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Sensitivity Improvements for Picosecond Ultrasonic Thickness Measurements in Gold and Tungsten Nanoscale Films

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Nanomanufacturing and Metrology 2024年第2期7卷 1-12页

作者： Jiaqi dong Chengyuan Yao Yuanhao Zhu Shaojie Li Bowen Liu JinTao Fan Chunguang hu Youjian Song Minglie hu Key Laboratory of Opto-Electronic Information Science and Technology of Ministry of Education School of Precision Instruments and Opto-Electronics EngineeringTianjin UniversityTianjin 300072China State Key Laboratory of Precision Measuring Technology and Instruments Tianjin UniversityTianjin 300072China

Picosecond ultrasonics,as a nondestructive and noncontact method,can be employed for nanoscale metallic film thickness *** sensitivity of the system,which determines the measurement precision and practicability of this technique,is often limited by the weak intensity of the ultrasonic *** solve this problem,we investigate the distinct mechanisms involved in picosecond ultrasonic thickness measurement for two types of metals,namely tungsten(W)and gold(Au).For thickness measurement in W films,theory and simulation show that optimizing the pump and probe laser wavelengths,which determine the intensity and shape of the ultrasonic signal,is critical to improving measurement sensitivity,while for Au film measurements,where acoustic-induced beam distortion is dominant,the signal intensity can be optimized by selecting an appropriate aperture size and sample *** above approaches are validated in experiments.A dual-wavelength pump-probe system is constructed based on a passively mode-locked ytterbium-doped fiber *** smoothing method and multipeak Gaussian fitting are employed for the extraction of ultrasonic *** measurement precision is achieved in a series of W and Au films with thicknesses of 43-750 *** work can be applied to various high-precision,noncontact measurements of metal film thickness in the semiconductor industry.

关键词： Picosecond ultrasonics Thickness measurement Optical pump-probe Beam distortion technique

Introducing electrolytic electrochemical polymerization for constructing protective layers on Ni-rich cathodes of Li-ion batteries

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Rare Metals 2024年第6期43卷 2536-2545页

作者： Lin-Tao Dou Bei Li Hao-Long Nie dong-dong Xiao Chao-Qun Shang Xiao-Min Wang Zhan-hui Zhang Katerina E.Aifantis Pu hu School of Materials Science and Engineering Wuhan Institute of TechnologyWuhan 430205China huairou Division Institute of PhysicsChinese Academy of SciencesBeijing 101400China Department of Mechanical and Aerospace Engineering University of FloridaGainesvilleFL 32603USA

LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)is the most promising cathode for high-energy Li-ion batteries,despite its poor cycling stability that originates from the reactions that occur with the ***,to solve this interfacial issue,a facile electrolytic electrochemical polymerization process was introduced in this paper,and a uniform conductive electrolyte interface(polyaniline)was successfully constructed on the surface of the NCM811 porous electrode(PANI-NCM),which facilitated the charge transfer during charge/*** side reactions at the interface between the cathode and the electrolyte are suppressed,and thereby,the cycling performance and rate capability are considerably ***-NCM delivers an initial capacity of 157.2 mAh·g^(-1)as well as excellent cyclability(capacity retention of 88%after 500 cycles at 2C),whereas the capacity of the bare NCM811 has dropped to 31.3 mAh·g^(-1).In addition,polypyrrole and polythiophene also can be formed through electrolytic electrochemical polymerization process,which provides a practicable tactic to modify the interfacial stability of cathodes for high-energy Li-ion batteries.

关键词： Lithium-ion battery Ni-rich cathode In-situ polymerization Conductive polymer Electrochemical performance

Modeling drug-induced mitochondrial toxicity with human primary cardiomyocytes

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Science China(Life Sciences) 2024年第2期67卷 301-319页

作者： Xiaoli Tang Hong Liu Rongjia Rao Yafei huang Mengqi dong Miaomiao Xu Shanshan Feng xun Shi Li Wang Zengwu Wang Bingying Zhou State Key Laboratory of Cardiovascular Disease Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100037China Department of Epidemiology Cardiovascular Institute and Fuwai HospitalChinese Academy of Medical Science&Peking Union Medical CollegeBeijing 100037China Shenzhen Key Laboratory of Cardiovascular Disease Fuwai Hospital Chinese Academy of Medical SciencesShenzhenShenzhen 518020China

Mitochondrial toxicity induced by therapeutic drugs is a major contributor for cardiotoxicity,posing a serious threat to pharmaceutical industries and patients’***,mitochondrial toxicity testing is not incorporated into routine cardiac safety screening *** accurately model native human cardiomyocytes,we comprehensively evaluated mitochondrial responses of adult human primary cardiomyocytes(h PCMs)to a nucleoside analog,remdesivir(RDV).Comparison of their response to human pluripotent stem cell-derived cardiomyocytes revealed that the latter utilized a mitophagy-based mitochondrial recovery response that was absent in h ***,action potential duration was elongated in h PCMs,reflecting clinical incidences of RDV-induced QT *** a screen for mitochondrial protectants,we identified mitochondrial ROS as a primary mediator of RDV-induced *** study demonstrates the utility of h PCMs in the detection of clinically relevant cardiac toxicities,and offers a framework for h PCM-based high-throughput screening of cardioprotective agents.

关键词： remdesivir mitochondrial toxicity cardiotoxicity human primary cardiomyocytes high-throughput screening

Bariatric surgery and diabetes:Current challenges and perspectives

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World Journal of Diabetes 2024年第8期15卷 1692-1703页

作者： Yan-Fei He Xiao-dong hu Jun-Qiang Liu hu-Ming Li Shuang-Feng Lu Health Management Center The Sixth Medical CenterChinese PLA General HospitalBeijing 100048China Department of Endocrinology The Sixth Medical CenterChinese PLA General HospitalBeijing 100048China Department of Thoracic Surgery The Sixth Medical CenterChinese PLA General HospitalBeijing 100048China Department of Respiratory Medicine The Sixth Medical CenterChinese PLA General HospitalBeijing 100048China

Diabetes mellitus(DM)and obesity have become public issues of global *** surgery for the treatment of obesity combined with type 2 DM has been shown to be a safe and effective approach;however,there are limited studies that have systematically addressed the challenges of surgical treatment of obesity combined with *** this review,we summarize and answer the most pressing questions in the field of surgical treatment of obesity-associated DM.I believe that our insights will be of great help to clinicians in their daily practice.

关键词： Bariatric surgery Diabetes mellitus Obesity Metabolic surgery Challenge

Machine-learning-based models assist the prediction of pulmonary embolism in autoimmune diseases: A retrospective, multicenter study

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中华医学杂志(英文版) 2024年第15期137卷 1811-1822页

作者： hu Ziwei hu Yangyang Zhang Shuoqi dong Li Chen Xiaoqi Yang huiqin Su Linchong Hou Xiaoqiang huang Xia Shen Xiaolan Ye Cong Tu Wei Chen Yu Chen Yuxue Cai Shaozhe Zhong Jixin dong Lingli Department of Rheumatology and Immunology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei China Department of Radiology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei China Department of Rheumatology and Immunology Jingzhou Central Hospital Yangtze University Jinzhou Hubei China Department of Rheumatology and Immunology Zhongnan Hospital Wuhan University Wuhan Hubei China Department of Rheumatology Wuhan No.Hospital Wuhan Hubei China Department of Rheumatology Minda Hospital of Hubei Minzu University Enshi Hubei China Department of Rheumatology and Immunology The First College of Clinical Medical Science China Three Gorges University Yichang Hubei China

Background: Pulmonary embolism (PE) is a severe and acute cardiovascular syndrome with high mortality among patients with autoimmune inflammatory rheumatic diseases (AIIRDs). Accurate prediction and timely intervention play a pivotal role in enhancing survival rates. However, there is a notable scarcity of practical early prediction and risk assessment systems of PE in patients with ***: In the training cohort, 60 AIIRD with PE cases and 180 age-, gender-, and disease-matched AIIRD non-PE cases were identified from 7254 AIIRD cases in Tongji Hospital from 2014 to 2022. Univariable logistic regression (LR) and least absolute shrinkage and selection operator (LASSO) were used to select the clinical features for further training with machine learning (ML) methods, including random forest (RF), support vector machines (SVM), neural network (NN), logistic regression (LR), gradient boosted decision tree (GBDT), classification and regression trees (CART), and C5.0 models. The performances of these models were subsequently validated using a multicenter validation ***: In the training cohort, 24 and 13 clinical features were selected by univariable LR and LASSO strategies, respectively. The five ML models (RF, SVM, NN, LR, and GBDT) showed promising performances, with an area under the receiver operating characteristic (ROC) curve (AUC) of 0.962-1.000 in the training cohort and 0.969-0.999 in the validation cohort. CART and C5.0 models achieved AUCs of 0.850 and 0.932, respectively, in the training cohort. Using D-dimer as a pre-screening index, the refined C5.0 model achieved an AUC exceeding 0.948 in the training cohort and an AUC above 0.925 in the validation cohort. These results markedly outperformed the use of D-dimer levels ***: ML-based models are proven to be precise for predicting the onset of PE in patients with AIIRD exhibiting clinical suspicion of *** Registration: ***: ChiCTR2200059599.

关键词： Autoimmune inflammatory rheumatic diseases Pulmonary embolism Predictive model Machine learning

ARGA-Unet:Advanced U-net segmentation model using residual grouped convolution and attention mechanism for brain tumor MRI image segmentation

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虚拟现实与智能硬件（中英文） 2024年第3期6卷 203-216页

作者： Siyi xun Yan ZHANG Sixu DUAN Mingwei WANG Jiangang CHEN Tong TONG Qinquan GAO Chantong LAM Menghan hu Tao TAN Faculty of Applied Sciences Macao Polytechnic UniversityMacao 999078China Jinan Branch of China Telecom Co.Ltd. Jinan 250000China School of Physics and Electronics Shandong Normal UniversityJinan 250000China Department of Dardiovascular Medicine Affiliated Hospital of Hangzhou Normal UniversityHangzhou 310000China Clinical School of Medicine Hangzhou Normal UniversityHangzhou 310000China Hangzhou Institute of Cardiovascular Diseases Hangzhou 310000China Shanghai Key Laboratory of Multidimensional Information Processing Shanghai 200000China School of Communication&Electronic Engineering East China Normal UniversityShanghai 200000China Engineering Research Center of Traditional Chinese Medicine Intelligent Rehabilitation Ministry of EducationShanghai 200000China College of Physics and Information Engineering Fuzhou UniversityFuzhou 350000China

Background Magnetic resonance imaging(MRI)has played an important role in the rapid growth of medical imaging diagnostic technology,especially in the diagnosis and treatment of brain tumors owing to its non invasive characteristics and superior soft tissue ***,brain tumors are characterized by high non uniformity and non-obvious boundaries in MRI images because of their invasive and highly heterogeneous *** addition,the labeling of tumor areas is time-consuming and *** To address these issues,this study uses a residual grouped convolution module,convolutional block attention module,and bilinear interpolation upsampling method to improve the classical segmentation network *** influence of network normalization,loss function,and network depth on segmentation performance is further *** In the experiments,the Dice score of the proposed segmentation model reached 97.581%,which is 12.438%higher than that of traditional U-net,demonstrating the effective segmentation of MRI brain tumor *** In conclusion,we use the improved U-net network to achieve a good segmentation effect of brain tumor MRI images.

关键词： Brain tumor MRI U-net Segmentation Attention mechanism Deep learning

Robust video question answering via contrastive cross-modality representation learning

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Science China(Information Sciences) 2024年第10期 211-226页

作者： xun YANG Jianming ZENG Dan GUO Shanshan WANG Jianfeng dong Meng WANG School of Information Science and Technology University of Science and Technology of China Institute of Artificial Intelligence Hefei Comprehensive National Science Center School of Computer Science and Information Engineering Hefei University of Technology Institutes of Physical Science and Information Technology Anhui University School of Computer Science and Technology Zhejiang Gongshang University

Video question answering(VideoQA) is a challenging yet important task that requires a joint understanding of low-level video content and high-level textual semantics. Despite the promising progress of existing efforts, recent studies revealed that current VideoQA models mostly tend to over-rely on the superficial correlations rooted in the dataset bias while overlooking the key video content, thus leading to unreliable results. Effectively understanding and modeling the temporal and semantic characteristics of a given video for robust VideoQA is crucial but, to our knowledge, has not been well investigated. To fill the research gap, we propose a robust VideoQA framework that can effectively model the cross-modality fusion and enforce the model to focus on the temporal and global content of videos when making a QA decision instead of exploiting the shortcuts in datasets. Specifically, we design a self-supervised contrastive learning objective to contrast the positive and negative pairs of multimodal input, where the fused representation of the original multimodal input is enforced to be closer to that of the intervened input based on video perturbation. We expect the fused representation to focus more on the global context of videos rather than some static keyframes. Moreover, we introduce an effective temporal order regularization to enforce the inherent sequential structure of videos for video representation. We also design a Kullback-Leibler divergence-based perturbation invariance regularization of the predicted answer distribution to improve the robustness of the model against temporal content perturbation of videos. Our method is model-agnostic and can be easily compatible with various VideoQA backbones. Extensive experimental results and analyses on several public datasets show the advantage of our method over the state-of-the-art methods in terms of both accuracy and robustness.

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Flexible capacitive pressure sensor based on interdigital electrodes with porous microneedle arrays for physiological signal monitoring

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Nanotechnology and Precision Engineering 2024年第1期7卷 18-31页

作者： Jiahui Xu Minghao Wang Minyi Jin Siyan Shang Chuner Ni Yili hu xun Sun Jun Xu Bowen Ji Le Li Yuhua Cheng Gaofeng Wang School of Electronics&Information MOE Engineering Research Center of Smart Microsensors and MicrosystemsHangzhou Dianzi UniversityHangzhou 310018China Wenzhou Institute of Hangzhou Dianzi University Wenzhou 310018China Key Laboratory of Intelligent Operation and Maintenance Technology&Equipment for Urban Rail Transit of Zhejiang Province College of EngineeringInstitute of Precision Machinery and Smart StructureZhejiang Normal UniversityJinhua 321004China Institute of Guizhou Aerospace Measuring and Testing Technology Guiyang 550009China Unmanned System Research Institute Northwestern Polytechnical UniversityXi’an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China

Flexible pressure sensors have many potential applications in the monitoring of physiological signals because of their good biocompatibil-ity and ***,their relatively low sensitivity,linearity,and stability have hindered their large-scale commercial ***,aﬂexible capacitive pressure sensor based on an interdigital electrode structure with two porous microneedle arrays(MNAs)is *** porous substrate that constitutes the MNA is a mixed product of polydimethylsiloxane and *** to its porous and interdigital structure,the maximum sensitivity(0.07 kPa-1)of a porous MNA-based pressure sensor was found to be seven times higher than that of an imporous MNA pressure sensor,and it was much greater than that of aﬂat pressure sensor without a porous MNA ***-element analysis showed that the interdigital MNA structure can greatly increase the strain and improve the sensitivity of the *** addition,the porous MNA-based pressure sensor was found to have good stability over 1500 loading cycles as a result of its bilayer parylene-enhanced conductive electrode *** importantly,it was found that the sensor could accurately monitor the motion of aﬁnger,wrist joint,arm,face,abdomen,eye,and Adam’s ***,preliminary semantic recognition was achieved by monitoring the movement of the Adam’s ***,multiple pressure sensors were integrated into a 33 array to detect a spatial pressure distribu-×*** to the sensors reported in previous works,the interdigital electrode structure presented in this work improves sensitivity and stability by modifying the electrode layer rather than the dielectric layer.

关键词： Capacitive pressure sensor Microneedle array Porous PDMS Interdigital electrode

An Efficient Optimization Design Framework for Low-Resistance Shape of Bionic Amphibious Robot

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China Ocean Engineering 2024年第1期38卷 117-128页

作者： ZHANG Dai-yu ZHANG Man-yu WANG Zhi-dong ZHENG Wen-sheng LING Hong-jie hu Jun-ming School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

To realize the low-resistance shape optimization design of amphibious robots,an efficient optimization design framework is proposed to improve the geometric deformation flexibility and optimization *** the proposed framework,the free-form deformation parametric model of the flat slender body is established and an analytical calculation method for the height constraints is *** method is introduced to carry out the high-precision resistance calculation and a constrained Kriging-based optimization method is built to improve the optimization efficiency by circularly infilling the new sample points which satisfying the ***,the shape of an amphibious robot example is optimized to get the low-resistance shape and the results demonstrate that the presented optimization design framework has the advantages of simplicity,flexibility and high efficiency.

关键词： amphibious robot optimization method free-form deformation CFD-based hydrodynamic calculation