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Sign language data quality improvement based on dual information streams
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作者 CAI Jialiang YUAN Tiantian 《Optoelectronics Letters》 2025年第6期342-347,共6页
Sign language dataset is essential in sign language recognition and translation(SLRT). Current public sign language datasets are small and lack diversity, which does not meet the practical application requirements for... Sign language dataset is essential in sign language recognition and translation(SLRT). Current public sign language datasets are small and lack diversity, which does not meet the practical application requirements for SLRT. However, making a large-scale and diverse sign language dataset is difficult as sign language data on the Internet is scarce. In making a large-scale and diverse sign language dataset, some sign language data qualities are not up to standard. This paper proposes a two information streams transformer(TIST) model to judge whether the quality of sign language data is qualified. To verify that TIST effectively improves sign language recognition(SLR), we make two datasets, the screened dataset and the unscreened dataset. In this experiment, this paper uses visual alignment constraint(VAC) as the baseline model. The experimental results show that the screened dataset can achieve better word error rate(WER) than the unscreened dataset. 展开更多
关键词 sign language dataset data quality improvement two information streams t dual information streams sign language data sign language translation sign language recognition sign language datasets
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YOLO-SDW: Traffic Sign Detection Algorithm Based on YOLOv8s Skip Connection and Dynamic Convolution
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作者 Qing Guo Juwei Zhang Bingyi Ren 《Computers, Materials & Continua》 2026年第1期1433-1452,共20页
Traffic sign detection is an important part of autonomous driving,and its recognition accuracy and speed are directly related to road traffic safety.Although convolutional neural networks(CNNs)have made certain breakt... Traffic sign detection is an important part of autonomous driving,and its recognition accuracy and speed are directly related to road traffic safety.Although convolutional neural networks(CNNs)have made certain breakthroughs in this field,in the face of complex scenes,such as image blur and target occlusion,the traffic sign detection continues to exhibit limited accuracy,accompanied by false positives and missed detections.To address the above problems,a traffic sign detection algorithm,You Only Look Once-based Skip Dynamic Way(YOLO-SDW)based on You Only Look Once version 8 small(YOLOv8s),is proposed.Firstly,a Skip Connection Reconstruction(SCR)module is introduced to efficiently integrate fine-grained feature information and enhance the detection accuracy of the algorithm in complex scenes.Secondly,a C2f module based on Dynamic Snake Convolution(C2f-DySnake)is proposed to dynamically adjust the receptive field information,improve the algorithm’s feature extraction ability for blurred or occluded targets,and reduce the occurrence of false detections and missed detections.Finally,the Wise Powerful IoU v2(WPIoUv2)loss function is proposed to further improve the detection accuracy of the algorithm.Experimental results show that the average precision mAP@0.5 of YOLO-SDW on the TT100K dataset is 89.2%,and mAP@0.5:0.95 is 68.5%,which is 4%and 3.3%higher than the YOLOv8s baseline,respectively.YOLO-SDW ensures real-time performance while having higher accuracy. 展开更多
关键词 Traffic sign detection YOLOv8 object detection deep learning
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Evolutionary neural architecture search for traffic sign recognition
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作者 SONG Changwei MA Yongjie +1 位作者 PING Haoyu SUN Lisheng 《Optoelectronics Letters》 2025年第7期434-440,共7页
Convolutional neural networks(CNNs)exhibit superior performance in image feature extraction,making them extensively used in the area of traffic sign recognition.However,the design of existing traffic sign recognition ... Convolutional neural networks(CNNs)exhibit superior performance in image feature extraction,making them extensively used in the area of traffic sign recognition.However,the design of existing traffic sign recognition algorithms often relies on expert knowledge to enhance the image feature extraction networks,necessitating image preprocessing and model parameter tuning.This increases the complexity of the model design process.This study introduces an evolutionary neural architecture search(ENAS)algorithm for the automatic design of neural network models tailored for traffic sign recognition.By integrating the construction parameters of residual network(ResNet)into evolutionary algorithms(EAs),we automatically generate lightweight networks for traffic sign recognition,utilizing blocks as the fundamental building units.Experimental evaluations on the German traffic sign recognition benchmark(GTSRB)dataset reveal that the algorithm attains a recognition accuracy of 99.32%,with a mere 2.8×10^(6)parameters.Experimental results comparing the proposed method with other traffic sign recognition algorithms demonstrate that the method can more efficiently discover neural network architectures,significantly reducing the number of network parameters while maintaining recognition accuracy. 展开更多
关键词 traffic sign recognitionhoweverthe expert knowledge image feature extraction model parameter tuningthis evolutionary neural architecture search enas algorithm traffic sign recognition model design image preprocessing
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Visual feature inter-learning for sign language recognition in emergency medicine
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作者 WEI Chao LI Yunpeng LIU Jingze 《Optoelectronics Letters》 2025年第10期619-625,共7页
Accessible communication based on sign language recognition(SLR)is the key to emergency medical assistance for the hearing-impaired community.Balancing the capture of both local and global information in SLR for emerg... Accessible communication based on sign language recognition(SLR)is the key to emergency medical assistance for the hearing-impaired community.Balancing the capture of both local and global information in SLR for emergency medicine poses a significant challenge.To address this,we propose a novel approach based on the inter-learning of visual features between global and local information.Specifically,our method enhances the perception capabilities of the visual feature extractor by strategically leveraging the strengths of convolutional neural network(CNN),which are adept at capturing local features,and visual transformers which perform well at perceiving global features.Furthermore,to mitigate the issue of overfitting caused by the limited availability of sign language data for emergency medical applications,we introduce an enhanced short temporal module for data augmentation through additional subsequences.Experimental results on three publicly available sign language datasets demonstrate the efficacy of the proposed approach. 展开更多
关键词 sign language recognition slr visual feature inter learning emergency medicine visual feature extractor capture both local global information enhances perception capabilities emergency medical assistance sign language recognition
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Distance Compatibility for the Direct Product of Signed Graphs
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作者 Ziqiang FANG Qiannan NIU Haizhen REN 《Journal of Mathematical Research with Applications》 2025年第5期569-580,共12页
A graph whose edges are labeled either as positive or negative is called a signed graph.Hameed et al.introduced signed distance and distance compatibility in 2021,initially to characterize balanced signed graphs which... A graph whose edges are labeled either as positive or negative is called a signed graph.Hameed et al.introduced signed distance and distance compatibility in 2021,initially to characterize balanced signed graphs which have nice spectral properties.This article mainly studies the conjecture proposed by Shijin et al.on the distance compatibility of the direct product of signed graphs,and provides necessary and sufficient conditions for the distance compatibility of the direct product of signed graphs.Some further questions regarding distance compatibility are also posed. 展开更多
关键词 signed graph distance compatibility direct product of signed graphs
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Impact of emergency evacuation signage systems on passenger behavior during subway fires
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作者 BIAN Yang ZHAO Xuena +2 位作者 ZHAO Xiaohua ZHANG Yu LIU Zhuoran 《Journal of Southeast University(English Edition)》 2025年第3期325-337,共13页
To explore the influence of emergency evacuation signs on passenger behavior during subway fires and improve evacuation efficiency in emergencies,this paper proposes a dynamic emergency evacuation sign system.A simula... To explore the influence of emergency evacuation signs on passenger behavior during subway fires and improve evacuation efficiency in emergencies,this paper proposes a dynamic emergency evacuation sign system.A simulation platform integrating building information modeling(BIM)and virtual reality(VR)technologies was em-ployed to create subway fire evacuation scenarios using both the current and proposed dynamic emergency evacuation signage systems.Through simulation experiments,fine-grained microscopic data on passenger behavior was collected.Seven indicators were selected to assess evacuation efficiency and wayfinding difficulty.The analysis explored the influence of evacuation signs on passenger behavior in both overall and decision-making areas,thereby validating the effectiveness of the new emergency evacuation signage system.The results show that the dynamic evacuation signage system significantly improves overall passenger evacuation efficiency and reduces decision-making errors.It also improves wayfinding efficiency in critical decision areas by reducing the need for direction identification,minimizing stopping times,and lowering the frequency of decision errors.The method for evaluating the effects of emergency evacuation signs on passenger evacuation behavior proposed in this study provides a robust theoretical basis for the design and optimization of emergency-oriented signs. 展开更多
关键词 emergency evacuation signs subway fire inci-dents evacuation behavior building information modeling(BIM)and virtual reality(VR)simulation technology op-timal design
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C型凝集素受体DC-SIGN及其在流感病毒感染中的研究进展 被引量:1
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作者 屠叶清 郑蕊 +1 位作者 罗德炎 王慧 《中国免疫学杂志》 北大核心 2025年第2期456-460,共5页
C型凝集素受体DC-SIGN是一类主要在树突状细胞表面表达的跨膜蛋白,其碳水化合物识别域可与多种病原体结合。近年随着人们对病毒感染免疫研究的深入,DC-SIGN在其中扮演的多方面作用逐渐被挖掘。作为一种模式识别分子,DC-SIGN在固有免疫... C型凝集素受体DC-SIGN是一类主要在树突状细胞表面表达的跨膜蛋白,其碳水化合物识别域可与多种病原体结合。近年随着人们对病毒感染免疫研究的深入,DC-SIGN在其中扮演的多方面作用逐渐被挖掘。作为一种模式识别分子,DC-SIGN在固有免疫应答、适应性免疫应答中均发挥重要作用,并可介导病毒顺式和反式感染。本文从DC-SIGN的结构与功能、表达与配体入手,介绍其在不同物种中的同源物,最后综述其在流感病毒感染中的作用,以期为研究和治疗DC-SIGN相关病毒感染提供新思路。 展开更多
关键词 C型凝集素 DC-sign(CD209) 流感病毒感染
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YOLO-based lightweight traffic sign detection algorithm and mobile deployment 被引量:1
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作者 WU Yaqin ZHANG Tao +2 位作者 NIU Jianjun CHANG Yan LIU Ganjun 《Optoelectronics Letters》 2025年第4期249-256,共8页
This paper proposes a lightweight traffic sign detection system based on you only look once(YOLO).Firstly,the classification to fusion(C2f)structure is integrated into the backbone network,employing deformable convolu... This paper proposes a lightweight traffic sign detection system based on you only look once(YOLO).Firstly,the classification to fusion(C2f)structure is integrated into the backbone network,employing deformable convolution and bi-directional feature pyramid network(BiFPN)_Concat to improve the adaptability of the network.Secondly,the simple attention module(SimAm)is embedded to prioritize key features and reduce the complexity of the model after the C2f layer at the end of the backbone network.Next,the focal efficient intersection over union(EloU)is introduced to adjust the weights of challenging samples.Finally,we accomplish the design and deployment for the mobile app.The results demonstrate improvements,with the F1 score of 0.8987,mean average precision(mAP)@0.5 of 98.8%,mAP@0.5:0.95 of 75.6%,and the detection speed of 50 frames per second(FPS). 展开更多
关键词 c f layer simple attention module simam reduce complexity traffic sign detection prioritize key features backbone networkemploying classification backbone networknextthe
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Constructing Representative Collective Signature Protocols Using The GOST R34.10-1994 Standard
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作者 Tuan Nguyen Kim Duy Ho Ngoc Nikolay A.Moldovyan 《Computers, Materials & Continua》 SCIE EI 2023年第1期1475-1491,共17页
The representative collective digital signature,which was suggested by us,is built based on combining the advantages of group digital signature and collective digital signature.This collective digital signature schema... The representative collective digital signature,which was suggested by us,is built based on combining the advantages of group digital signature and collective digital signature.This collective digital signature schema helps to create a unique digital signature that deputizes a collective of people representing different groups of signers and may also include personal signers.The advantage of the proposed collective signature is that it can be built based on most of the well-known difficult problems such as the factor analysis,the discrete logarithm and finding modulo roots of large prime numbers and the current digital signature standards of the United States and Russian Federation.In this paper,we use the discrete logarithmic problem on prime finite fields,which has been implemented in the GOST R34.10-1994 digital signature standard,to build the proposed collective signature protocols.These protocols help to create collective signatures:Guaranteed internal integrity and fixed size,independent of the number of members involved in forming the signature.The signature built in this study,consisting of 3 components(U,R,S),stores the information of all relevant signers in the U components,thus tracking the signer and against the“disclaim of liability”of the signer later is possible.The idea of hiding the signer’s public key is also applied in the proposed protocols.This makes it easy for the signing group representative to specify which members are authorized to participate in the signature creation process. 展开更多
关键词 signing collective signing group discrete logarithm group signature collective signature GOST standards
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New Representative Collective Signatures Based on the Discrete Logarithm Problem
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作者 Tuan Nguyen Kim Duy Ho Ngoc Nikolay A.Moldovyan 《Computers, Materials & Continua》 SCIE EI 2022年第10期783-799,共17页
The representative collective digital signature scheme allows the creation of a unique collective signature on document M that represents an entire signing community consisting of many individual signers and many diff... The representative collective digital signature scheme allows the creation of a unique collective signature on document M that represents an entire signing community consisting of many individual signers and many different signing groups,each signing group is represented by a group leader.On document M,a collective signature can be created using the representative digital signature scheme that represents an entire community consisting of individual signers and signing groups,each of which is represented by a group leader.The characteristic of this type of letter is that it consists of three elements(U,E,S),one of which(U)is used to store the information of all the signers who participated in the formation of the collective signature on document M.While storing this information is necessary to identify the signer and resolve disputes later,it greatly increases the size of signatures.This is considered a limitation of the collective signature representing 3 elements.In this paper,we propose and build a new type of collective signature,a collective signature representing 2 elements(E,S).In this case,the signature has been reduced in size,but it contains all the information needed to identify the signer and resolve disputes if necessary.To construct the approved group signature scheme,which is the basic scheme for the proposed representative collective signature schemes,we use the discrete logarithm problem on the prime finite field.At the end of this paper,we present the security analysis of the AGDS scheme and a performance evaluation of the proposed collective signature schemes. 展开更多
关键词 Elliptic curve signing group individual signer collective signature group signature
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New Collective Signatures Based on the Elliptic Curve Discrete Logarithm Problem
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作者 Tuan Nguyen Kim Duy Ho Ngoc Nikolay A.Moldovyan 《Computers, Materials & Continua》 SCIE EI 2022年第10期595-610,共16页
There have been many digital signature schemes were developed based on the discrete logarithm problem on a finite field.In this study,we use the elliptic curve discrete logarithm problem to build new collective signat... There have been many digital signature schemes were developed based on the discrete logarithm problem on a finite field.In this study,we use the elliptic curve discrete logarithm problem to build new collective signature schemes.The cryptosystem on elliptic curve allows to generate digital signatures with the same level of security as other cryptosystems but with smaller keys.To extend practical applicability and enhance the security level of the group signature protocols,we propose two new types of collective digital signature schemes based on the discrete logarithm problem on the elliptic curve:i)the collective digital signature scheme shared by several signing groups and ii)the collective digital signature scheme shared by several signing groups and several individual signers.These two new types of collective signatures have combined the advantages of group digital signatures and collective digital signatures.These signatures have a fixed size and do not depend on the number of members participating in the creation of the final collective signature.One of the advantages of the proposed collective signature protocols is that they can be deployed on top of the available public key infrastructures. 展开更多
关键词 Elliptic curve signing group individual signer collective signature group signature
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SNSAlib:A python library for analyzing signed network
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作者 Ai-Wen Li Jun-Lin Lu +1 位作者 Ying Fan Xiao-Ke Xu 《Chinese Physics B》 2025年第3期64-75,共12页
The unique structure of signed networks,characterized by positive and negative edges,poses significant challenges for analyzing network topology.In recent years,various statistical algorithms have been developed to ad... The unique structure of signed networks,characterized by positive and negative edges,poses significant challenges for analyzing network topology.In recent years,various statistical algorithms have been developed to address this issue.However,there remains a lack of a unified framework to uncover the nontrivial properties inherent in signed network structures.To support developers,researchers,and practitioners in this field,we introduce a Python library named SNSAlib(Signed Network Structure Analysis),specifically designed to meet these analytical requirements.This library encompasses empirical signed network datasets,signed null model algorithms,signed statistics algorithms,and evaluation indicators.The primary objective of SNSAlib is to facilitate the systematic analysis of micro-and meso-structure features within signed networks,including node popularity,clustering,assortativity,embeddedness,and community structure by employing more accurate signed null models.Ultimately,it provides a robust paradigm for structure analysis of signed networks that enhances our understanding and application of signed networks. 展开更多
关键词 signed networks null models topology structure statistic analysis
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Influence of guidance signs on platform evacuation in suburban railway tunnel under smoke and obstacle environment
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作者 Yifan Zhuang Fan Wang +2 位作者 Yuanchun Huang Xiaomin Song Ya Rao 《High-Speed Railway》 2025年第1期1-16,共16页
Once a train stops in a tunnel section and requires emergency evacuation,the large distance between stations and long walking distances in the underground spaces of suburban railway systems pose potential risks to the... Once a train stops in a tunnel section and requires emergency evacuation,the large distance between stations and long walking distances in the underground spaces of suburban railway systems pose potential risks to the evacuation process on tunnel platforms,especially in complex environments.This study utilized Virtual Reality(VR)technology to construct a virtual experimental platform for tunnel evacuation in suburban railway systems,simulating different combinations of smoke and obstacle conditions.By requiring participants to wear VR glasses and walk on an omnidirectional treadmill for moving,as well as complete psychological questionnaires,the study reveals the influences of No Guiding(NG)signs,Wall-Guided(WG)signs,and Central axis Guidance(CG)signs on the movement abilities and psychological behaviors of participants contrastively.The results show that either smoke conditions or obstacle positions affect the mental stress of participants,and the guidance sign has a positive effect on reducing the mental stress.There is an inverse relationship between mental stress and movement abilities.WG and CG signs respectively lead participants to walk closer to walls and along the central axis,which is conducive to reducing the variation in participants’behavior characteristics when circumventing obstacles on the wall side or track side under smoke conditions,respectively.Additionally,CG signs reduce the speed fluctuations of participants before circumventing obstacles,improving the stability of the distance from the wall and speed under smoke conditions,compared to NG and WG signs.These findings contribute to understanding the evacuation psychological-behavioral-movement characteristics of pedestrians on evacuation platforms in suburban railway tunnels and provide a basis for improving the safety design of evacuation guidance signs. 展开更多
关键词 Tunnel evacuation platform Pedestrian safety VR experiment Guidance sign Suburban railway Emergency evacuation
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VTAN: A Novel Video Transformer Attention-Based Network for Dynamic Sign Language Recognition
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作者 Ziyang Deng Weidong Min +2 位作者 Qing Han Mengxue Liu Longfei Li 《Computers, Materials & Continua》 2025年第2期2793-2812,共20页
Dynamic sign language recognition holds significant importance, particularly with the application of deep learning to address its complexity. However, existing methods face several challenges. Firstly, recognizing dyn... Dynamic sign language recognition holds significant importance, particularly with the application of deep learning to address its complexity. However, existing methods face several challenges. Firstly, recognizing dynamic sign language requires identifying keyframes that best represent the signs, and missing these keyframes reduces accuracy. Secondly, some methods do not focus enough on hand regions, which are small within the overall frame, leading to information loss. To address these challenges, we propose a novel Video Transformer Attention-based Network (VTAN) for dynamic sign language recognition. Our approach prioritizes informative frames and hand regions effectively. To tackle the first issue, we designed a keyframe extraction module enhanced by a convolutional autoencoder, which focuses on selecting information-rich frames and eliminating redundant ones from the video sequences. For the second issue, we developed a soft attention-based transformer module that emphasizes extracting features from hand regions, ensuring that the network pays more attention to hand information within sequences. This dual-focus approach improves effective dynamic sign language recognition by addressing the key challenges of identifying critical frames and emphasizing hand regions. Experimental results on two public benchmark datasets demonstrate the effectiveness of our network, outperforming most of the typical methods in sign language recognition tasks. 展开更多
关键词 Dynamic sign language recognition TRANSFORMER soft attention attention-based visual feature aggregation
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Interpretative Challenges of the 'Missing Perilymph' Sign in PLF Diagnosis——A Letter To The Editor
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作者 Jamil Ammara 《Journal of Otology》 2025年第4期281-281,共1页
Dear Editor,I am responding to Zou and Li's,The missing perilymph sign on MRI indicates a perilymphatic fistula:A case report Zou J,Li H.Journal of Otology,2025, 20(1):1-4.https://doi.org/10.26599/JOTO.2025.954000... Dear Editor,I am responding to Zou and Li's,The missing perilymph sign on MRI indicates a perilymphatic fistula:A case report Zou J,Li H.Journal of Otology,2025, 20(1):1-4.https://doi.org/10.26599/JOTO.2025.9540001 proposing the"missing perilymph"sign on MRI as a novel radiological indicator of perilymphatic fistula(PLF).This study adds to the growing body of work seeking objective,non-invasive diagnostic methods for PLF,a condition that has long eluded definitive radiological confirmation.The avoidance of gadolinium contrast in the imaging technique is an additional strength,given increasing awareness of gadoliniumassociated risks (Starekova et al.,2024). 展开更多
关键词 perilymphatic fistula avoidance gadol perilymphatic fistula plf gadolinium contrast missing perilymph sign MRI diagnostic method
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Another example of Aslanger’s sign
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作者 Koji Takahashi Nobuhisa Yamamura +6 位作者 Mako Yoshino Daijiro Enomoto Hiroe Morioka Shigeki Uemura Takafumi Okura Tomoki Sakaue Katsuji Inoue 《Journal of Geriatric Cardiology》 2025年第4期455-457,共3页
The arterial pulse tapping artifact,known as Aslanger’s sign,is an electrocardiographic artifact resulting from the transmission of arterial pulsation onto the limb electrodes of the standard 12-lead electrocardiogra... The arterial pulse tapping artifact,known as Aslanger’s sign,is an electrocardiographic artifact resulting from the transmission of arterial pulsation onto the limb electrodes of the standard 12-lead electrocardiograph(ECG)which are placed near the radial or posterior tibial arteries.[1-16]This electromechanical artifact is of cardiac origin and is synchronous with the cardiac cycle.[17]Nearly all reported cases of Aslanger’s sign exhibit an unusual waveform morphology in all 12 leads except one limb lead.[1-14,16]However,we previously reported a case of Aslanger’s sign that showed distorted waveforms from the ST to TP segments observed only in five limb leads among 12 leads. 展开更多
关键词 leads electrocardiographic artifact limb electrodes aslanger's sign electromechanical artifact waveform morphology arterial pulse tapping artifactknown transmission arterial pulsation
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Reply to:Interpretative Challenges of the'Missing Perilymph'Sign in PLF Diagnosis——A Thoughtful Discussion
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作者 Jing Zou 《Journal of Otology》 2025年第4期282-282,共1页
Dear Editor,I am writing in response to Jamil's letter,"Interpretative Challenges of the Missing Perilymph'Sign in PLF Diagnosis."I concur with the author's emphasis on the necessity for cautious... Dear Editor,I am writing in response to Jamil's letter,"Interpretative Challenges of the Missing Perilymph'Sign in PLF Diagnosis."I concur with the author's emphasis on the necessity for cautious interpretation of low-signal areas as evidence of active perilymph leakage,requiring correlation with clinical findings,surgical confirmation,and longitudinal imaging changes. 展开更多
关键词 interpretative challenges PLF diagnosis perilymph leakagerequiring missing perilymph sign clinical findingssurgical clinical findings longitudinal imaging changes cautious interpretation
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Predefined-time controller design for a multiple space transportation robots system based on Lp-Norm-Normalized Sign Function
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作者 Ran TAO Yibo DING +1 位作者 Hanyu LI Xiaokui YUE 《Chinese Journal of Aeronautics》 2025年第2期432-444,共13页
This paper presents a predefined-time controller for Multiple Space transportation Robots System (MSRS), which can be applied in on-orbit assembly tasks to transport modules to pre-assembly configuration quickly. Firs... This paper presents a predefined-time controller for Multiple Space transportation Robots System (MSRS), which can be applied in on-orbit assembly tasks to transport modules to pre-assembly configuration quickly. Firstly, to simplify the analysis and design of predefined-time controller, a Predefined-time Stability Criterion is proposed in the form of Composite Lyapunov Function (CLF-PSC). Besides simplicity, the CLF-PSC also has the advantage of less conservativeness due to utilization of initial state information. Secondly, a concept of Lp-Norm-Normalized Sign Function (LPNNSF) is proposed based on the CLF-PSC. Different from traditional norm-normalized sign function, the Lp-norm of LPNNSF can be selected arbitrarily according to practical control task requirements, which means that the proposed LPNNSF is more generalized and more convenient for calculation. Thirdly, a predefined-time disturbance observer and predefined-time controller are designed based on the LPNNSF. The observer has the property of predefined-time convergence to achieve quicker and more accurate estimation of the lumped disturbance. The controller has less control input and chattering phenomenon than traditional predefined-time controller. In addition, by introducing the observer into the controller, the closed-loop system enjoys high precision and strong robustness. Finally, the effectiveness of the proposed controller is verified by numerical simulations. By employing the controller, the MSRS can carry assembly modules to the desired pre-assembly configuration accurately within predefined time. 展开更多
关键词 Multiple space transportation robots system On-orbit assemblyPredefined-time stability criterion Composite Lyapunov function Lp-Norm-Normalized sign Function Predefined-time controller
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Magnetic resonance cholangiopancreatography and laparoscopic bile duct exploration should be standard procedures for patients with the ice-breaking sign?
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作者 Lucia Mejuto Maria Delgado Luis R Rabago 《World Journal of Gastrointestinal Surgery》 2025年第11期12-16,共5页
The authors introduce a new magnetic resonance cholangiopancreatography(MRCP)radiologic feature,the“ice-breaking sign”(IBS),and present a retrospective case-control study comparing patients with common bile duct sto... The authors introduce a new magnetic resonance cholangiopancreatography(MRCP)radiologic feature,the“ice-breaking sign”(IBS),and present a retrospective case-control study comparing patients with common bile duct stones who exhibit the IBS with a control group without this sign.The two groups were matched using a propensity score based on patient age and sex.However,the matching process did not account for the size of the choledocholithiasis,which may represent a significant confounding factor.Both groups were not homogeneous.The authors advocate for the use of MRCP as the primary diagnostic tool to guide the decision.However,in clinical practice,MRCP availability is often limited,particularly when compared to endoscopic ultrasound,which may be more available.The authors compared the clinical course and therapeutic responses to cholangiopancreatography(ERCP)and laparoscopic common bile duct exploration(LCBDE)between the two groups.The results demonstrated a markedly low ERCP success rate in both the study and control,falling below international standards,whereas the success rate of LCBDE was only slightly reduced.Despite the study’s li-mitations and potential biases,the authors conclude that IBS is a valuable predictor for treatment planning and suggest that LCBDE should be considered the first-line approach.Despite its growing acceptance,LCBDE remains infeasible in many hospitals due to the steep learning curve. 展开更多
关键词 Ice breaking sign Magnetic resonance cholangiopancreatography CHOLEDOCHOLITHIASIS Laparoscopic bile duct exploration Common bile duct stones treatment Endoscopic retrograde cholangiopancreatography
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HIV-1暴露未感染人群DC-SIGN和DC-SIGNR基因多态性 被引量:1
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作者 王晓辉 胡鹏威 +2 位作者 陈琳 石向东 赵锦 《中国热带医学》 CAS 2010年第3期273-274,337,共3页
目的研究HIV-1高暴露未感染人群(ESN)、正常对照人群和HIV-1携带者DC-SIGN和DC-SIGNR基因型和基因频率分布,探讨这两个基因多态性与HIV-1不易感性的关系。方法应用PCR技术扩增两个基因颈区重复序列,以琼脂糖凝胶电泳区分两个基因不同重... 目的研究HIV-1高暴露未感染人群(ESN)、正常对照人群和HIV-1携带者DC-SIGN和DC-SIGNR基因型和基因频率分布,探讨这两个基因多态性与HIV-1不易感性的关系。方法应用PCR技术扩增两个基因颈区重复序列,以琼脂糖凝胶电泳区分两个基因不同重复序列的电泳图差异,以卡方检验分析基因型和基因频率分布差异。结果DC-SIGN在三组人群中以7/7型为主,三组人群共检出9个非7/7基因型,但DC-SIGN各基因型分布差异无统计学意义(P=0.648);DC-SIGNR具有高度多态性,7/5、5/5和6/7基因型的频率从ESN人群、健康对照人群和HIV-1携带者逐渐降低,同时5和6等位基因的频率也呈现均匀下降,但各基因型分布差异无统计学意义(P=0.782)。结论我国汉族人群DC-SIGN基因多态性变异很低,其对于今后HIV-1人群不易感性的研究意义不大;DC-SIGNR基因多态性对于HIV-1不易感性的意义尚需要大样本的验证或细胞生物学实验数据的支持。 展开更多
关键词 HIV-1 DC—sign DC—signR 基因多态性 易感性
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