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Leading the Way to Lead──Focalizing the First Knitting Fair
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作者 Wang Ting 《China Textile》 2007年第9期38-40,共3页
This August, the city of Shanghai is so hot not only because of its high temperature, but also two textile industrial exhibitions held in Shanghai New International Expo Center attracted anumerous visitors and exhibit... This August, the city of Shanghai is so hot not only because of its high temperature, but also two textile industrial exhibitions held in Shanghai New International Expo Center attracted anumerous visitors and exhibitors to come to the modern city. 展开更多
关键词 Leading the Way to Lead focalizing the First Knitting Fair
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基于自适应空间特征增强的多视图深度估计
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作者 魏东 刘欢 +3 位作者 张潇瀚 李昌恺 孙天翼 张子优 《系统仿真学报》 CAS CSCD 北大核心 2024年第1期110-119,共10页
为了提高多视图深度估计结果精度,提出一种基于自适应空间特征增强的多视图深度估计算法。设计了由改进后的特征金字塔网络(feature pyramid network,FPN)和自适应空间特征增强(adaptive space feature enhancement,ASFE)组成的多尺度... 为了提高多视图深度估计结果精度,提出一种基于自适应空间特征增强的多视图深度估计算法。设计了由改进后的特征金字塔网络(feature pyramid network,FPN)和自适应空间特征增强(adaptive space feature enhancement,ASFE)组成的多尺度特征提取模块,获取到具有全局上下文信息和位置信息的多尺度特征图像。通过残差学习网络对深度图进行优化,防止多次卷积操作出现重建边缘模糊的问题。通过分类的思想构建focal loss函数增强网络模型的判断能力。由实验结果可知,该算法在DTU(technical university of denmark)数据集上和CasMVSNet(Cascade MVSNet)算法相比,在整体精度误差、运行时间、显存资源占用上分别降低了14.08%、72.15%、4.62%。在Tanks and Temples数据集整体评价指标Mean上该模型优于其他算法,证明提出的基于自适应空间特征增强的多视图深度估计算法的有效性。 展开更多
关键词 多视图深度估计 自适应空间特征增强 残差学习网络 卷积操作 focal loss函数
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基于聚焦滤波的林业专题地图制图综合方法
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作者 陈春祥 《林业调查规划》 2024年第1期1-7,共7页
森林资源规划设计调查成果总是以连续的面状图斑呈现。当大比例尺二类调查成果图缩编为更小比例尺地图时,常常需要制图综合。如何在制图综合时既要简化多边形边界,又要保持各类型林相面积和位置的相对不变,是林业专题制图的一个难题。... 森林资源规划设计调查成果总是以连续的面状图斑呈现。当大比例尺二类调查成果图缩编为更小比例尺地图时,常常需要制图综合。如何在制图综合时既要简化多边形边界,又要保持各类型林相面积和位置的相对不变,是林业专题制图的一个难题。经大量实验发现,将实施制图综合的连续面状图斑要素从矢量格式转换为栅格格式,经Focal滤波器以Majority方式滤波处理后,再将滤波后结果从栅格数据转换为矢量数据,可较好地实现森林资源专题连续面状要素信息的制图综合。以云南省某地一个1万hm^(2)的实验区为例,使用该方法将1∶2.5万的森林资源二类调查成果图缩编为1∶25万。结果表明,缩编后,多边形边界简化,目视效果较好,各类型林相面积变化绝对值平均为0.2%,位置精确度平均值为94.68%。此方法已应用于云南森林资源状况图集相关专题图等的生产实践。 展开更多
关键词 林业专题地图 制图综合 连续面状图斑 地图缩编 Focal滤波器 位置精确度
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基于Res2Net的人脸表情识别方法
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作者 唐宏伟 丁祥 +3 位作者 邓嘉鑫 高方坤 罗佳强 王军权 《邵阳学院学报(自然科学版)》 2024年第2期28-35,共8页
为解决自然条件下人脸表情识别易受角度、光线、遮挡物的影响以及人脸表情数据集各类表情数量不均衡等问题,提出基于Res2Net的人脸表情识别方法。使用Res2Net50作为特征提取的主干网络,在预处理阶段对图像随机翻转、缩放、裁剪进行数据... 为解决自然条件下人脸表情识别易受角度、光线、遮挡物的影响以及人脸表情数据集各类表情数量不均衡等问题,提出基于Res2Net的人脸表情识别方法。使用Res2Net50作为特征提取的主干网络,在预处理阶段对图像随机翻转、缩放、裁剪进行数据增强,提升模型的泛化性。引入广义平均池化(generalized mean pooling, GeM)方式,关注图像中比较显著的区域,增强模型的鲁棒性;选用Focal Loss损失函数,针对表情类别不平衡和错误分类问题,提高较难识别表情的识别率。该方法在FER2013数据集上准确率达到了70.41%,相较于原Res2Net50网络提高了1.53%。结果表明,在自然条件下对人脸表情识别具有更好的准确性。 展开更多
关键词 表情识别 Focal Loss函数 广义平均池化模块 Res2Net50
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基于Unet+Attention的胸部CT影像支气管分割算法
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作者 张子明 周庆华 +1 位作者 薛洪省 覃文军 《中国生物医学工程学报》 CAS CSCD 北大核心 2024年第1期60-69,共10页
目前肺气管分割中,由于CT图像灰度分布复杂,分割目标像素近似,易造成过分割;而且肺气管像素较少,难以得到更多目标特征,造成细小肺气管容易被忽略。针对这些难点,本研究提出结合Unet网络和注意力机制的肺气管分割算法,注意力机制使用的... 目前肺气管分割中,由于CT图像灰度分布复杂,分割目标像素近似,易造成过分割;而且肺气管像素较少,难以得到更多目标特征,造成细小肺气管容易被忽略。针对这些难点,本研究提出结合Unet网络和注意力机制的肺气管分割算法,注意力机制使用的是关注通道域和空间域的卷积块注意力模型(CBAM),该模型提高了气管特征权重。在损失函数方面,针对原始数据中正负样本失衡的问题,引入focal loss损失函数,该函数对标准交叉熵损失函数进行了改进,使难分类样本在训练过程中得到更多关注;最后通过八连通域判断将孤立点去除,保留较大的几个连通域,即最后的肺气管部分。选用由合作医院提供的24组CT影像和43组CTA影像,共计26157张切片图像作为数据集,进行分割实验。结果表明,分割准确率能够达到0.86,过分割率和欠分割率均值为0.28和0.39。经过注意力模块和损失函数的消融实验,在改进前的准确率、过分割率和欠分割率分别为0.81、0.30、0.40,可见其分割效果均不如Unet+Attention方法。与其他常用方法在相同条件下进行比较后,在保证过分割率和欠分割率不变的情况下,所提出的算法得到了最高的准确率,较好地解决了细小气管分割不准确的问题。 展开更多
关键词 医学图像分割 肺气管 Unet 注意力机制 focal loss
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基于改进轻量化YOLOX的无人机航拍目标检测算法
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作者 胡潇 潘申富 《计算机测量与控制》 2024年第1期57-63,共7页
针对小型无人机在巡逻航拍中的应用,提出了一种改进的轻量化目标检测算法,有效解决巡逻过程中空地无线传输信道和机载端计算能力双重受限的难题;该算法在YOLOX算法的基础上,首先利用Mobilenetv2代替CSPDarknet骨干网络作为特征提取网络... 针对小型无人机在巡逻航拍中的应用,提出了一种改进的轻量化目标检测算法,有效解决巡逻过程中空地无线传输信道和机载端计算能力双重受限的难题;该算法在YOLOX算法的基础上,首先利用Mobilenetv2代替CSPDarknet骨干网络作为特征提取网络,降低了模型参数量和计算量,提高目标检测实时性;其次为了弥补轻量化带来的检测精度下降,考虑检测目标框的长宽比引入CIOU定位损失函数,提升目标定位的精度;同时为了平衡训练过程中的正负难易样本,引入Focal Loss置信度损失函数提升模型的检测性能;基于VisDrone2019-DET数据集实验表明,改进后算法模型参数量降低了56.2%,计算量降低了52.5%,在检测精度没有明显下降情况下单张图片推理时间减少了41.4%;最后,将改进后的算法部署到Nvidia Jetson Xavier NX机载端,测得模型检测帧率可达22 FPS,改进后算法满足巡逻任务的应用需求。 展开更多
关键词 无人机 目标检测 轻量化 YOLOX Focal Loss CIOU
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Design and fabrication of compound varifocal lens driven by polydimethylsiloxane film elastic deformation
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作者 缪文浩 韩泽峰 +3 位作者 赵瑞 梁忠诚 寇松峰 徐荣青 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期342-346,共5页
A compound varifocal lens based on electromagnetic drive technology is designed and fabricated, where the polydimethylsiloxane(PDMS) film acts as a driving component, while the PDMS biconvex lens and the plane-concave... A compound varifocal lens based on electromagnetic drive technology is designed and fabricated, where the polydimethylsiloxane(PDMS) film acts as a driving component, while the PDMS biconvex lens and the plane-concave lens form a coaxial compound lens system. The plane-concave lens equipped with driving coils is installed directly above the PDMS lens surrounded by the annular magnet. When different currents are applied, the annular magnet moves up and down, driving the PDMS film to undergo elastic deformation, and then resulting in longitudinal movement of the PDMS lens. The position change of the PDMS lens changes the focal length of the compound lens system. To verify the feasibility and practicability of this design, a prototype of our compound lens system is fabricated in experiment. Our proposed compound lens shows that its zoom ability reaches 9.28 mm when the current ranges from -0.20 A to 0.21 A. 展开更多
关键词 compound varifocal lens PDMS film elastic deformation focal length electromagnetic force zoom ability
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Constraint on the focal mechanism of the 2011 Tohoku earthquake from the radial modes
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作者 Weikun Chen Hao Ding 《Geodesy and Geodynamics》 EI CSCD 2024年第1期27-32,共6页
Different from other normal modes of the Earth’s free oscillation that depend on all the six components(M_(rr),M_(tt),M_(pp),M_(rt),M_(rp),and M_(tp))of the centroid moment tensor,the amplitudes of the radial modes d... Different from other normal modes of the Earth’s free oscillation that depend on all the six components(M_(rr),M_(tt),M_(pp),M_(rt),M_(rp),and M_(tp))of the centroid moment tensor,the amplitudes of the radial modes depend on the M_(rr)component(e.g.,scalar moment(M_(0)),dip(δ),and slip(λ))and hypocenter depth of the focal mechanism,and hence can be easily used to constrain these parameters of the focal mechanism.In this study,we use the superconducting gravimeter(SG)records after the 2011 Tohoku earthquake to analyze the radial modes_(0)S_(0)and_(1)S_(0).Based on the solutions of the focal mechanism provided by the GCMT and USGS,we can obtain the theoretical amplitudes of these two radial modes.Comparing the theoretical amplitudes with the observation amplitudes,it is found that there are obvious differences between the former and the latter,which means that the GCMT and USGS focal mechanisms cannot well represent the real focal mechanism of the 2011 event.Taking the GCMT solution as a reference and changing the depth and the three parameters of the M_(rr)moment,the scalar moment(M_(0))and the dip(δ)have significant influences,but the effects of the slip(λ)and the depth are minor.After comparisons,we provide a new constraint(M_(0)=5.8±0.09×10^(22)N·m,δ=10.1±0.08°,λ=88°,and depth=20 km)for the focal mechanism of the 2011 event.In addition,we further determine the center frequency(1.631567±2.6e^(-6)mHz)and quality factor(2046.4±50.1)of the_(1)S_(0)mode. 展开更多
关键词 Focal mechanism Radial modes Gravity observation
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ProNet Adaptive Retinal Vessel Segmentation Algorithm Based on Improved UperNet Network
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作者 Sijia Zhu Pinxiu Wang Ke Shen 《Computers, Materials & Continua》 SCIE EI 2024年第1期283-302,共20页
This paper proposes a new network structure,namely the ProNet network.Retinal medical image segmentation can help clinical diagnosis of related eye diseases and is essential for subsequent rational treatment.The basel... This paper proposes a new network structure,namely the ProNet network.Retinal medical image segmentation can help clinical diagnosis of related eye diseases and is essential for subsequent rational treatment.The baseline model of the ProNet network is UperNet(Unified perceptual parsing Network),and the backbone network is ConvNext(Convolutional Network).A network structure based on depth-separable convolution and 1×1 convolution is used,which has good performance and robustness.We further optimise ProNet mainly in two aspects.One is data enhancement using increased noise and slight angle rotation,which can significantly increase the diversity of data and help the model better learn the patterns and features of the data and improve the model’s performance.Meanwhile,it can effectively expand the training data set,reduce the influence of noise and abnormal data in the data set on the model,and improve the accuracy and reliability of the model.Another is the loss function aspect,and we finally use the focal loss function.The focal loss function is well suited for complex tasks such as object detection.The function will penalise the loss carried by samples that the model misclassifies,thus enabling better training of the model to avoid these errors while solving the category imbalance problem as a way to improve image segmentation density and segmentation accuracy.From the experimental results,the evaluation metrics mIoU(mean Intersection over Union)enhanced by 4.47%,and mDice enhanced by 2.92% compared to the baseline network.Better generalization effects and more accurate image segmentation are achieved. 展开更多
关键词 Retinal segmentation multifaceted optimization cross-fusion data enhancement focal loss
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Rapid report of source parameters of 2023 M6.2 Jishishan,Gansu earthquake sequence
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作者 ZhiGao Yang Jie Liu +2 位作者 YingYing Zhang Wen Yang XueMei Zhang 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期436-443,共8页
The M6.2 earthquake in Jishishan,Gansu Province,on December 18,2023,caused extraordinary earthquake disasters.It was located in the northern part of the north−south seismic zone,which is a key area for earthquake moni... The M6.2 earthquake in Jishishan,Gansu Province,on December 18,2023,caused extraordinary earthquake disasters.It was located in the northern part of the north−south seismic zone,which is a key area for earthquake monitoring in China.The newly built dense strong motion stations in this area provide unprecedented conditions for high-precision earthquake relocation,especially the earthquake focal depth.This paper uses the newly built strong motion and traditional broadband seismic networks to relocate the source locations of the M3.0 and above aftershocks and to invert their focal mechanisms.The horizontal error of earthquake location is estimated to be 0.5−1 km,and the vertical error is 1−2 km.The focal depth range of aftershocks is 9.6−14.6 km,distributed in a 12-km-long strip with SSE direction.Aftershocks in the south are more concentrated horizontally and vertically,while aftershocks in the north are more scattered.The focal mechanisms of the main shock and aftershocks are relatively consistent,and the P-axis orientation is consistent with the regional strain direction.There is a seismic blank area of M3.0 and above,about 3−5 km between the main shock and aftershocks.It is suggested that the energy released by the main shock rupture is concentrated in this area.Based on the earthquake location and focal mechanism of the main shock,it is inferred that the Northern Lajishan fault zone is the seismogenic structure of the main shock,and the main shock did not occur on the main fault,but on a secondary fault.The initial rupture depth and centroid depth of the main shock were 12.8 and 14.0 km,respectively.The source rupture depth may not be the main reason for the severe earthquake disaster. 展开更多
关键词 Jishishan earthquake earthquake relocation focal mechanism strong motion data
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基于改进YOLOX-s的车辆检测方法研究
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作者 张稀柳 张晓玲 何敏军 《系统仿真学报》 CAS CSCD 北大核心 2024年第2期487-496,共10页
为缓解车辆小目标漏检及误检问题,提出一种基于YOLOX网络的多尺度特征融合的改进车辆检测模型。设计基于深度可分离卷积的Ghost-CSP(cross stage partial),替换网络的部分跨阶段局部结构,加快检测速度;将模型的最大池化方式改进为Softp... 为缓解车辆小目标漏检及误检问题,提出一种基于YOLOX网络的多尺度特征融合的改进车辆检测模型。设计基于深度可分离卷积的Ghost-CSP(cross stage partial),替换网络的部分跨阶段局部结构,加快检测速度;将模型的最大池化方式改进为Softpool方式,并引入坐标注意力机制,增强待检测目标的特征表达,优化目标漏检问题;选用Focal Loss作为模型置信度损失函数以增加分类不准确样本的权重,提高模型对小目标的预测能力。实验结果表明:改进算法平均准确率提高到74.96%,速度达到73帧/s,在满足实时性要求下可以更好地完成车辆目标检测要求。 展开更多
关键词 YOLOX 多尺度特征融合 车辆检测模型 Softpool 坐标注意力 Focal Loss
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IR-YOLO: Real-Time Infrared Vehicle and Pedestrian Detection
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作者 Xiao Luo Hao Zhu Zhenli Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第2期2667-2687,共21页
Road traffic safety can decrease when drivers drive in a low-visibility environment.The application of visual perception technology to detect vehicles and pedestrians in infrared images proves to be an effective means... Road traffic safety can decrease when drivers drive in a low-visibility environment.The application of visual perception technology to detect vehicles and pedestrians in infrared images proves to be an effective means of reducing the risk of accidents.To tackle the challenges posed by the low recognition accuracy and the substan-tial computational burden associated with current infrared pedestrian-vehicle detection methods,an infrared pedestrian-vehicle detection method A proposal is presented,based on an enhanced version of You Only Look Once version 5(YOLOv5).First,A head specifically designed for detecting small targets has been integrated into the model to make full use of shallow feature information to enhance the accuracy in detecting small targets.Second,the Focal Generalized Intersection over Union(GIoU)is employed as an alternative to the original loss function to address issues related to target overlap and category imbalance.Third,the distribution shift convolution optimization feature extraction operator is used to alleviate the computational burden of the model without significantly compromising detection accuracy.The test results of the improved algorithm show that its average accuracy(mAP)reaches 90.1%.Specifically,the Giga Floating Point Operations Per second(GFLOPs)of the improved algorithm is only 9.1.In contrast,the improved algorithms outperformed the other algorithms on similar GFLOPs,such as YOLOv6n(11.9),YOLOv8n(8.7),YOLOv7t(13.2)and YOLOv5s(16.0).The mAPs that are 4.4%,3%,3.5%,and 1.7%greater than those of these algorithms show that the improved algorithm achieves higher accuracy in target detection tasks under similar computational resource overhead.On the other hand,compared with other algorithms such as YOLOv8l(91.1%),YOLOv6l(89.5%),YOLOv7(90.8%),and YOLOv3(90.1%),the improved algorithm needs only 5.5%,2.3%,8.6%,and 2.3%,respectively,of the GFLOPs.The improved algorithm has shown significant advancements in balancing accuracy and computational efficiency,making it promising for practical use in resource-limited scenarios. 展开更多
关键词 Traffic safety infrared image pedestrians and vehicles focal GIoU distributed shift convolution
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Diagnostic and therapeutic role of endoscopic ultrasound in liver diseases:A systematic review and meta-analysis
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作者 Eyad Gadour Abeer Awad +3 位作者 Zeinab Hassan Khalid Jebril Shrwani Bogdan Miutescu Hussein Hassan Okasha 《World Journal of Gastroenterology》 SCIE CAS 2024年第7期742-758,共17页
BACKGROUND In hepatology,the clinical use of endoscopic ultrasound(EUS)has experienced a notable increase in recent times.These applications range from the diagnosis to the treatment of various liver diseases.Therefor... BACKGROUND In hepatology,the clinical use of endoscopic ultrasound(EUS)has experienced a notable increase in recent times.These applications range from the diagnosis to the treatment of various liver diseases.Therefore,this systematic review summarizes the evidence for the diagnostic and therapeutic roles of EUS in liver diseases.AIM To examine and summarize the current available evidence of the possible roles of the EUS in making a suitable diagnosis in liver diseases as well as the therapeutic accuracy and efficacy.METHODS PubMed,Medline,Cochrane Library,Web of Science,and Google Scholar databases were extensively searched until October 2023.The methodological quality of the eligible articles was assessed using the Newcastle-Ottawa scale or Cochrane Risk of Bias tool.In addition,statistical analyses were performed using the Comprehensive Meta-Analysis software.RESULTS Overall,45 articles on EUS were included(28 on diagnostic role and 17 on therapeutic role).Pooled analysis demonstrated that EUS diagnostic tests had an accuracy of 92.4%for focal liver lesions(FLL)and 96.6%for parenchymal liver diseases.EUS-guided liver biopsies with either fine needle aspiration or fine needle biopsy had low complication rates when sampling FLL and parenchymal liver diseases(3.1%and 8.7%,respectively).Analysis of data from four studies showed that EUS-guided liver abscess had high clinical(90.7%)and technical success(90.7%)without significant complications.Similarly,EUS-guided interventions for the treatment of gastric varices(GV)have high technical success(98%)and GV obliteration rate(84%)with few complications(15%)and rebleeding events(17%).CONCLUSION EUS in liver diseases is a promising technique with the potential to be considered a first-line therapeutic and diagnostic option in selected cases. 展开更多
关键词 Focal liver lesion Liver abscess drainage Fine needle aspiration Gastric varices Endoscopic ultrasound
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Focal incidental colorectal fluorodeoxyglucose uptake:Should it be spotlighted?
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作者 Haejun Lee Kyung-Hoon Hwang 《World Journal of Clinical Cases》 SCIE 2024年第15期2466-2474,共9页
Fluorine-18 fluorodeoxyglucose(F-18 FDG)positron emission tomography/computed tomography(PET/CT)has emerged as a cornerstone in cancer evaluation imaging,with a well-established history spanning several years.This ima... Fluorine-18 fluorodeoxyglucose(F-18 FDG)positron emission tomography/computed tomography(PET/CT)has emerged as a cornerstone in cancer evaluation imaging,with a well-established history spanning several years.This imaging modality,encompassing the examination of the body from the base of the skull to the upper thighs,comprehensively covers the chest and abdominopelvic regions in a singular scan,allowing for a holistic assessment of nearly the entire body,including areas of marginal interest.The inherent advantage of this expansive scan range lies in its potential to unveil unexpected incidental abnormal hypermetabolic areas.The identification of incidental focal FDG uptake within colorectal regions during PET/CT scans is not an uncommon occurrence,albeit fraught with challenges associated with non-specific FDG uptake.The presence of benign colorectal lesions or physiological uptake poses a particular obstacle,as these may manifest with FDG uptake levels that mimic malignancy.Consequently,physicians are confronted with a diagnostic dilemma when encountering abnormal FDG uptake in unexpected colorectal areas.Existing studies have presented divergent results concerning these uptakes.Standardized uptake value and its derivatives have served as pivotal metrics in quantifying FDG uptake in PET images.In this article,we aim to succinctly explore the distinctive characteristics of FDG,delve into imaging findings,and elucidate the clinical significance of incidental focal colorectal uptake.This discussion aims to contribute valuable insights into the nuanced interpretation of such findings,fostering a comprehensive understanding. 展开更多
关键词 FOCAL INCIDENTAL COLORECTAL FLUORODEOXYGLUCOSE Positron emission tomography HYPERMETABOLISM
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Is endoscopic ultrasound a promising technique in the diagnosis and treatment of liver diseases?
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作者 Enver Zerem Željko Puljiz +3 位作者 Boris Zdilar Suad Kunosic Admir Kurtcehajic Omar Zerem 《World Journal of Gastroenterology》 SCIE CAS 2024年第22期2920-2922,共3页
Percutaneous ultrasound has been a longstanding method in the diagnostics and interventional procedures of liver diseases.In some countries,its use is restricted to radiologists,limiting access for other clinicians,su... Percutaneous ultrasound has been a longstanding method in the diagnostics and interventional procedures of liver diseases.In some countries,its use is restricted to radiologists,limiting access for other clinicians,such as gastroenterologists.Endoscopic ultrasound,as a novel technique,plays a crucial role in diagnosis and treatment of digestive diseases.However,its use is sometimes recommended for conditions where no clear advantage over percutaneous ultrasound exists,leaving the impression that clinicians sometimes resort to an endoscopic approach due to the unavailability of percutaneous options. 展开更多
关键词 Endoscopic ultrasound Percutaneous ultrasound Liver biopsy Fine needle aspiration Focal liver lesion Liver abscess drainage
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Unexpected focal fluorodeoxyglucose uptake in main organs;pass through or pass by?
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作者 Haejun Lee Kyung-Hoon Hwang 《World Journal of Clinical Cases》 SCIE 2024年第11期1885-1899,共15页
Since the inception of fluorine-18 fluorodeoxyglucose(F-18 FDG),positron emission tomography/computed tomography(PET/CT)utilizing F-18 FDG has become widely accepted as a valuable imaging modality in the field of onco... Since the inception of fluorine-18 fluorodeoxyglucose(F-18 FDG),positron emission tomography/computed tomography(PET/CT)utilizing F-18 FDG has become widely accepted as a valuable imaging modality in the field of oncology,with global prevalence in clinical practice.Given that a single Torso PET/CT scan encompasses the anatomical region from the skull base to the upper thigh,the detection of incidental abnormal focal hypermetabolism in areas of limited clinical interest is both feasible and not uncommon.Numerous investigations have been undertaken to delineate the distinctive features of these findings,yet the outcomes have proven inconclusive.The incongruent results of these studies present a challenge for physicians,leaving them uncertain about the appropriate course of action.This article provides a succinct overview of the characteristics of fluorodeoxyglucose,followed by a comprehensive discussion of the imaging findings and clinical significance associated with incidental focal abnormal F-18 FDG activity in several representative organs.In conclusion,while the prevalence of unrecognized malignancy varies across organs,malignancies account for a substantial proportion,ranging from approximately one-third to over half,of incidental focal uptake.In light of these rates,physicians are urged to exercise vigilance in not disregarding unexpected uptake,facilitating more assured clinical decisions,and advocating for further active evaluation. 展开更多
关键词 INCIDENTAL FOCAL INCIDENTALOMA FLUORODEOXYGLUCOSE Positron emission tomography HYPERMETABOLISM
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基于改进YOLOv5的织物缺陷检测
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作者 陈淼 张胜利 季坚莞 《毛纺科技》 CAS 北大核心 2024年第1期99-106,共8页
鉴于织物表面纹理复杂导致织物缺陷检测准确率低以及小目标检测困难等问题,提出一种基于改进YOLOv5的织物缺陷检测算法。首先,在YOLOv5的骨干网络上,增加CBAM注意力机制,从而强化有用的特征信息弱化无用的特征信息;其次,将Neck层的路径... 鉴于织物表面纹理复杂导致织物缺陷检测准确率低以及小目标检测困难等问题,提出一种基于改进YOLOv5的织物缺陷检测算法。首先,在YOLOv5的骨干网络上,增加CBAM注意力机制,从而强化有用的特征信息弱化无用的特征信息;其次,将Neck层的路径聚合网络(PANet)用加权双向特征金字塔网络(Bi-FPN)替换,从而更好地平衡多尺度特征信息,提高小目标检测的特征能力。最后,通过改进损失函数,使用Focal EIOU Loss损失函数来代替CIOU Loss损失函数,不仅使得收敛速度更快,而且可以有效的解决难易样本不平衡问题。实践证明:改进后的训练模型平均精度均值mAP值为84.5%,比未改进增加了4.7%,可满足实际生产中的织物缺陷检测要求。 展开更多
关键词 YOLOv5 缺陷检测 注意力机制 加权双向特征金字塔 Focal EIOU Loss
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Carcinoembryonic antigen in the diagnosis,treatment,and follow-up of focal liver lesions
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作者 Osman Nuri Dilek Dilaraİrem Arslan Kahraman Gökhan Kahraman 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第4期999-1007,共9页
In this editorial review,we comment on the article published in the recent issue of the World Journal of Gastrointestinal Surgery.Carcinoembryonic antigen(CEA)is a fetal glycoprotein and can be secreted in very small ... In this editorial review,we comment on the article published in the recent issue of the World Journal of Gastrointestinal Surgery.Carcinoembryonic antigen(CEA)is a fetal glycoprotein and can be secreted in very small amounts from healthy adults after birth.CEA is widely used not only for diagnostic tumor markers but also importantly for the management of some gastrointestinal tumors.The most common clinical use is surveillance for the monitoring of colorectal carcinoma.However,CEA can become elevated in several malign or benign characterized pathologies.Serum CEA level may vary depending on the location of the lesion,whether it metastasizes or not,and its histopathological characteristics.It has been determined that cases with high preoperative CEA have a more aggressive course and the risk of metastasis to the lymph tissue and liver increases.In this editorial review,we focused on evaluating the role of CEA in clinical practice with a holistic approach,including the diagnostic and prognostic significance of CEA in patients with focal liver lesions,the role of CEA in follow-up after definitive surgery,and also hepatic resection for metastasis,and the management of all patients with raised CEA. 展开更多
关键词 Carcinoembriyonic antigen Liver Focal liver lesions METASTASIS SURGERY PROGNOSIS SURVEILLANCE
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Degradation of FAK-targeting by proteolytic targeting chimera technology to inhibit the metastasis of hepatocellular carcinoma
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作者 XINFENG ZHANG SHUANG LI +8 位作者 MEIRU SONG YUE CHEN LIANGZHENG CHANG ZHERUI LIU HONGYUAN DAI YUTAO WANG GANGQI YANG YUN JIANG YINYING LU 《Oncology Research》 SCIE 2024年第4期679-690,共12页
Liver cancer is a prevalent malignant cancer,ranking third in terms of mortality rate.Metastasis and recurrence primarily contribute to the high mortality rate of liver cancer.Hepatocellular carcinoma(HCC)has low expr... Liver cancer is a prevalent malignant cancer,ranking third in terms of mortality rate.Metastasis and recurrence primarily contribute to the high mortality rate of liver cancer.Hepatocellular carcinoma(HCC)has low expression of focal adhesion kinase(FAK),which increases the risk of metastasis and recurrence.Nevertheless,the efficacy of FAK phosphorylation inhibitors is currently limited.Thus,investigating the mechanisms by which FAK affects HCC metastasis to develop targeted therapies for FAK may present a novel strategy to inhibit HCC metastasis.This study examined the correlation between FAK expression and the prognosis of HCC.Additionally,we explored the impact of FAK degradation on HCC metastasis through wound healing experiments,transwell invasion experiments,and a xenograft tumor model.The expression of proteins related to epithelial-mesenchymal transition(EMT)was measured to elucidate the underlying mechanisms.The results showed that FAK PROTAC can degrade FAK,inhibit the migration and invasion of HCC cells in vitro,and notably decrease the lung metastasis of HCC in vivo.Increased expression of E-cadherin and decreased expression of vimentin indicated that EMT was inhibited.Consequently,degradation of FAK through FAK PROTAC effectively suppressed liver cancer metastasis,holding significant clinical implications for treating liver cancer and developing innovative anti-neoplastic drugs. 展开更多
关键词 Hepatocellular carcinoma(HCC) Focal adhesion kinase(FAK) Proteolytic targeting chimera technology(PROTAC) Epithelial-mesenchymal transformation(EMT) METASTASIS
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Clinicopathological features and medium-term outcomes of histologic variants of primary focal segmental glomerulosclerosis in adults:A retrospective study
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作者 Nazarul Hassan Jafry Shumaila Manan +1 位作者 Rahma Rashid Muhammed Mubarak 《World Journal of Nephrology》 2024年第1期14-24,共11页
BACKGROUND The Columbia classification identified five histological variants of focal segmental glomerulosclerosis(FSGS).The prognostic significance of these variants remains controversial.AIM To evaluate the relative... BACKGROUND The Columbia classification identified five histological variants of focal segmental glomerulosclerosis(FSGS).The prognostic significance of these variants remains controversial.AIM To evaluate the relative frequency,clinicopathologic characteristics,and medium-term outcomes of FSGS variants at a single center in Pakistan.METHODS This retrospective study was conducted at the Department of Nephrology,Sindh Institute of Urology and Transplantation,Karachi,Pakistan on all consecutive adults(≥16 years)with biopsy-proven primary FSGS from January 1995 to December 2017.Studied subjects were treated with steroids as a first-line therapy.The response rates,doubling of serum creatinine,and kidney failure(KF)with replacement therapy were compared between histological variants using ANOVA or Kruskal Wallis,and Chi-square tests as appropriate.Data were analyzed by SPSS version 22.0.P-value≤0.05 was considered significant.RESULTS A total of 401 patients were diagnosed with primary FSGS during the study period.Among these,352(87.7%)had a designated histological variant.The not otherwise specified(NOS)variant was the commonest,being found in 185(53.9%)patients,followed by the tip variant in 100(29.1%)patients.Collapsing(COL),cellular(CEL),and perihilar(PHI)variants were seen in 58(16.9%),6(1.5%),and 3(0.7%)patients,respectively.CEL and PHI variants were excluded from further analysis due to small patient numbers.The mean follow-up period was 36.5±29.2 months.Regarding response rates of variants,patients with TIP lesions achieved remission more frequently(59.5%)than patients with NOS(41.8%)and COL(24.52%)variants(P<0.001).The hazard ratio of complete response among patients with the COL variant was 0.163[95%confidence interval(CI):0.039-0.67]as compared to patients with NOS.The TIP variant showed a hazard ratio of 2.5(95%CI:1.61-3.89)for complete remission compared to the NOS variant.Overall,progressive KF was observed more frequently in patients with the COL variant,43.4%(P<0.001).Among these,24.53%of patients required kidney replacement therapy(P<0.001).The hazard ratio of doubling of serum creatinine among patients with the COL variant was 14.57(95%CI:1.87-113.49)as compared to patients with the TIP variant.CONCLUSION In conclusion,histological variants of FSGS are predictive of response to treatment with immunosuppressants and progressive KF in adults in our setup. 展开更多
关键词 ADULTS Columbia classification Focal segmental glomerulosclerosis Histological variants Kidney failure Kidney failure with replacement therapy
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