry segregation during transport,CPB was prepared using cement as the cementitious material and unclassified tailings as inert materials.A small annular-tube device using an electrical resistance tomography system was developed to analyze its flow characteristics,and quantitative segregation assessment methods were developed.The results indicated that CPB conductivity increases with transport time but decreases with higher solid mass content,with the latter having a greater impact.At a low solid content,solid particles migrated toward the bottom of the pipe as the flow time increased,and the migratory behavior of the particles diminished as the solid content increased.At a flow rate of 1.25 m/s,the heterogeneity index for CPB with 58wt% solid content increased by 1.24 in 20 min,whereas that for CPB with 62wt% solid content increased by 2.17.Higher solid mass content amplifies the effect of conveying time on segregation,emphasizing the need to balance these factors for minimizing segregation.These insights can guide the optimization of mine pipeline transport systems. 展开更多
关键词 cement paste backfill electrical resistance tomography dynamic segregation pipeline transport
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C-SegNet:a practical approach for automated diabetic macular edema segmentation in optical coherence tomography images
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作者 Zhi-Yuan Guan Ge Deng +6 位作者 Shi-Long Shi Zhen Tang Xian-Kun Dong Qiu-Yi Li Shu-Jing Shen Yong-Ling He Xue-Jun Qiu 《Biomedical Engineering Communications》 2026年第2期15-22,共8页
Background:Diabetic macular edema is a prevalent retinal condition and a leading cause of visual impairment among diabetic patients’Early detection of affected areas is beneficial for effective diagnosis and treatmen... Background:Diabetic macular edema is a prevalent retinal condition and a leading cause of visual impairment among diabetic patients’Early detection of affected areas is beneficial for effective diagnosis and treatment.Traditionally,diagnosis relies on optical coherence tomography imaging technology interpreted by ophthalmologists.However,this manual image interpretation is often slow and subjective.Therefore,developing automated segmentation for macular edema images is essential to enhance to improve the diagnosis efficiency and accuracy.Methods:In order to improve clinical diagnostic efficiency and accuracy,we proposed a SegNet network structure integrated with a convolutional block attention module(CBAM).This network introduces a multi-scale input module,the CBAM attention mechanism,and jump connection.The multi-scale input module enhances the network’s perceptual capabilities,while the lightweight CBAM effectively fuses relevant features across channels and spatial dimensions,allowing for better learning of varying information levels.Results:Experimental results demonstrate that the proposed network achieves an IoU of 80.127%and an accuracy of 99.162%.Compared to the traditional segmentation network,this model has fewer parameters,faster training and testing speed,and superior performance on semantic segmentation tasks,indicating its highly practical applicability.Conclusion:The C-SegNet proposed in this study enables accurate segmentation of Diabetic macular edema lesion images,which facilitates quicker diagnosis for healthcare professionals. 展开更多
关键词 multi-scale input diabetic macular edema image segmentation optical coherence tomography
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Correlation between Optical Coherence Tomography Images and Histological Features in Female Reproductive Tract Lesions
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作者 Xianlin Yuan Yunmiao Chen Rutong Lin 《Journal of Clinical and Nursing Research》 2026年第2期169-175,共7页
Female reproductive tract lesions are diverse,ranging from benign inflammation to malignant tumors,all of which seriously threaten women’s health.Early accurate diagnosis is crucial for improving prognosis.As the“go... Female reproductive tract lesions are diverse,ranging from benign inflammation to malignant tumors,all of which seriously threaten women’s health.Early accurate diagnosis is crucial for improving prognosis.As the“gold standard”for diagnosis,histopathological examination is difficult to meet the needs of clinical screening and dynamic monitoring due to limitations such as invasiveness and sampling restrictions.Optical Coherence Tomography(OCT),as a non-invasive,real-time,and high-resolution imaging technology,can clearly display the microstructure of biological tissues,known as“optical biopsy”,and shows promising application prospects in the diagnosis of female reproductive tract lesions.This article systematically reviews the basic principles of OCT technology,the research progress on the correlation between OCT image features and histological features in lesions of different parts of the female reproductive tract such as the cervix and endometrium,analyzes the diagnostic efficacy,advantages and limitations of OCT technology,and prospects its future development direction,aiming to provide a reference for the clinical application of OCT technology in the diagnosis of female reproductive tract diseases. 展开更多
关键词 Optical Coherence tomography(OCT) HISTOPATHOLOGY Cervical cancer Endometrial cancer
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High-resolution 3D shallow crustal structure of Urumqi foreland thrust tectonic belt,northern Tianshan,based on ambient noise tomography
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作者 Xiang Huang Zhengyang Qiang +1 位作者 Weitao Wang Yuan Yao 《Earthquake Science》 2026年第1期86-96,共11页
The Urumqi foreland thrust tectonic belt exhibits complex geological structures and strong seismicity.Imaging its shallow crustal structure is of great significance for understanding its tectonic mechanism and seismog... The Urumqi foreland thrust tectonic belt exhibits complex geological structures and strong seismicity.Imaging its shallow crustal structure is of great significance for understanding its tectonic mechanism and seismogenic environment.We obtained a high-resolution S-wave velocity model of the shallow crust at depths of 0–8 km using ambient noise tomography applied to data from a dense seismic array.Sediments are generally thinner in the southeast and thicker in the northwest,with a maximum thickness of more than 8 km.Variations in the velocity structure near the Xishan,Wanyaogou,and Yamalike faults indicate that their formation was related to differences in the physical properties on either side of the fault.In addition,the faults exhibit thrusting of the low-velocity sides towards the high-velocity sides.In the study area,earthquakes rarely occur at depths of less than 3 km and are mostly concentrated in the high-velocity zone in the southern part.Below 3 km depth,more earthquakes were observed,mainly distributed near faults or in relatively high-velocity areas in the southern part.This suggests that high-velocity structures are more prone to stress accumulation,resulting in earthquakes.At 6–8 km depth,the densely distributed earthquakes in the northwestern part of the Bogda mountains are well-aligned with the northwest-oriented low-velocity zone observed in this study,suggesting that this weak zone likely controls seismicity in this area. 展开更多
关键词 ambient noise tomography shallow crustal structure thrust fault SEISMICITY Urumqi depression
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Combined multidetector computed tomography and gastrointestinal endoscopy for gastric cancer screening,preoperative staging,and lymph node metastasis detection
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作者 Le-Ping Ye Yan-Ping Zhang +4 位作者 Gang Chen Yi-Xian Wu Cheng-Long He Dong Wang Qiao Mei 《World Journal of Gastrointestinal Oncology》 2026年第1期200-210,共11页
BACKGROUND Early screening,preoperative staging,and diagnosis of lymph node metastasis are crucial for improving the prognosis of gastric cancer(GC).AIM To evaluate the diagnostic value of combined multidetector compu... BACKGROUND Early screening,preoperative staging,and diagnosis of lymph node metastasis are crucial for improving the prognosis of gastric cancer(GC).AIM To evaluate the diagnostic value of combined multidetector computed tomography(MDCT)and gastrointestinal endoscopy for GC screening,preoperative staging,and lymph node metastasis detection,thereby providing a reference for clinical diagnosis and treatment.METHODS In this retrospective study clinical and imaging data of 134 patients with suspected GC who were admitted between January 2023 and October 2024 were initially reviewed.According to the inclusion and exclusion criteria,102 patients were finally enrolled in the analysis.All enrolled patients had undergone both MDCT and gastrointestinal endoscopy examinations prior to surgical intervention.Preoperative clinical staging and lymph node metastasis findings were compared with pathological results.RESULTS The combined use of MDCT and gastrointestinal endoscopy demonstrated a sensitivity of 98.53%,specificity of 97.06%,accuracy of 98.04%,positive predictive value of 98.53%,and negative predictive value of 97.06%for diagnosing GC.These factors were all significantly higher than those of MDCT or endoscopy alone(P<0.05).The accuracy rates of the combined approach for detecting clinical T and N stages were 97.06%and 92.65%,respectively,outperforming MDCT alone(86.76% and 79.41%)and endoscopy alone(85.29% and 70.59%)(P<0.05).Among 68 patients with confirmed GC,50(73.53%)were pathologically diagnosed with lymph node metastasis.The accuracy for detecting lymph node metastasis was 66.00%with endoscopy,76.00%with MDCT,and 92.00% with the combined approach,all with statistically significant differences(P<0.05).CONCLUSION The combined application of MDCT and gastrointestinal endoscopy enhanced diagnostic accuracy for GC,provided greater consistency in preoperative staging,and improved the detection of lymph node metastasis,thereby demonstrating significant clinical utility. 展开更多
关键词 Multidetector computed tomography Gastrointestinal endoscopy Gastric cancer Preoperative staging Lymph node metastasis
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Chronic alcohol consumption on retinal microcirculation in healthy subjects:an optic coherence tomography angiography study
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作者 Dilan Yildiz Tahsin Uzundede +2 位作者 Akin Cakir Gamze Karatas Busra Coban 《International Journal of Ophthalmology(English edition)》 2026年第2期326-332,共7页
AIM:To investigate the effects of chronic alcohol consumption on retinal microcirculation by comparing different alcohol-consuming groups using optical coherence tomography(OCT)and OCT angiography(OCTA).METHODS:This o... AIM:To investigate the effects of chronic alcohol consumption on retinal microcirculation by comparing different alcohol-consuming groups using optical coherence tomography(OCT)and OCT angiography(OCTA).METHODS:This observational clinical study utilized a cross-sectional and prospective design,focusing on chronic alcohol consumers alongside a non-consuming control group.OCT/OCTA imaging parameters including central retinal subfield thickness(CST),subfoveal choroidal thickness(SCT),foveal avascular zone(FAZ)and vessel density(VD)in the superficial and deep capillary plexuses in both the macular and optic disc(OD)regions were recorded.Data were analyzed using SPSS 15.0;descriptive statistics were reported,group comparisons were performed with Chisquare,Kruskal–Wallis,and Bonferroni-corrected Mann–Whitney U tests,and relationships were assessed using Spearman correlation,with statistical significance set at P<0.05.RESULTS:A total of 160 eyes of 160 participants(110 females and 50 males with mean age 38.7±9.9y)who don’t smoke were divided into five groups:never,occasional,monthly,weekly and daily drinkers.The mean CST was 216.6±14.2μm and the mean SCT was 358.9±84.5μm.There was no statistically significantly difference in CST and SCT among the groups(P=0.890,0.799).Foveal superficial capillary plexuses(SCPs)VD was higher in monthly drinkers compared to occasional drinkers(P=0.015).Foveal VD in deep capillary plexus was also higher in monthly drinkers than in never and occasional drinkers(P=0.004,0.006).Nasal SCPs VD at the OD was higher in monthly drinkers compared to never drinkers(P=0.005).There was no significant difference FAZ area among the groups(P=0.071).CONCLUSION:Both superficial and deep microvascular structures in the inferior quadrants of macula are positively correlated with frequency of alcohol use.Also in our study results is that the monthly drinker group has uniquely higher VDs in both macula and OD.This leads us to consider moderate alcohol consumption may also have protective effects on retinal microcirculation. 展开更多
关键词 alcohol consumption foveal avascular zone retinal microcirculation optical coherence tomography angiography vessel density
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Application of electrical impedance tomographyguided PEEP titration in acute respiratory distress syndrome patients with intra-abdominal hypertension
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作者 Hui Wen Maiying Fan +5 位作者 Junliang Xiao Zhiqun Liu Xiaohua Liu Shuzhen Mao Xiaotong Han Fengling Ning 《World Journal of Emergency Medicine》 2026年第1期70-75,共6页
BACKGROUND:Individualized positive end-expiratory pressure(PEEP)titration is a crucial technique in mechanical ventilation therapy for acute respiratory distress syndrome(ARDS)patients with intra-abdominal hypertensio... BACKGROUND:Individualized positive end-expiratory pressure(PEEP)titration is a crucial technique in mechanical ventilation therapy for acute respiratory distress syndrome(ARDS)patients with intra-abdominal hypertension(IAH).This study aimed to evaluate the eff ectiveness of electrical impedance tomography(EIT)-guided PEEP titration in this population.METHODS:This prospective study enrolled 36 ARDS patients,including 22 patients with IAH and 14 without IAH.All the patients underwent EIT-guided PEEP titration at the intersection point between alveolar overdistension and collapse during a decremental PEEP trial.The changes in pulmonary ventilation distribution,respiratory mechanics and hemodynamics during the titration process were observed.RESULTS:After EIT-guided PEEP titration was performed,the PEEP,peak inspiratory pressure and plateau pressure increased significantly(P<0.05).Furthermore,no significant differences were observed in respiratory system compliance,tidal volume,driving pressure,or the 4*DP+RR index between the two groups(P>0.05).The mechanical power increased in the non-IAH(NIAH)group after PEEP titration(P<0.05).Ventilation in gravity-dependent lung regions significantly increased(P<0.05),and the oxygenation index(PaO2/FiO2)improved signifi cantly(P<0.05)in both groups.However,blood pressure,heart rate,respiratory rate,central venous pressure,and lactate levels did not signifi cantly change.In the IAH group,the PaO2/FiO2 ratio improved less than that in the NIAH group did(P<0.05).CONCLUSION:In our study,individualized PEEP titration guided by EIT improved oxygenation in ARDS patients with concomitant IAH without signifi cantly aff ecting hemodynamics.The presence of IAH may limit the improvement of oxygenation during EIT-guided PEEP titration. 展开更多
关键词 Acute respiratory distress syndrome Positive end-expiratory pressure Electrical impedance tomography Intra-abdominal pressure
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Virtual histology imaging of lymph nodes via dynamic full-field optical coherence tomography and deep learning to differentiate metastasis
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作者 Shuwei Zhang Houpu Yang +8 位作者 Yiyin Zhang Xiaoxian Li Jin Zhao Yuanyuan Zhang Ping Xue Hua Kang Hongchuan Jiang Wenhui Ren Shu Wang 《Cancer Biology & Medicine》 2026年第3期418-429,共12页
Objective:The current pathological diagnosis of lymph node metastasis is time-consuming,labor-intensive,and dependent on sectioning of paraffin blocks.Herein,in a prospective cohort of patients with breast cancer,we v... Objective:The current pathological diagnosis of lymph node metastasis is time-consuming,labor-intensive,and dependent on sectioning of paraffin blocks.Herein,in a prospective cohort of patients with breast cancer,we validated dynamic full-field optical coherence tomography(D-FFOCT),a virtual pathology tool integrating deep learning for nodal metastasis detection,and offering rapid and label-free histologic approximations of fresh tissues.Methods:In a prospective dual-center cohort of 155 patients with breast cancer,747 freshly bisected lymph node slides were obtained via D-FFOCT.Surgeons interpreted each slide with histopathology as the gold standard.A deep learning model was trained on 28,911 patches(corresponding to 590 slides)and tested on 7,736 patches(corresponding to 157 slides).The results were mapped to the slide level for potential intraoperative evaluation.Results:D-FFOCT strongly correlated with hematoxylin and eosin(H&E)-stained histological images.Surgeons achieved 97.10%specificity in nodal diagnosis with D-FFOCT.The performance of the artificial intelligence(AI)model was not inferior to that of human experts and had a sensitivity/specificity of 87.88%/91.94%and an area under the receiver operating characteristic curve of 0.899 at the slide level.The human–AI collaborative system reduced labor requirements by 75%and increased the specificity by 6.5%,to 98.39%.Conclusions:D-FFOCT has excellent potential as a tool for assessing lymph node metastatic status without tissue preparation or consumption.The integration of D-FFOCT with deep learning decreases labor demands and maintains high accuracy,thereby enabling streamlined nodal prediction independent of routine pathology procedures. 展开更多
关键词 Breast cancer dynamic full field optical coherence tomography lymph nodes AI model metastatic status
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Short-period dense linear array ambient noise tomography of shallow crustal structure across the Haichenghe fault zone,China
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作者 Mingruo Jiao Liang Wang +9 位作者 Hongyu Ni Haiyan Wang Lanshu Bai Shuo Liu Zhihong Zhang Zhenpeng Yang Zhengdong Cui Qingshan Sun Rui Qian Mengying Li 《Earthquake Science》 2026年第2期220-234,共15页
The Haicheng region,Liaoning,China,likely hosts a conjugate fault system comprising the NW-trending Haichenghe fault and NE-trending secondary faults.On February 4,1975,at 19:36 CST,an earthquake of M_(S)7.3 and inten... The Haicheng region,Liaoning,China,likely hosts a conjugate fault system comprising the NW-trending Haichenghe fault and NE-trending secondary faults.On February 4,1975,at 19:36 CST,an earthquake of M_(S)7.3 and intensity(MMI)IX hit the city of Haicheng,Liaoning,China.Although deep seismic profiling was previously conducted along the Haichenghe fault,the limited horizontal resolution in the shallow part prevented the recognition of kilometer-scale anomalies.The velocity structure characteristics of the Haichenghe fault and its NE-trending conjugate faults remain unclear.Using the extended range phase shift method,the high-resolution S-wave velocity structures are obtained by deploying a long,dense linear array of 55 short-period seismometers across the fault and NE-trending conjugate faults.The array length was 32 km and inter-station spacing was approximately 600 m,facilitating the collection of approximately 22 days of continuous waveform data.Employing the Extended Range Phase Shift(ERPS)method enabled the extraction of broadband 0.2–5 s Rayleigh wave phase velocity dispersion curves.The broadband dispersion data were used for inversion of the high-resolution S-wave velocity structure to a depth of 8 km from the surface.The velocity structure characteristics and seismicity of the Haichenghe fault and NE-trending conjugate faults were analyzed and compared with nearby fault gas measurements.Results show(1)shallow S-wave velocities show a low-high-low horizontal distribution,corresponding to basin-uplift-basin topography;(2)significant velocity contrasts occur across the Haichenghe fault:its SW segment(0–17 km)exhibits high velocities consistent with Paleoproterozoic crystalline basement(Pt_(1)),while the NE segment(17–32 km)shows low velocities related to Yanshanian intrusions(γ_(5))and Quaternary sediments.NE-trending conjugate faults display sharp velocity gradients marking fracture locations,with all faults being near-vertical to~8 km depth;(3)seismicity at 1–6 km depth mainly clusters in high-velocity zones;at 6–8 km depth,it concentrates beneath the Haichenghe fault in low-velocity areas and along NE-trending faults;(4)the seismic activity characteristics and fault zone width of the Haicheng he fault reflected by velocity imaging results are basically consistent with those obtained by the fault gas measurement method. 展开更多
关键词 dense linear array ambient noise tomography extended range phase shift method S-wave velocity structure Haichenghe fault
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A perspective review of applications of the computed tomography(CT)scan imaging technique for microscopic reservoir rock characterization
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作者 Achinta Bera Bharadwaj Shukla Dhruvikkumar Jogani 《Deep Underground Science and Engineering》 2026年第1期4-27,共24页
In hospitals,a medical computed tomography(CT)scan is used to detect damage to infected areas of the human body.Using this technology,scientists and engineers have found a way to detect the internal pore connections a... In hospitals,a medical computed tomography(CT)scan is used to detect damage to infected areas of the human body.Using this technology,scientists and engineers have found a way to detect the internal pore connections and characterize rock samples of oil and gas reservoirs in the petroleum industry.Nowadays,the micro-CT scan technique is gaining considerable interest in reservoir rock characterization and in situ monitoring of fluid flow through porous media during different flooding experiments.Along with this digital rock physics(DRP)idea,images have been used to accurately describe and model for simulations of rock samples.In this review,the application of micro-CT and medical-CT scanning in the oil and gas industry has been thoroughly discussed.Recent improvements in DRP and modern imaging techniques in the oil and gas industry have been modeled using both experimental and simulation work.The combination of a DRP study and a CT scan has also been discussed as a unique idea for the current scenario of research work in this field.The available literature shows that the modern imaging technique and the DRP concept can enable an understanding of the pore network model.It has also been observed that the visualization of fluid flow behavior through porous media is now possible during fluid movement through the core samples.This review contributes to the new research area and aids those in this field in quickly gaining an understanding of applied image techniques in the oil and gas industry. 展开更多
关键词 computed tomography scanning technology digital rock physics multiphase flow oil and gas industry porous media reservoir characterization
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