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MOVING OBJECT TRACKING IN DYNAMIC IMAGE SEQUENCE BASED ON ESTIMATION OF MOTION VECTORS OF FEATURE POINTS 被引量:2
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作者 黎宁 周建江 张星星 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第4期295-300,共6页
An improved estimation of motion vectors of feature points is proposed for tracking moving objects of dynamic image sequence. Feature points are firstly extracted by the improved minimum intensity change (MIC) algor... An improved estimation of motion vectors of feature points is proposed for tracking moving objects of dynamic image sequence. Feature points are firstly extracted by the improved minimum intensity change (MIC) algorithm. The matching points of these feature points are then determined by adaptive rood pattern searching. Based on the random sample consensus (RANSAC) method, the background motion is finally compensated by the parameters of an affine transform of the background motion. With reasonable morphological filtering, the moving objects are completely extracted from the background, and then tracked accurately. Experimental results show that the improved method is successful on the motion background compensation and offers great promise in tracking moving objects of the dynamic image sequence. 展开更多
关键词 motion compensation motion estimation feature extraction moving object tracking dynamic image sequence
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A framework of region-based dynamic image fusion 被引量:1
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作者 WANG Zhong-hua QIN Zheng LIU Yu 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第1期56-62,共7页
A new framework of region-based dynamic image fusion is proposed. First, the technique of target detection is applied to dynamic images (image sequences) to segment images into different targets and background regions... A new framework of region-based dynamic image fusion is proposed. First, the technique of target detection is applied to dynamic images (image sequences) to segment images into different targets and background regions. Then different fusion rules are employed in different regions so that the target information is preserved as much as possible. In addition, steerable non-separable wavelet frame transform is used in the process of multi-resolution analysis, so the system achieves favorable characters of orientation and invariant shift. Compared with other image fusion methods, experimental results showed that the proposed method has better capabilities of target recognition and preserves clear background information. 展开更多
关键词 dynamic image fusion Region segmentation Non-separable wavelet frame
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Discrete-Time Dynamic Image Segmentation Using Oscillators with Adaptive Coupling
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作者 Mio Kobayashi Tetsuya Yoshinaga 《International Journal of Modern Nonlinear Theory and Application》 2016年第2期93-103,共11页
In this study, we propose a novel discrete-time coupled model to generate oscillatory responses via periodic points with a high periodic order. Our coupled system comprises one-dimensional oscillators based on the Rul... In this study, we propose a novel discrete-time coupled model to generate oscillatory responses via periodic points with a high periodic order. Our coupled system comprises one-dimensional oscillators based on the Rulkov map and a single globally coupled oscillator. Because the waveform of a one-dimensional oscillator has sharply defined peaks, the coupled system can be applied to dynamic image segmentation. Our proposed system iteratively transforms the coupling of each oscillator based on an input value that corresponds to the pixel value of an input image. This approach enables our system to segment image regions in which pixel values gradually change with respect to a connected region. We conducted a bifurcation analysis of a single oscillator and a three-coupled model. Through simulations, we demonstrated that our system works well for gray-level images with three isolated image regions. 展开更多
关键词 Discrete-Time Coupled Model dynamic image Segmentation Oscillatory Responses One-Dimensional Oscillator
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Fabric Wetting and Wicking Measurement Based on Dynamic Image Acquisition and Processing 被引量:1
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作者 张瑞云 潘宁 姜福青 《Journal of Donghua University(English Edition)》 EI CAS 2010年第4期544-550,共7页
After a brief review of existing methods for fabric wetting and wicking measurement,a new numerical approach based on dynamic image acquisition and analysis was proposed to study the liquid wetting and wicking propert... After a brief review of existing methods for fabric wetting and wicking measurement,a new numerical approach based on dynamic image acquisition and analysis was proposed to study the liquid wetting and wicking properties of woven fabrics.A measuring system was first developed to record on-site the images of liquid ascending in fabrics for a certain period of time.The hardware and software platforms and the experimental methods were described,and the image processing and analysis as well as other related algorithms were discussed in detail.The liquid front curves and rising rates in wetting and wicking were eventually obtained towards different fabrics.From liquid wicking curves,relationship between liquid ascending height and liquid ascending time agrees well with the Washburn theory.The data comparison between the numerical measurement and the traditional test proves the reliability of the numerical results. 展开更多
关键词 wetting and wicking image processing woven fabric image dynamic acquisition
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Application of dynamic image analysis to the optical characterisation of fibrous bulk material
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作者 Johannes Lunewski Eberhard Schmidt 《Particuology》 SCIE EI CAS CSCD 2024年第7期51-60,共10页
Dynamic image analysis provides an automated evaluation method to determine the size and shape of multiple particles. This method represents a common application for ordinary bulk material. The latest draft of ISO 13... Dynamic image analysis provides an automated evaluation method to determine the size and shape of multiple particles. This method represents a common application for ordinary bulk material. The latest draft of ISO 13322–2:2021 describes the state of the art, but lacks instructions for handling fibrous bulk material. Interlocking fibres complicate the measurement conditions and require a disentanglement of fibrous samples during a pre-dispersion step. A further error source includes the fibre orientation inside the measurement zone of the device. If the thresholding algorithm fails to differentiate between the fibre projection area and the background, a subsequent image optimisation solves the problem. This article addresses the mentioned problems by analysing cotton cellulose and polyacrylonitrile fibres. Besides the execution of a pre-dispersion step, the experiments compare the discrepancies between dry and wet dispersion. Here, the software packages PAQXOS and ImageJ perform the image evaluation. In this case, the wet dispersion setup with a subsequent image evaluation by ImageJ provides comprehensible results. 展开更多
关键词 Bootstrap method dynamic image analysis Fibre diameter Fibre length distribution Natural fibres Synthetic fibres
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Dynamic Visual Image Modeling Based on Mobile RobotSelf- Organizing Network in Internetof Things Perception Layer 被引量:1
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作者 高立 任旭鹏 李晓博 《China Communications》 SCIE CSCD 2011年第8期49-55,共7页
The dynamic multichannel binocular visual image modeling is studied based on Internet of Things (IoT) Perception Layer, using mobile robot self-organizing network. By employing multigroup mobile robots with binocular ... The dynamic multichannel binocular visual image modeling is studied based on Internet of Things (IoT) Perception Layer, using mobile robot self-organizing network. By employing multigroup mobile robots with binocular visual system, the real visual images of the object will be obtained. Then through the mobile self-organizing network, a three-dimensional model is rebuilt by synthesizing the returned images. On this basis, we formalize a novel algorithm for multichannel binocular visual three-dimensional images based on fast three-dimensional modeling. Compared with the method based on single binocular visual system, the new algorithm can improve the Integrity and accuracy of the dynamic three-dimensional object modeling. The simulation results show that the new method can effectively accelerate the modeling speed, improve the similarity and not increase the data size. 展开更多
关键词 IoT perception layer multigroup binocular visual dynamic visual image modeling fast three-dimensional modeling rebuild
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In situ nanobubble sizing by visualization particle tracking and image-based dynamic light scattering 被引量:1
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作者 Yang Li Ma Yinhang +5 位作者 Jin Juan Yang Fujun Yang Fang Huang Bin Li Yan Gu Ning 《Journal of Southeast University(English Edition)》 EI CAS 2021年第3期237-244,共8页
A novel method combining visualization particle tracking with image-based dynamic light scattering was developed to achieve the in situ and real-time size measurement of nanobubbles(NBs).First,the in situ size distrib... A novel method combining visualization particle tracking with image-based dynamic light scattering was developed to achieve the in situ and real-time size measurement of nanobubbles(NBs).First,the in situ size distribution of NBs was visualized by dark-field microscopy.Then,real-time size during the preparation was measured using image-based dynamic light scattering,and the longitudinal size distribution of NBs in the sample cell was obtained in a steady state.Results show that this strategy can provide a detailed and accurate size of bubbles in the whole sample compared with the commercial ZetaSizer Nano equipment.Therefore,the developed method is a real-time and simple technology with excellent accuracy,providing new insights into the accurate measurement of the size distribution of NBs or nanoparticles in solution. 展开更多
关键词 real-time acquisition nanobubble(NB)sizing visualization particle tracking image dynamic light scattering Brownian motion
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Distortion-Free Data Embedding Scheme for High Dynamic Range Images
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作者 Chin-Chen Chang Thai-Son Nguyen Chia-Chen Lin 《Journal of Electronic Science and Technology》 CAS 2013年第1期20-26,共7页
Distortion-free data embedding is a technique which can assure that not only the secret data is correctly extracted but also the cover media is recovered without any distortion after secret data is extracted completel... Distortion-free data embedding is a technique which can assure that not only the secret data is correctly extracted but also the cover media is recovered without any distortion after secret data is extracted completely. Because of these advantages, this technique attracts the attention of many researchers. In this paper, a new distortion-free data embedding scheme for high dynamic range (HDR) images is proposed. By depending on Cartesian product, this scheme can obtain higher embedding capacity while maintaining the exactly identical cover image and stego image when using the tone mapping algorithms. In experimental results, the proposed scheme is superior to Yu et aL's scheme in regard to the embedding rate——an average embedding rate of 0.1355 bpp compared with Yn et aL's scheme (0.1270 bpp). 展开更多
关键词 Data hiding distortion free high dynamic range image high embedding rate stegano-graphy.
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Shape recovery using high dynamic range images
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作者 郑作勇 Ma Lizhuang Li Zhong 《High Technology Letters》 EI CAS 2008年第4期384-389,共6页
An effective method for object shape recovery using HDRIs (high dynamic range images) is proposed. The radiance values of each point on the reference sphere and target object are firstly calculated, thus the set of ... An effective method for object shape recovery using HDRIs (high dynamic range images) is proposed. The radiance values of each point on the reference sphere and target object are firstly calculated, thus the set of candidate normals of each target point are found by comparing its radiance to that of each reference sphere point. In single-image shape recovery, a smoothness operation is applied to the target normals to obtain a stable and reasonable result; while in photometric stereo, radiance vectors of reference and target objects formed due to illuminations under different fight source directions are directly compared to get the most suitable target normals. Finally, the height values can be recovered from the resulting normal field. Because diffuse and specular reflection are handled in an unified framework with radiance, our approach eliminates the limitation presented in most recovery strategies, i.e., only Lambertian model can be used. The experiment results from the real and synthesized images show the performance of our approach. 展开更多
关键词 shape recovery high dynamic range image bidirectional reflectance distribution function (BRDF) reflectance map photometric stereo
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Emotionally Resonant Branding: The Role of AI in Synthesising Dynamic Brand Images for Artists in the Music Industry
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作者 Kaveen Prabodhya Thivanka Liyanage Weliweriya Liyanage Himendra Balalle 《Open Journal of Applied Sciences》 2024年第9期2661-2678,共18页
Artificial Intelligence (AI) expands its recognition rapidly through the past few years in the context of generating content dynamically, remarkably challenging the human creativity. This study aims to evaluate the ef... Artificial Intelligence (AI) expands its recognition rapidly through the past few years in the context of generating content dynamically, remarkably challenging the human creativity. This study aims to evaluate the efficacy of AI in enhancing personal branding for musicians, particularly in crafting brand images based on emotions received from the artist’s music will improve the audience perceptions regarding the artist’s brand. Study used a quantitative approach for the research, gathering primary data from the survey of 191 people—music lovers, musicians and music producers. The survey focuses on preferences, perceptions, and behaviours related to music consumption and artist branding. The study results demonstrate the awareness and understanding of AI’s role in personal branding within the music industry. Also, results indicate that such an adaptive approach enhances audience perceptions of the artist and strengthens emotional connections. Furthermore, over 50% of the participants indicated a desire to attend live events where an artist’s brand image adapts dynamically to their emotions. The study focuses on novel approaches in personal branding based on the interaction of AI-driven emotional data. In contrast to traditional branding concepts, this study indicates that AI can suggest dynamic and emotionally resonant brand identities for artists. The real time audience response gives proper guidance for the decision-making. This study enriches the knowledge of AI’s applicability to branding processes in the context of the music industry and opens the possibilities for additional advancements in building emotionally appealing brand identities. 展开更多
关键词 Artificial Intelligence Emotional Branding Personal Branding Music Industry dynamic Brand image Audience Perception Machine Learning Real-Time Emotional Responses
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Star point positioning for large dynamic star sensors in near space based on capsule network
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作者 Zhen LIAO Hongyuan WANG +3 位作者 Xunjiang ZHENG Yunzhao ZANG Yinxi LU Shuai YAO 《Chinese Journal of Aeronautics》 2025年第2期418-431,共14页
In order to solve the problem that the star point positioning accuracy of the star sensor in near space is decreased due to atmospheric background stray light and rapid maneuvering of platform, this paper proposes a s... In order to solve the problem that the star point positioning accuracy of the star sensor in near space is decreased due to atmospheric background stray light and rapid maneuvering of platform, this paper proposes a star point positioning algorithm based on the capsule network whose input and output are both vectors. First, a PCTL (Probability-Coordinate Transformation Layer) is designed to represent the mapping relationship between the probability output of the capsule network and the star point sub-pixel coordinates. Then, Coordconv Layer is introduced to implement explicit encoding of space information and the probability is used as the centroid weight to achieve the conversion between probability and star point sub-pixel coordinates, which improves the network’s ability to perceive star point positions. Finally, based on the dynamic imaging principle of star sensors and the characteristics of near-space environment, a star map dataset for algorithm training and testing is constructed. The simulation results show that the proposed algorithm reduces the MAE (Mean Absolute Error) and RMSE (Root Mean Square Error) of the star point positioning by 36.1% and 41.7% respectively compared with the traditional algorithm. The research results can provide important theory and technical support for the scheme design, index demonstration, test and evaluation of large dynamic star sensors in near space. 展开更多
关键词 Star point positioning Star trackers Capsule network Deep learning dynamic imaging Near space application
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Super-resolution imaging of cellular pseudopodia dynamics with a target-specific blinkogenic probe
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作者 Aoxuan Song Qinglong Qiao +4 位作者 Ning Xu Yiyan Ruan Wenhao Jia Xiang Wang Zhaochao Xu 《Chinese Chemical Letters》 2025年第8期424-428,共5页
Monitoring the dynamics of cellular pseudopodia at nanoscale has become essential for understanding their diverse and complex functions in living cells.This is made possible by combining single-molecule localization m... Monitoring the dynamics of cellular pseudopodia at nanoscale has become essential for understanding their diverse and complex functions in living cells.This is made possible by combining single-molecule localization microscopy(SMLM)with self-blinking dyes.However,existing self-blinking dyes often face limitations,such as nonspecific blinking and low photostability,which can bring background noise and yield erroneous localization signals,hindering their effectiveness for nanoscale visualization.Here,we present a method for long-term SMLM imaging of cellular pseudopodia dynamics using a blinkogenic probe that exhibits self-blinking activation upon molecular recognition.This approach enabled the precise tracking of various pseudopodia structures,including filopodia,lamellipodia,and(tunneling nanotubes)-nanoscale(TNTs),in living cells.We monitored the growth and fusion of filopodia,as well as the extension and shrinkage of lamellipodia,in real-time.Additionally,we identified two distinct fusion modes between filopodia and lamellipodia and captured the formation of TNTs and their interactions with filopodia,demonstrating the probe's utility in visualizing real-time pseudopodia dynamics at nanoscale. 展开更多
关键词 Single-molecule localization microscopy Cellular pseudopodia Self-blinking Blinkogenic probe dynamic super-resolution imaging
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Deep learning-enhanced NIR-II fluorescence volumetric microscopy for dynamic 3D vascular imaging
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作者 Shiyi Peng Yuhuang Zhang +3 位作者 Xuanjie Mou Tianxiang Wu Mingxi Zhang Jun Qian 《Journal of Innovative Optical Health Sciences》 2025年第3期154-164,共11页
Three-dimensional (3D) visualization of dynamic biological processes in deep tissue remains challenging due to the trade-off between temporal resolution and imaging depth. Here, we present a novel near-infrared-II (NI... Three-dimensional (3D) visualization of dynamic biological processes in deep tissue remains challenging due to the trade-off between temporal resolution and imaging depth. Here, we present a novel near-infrared-II (NIR-II, 900–1880nm) fluorescence volumetric microscopic imaging method that combines an electrically tunable lens (ETL) with deep learning approaches for rapid 3D imaging. The technology achieves volumetric imaging at 4.2 frames per second (fps) across a 200 μm depth range in live mouse brain vasculature. Two specialized neural networks are utilized: a scale-recurrent network (SRN) for image enhancement and a cerebral vessel interpolation (CVI) network that enables 16-fold axial upsampling. The SRN, trained on two-photon fluorescence microscopic data, improves both lateral and axial resolution of NIR-II fluorescence wide-field microscopic images. The CVI network, adapted from video interpolation techniques, generates intermediate frames between acquired axial planes, resulting in smooth and continuous 3D vessel reconstructions. Using this integrated system, we visualize and quantify blood flow dynamics in individual vessels and are capable of measuring blood velocity at different depths. This approach maintains high lateral resolution while achieving rapid volumetric imaging, and is particularly suitable for studying dynamic vascular processes in deep tissue. Our method demonstrates the potential of combining optical engineering with artificial intelligence to advance biological imaging capabilities. 展开更多
关键词 NIR-II fluorescence bioimaging volumetric microscopy deep learning reconstruction dynamic vascular imaging
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Noninvasive prediction of microsatellite instability in stage II/III rectal cancer using dynamic contrast-enhanced magnetic resonance imaging radiomics
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作者 Chao-Yang Zheng Jia-Min Zhang +4 位作者 Qian-Sen Lin Tao Lian Liang-Pan Shi Jie-Yun Chen Ya-Li Cai 《World Journal of Gastrointestinal Oncology》 2025年第8期156-166,共11页
BACKGROUND Colorectal cancer stands among the most prevalent digestive system malignancies.The microsatellite instability(MSI)profile plays a crucial role in determining patient outcomes and therapy responsiveness.Tra... BACKGROUND Colorectal cancer stands among the most prevalent digestive system malignancies.The microsatellite instability(MSI)profile plays a crucial role in determining patient outcomes and therapy responsiveness.Traditional MSI evaluation methods require invasive tissue sampling,are lengthy,and can be compromised by intratumoral heterogeneity.AIM To establish a non-invasive technique utilizing dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)radiomics and machine learning algorithms to determine MSI status in patients with intermediate-stage rectal cancer.METHODS This retrospective analysis examined 120 individuals diagnosed with stage II/III rectal cancer[30 MSI-high(MSI-H)and 90 microsatellite stability(MSS)/MSI-low(MSI-L)cases].We extracted comprehensive radiomics signatures from DCE-MRI scans,encompassing textural parameters that reflect tumor heterogeneity,shapebased metrics,and histogram-derived statistical values.Least absolute shrinkage and selection operator regression facilitated feature selection,while predictive frameworks were developed using various classification algorithms(logistic regression,support vector machine,and random forest).Performance assessment utilized separate training and validation cohorts.RESULTS Our investigation uncovered distinctive imaging characteristics between MSI-H and MSS/MSI-L neoplasms.MSIH tumors exhibited significantly elevated entropy values(7.84±0.92 vs 6.39±0.83,P=0.004),enhanced surface-tovolume proportions(0.72±0.14 vs 0.58±0.11,P=0.008),and heightened signal intensity variation(3642±782 vs 2815±645,P=0.007).The random forest model demonstrated superior classification capability with area under the curves(AUCs)of 0.891 and 0.896 across training and validation datasets,respectively.An integrated approach combining radiomics with clinical parameters further enhanced performance metrics(AUC 0.923 and 0.914),achieving 88.5%sensitivity alongside 87.2%specificity.CONCLUSION DCE-MRI radiomics features interpreted through machine learning frameworks offer an effective strategy for MSI status assessment in intermediate-stage rectal cancer. 展开更多
关键词 dynamic contrast-enhanced magnetic resonance imaging Radiomics Machine learning Rectal cancer Microsatellite instability
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Comparison of dynamic contrast-enhanced-magnetic resonance imaging parameters and serum markers in preoperative rectal cancer evaluation:Combined diagnostic value
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作者 Qun Wang Xin-Yu Zhang +1 位作者 Jing-Fei Yang Yi-Lei Tao 《World Journal of Gastrointestinal Oncology》 2025年第5期148-159,共12页
BACKGROUND Rectal cancer requires accurate preoperative assessment of T stage and differentiation grade for treatment planning.Traditional imaging and serum markers have limitations in diagnostic accuracy.AIM To evalu... BACKGROUND Rectal cancer requires accurate preoperative assessment of T stage and differentiation grade for treatment planning.Traditional imaging and serum markers have limitations in diagnostic accuracy.AIM To evaluate the predictive value of dynamic contrast-enhanced-magnetic resonance imaging(DCE-MRI)parameters and serum biomarkers[carbohydrate antigen(CA)19-9,CA125]for determining T stage and differentiation grade in rectal cancer.METHODS We conducted a retrospective review of clinical data from 126 patients who were pathologically diagnosed with rectal cancer between January 2021 to June 2024.Each patient underwent DCE-MRI scans and serum tests for CA19-9 and CA125.Receiver operating characteristic curves were utilized to assess the diagnostic value of DCE-MRI parameters,including volume transfer constant(Ktrans),rate constant(Kep),and volume fraction of extravascular extracellular space(Ve),as well as serum biomarkers for staging and grading rectal cancer.The DeLong test algorithm was employed to evaluate differences in diagnostic performance among the various indicators.RESULTS There were statistically higher levels of Ktrans,Ve,CA19-9,and CA125 serum concentrations of patients with advanced T stages and on poorly differentiated tumors than that in patients with low stages and moderate to high differentiation(P<0.05).Combined use of Ktrans and Ve for T stage diagnosis showed an area under the curve(AUC)of 0.892[95%confidence interval(CI):0.832-0.952],which increased to 0.923(95%CI:0.865-0.981)when combined with serum biomarkers.For grades differentiation,the combined DCE-MRI parameters had an AUC of 0.883(95%CI:0.821-0.945),which rose to 0.912(95%CI:0.855-0.969)when combined with serum markers.According to the Delong test,the combined diagnostic method performed better than a single diagnostic method(P<0.05).CONCLUSION The combined application of DCE-MRI functional parameters and serum tumor markers can significantly improve the diagnostic accuracy of T staging and differentiation degree of rectal cancer,providing a new approach to improve the preoperative assessment system of rectal cancer.This combined diagnostic model has important clinical application value,but further validation is needed through large-scale multicenter studies. 展开更多
关键词 Rectal cancer dynamic contrast-enhanced magnetic resonance imaging Serum tumor markers T staging Differentiation degree Diagnostic value
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Diagnostic dynamic contrast-enhanced magnetic resonance imaging blood-brain barrier assessment combined with plasma biomarkers for mild cog itive impairment
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作者 Ling Sun Meng-Rong Xu +5 位作者 Cheng-Yu Zhou Shao-Dong Cao Xiao-Liang Zhang Si-Qi Guan Wen-Xu Sang Xu-Ling Li 《World Journal of Psychiatry》 2025年第6期166-176,共11页
BACKGROUND The role of cerebral microvascular dysfunction in early cognitive impairment and dementia has become increasingly recognized.Furthermore,pathological changes in both Alzheimer’s disease and vascular dement... BACKGROUND The role of cerebral microvascular dysfunction in early cognitive impairment and dementia has become increasingly recognized.Furthermore,pathological changes in both Alzheimer’s disease and vascular dementia are almost always associated with cerebral hemodynamic deficits.AIM To investigate the diagnostic performance of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)assessment of the blood-brain barrier(BBB)in combination with relevant plasma biomarkers for mild cognitive impairment(MCI).METHODS This study selected 50 patients with non-amnestic MCI(na-MCI group),52 patients with amnestic MCI(a-MCI group),and 55 healthy elderly controls(control group).The Chinese version of the Montreal cognitive assessment(MoCA),auditory verbal learning test(AVLT),Hamilton anxiety/depression scale(HAMA/HAMD),and activity of daily living(ADL)scales were used to analyze the characteristics of mental and behavioral symptoms of patients with MCI.The DCE-MRI technique was used to assess the contrast enhancement kinetics.The Patlak model was utilized to analyze the BBB permeability(volume transfer constants).Further,fasting blood was was used to quantify plasma homocysteine(Hcy),β-amyloid protein(Aβ)40,Aβ42,human phosphorylated tau-181 protein(p-tau181),intercellular adhesion molecule-1(ICAM-1),vascular cell adhesion molecule-1(VCAM-1),and plasminogen activator inhibitor-1(PAI-1)levels,as well as serum neurofilament light chain(NFL)and glial fibrillary acidic protein(GFAP)concentrations.RESULTS The na-MCI and a-MCI groups demonstrated significantly lower MoCA and AVLT-Huashan version scores,and statistically higher HAMA,HAMD,and ADL scores compared to the control group.Moreover,the a-MCI group showed notably higher HAMA,HAMD,and ADL scores compared to the na-MCI group.Cranial MRI results revealed significant disparities in cerebral blood flow in the left and right frontal lobes,temporal lobes,hippocampi,cuneus,precuneus,parietal lobes,basal ganglia,and occipital lobes between the a-MCI and na-MCI groups.Compared to healthy controls,patients with MCI demonstrated a smaller amplitude of hippocampal contrast enhancement kinetics and a slower decay rate,indicating smaller vascular volume and increased BBB permeability.Further,Hcy,p-tau181,ICAM-1,VCAM-1,PAI-1,and NFL levels were substantially higher in the a-MCI group than in the na-MCI group,whereas the Aβ42 level was significantly lower.We did not observe any significant differences in Aβ40 and GFAP levels.CONCLUSION Patients with MCI may have experienced cerebrovascular system changes in the hippocampal region.Disorders associated with changes in cerebral blood supply may begin before pathophysiological changes are visible by imaging,which provides references for the assessment and treatment of patients with cognitive disorders.Further,DCE-MRI provides a noninvasive approach to diagnose subtle BBB leakage associated with cerebrovascular pathology. 展开更多
关键词 dynamic contrast-enhanced magnetic resonance imaging Blood-brain barrier Mild cognitive impairment Auditory verbal learning test Montreal cognitive assessment
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An approach on dynamic earthquake prediction by georesistivitymeasurements
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作者 张洪魁 沈启兴 +2 位作者 吴卫 赵玉林 毛桐恩 《Acta Seismologica Sinica(English Edition)》 CSCD 1996年第3期79-86,共8页
Experiences on earthquake prediction accumulated by the Chinese scientists in the last 20 years were synthetically analyzed. A prediction program was set up to demonstrate the development of the georesistivity anoma... Experiences on earthquake prediction accumulated by the Chinese scientists in the last 20 years were synthetically analyzed. A prediction program was set up to demonstrate the development of the georesistivity anomaly by using of the dynamic image, accordingly the earthquake prone area can be recognized. By revising the DYBS Ⅰ, which was developed in 1989, and adding some latest achievements, we worked out a software on earthquake prediction by the geoelectric method the DYBS Ⅱ. Some new feature of DYBS Ⅱ are: the anomalous area may be determined by the space distribution and its time variation of geoelectric parameters; The dynamic process that is associated with the development of earthquake anomaly can be displayed on the computer screen; Technique for the prediction of an impending earthquake was included too. Some results of the Tangshan earthquake were presented at the end of this paper. 展开更多
关键词 earthquake prediction georesistivity precursor identification model dynamic image parameter.
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Pancreatic carcinoma coexisting with chronic pancreatitis versus tumor-forming pancreatitis:Diagnostic utility of the time-signal intensity curve from dynamic contrast-enhanced MR imaging 被引量:30
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作者 Yoshitsugu Tajima Tamotsu Kuroki +3 位作者 Ryuji Tsutsumi Ichiro Isomoto Masataka Uetani Takashi Kanematsu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第6期858-865,共8页
AIM: To evaluate the ability of the time-signal intensity curve (TIC) of the pancreas obtained from dynamic contrast-enhanced magnetic resonance imaging (MRI) for differentiation of focal pancreatic masses, especially... AIM: To evaluate the ability of the time-signal intensity curve (TIC) of the pancreas obtained from dynamic contrast-enhanced magnetic resonance imaging (MRI) for differentiation of focal pancreatic masses, especially pancreatic carcinoma coexisting with chronic pancreatitis and tumor-forming pancreatitis. METHODS: Forty-eight consecutive patients who underwent surgery for a focal pancreatic mass, including pancreatic ductal carcinoma (n = 33), tumor-forming pancreatitis (n = 8), and islet cell tumor (n = 7), were reviewed. Five pancreatic carcinomas coexisted with longstanding chronic pancreatitis. The pancreatic TICs were obtained from the pancreatic mass and the pancreatic parenchyma both proximal and distal to the mass lesion in each patient, prior to surgery, and were classified into 4 types according to the time to a peak: 25 s and 1, 2, and 3 min after the bolus injection of contrast material, namely, type-Ⅰ, Ⅱ, Ⅲ, and Ⅳ, respectively, and were then compared to the corresponding histological pancreatic conditions. RESULTS: Pancreatic carcinomas demonstrated type-Ⅲ (n = 13) or Ⅳ (n = 20) TIC. Tumor-forming pancreatitis showed type-Ⅱ (n = 5) or Ⅲ (n = 3) TIC. All islet cell tumors revealed type-Ⅰ. The type-Ⅳ TIC was only recognized in pancreatic carcinoma, and the TIC of carcinoma always depicted the slowest rise to a peak among the 3 pancreatic TICs measured in each patient, even in patients with chronic pancreatitis.CONCLUSION: Pancreatic TIC from dynamic MRI provides reliable information for distinguishing pancreatic carcinoma from other pancreatic masses, and may enable us to avoid unnecessary pancreatic surgery and delays in making a correct diagnosis of pancreatic carcinoma, especially, in patients with longstanding chronic pancreatitis. 展开更多
关键词 Pancreatic carcinoma Chronic pancreatitis Focal pancreatic mass Tumor-forming pancreatitis Differential diagnosis dynamic magnetic resonance imaging Time-signal intensity curve
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Dynamic imaging of metallic contamination plume based on self-potential data 被引量:5
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作者 Yi-an CUI Xiao-xiong ZHU +2 位作者 Wen-sheng WEI Jian-xin LIU Tie-gang TONG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第8期1822-1830,共9页
A dynamic imaging method for monitoring self-potential data was proposed.Based on the Darcy’s law and Archie’sformulas,a dynamic model was built as a state model to simulate the transportation of metallic ions in po... A dynamic imaging method for monitoring self-potential data was proposed.Based on the Darcy’s law and Archie’sformulas,a dynamic model was built as a state model to simulate the transportation of metallic ions in porous medium,and theNernst equation was used to calculate the redox potential of metallic ions for observation modeling.Then,the state model andobservation model form an extended Kalman filter cycle to perform dynamic imaging.The noise added synthetic data imaging testshows that the extended Kalman filter can effectively fuse the model evolution and observed self-potential data.The further sandboxmonitoring experiment also demonstrates that the self-potential can be used to monitor the activities of metallic ions and exactlyretrieve the dynamic process of metallic contamination. 展开更多
关键词 dynamic imaging SELF-POTENTIAL metallic contamination extended Kalman filter
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DCE-MRI in hepatocellular carcinoma-clinical and therapeutic image biomarker 被引量:16
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作者 Bang-Bin Chen Tiffany Ting-Fang Shih 《World Journal of Gastroenterology》 SCIE CAS 2014年第12期3125-3134,共10页
Dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)enables tumor vascular physiology to be assessed.Within the tumor tissue,contrast agents(gadolinium chelates)extravasate from intravascular into the extrava... Dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)enables tumor vascular physiology to be assessed.Within the tumor tissue,contrast agents(gadolinium chelates)extravasate from intravascular into the extravascular extracellular space(EES),which results in a signal increase on T1-weighted MRI.The rate of contrast agents extravasation to EES in the tumor tissue is determined by vessel leakiness and blood flow.Thus,the signal measured on DCE-MRI represents a combination of permeability and perfusion.The semi-quantitative analysis is based on the calculation of heuristic parameters that can be extracted from signal intensity-time curves.These enhancing curves can also be deconvoluted by mathematical modeling to extract quantitative parameters that may reflect tumor perfusion,vascular volume,vessel permeability and angiogenesis.Because hepatocellular carcinoma(HCC)is a hypervascular tumor,many emerging therapies focused on the inhibition of angiogenesis.DCE-MRI combined with a pharmacokinetic model allows us to produce highly reproducible and reliable parametric maps of quantitative parameters in HCC.Successful therapies change quantitative parameters of DCE-MRI,which may be used as early indicators of tumor response to anti-angiogenesis agents that modulate tumor vasculature.In the setting of clinical trials,DCE-MRI may provide relevant clinical information on the pharmacodynamic and biologic effects of novel drugs,monitor treatment response and predict survival outcome in HCC patients. 展开更多
关键词 dynamic contrast-enhanced magnetic resonance imaging Perfusion magnetic resonance imaging Hepatocellular carcinoma Angiogenesis inhibitors Clinical trials
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