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Advanced Brain Tumor Segmentation in Magnetic Resonance Imaging via 3D U-Net and Generalized Gaussian Mixture Model-Based Preprocessing
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作者 Khalil Ibrahim Lairedj Zouaoui Chama +5 位作者 Amina Bagdaoui Samia Larguech Younes Menni Nidhal Becheikh Lioua Kolsi Badr M.Alshammari 《Computer Modeling in Engineering & Sciences》 2025年第8期2419-2443,共25页
Brain tumor segmentation from Magnetic Resonance Imaging(MRI)supports neurologists and radiologists in analyzing tumors and developing personalized treatment plans,making it a crucial yet challenging task.Supervised m... Brain tumor segmentation from Magnetic Resonance Imaging(MRI)supports neurologists and radiologists in analyzing tumors and developing personalized treatment plans,making it a crucial yet challenging task.Supervised models such as 3D U-Net perform well in this domain,but their accuracy significantly improves with appropriate preprocessing.This paper demonstrates the effectiveness of preprocessing in brain tumor segmentation by applying a pre-segmentation step based on the Generalized Gaussian Mixture Model(GGMM)to T1 contrastenhanced MRI scans from the BraTS 2020 dataset.The Expectation-Maximization(EM)algorithm is employed to estimate parameters for four tissue classes,generating a new pre-segmented channel that enhances the training and performance of the 3DU-Net model.The proposed GGMM+3D U-Net framework achieved a Dice coefficient of 0.88 for whole tumor segmentation,outperforming both the standard multiscale 3D U-Net(0.84)and MMU-Net(0.85).It also delivered higher Intersection over Union(IoU)scores compared to models trained without preprocessing or with simpler GMM-based segmentation.These results,supported by qualitative visualizations,suggest that GGMM-based preprocessing should be integrated into brain tumor segmentation pipelines to optimize performance. 展开更多
关键词 Magnetic resonance imaging(MRI) imaging technology GGMM EM algorithm 3D U-Net SEGMENTATION
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Dual-frequency angular-multiplexed fringe projection profilometry with deep learning:breaking hardware limits for ultra-high-speed 3D imaging
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作者 Wenwu Chen Yifan Liu +8 位作者 Shijie Feng Wei Yin Jiaming Qian Yixuan Li Hang Zhang Maciej Trusiak Malgorzata Kujawinska Qian Chen Chao Zuo 《Opto-Electronic Advances》 2025年第9期15-24,共10页
Recent advancements in artificial intelligence have transformed three-dimensional(3D)optical imaging and metrology,enabling high-resolution and high-precision 3D surface geometry measurements from one single fringe pa... Recent advancements in artificial intelligence have transformed three-dimensional(3D)optical imaging and metrology,enabling high-resolution and high-precision 3D surface geometry measurements from one single fringe pattern projection.However,the imaging speed of conventional fringe projection profilometry(FPP)remains limited by the native sensor refresh rates due to the inherent"one-to-one"synchronization mechanism between pattern projection and image acquisition in standard structured light techniques.Here,we present dual-frequency angular-multiplexed fringe projection profilometry(DFAMFPP),a deep learning-enabled 3D imaging technique that achieves high-speed,high-precision,and large-depth-range absolute 3D surface measurements at speeds 16 times faster than the sensor's native frame rate.By encoding multi-timeframe 3D information into a single multiplexed image using multiple pairs of dual-frequency fringes,high-accuracy absolute phase maps are reconstructed using specially trained two-stage number-theoretical-based deep neural networks.We validate the effectiveness of DFAMFPP through dynamic scene measurements,achieving 10,000 Hz 3D imaging of a running turbofan engine prototype with only a 625 Hz camera.By overcoming the sensor hardware bottleneck,DFAMFPP significantly advances high-speed and ultra-high-speed 3D imaging,opening new avenues for exploring dynamic processes across diverse scientific disciplines. 展开更多
关键词 3D imaging fringe projection profilometry deep learning multiplex ultra-high-speed
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Fourier lightfield multiview stereoscope for large field-of-view 3D imaging in microsurgical settings
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作者 Clare B.Cook Kevin C.Zhou +8 位作者 Martin Bohlen Mark Harfouche Kanghyun Kim Paul Reamey Julia S.Foust Gregor Horstmeyer Ramana Balla Amey Chaware Roarke Horstmeyer 《Advanced Photonics Nexus》 2025年第4期74-88,共15页
We present the Fourier lightfield multiview stereoscope(FiLM-Scope).This imaging device combines concepts from Fourier lightfield microscopy and multiview stereo imaging to capture high-resolution 3D videos over large... We present the Fourier lightfield multiview stereoscope(FiLM-Scope).This imaging device combines concepts from Fourier lightfield microscopy and multiview stereo imaging to capture high-resolution 3D videos over large fields of view.The FiLM-Scope optical hardware consists of a multicamera array,with 48 individual microcameras,placed behind a high-throughput primary lens.This allows the FiLM-Scope to simultaneously capture 48 unique 12.8 megapixel images of a 28×37 mm field-of-view,from unique angular perspectives over a 21 deg×29 deg range,with down to 22μm lateral resolution.We also describe a self-supervised algorithm to reconstruct 3D height maps from these images.Our approach demonstrates height accuracy down to 11μm.To showcase the utility of our system,we perform tool tracking over the surface of an ex vivo rat skull and visualize the 3D deformation in stretching human skin,with videos captured at up to 100 frames per second.The FiLM-Scope has the potential to improve 3D visualization in a range of microsurgical settings. 展开更多
关键词 3D imaging Fourier light field camera array
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Quasi-optical characterization and preliminary experimental results of electron cyclotron emission imaging on HL-3 tokamak
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作者 Kexi HAN Zhongbing SHI +9 位作者 Xin YU Min JIANG Zengchen YANG Yu ZHOU Yuqi SHEN Weichu DENG Liwen HU Anshu LIANG Peiwan SHI Sen XU 《Plasma Science and Technology》 2025年第6期114-121,共8页
Electron cyclotron emission imaging(ECEI)is a critical diagnostic tool for measuring two-dimensional electron temperature fluctuations.The optical system,a key component of the ECEI diagnostic,determines the spatial r... Electron cyclotron emission imaging(ECEI)is a critical diagnostic tool for measuring two-dimensional electron temperature fluctuations.The optical system,a key component of the ECEI diagnostic,determines the spatial resolution,field of view,and imaging performance of electron temperature fluctuations.In this study,comprehensive laboratory tests and characterizations of the optical system,including the local oscillator(LO)coupling optics and the radio frequency(RF)receiving optics,were conducted to ensure optimal performance during plasma discharge experiments.Laboratory testing of the LO optics revealed that the light intensity at the edge channels reaches 36%of that at the central channels;however,both are sufficient to effectively drive the down-converted mixers.The RF optics focus covers the entire non-harmonic overlap region,corresponding to a normalized plasma minor radius range of ρ=−0.2 to 0.9,and offers three zoom modes:narrow,medium,and wide,with poloidal resolutions of 1.5 cm,1.8 cm,and 2.1 cm,respectively.The characterizations for these zoom modes align well with the optical design specifications.It was observed that the imaging surfaces of all zoom modes are exceptionally flat,indicating high-quality ECEI measurements with excellent spatial resolution.The LO lens,focusing lens,and zoom adjustment lens are capable of remote independent control,which enhances the operational flexibility of the system.Preliminary analyses conducted with the ECEI system successfully captured the two-dimensional structure and spatiotemporal evolution of phenomena such as sawtooth crashes,demonstrating the robust capability of the system to provide valuable insights into plasma dynamics. 展开更多
关键词 electron cyclotron emission imaging optical system quasi-optical characterization HL-3 tokamak sawtooth crash
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基于多标记后延迟时间3D-ASL磁共振成像对成年人各脑区血流量的研究
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作者 朱明 刘松国 +2 位作者 韩广 于秀英 赵蕾 《山东医学高等专科学校学报》 2025年第1期80-82,共3页
三维动脉自旋标记(3D-Arterial spin labeling,3D-ASL)磁共振灌注成像是一种非侵入性、无辐射影像检查技术,越来越多地应用到中枢神经系统疾病的诊断。标记后延迟时间(Post labeling delay,PLD)是3D-ASL磁共振灌注成像的重要参数,因个... 三维动脉自旋标记(3D-Arterial spin labeling,3D-ASL)磁共振灌注成像是一种非侵入性、无辐射影像检查技术,越来越多地应用到中枢神经系统疾病的诊断。标记后延迟时间(Post labeling delay,PLD)是3D-ASL磁共振灌注成像的重要参数,因个体差异或不同疾病状态下血流速度不同,用单一PLD的3D-ASL成像测量的脑血流量(Cerebral blood flow,CBF)会出现增高或减低的现象[1],多个单PLD的ASL被许多研究者证实可在一定程度上减少CBF测值偏差,并通过后处理可以得到其他血流灌注参数,如脑血容量(Cerebral blood volume,CBV)和动脉到达时间(Arterial transit time,ATT)等,从而具有更高的临床价值[2-3]。 展开更多
关键词 多标记后延迟时间 3d-asl CBF值 cCBF值
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磁共振3D-ASL脑灌注成像技术联合DWI在缺血性脑卒中的临床应用
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作者 周岩 《吉林医药学院学报》 2025年第3期196-199,共4页
目的观察磁共振三维动脉自旋标记序列(three-dimensional arterial spin labeling,3D-ASL)脑灌注成像技术联合磁共振弥散加权成像(diffusion weighted imaging,DWI)在缺血性脑卒中诊断中应用效果。方法将2024年1月至8月对收治的缺血性... 目的观察磁共振三维动脉自旋标记序列(three-dimensional arterial spin labeling,3D-ASL)脑灌注成像技术联合磁共振弥散加权成像(diffusion weighted imaging,DWI)在缺血性脑卒中诊断中应用效果。方法将2024年1月至8月对收治的缺血性脑卒中患者50例纳入研究组,并选取同期参加健康体检人群50名纳入对照组,所有参与研究对象均接受磁共振3D-ASL脑灌注成像技术联合DWI检查,统计组间检查结果。结果研究组梗死核心区域脑血流量(cere⁃bral blood flow,CBF)值低于缺血半影区CBF值(P<0.05);研究组患者治疗后相对脑血流量、功能独立性量表评分高于治疗前,P<0.05。结论在缺血性脑卒中患者疾病诊断中采用磁共振3D-ASL脑灌注成像技术联合DWI方法,有助于获得相对精准的诊断数据,值得临床中广泛应用。 展开更多
关键词 磁共振3d-asl脑灌注成像技术 磁共振弥散加权成像 急性脑卒 临床应用
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Magnetic resonance imaging combined with serum endolipin and galactagoglobin-3 to diagnose cerebral infarction in the elderly with diabetes mellitus 被引量:2
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作者 Yan-Hui Zhang Dong Liang 《World Journal of Diabetes》 SCIE 2024年第7期1509-1517,共9页
BACKGROUND Magnetic resonance imaging(MRI)combined with serum endothelin and galactagoglobin-3(Gal-3)can improve the clinical diagnosis of diabetes mellitus complicated with cerebral infarction.AIM To analyze the clin... BACKGROUND Magnetic resonance imaging(MRI)combined with serum endothelin and galactagoglobin-3(Gal-3)can improve the clinical diagnosis of diabetes mellitus complicated with cerebral infarction.AIM To analyze the clinical value of MRI combined with serum endolipin and Gal-3 for the diagnosis of cerebral infarction in the elderly with diabetes mellitus.METHODS One hundred and fifty patients with acute cerebral infarction hospitalized between January 2021 and December 2023 were divided into two groups according to comorbid diabetes mellitus,including 62 and 88 cases in the diabetic and nondiabetic cerebral infarction groups.Serum samples were collected to detect the expression of serum endolipoxins,and Gal-3,and cranial MRI was performed at admission.Differences between the two groups were compared to analyze the diagnostic value of these parameters.RESULTS Serum endolipin and Gal-3 expression were higher in the diabetic cerebral infarction group(P<0.05).The arterial wall area,vessel area,normalized wall index,and lumen stenosis rate were higher in the diabetic cerebral infarction group,while the rate of arterial lumen moderate and severe stenosis was 48.39% higher(36.36%,P<0.05).The percentage of large(29.03%)and multiple infarcts(33.87%)in the diabetic cerebral infarction group was higher(13.64% and 20.45%),and the incidence rate of lacunar infarcts was lower(37.10%vs 65.91%)(P<0.05).The total incidence of arterial plaque in patients in the diabetic cerebral infarction group was 96.77% higher(69.32%),while the incidence of necrotic lipid core plaque was 58.06%higher(26.14%)(P<0.05).Receiver operating characteristic curve analysis was performed to assess the diagnosis utility of these techniques.MRI in combination with serum endoglin and Gal-3 had the highest area under the curve,the Yoden index,sensitivity and specificity(P<0.05).CONCLUSION The expression of serum endolipin and Gal-3 in elderly patients with diabetes mellitus with cerebral infarction showed an elevated trend,and the degree of luminal stenosis was severe.MRI predominantly revealed large and multiple infarct foci.This combined index examination can improve the clinical diagnosis of diabetes mellitus combined with cerebral infarction. 展开更多
关键词 Endolipin GALECTIN-3 Magnetic resonance imaging Elderly Diabetes mellitus Cerebral infarction
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3D-ASL脑灌注成像技术在缺血性脑血管疾病诊断中的实施效果探究
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作者 马凯 芦苇 +1 位作者 张洋 何跃权 《科技与健康》 2025年第6期21-24,共4页
分析在缺血性脑血管疾病诊断中实施3D-动脉自旋标记(arterial spin labeling,ASL)脑灌注成像技术的价值。选择2022年9月-2024年7月中国贵航集团三〇二医院收治的80例缺血性脑血管疾病患者作为研究对象,对患者开展3D-ASL脑灌注成像技术检... 分析在缺血性脑血管疾病诊断中实施3D-动脉自旋标记(arterial spin labeling,ASL)脑灌注成像技术的价值。选择2022年9月-2024年7月中国贵航集团三〇二医院收治的80例缺血性脑血管疾病患者作为研究对象,对患者开展3D-ASL脑灌注成像技术检查,研究对不同年龄患者使用不同标记后延迟时间(PLD)的各个脑区的脑血流量(CBF值),相同PLD的各脑区患侧和对侧CBF值、不同年龄患者各脑区的CBF值。结果显示,当PLD=1.525 s时和PLD=2.525 s时,患者额、顶、颞、枕叶、基底节及小脑半球区域的CBF值,各脑区对侧与患侧CBF值对比,差异有统计学意义(P<0.05)。研究发现,在缺血性脑血管疾病诊断中实施3D-ASL脑灌注成像技术的效果较好,准确率较高,可及时了解患者的脑血流信息,为临床治疗提供支持。由于急诊及配合欠佳患者的病情紧急,检查时可优先选择合适的PLD[45岁及以下患者(1.525 s),45岁以上患者(2.525 s)]。 展开更多
关键词 3d-asl脑灌注成像技术 PLD选择 缺血性脑血管疾病 诊断价值
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颅脑磁共振3D-ASL对急性脑梗死的诊断价值
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作者 徐宝善 《影像研究与医学应用》 2025年第9期60-63,共4页
目的:研究颅脑磁共振三维动脉自旋标记(3D-ASL)对急性脑梗死的诊断价值。方法:选取2023年4月—2024年4月烟台市福山区人民医院收治的疑似急性脑梗死患者60例,所有患者均行常规MRI扫描序列、颅脑磁共振3D-ASL检查,并以临床综合诊断为金标... 目的:研究颅脑磁共振三维动脉自旋标记(3D-ASL)对急性脑梗死的诊断价值。方法:选取2023年4月—2024年4月烟台市福山区人民医院收治的疑似急性脑梗死患者60例,所有患者均行常规MRI扫描序列、颅脑磁共振3D-ASL检查,并以临床综合诊断为金标准,比较常规MRI与3D-ASL对急性脑梗死患者的诊断效能,并应用3D-ASL技术观察患者不同标记后延迟时间(PLD)时脑血流灌注情况。结果:3D-ASL检查急性脑梗死的灵敏度、准确率、阴性预测值均高于常规MRI,差异有统计学意义(P<0.05);3D-ASL检查急性脑梗死的特异度、阳性预测值略高于常规MRI,差异无统计学意义(P>0.05)。急性脑梗死患者PLD为1525 ms和2525 ms时,左右两侧各脑叶的脑血流量(CBF)值比较,差异有统计学意义(P<0.05)。患者经常规MRI扫描未见明显异常,追加扫描3D-ASL时(PLD=1525 ms)可见右侧大脑中动脉供血区域呈现低灌注或右侧大脑半球见大面积低灌注或左侧小脑半球斑片呈高灌注。结论:颅脑磁共振3D-ASL检查可及时发现急性脑梗死患者早期灌注改变及梗死情况,为临床提供准确的脑血流信息,从而为治疗决策是否适合溶栓提供可靠依据。 展开更多
关键词 颅脑磁共振3d-asl 常规MRI扫描序列 急性脑梗死 血流灌注 脑缺血
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Multi-Stage Hierarchical Feature Extraction for Efficient 3D Medical Image Segmentation
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作者 Jion Kim Jayeon Kim Byeong-Seok Shin 《Computers, Materials & Continua》 2025年第6期5429-5443,共15页
Research has been conducted to reduce resource consumption in 3D medical image segmentation for diverse resource-constrained environments.However,decreasing the number of parameters to enhance computational efficiency... Research has been conducted to reduce resource consumption in 3D medical image segmentation for diverse resource-constrained environments.However,decreasing the number of parameters to enhance computational efficiency can also lead to performance degradation.Moreover,these methods face challenges in balancing global and local features,increasing the risk of errors in multi-scale segmentation.This issue is particularly pronounced when segmenting small and complex structures within the human body.To address this problem,we propose a multi-stage hierarchical architecture composed of a detector and a segmentor.The detector extracts regions of interest(ROIs)in a 3D image,while the segmentor performs segmentation in the extracted ROI.Removing unnecessary areas in the detector allows the segmentation to be performed on a more compact input.The segmentor is designed with multiple stages,where each stage utilizes different input sizes.It implements a stage-skippingmechanism that deactivates certain stages using the initial input size.This approach minimizes unnecessary computations on segmenting the essential regions to reduce computational overhead.The proposed framework preserves segmentation performance while reducing resource consumption,enabling segmentation even in resource-constrained environments. 展开更多
关键词 Volumetric segmentation 3D medical images computational resources
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Multidimensional image morphing-fast image-based rendering of open 3D and VR environments
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作者 Simon SEIBT Bastian KUTH +2 位作者 Bartosz von Rymon LIPINSKI Thomas CHANG Marc Erich LATOSCHIK 《虚拟现实与智能硬件(中英文)》 2025年第2期155-172,共18页
Background In recent years,the demand for interactive photorealistic three-dimensional(3D)environments has increased in various fields,including architecture,engineering,and entertainment.However,achieving a balance b... Background In recent years,the demand for interactive photorealistic three-dimensional(3D)environments has increased in various fields,including architecture,engineering,and entertainment.However,achieving a balance between the quality and efficiency of high-performance 3D applications and virtual reality(VR)remains challenging.Methods This study addresses this issue by revisiting and extending view interpolation for image-based rendering(IBR),which enables the exploration of spacious open environments in 3D and VR.Therefore,we introduce multimorphing,a novel rendering method based on the spatial data structure of 2D image patches,called the image graph.Using this approach,novel views can be rendered with up to six degrees of freedom using only a sparse set of views.The rendering process does not require 3D reconstruction of the geometry or per-pixel depth information,and all relevant data for the output are extracted from the local morphing cells of the image graph.The detection of parallax image regions during preprocessing reduces rendering artifacts by extrapolating image patches from adjacent cells in real-time.In addition,a GPU-based solution was presented to resolve exposure inconsistencies within a dataset,enabling seamless transitions of brightness when moving between areas with varying light intensities.Results Experiments on multiple real-world and synthetic scenes demonstrate that the presented method achieves high"VR-compatible"frame rates,even on mid-range and legacy hardware,respectively.While achieving adequate visual quality even for sparse datasets,it outperforms other IBR and current neural rendering approaches.Conclusions Using the correspondence-based decomposition of input images into morphing cells of 2D image patches,multidimensional image morphing provides high-performance novel view generation,supporting open 3D and VR environments.Nevertheless,the handling of morphing artifacts in the parallax image regions remains a topic for future research. 展开更多
关键词 Computer graphics 3D real-time rendering Computer vision image morphing Virtual reality
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基于3D-ASL技术探讨mTBI对人脑持续注意力的影响
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作者 李勃 张书芬 +3 位作者 徐伟林 陈春莲 呼华瑄 刘锴 《中国医疗设备》 2025年第7期133-140,共8页
目的利用三维动脉自旋标记灌注成像(Three Dimensional Arterial Spin Labeling,3D-ASL)及精神运动警觉性实验(Psychomotor Vigilance Test,PVT)探讨轻度脑外伤(Mild Traumatic Brain Injury,mTBI)患者脑持续注意损伤的神经机制。方法纳... 目的利用三维动脉自旋标记灌注成像(Three Dimensional Arterial Spin Labeling,3D-ASL)及精神运动警觉性实验(Psychomotor Vigilance Test,PVT)探讨轻度脑外伤(Mild Traumatic Brain Injury,mTBI)患者脑持续注意损伤的神经机制。方法纳入29例急性期、慢性期mTBI患者及25例健康对照者,采集人口学资料、疲劳评定量表(Fatigue Assessment Index,FAI)、匹斯堡睡眠质量评分量表和爱普沃森睡眠量表得分,以及PVT任务态3D-ASL数据。采用方差分析比较各组被试量表得分,利用配对样本t检验比较急性期组和慢性期组被试量表得分。运用重复测量方差分析比较各组PVT反应时,并运用事后检验进一步统计分析。结果急性期组FAI得分高于慢性期组和对照组,差异有统计学意义(P<0.05),其余比较差异无统计学意义(P>0.05)。PVT行为学显示,反应时存在显著时间主效应(P<0.05),时间和分组具有交互效应(P<0.05)。急性期各阶段反应时均长于对照组(P<0.05)及慢性期组(P<0.05),慢性期组与对照组差异无统计学意义(P>0.05)。脑血流(Cerebral Blood Flow,CBF)变化显示,急性期组:海马旁回、楔前叶CBF下降,额叶、顶叶CBF升高;较对照组,丘脑、额叶及顶下小叶CBF增加,海马旁回、楔前叶CBF降低,差异有统计学意义(P<0.05)。慢性期组:额叶CBF升高,楔前叶、后扣带回CBF下降;较对照组,前扣带回、额中回、额下回CBF升高,楔前叶、顶下小叶CBF降低,差异有统计学意义(P<0.05)。对照组:后扣带回、额中回、辅助运动区和颞上回CBF下降,差异有统计学意义(P<0.05)。结论mTBI患者在受伤后1年内脑持续注意损伤会有所缓解,但仍持续存在。患者在急性期和慢性期脑持续注意能力均受到损害,其中慢性期会有所缓解但仍低于对照组。 展开更多
关键词 三维动脉自旋标记灌注成像(3d-asl) 轻度脑外伤 持续注意 脑血流 功能磁共振 精神运动警觉测试
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1.5T磁共振3D-ASL技术在急性缺血性脑卒中诊断中的应用价值分析
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作者 陈保君 覃建格 杨新超 《当代医药论丛》 2025年第16期127-129,共3页
目的:探究1.5T磁共振3D-ASL技术在急性缺血性脑卒中诊断中的应用价值。方法:选取柳州市融安县人民医院2022年1月至2024年1月收治的31例急性期缺血性脑卒中患者作为观察组,选择同期31例缺血性脑卒中恢复期患者为对照组。两组均采用1.5T... 目的:探究1.5T磁共振3D-ASL技术在急性缺血性脑卒中诊断中的应用价值。方法:选取柳州市融安县人民医院2022年1月至2024年1月收治的31例急性期缺血性脑卒中患者作为观察组,选择同期31例缺血性脑卒中恢复期患者为对照组。两组均采用1.5T磁共振3D-ASL技术进行诊断,分析比较其诊断结果。结果:两组脑梗死病灶区、缺血半暗带区、镜面区局部脑血流量(rCBF)对比差异显著(P<0.05)。两组脑梗死病灶区、缺血半暗带区表观扩散系数(ADC)对比差异显著(P<0.05)。观察组病灶平均体积显著大于对照组(P<0.05)。结论:在急性缺血性脑卒中的诊断中,1.5T磁共振3D-ASL技术具有良好的诊断效能。 展开更多
关键词 急性缺血性脑卒中 1.5T磁共振3d-asl技术 局部脑血流量 表观扩散系数
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Efficient single-pixel imaging encrypted transmission based on 3D Arnold transformation
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作者 梁振宇 王朝瑾 +4 位作者 王阳阳 高皓琪 朱东涛 许颢砾 杨星 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期378-386,共9页
Single-pixel imaging(SPI)can transform 2D or 3D image data into 1D light signals,which offers promising prospects for image compression and transmission.However,during data communication these light signals in public ... Single-pixel imaging(SPI)can transform 2D or 3D image data into 1D light signals,which offers promising prospects for image compression and transmission.However,during data communication these light signals in public channels will easily draw the attention of eavesdroppers.Here,we introduce an efficient encryption method for SPI data transmission that uses the 3D Arnold transformation to directly disrupt 1D single-pixel light signals and utilizes the elliptic curve encryption algorithm for key transmission.This encryption scheme immediately employs Hadamard patterns to illuminate the scene and then utilizes the 3D Arnold transformation to permutate the 1D light signal of single-pixel detection.Then the transformation parameters serve as the secret key,while the security of key exchange is guaranteed by an elliptic curve-based key exchange mechanism.Compared with existing encryption schemes,both computer simulations and optical experiments have been conducted to demonstrate that the proposed technique not only enhances the security of encryption but also eliminates the need for complicated pattern scrambling rules.Additionally,this approach solves the problem of secure key transmission,thus ensuring the security of information and the quality of the decrypted images. 展开更多
关键词 single-pixel imaging 3D Arnold transformation elliptic curve encryption image encryption
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Geant4 simulation of fast-electron bremsstrahlung imaging at the HL-3 tokamak
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作者 Shi-Kui Cheng Yi-Po Zhang +4 位作者 Yue-Jiang Shi Jie Zhang Shuai Guan Hong-Bing Xu Qiu-Lei Yang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第9期213-229,共17页
To further research on high-parameter plasma,we plan to develop a two-dimensional hard X-ray(HXR)imaging system at the HL-3 tokamak to measure HXRs with energies ranging from 20 to 300 keV.The application of an array-... To further research on high-parameter plasma,we plan to develop a two-dimensional hard X-ray(HXR)imaging system at the HL-3 tokamak to measure HXRs with energies ranging from 20 to 300 keV.The application of an array-structured detector ensures that this system can measure HXR-radiation spectra from the entire plasma cross section.Therefore,it is suitable for the study of fast-electron physics,such as radio-frequency wave current drives,fast electrons driving instabilities,and plasma disruptions in fusion research.In this study,we develop a simulation for calculating fast-electron bremsstrahlung in the HL-3 tokamak based on the Monte Carlo simulation code Geant4,in which the plasma geometry and forward scattering of fast-electron bremsstrahlung are considered.The preliminary calculation results indicate that the HXR energy deposi-tion on the detector is symmetrically distributed,even though the plasma distribution is asymmetric owing to the toroidal effect.These simulation results are helpful in constructing the relationship between the energy deposition on the detector and parameter distribution on the plasma cross section during HL-3 experiments.This is beneficial for the reconstruction of the fast-electron-distribution function and for optimizing the design of the HXR-imaging system. 展开更多
关键词 GEANT4 SIMULATION HL-3 TOKAMAK Fast-electron bremsstrahlung Hard X-ray imaging
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MACS-W:A modified optical clearing agent for imaging 3D cell cultures
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作者 Xiang Zhong Chao Gao +6 位作者 Hui Li Yuening He Peng Fei Zaozao Chen Zhongze Gu Dan Zhu Tingting Yu 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第2期24-34,共11页
Three-dimensional(3D)cell cultures have contributed to a variety of biological research fields by filling the gap between monolayers and animal models.The modern optical sectioning microscopic methods make it possible... Three-dimensional(3D)cell cultures have contributed to a variety of biological research fields by filling the gap between monolayers and animal models.The modern optical sectioning microscopic methods make it possible to probe the complexity of 3D cell cultures but are limited by the inherent opaqueness.While tissue optical clearing methods have emerged as powerful tools for investigating whole-mount tissues in 3D,they often have limitations,such as being too harsh for fragile 3D cell cultures,requiring complex handling protocols,or inducing tissue deformation with shrinkage or expansion.To address this issue,we proposed a modified optical clearing method for 3D cell cultures,called MACS-W,which is simple,highly efficient,and morphology-preserving.In our evaluation of MACS-W,we found that it exhibits excellent clearing capability in just 10 min,with minimal deformation,and helps drug evaluation on tumor spheroids.In summary,MACS-W is a fast,minimally-deformative and fluorescence compatible clearing method that has the potential to be widely used in the studies of 3D cell cultures. 展开更多
关键词 Tissue optical clearing 3D cell cultures imaging
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Luminescent terphen[3]arene sulfate-activated FRET assemblies for cell imaging
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作者 Zhixue Liu Haiqi Chen +5 位作者 Lijuan Guo Xinyao Sun Zhi-Yuan Zhang Junyi Chen Ming Dong Chunju Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第9期183-186,共4页
Multicharged supramolecular assemblies based on luminescent macrocycle play an important role in extending their optical properties and functions.Herein,we reported macrocyclic supramolecular assemblies based on lumin... Multicharged supramolecular assemblies based on luminescent macrocycle play an important role in extending their optical properties and functions.Herein,we reported macrocyclic supramolecular assemblies based on luminescent terphen[3]arene sulfate(TP[3]AS)and tetraphenylethylene pyridinium(TPE-4Py)through electrostatic interactions,host-vip encapsulation andπ-πstacking interactions.F?rster resonance energy transfer(FRET)process from TP[3]AS to TPE-4Py was achieved with the energy transfer efficiency of 99.9%,accompanied by TPE-4Py fluorescence emission bathochromic shifted of 15 nm and enhanced by 1.68 times in PBS solution.In contrast,other non-luminescent sulfato-β-cyclodextrin and sulfobutylether-β-cyclodextrin only can enhance the fluorescence intensity of TPE-4Py without bathochromic shift.Due to the strong fluorescence and good stability of TPE-4Py@TP[3]AS,it can be used for optical imaging in living cells,which provided an effective approach for the construction of assembling-confined luminescent biomaterials. 展开更多
关键词 Luminescent macrocycle arene sulfate Multicharged assembly Multivalent interactions Forster resonance energy transfer Cell imaging
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Non-invasively differentiate non-alcoholic steatohepatitis by visualizing hepatic integrin αvβ3 expression with a targeted molecular imaging modality
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作者 Xiao-Quan Huang Ling Wu +7 位作者 Chun-Yan Xue Chen-Yi Rao Qing-Qing Fang Ying Chen Cao Xie Sheng-Xiang Rao Shi-Yao Chen Feng Li 《World Journal of Hepatology》 2024年第11期1290-1305,共16页
BACKGROUND Non-invasive methods to diagnose non-alcoholic steatohepatitis(NASH),an inflammatory subtype of non-alcoholic fatty liver disease(NAFLD),are currently unavailable.AIM To develop an integrin αvβ3-targeted ... BACKGROUND Non-invasive methods to diagnose non-alcoholic steatohepatitis(NASH),an inflammatory subtype of non-alcoholic fatty liver disease(NAFLD),are currently unavailable.AIM To develop an integrin αvβ3-targeted molecular imaging modality to differentiate NASH.METHODS Integrinαvβ3 expression was assessed in Human LO2 hepatocytes Scultured with palmitic and oleic acids(FFA).Hepatic integrinαvβ3 expression was analyzed in rabbits fed a high-fat diet(HFD)and in rats fed a high-fat,high-carbohydrate diet(HFCD).After synthesis,cyclic arginine-glycine-aspartic acid peptide(cRGD)was labeled with gadolinium(Gd)and used as a contrast agent in magnetic resonance imaging(MRI)performed on mice fed with HFCD.RESULTS Integrin αvβ3 was markedly expressed on FFA-cultured hepatocytes,unlike the control hepatocytes.Hepatic integrin αvβ3 expression significantly increased in both HFD-fed rabbits and HFCD-fed rats as simple fatty liver(FL)progressed to steatohepatitis.The distribution of integrinαvβ3 in the liver of NASH cases largely overlapped with albumin-positive staining areas.In comparison to mice with simple FL,the relative liver MRI-T1 signal value at 60 minutes post-injection of Gd-labeled cRGD was significantly increased in mice with steatohepatitis(P<0.05),showing a positive correlation with the NAFLD activity score(r=0.945;P<0.01).Hepatic integrin αvβ3 expression was significantly upregulated during NASH development,with hepatocytes being the primary cells expressing integrin αvβ3.CONCLUSION After using Gd-labeled cRGD as a tracer,NASH was successfully distinguished by visualizing hepatic integrin αvβ3 expression with MRI. 展开更多
关键词 Non-alcoholic steatohepatitis Cyclic peptides Magnetic resonance imaging Non-invasive diagnosis Hepatic integrinαvβ3
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Anion photoelectron imaging and theoretical study of Cu(CO)_(3)^(-)
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作者 Zhen Li Wenli Liu +4 位作者 Gaoming Hu Boxing Zhu Qiang Zhang Yang Chen Dongfeng Zhao 《Chinese Journal of Chemical Physics》 CSCD 2024年第6期777-782,I0042,共7页
Photoelectron velocity map images of Cu(CO)_(3)^(-)have been experimentally recorded in the 700-1100 nm range.The infrared-inactive Cu^(-)C symmetric stretching modes for Cu(CO)_(3)(v_(2)≈367 cm^(-1))and Cu(CO)_(3)^(... Photoelectron velocity map images of Cu(CO)_(3)^(-)have been experimentally recorded in the 700-1100 nm range.The infrared-inactive Cu^(-)C symmetric stretching modes for Cu(CO)_(3)(v_(2)≈367 cm^(-1))and Cu(CO)_(3)^(-)(v_(2)≈408 cm^(-1)),as well as the electron affinity(1.03±0.11 eV)of Cu(CO)_(3),are accurately determined from high resolution photoelectron spectra.In combination with quantum chemical calculations and bonding analyses,the coordination bonds in both Cu(CO)_(3)^(-)are Cu(CO)_(3)are found to be due to back-donationπbonding type,formed via electron promotion from Cu’s 4s orbital to the 4p orbital,which is consequently donated to the unoccupied anti-bondingπ*orbitals of the carbonyl groups.The attachment of an additional electron to Cu(CO)_(3)strengthens the Cu^(-)CO coordination,making Cu(CO)_(3)^(-)more stable.The intramolecular interactions between the Cu/Cu^(-)and carbonyl groups are found to be primarily governed by electrostatic forces and orbital interactions. 展开更多
关键词 Cu(CO)_(3)^(-) Photoelectron imaging Coordination bond
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The Application Value of Ultrasound Imaging in the Differential Diagnosis of Benign and Malignant Breast Nodules of BI-RADS 3 and Above
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作者 Dongmei Chen 《Proceedings of Anticancer Research》 2024年第2期53-58,共6页
Objective:To explore the diagnostic value of ultrasound imaging for breast nodules of breast imaging-reporting and data system(BI-RADS)category 3 and above.Methods:From June 2021 to July 2022,163 patients with breast ... Objective:To explore the diagnostic value of ultrasound imaging for breast nodules of breast imaging-reporting and data system(BI-RADS)category 3 and above.Methods:From June 2021 to July 2022,163 patients with breast nodules of BI-RADS 3 or above were selected as the research subjects.After pathological diagnosis,24 cases were malignant breast nodules of BI-RADS 3 or above,while 139 cases were benign breast nodules of BI-RADS 3 or above.The diagnosis rate of malignant and benign breast nodules of BI-RADS 3 or above,including 95%CI,was observed and analyzed.Results:The malignant and benign detection rates of conventional ultrasound were 88.63%and 75.00%,respectively,and the malignant and benign detection rates of ultrasound imaging were 93.18%and 87.50%,respectively,with 95%CIs greater than 0.7.Conclusion:Ultrasound imaging can help improve the diagnostic accuracy of benign and malignant breast nodules of BI-RADS 3 and above and reduce the misdiagnosis rate. 展开更多
关键词 ULTRASOUND Ultrasound imaging Breast imaging-reporting and data system(BI-RADS)category 3 and above Diagnosis
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