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A Deformable Network with Attention Mechanism for Retinal Vessel Segmentation

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Journal of Beijing Institute of Technology 2024年第3期33卷 186-193页

作者： Xiaolong Zhu Wenjian li Weihang Zhang Dongwei li huiqi li School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

The intensive application of deep learning in medical image processing has facilitated the advancement of automatic retinal vessel segmentation research.To overcome the limitation that traditional U-shaped vessel segmentation networks fail to extract features in fundus image sufficiently,we propose a novel network(DSeU-net)based on deformable convolution and squeeze excitation residual module.The deformable convolution is utilized to dynamically adjust the receptive field for the feature extraction of retinal vessel.And the squeeze excitation residual module is used to scale the weights of the low-level features so that the network learns the complex relationships of the different feature layers efficiently.We validate the DSeU-net on three public retinal vessel segmentation datasets including DRIVE,CHASEDB1,and STARE,and the experimental results demonstrate the satisfactory segmentation performance of the network.

关键词： retinal vessel segmentation deformable convolution attention mechanism deep learning

A Modified CycleGAN for Multi-Organ Ultrasound Image Enhancement via Unpaired Pre-Training

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Journal of Beijing Institute of Technology 2024年第3期33卷 194-203页

作者： Haonan Han Bingyu Yang Weihang Zhang Dongwei li huiqi li School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China School of Medical Technology Beijing Institute of TechnologyBeijing 100081China

Handheld ultrasound devices are known for their portability and affordability,making them widely utilized in underdeveloped areas and community healthcare for rapid diagnosis and early screening.However,the image quality of handheld ultrasound devices is not always satisfactory due to the limited equipment size,which hinders accurate diagnoses by doctors.At the same time,paired ultrasound images are difficult to obtain from the clinic because imaging process is complicated.Therefore,we propose a modified cycle generative adversarial network(cycleGAN) for ultrasound image enhancement from multiple organs via unpaired pre-training.We introduce an ultrasound image pre-training method that does not require paired images,alleviating the requirement for large-scale paired datasets.We also propose an enhanced block with different structures in the pre-training and fine-tuning phases,which can help achieve the goals of different training phases.To improve the robustness of the model,we add Gaussian noise to the training images as data augmentation.Our approach is effective in obtaining the best quantitative evaluation results using a small number of parameters and less training costs to improve the quality of handheld ultrasound devices.

关键词： ultrasound image enhancement handheld devices unpaired images pre-train and finetune cycleGAN

Mesenchymal stem cell-derived exosomes: Versatile nanomaterials for skin wound treatment

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Nano Research 2024年第4期17卷 2836-2856页

作者： Yuzhen Xiao Hexi li Junhui Zhang Songyun Yang Chunsen Zhang Yizhou Huang Xin Tang huiqi Xie Department of Orthopedic Surgery and Orthopedic Research Institute Laboratory of Stem Cell and Tissue EngineeringState Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu 610041China West China School of Basic Medical Sciences and Forensic Medicine Sichuan UniversityChengdu 610041China West China School of Public Health and West China Fourth Hospital Sichuan UniversityChengdu 610041China Sports Medicine Center West China HospitalSichuan UniversityChengdu 610041China

Accumulating studies reveal that mesenchymal stem cells(MSCs)promote skin wound healing mainly through the paracrine effects.Exosomes,one of the crucial paracrine mediators in wound healing,are cell-derived nanosized membranous vesicles containing diverse bioactive cargoes.With the potent ability of modulating skin cell behaviors,MSC-derived exosomes(MSC-Exos)are regarded as a promising nanomaterial for regenerative wound therapy.Under hostile conditions,MSC-Exos are efficient in protecting skin cells from severe damage and restoring their function.According to recent studies,MSC-Exos possess remarkable pro-healing effects in a variety of skin wounds,typically resulting in increased wound closure,inhibited scar tissue formation,and better restoration of skin function.To further enhance the therapeutic potential of MSC-Exos,the development of applicable pretreatment strategies and the optimization of exosome delivery are under intensive investigation.Herein,we summarize current research progress of MSC-Exos for skin wound treatment,with an emphasis on the biological effects of these nanovesicles,the repair mechanisms,and future challenges in clinical translation.

关键词： exosomes mesenchymal stem cells diabetic wounds burn wounds scar wound healing

Intelligent Recognition Using Ultralight Multifunctional Nano‑Layered Carbon Aerogel Sensors with Human‑like Tactile Perception

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Nano-Micro Letters 2024年第1期16卷 172-186页

作者： huiqi Zhao Yizheng Zhang Lei Han Weiqi Qian Jiabin Wang Heting Wu Jingchen li Yuan Dai Zhengyou Zhang Chris RBowen Ya Yang CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro‑Nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400People’s Republic of China Tencent Robotics X Shenzhen 518054People’s Republic of China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049People’s Republic of China Department of Mechanical Engineering University of BathBath BA27AKUK Center on Nanoenergy Research School of Physical Science and TechnologyGuangxi UniversityNanning 530004People’s Republic of China

Humans can perceive our complex world through multi-sensory fusion.Under limited visual conditions,people can sense a variety of tactile signals to identify objects accurately and rapidly.However,replicating this unique capability in robots remains a significant challenge.Here,we present a new form of ultralight multifunctional tactile nano-layered carbon aerogel sensor that provides pressure,temperature,material recognition and 3D location capabilities,which is combined with multimodal supervised learning algorithms for object recognition.The sensor exhibits human-like pressure(0.04–100 kPa)and temperature(21.5–66.2℃)detection,millisecond response times(11 ms),a pressure sensitivity of 92.22 kPa^(−1)and triboelectric durability of over 6000 cycles.The devised algorithm has universality and can accommodate a range of application scenarios.The tactile system can identify common foods in a kitchen scene with 94.63%accuracy and explore the topographic and geomorphic features of a Mars scene with 100%accuracy.This sensing approach empowers robots with versatile tactile perception to advance future society toward heightened sensing,recognition and intelligence.

关键词： Multifunctional sensor Tactile perception Multimodal machine learning algorithms Universal tactile system Intelligent object recognition

Precipitation Microphysical Characteristics of Typhoon Ewiniar(2018) before and after Its Final Landfall over Southern China

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Advances in Atmospheric Sciences 2023年第6期40卷 1005-1020页

作者： Lu FENG Hui XIAO Xiantong liU Sheng HU huiqi li liusi XIAO Xiao HAO Guangzhou Institute of Tropical and Marine Meteorology China Meteorological AdministrationGuangzhou 510641China Guangdong Provincial Key Laboratory of Regional Numerical Weather Prediction China Meteorological AdministrationGuangzhou 510641China Guangzhou Meteorological Observatory China Meteorological AdministrationGuangzhou 511430China

In this paper, the evolution of the microphysical characteristics in different regions(eyewall, inner core, and outer rainbands) and different quadrants [downshear left(DL), downshear right(DR), upshear left(UL), and upshear right(UR)]during the final landfall of Typhoon Ewiniar(2018) is analyzed using two-dimensional video disdrometer and S-band polarimetric radar data collected in Guangdong, China. Due to the different types of underlying surfaces, the periods before landfall(mainly dominated by underlying sea surface) and after landfall(mainly dominated by underlying land surface) are also analyzed. Both before landfall and after landfall, the downshear quadrants had the dominate typhoon precipitation. The outer rainbands had more graupel than the inner core, resulting in a larger radar reflectivity, differential reflectivity, specific differential phase shift, and mass-weighted mean diameter below the melting layer. Compared with other regions, the eyewall region had the smallest mean logarithmic normalized intercept parameter before landfall and the smallest mean mass-weighted mean diameter and the largest mean logarithmic normalized intercept parameter after landfall. The hydrometeor size sorting was obvious in the eyewall and inner core(especially in the eyewall) after landfall. A high concentration of large raindrops fell in the DL quadrant, and more small raindrops fell in the UR quadrant. Although the icephase process and warm rain process were both important in the formation of tropical cyclone precipitation, the warm rain process(ice-phase process) contributed more liquid water before landfall(after landfall). This investigation provides a reference for improving the microphysical parameterization scheme in numerical models.

关键词： tropical cyclone precipitation microphysics raindrop size distribution southern China

Graphdiyne scaffold anchored highly dispersed ruthenium nanoparticles as an efficient cathode catalyst for rechargeable li-CO_(2) battery

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Chinese Chemical Letters 2024年第1期35卷 552-557页

作者： Yiru Ma huiqi Qu Wenna Wang Ziyang Guo Yueqin Yu Feng liu Bin Yu Minge Tian Zhenjiang li Bin li Lei Wang College of Chemistry and Molecular Engineering State Key Laboratory Base of Eco-Chemical EngineeringInternational Science and Technology Cooperation Base of Eco-Chemical Engineering and Green ManufacturingQingdao University of Science and TechnologyQingdao 266042China College of Materials Science and Engineering Qingdao University of Science and TechnologyQingdao 266042China College of Environment and Safety Engineering Qingdao University of Science and TechnologyQingdao 266042China College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China Biomedical Sensing Engineering Technology Research Center Shandong UniversityJi'nan 250100China Scientific Green(Shandong)Environmental Technology Co. Ltd.Jining Economic Development ZoneJining 272499China

lithium (li)-CO_(2) battery is rising as an attractive energy-storage system with the competence of CO_(2) conversion/fixation. However, its practical development is seriously hindered by the high overpotential. Herein, a rational design on a highly catalytic li-CO_(2) battery electrode built by graphdiyne powder as a multi-functional laminar scaffold with anchored highly dispersed Ru nanoparticles is explored. The strong interaction between the abundant acetylenic bond sites of graphdiyne scaffold and Ru nanoparticles can effectively promote the electrochemical progress and reduce the voltage polarization. The unique channels architecture of the cathodic catalyst with enough space not only accelerates CO_(2) diffusion and electrons/li+ transport, but also allows a large amount of accommodation for discharged product (li2CO3) to assure an advanced capacity. The corresponding li-CO_(2) battery displays an advanced discharged capacity of 15,030 mAh/g at 500 mA/g, great capacity retention of 8873 mAh/g at 2 A/g, high coulombic efficiency of 97.6% at 500 mA/g and superior life span for 120 cycles with voltage gap of 1.67 V under a restricted capacity of 1000 mAh/g at 500 mA/g. Ex/in-situ studies prove that synergy between Ru nanoparticles and acetylene bonds of GDY can boost the round-trip CO_(2)RR and CO_(2)ER kinetics.

关键词： Nanopores li-CO_(2)battery Anchored Ru nanoparticles Graphdiyne Synergistic effect

Optically pumped Milliwatt Whispering-Gallery microcavity laser

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light(Science & Applications) 2023年第10期12卷 2154-2162页

作者： huiqi li Zhaocong Wang Lei Wang Yang Tan Feng Chen School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinanChina

Whispering-gallery-mode microcavity lasers possess remarkable characteristics such as high Q factors and compact geometries,making them an essential element in the evolution of microlasers.However,solid-state whispering-gallery-mode lasers have previously suffered from low output power and limited optical conversion efficiency,hindering their applications.Here,we present the achievement of milliwatt laser emissions at a wavelength of 1.06µm from a solid-state whispering-gallery-mode laser.To accomplish this,we construct a whispering-gallery-mode microcavity(with a diameter of 30µm)using a crystalline Nd:YAG thin film obtained through carbon-implantation enhanced etching of a Nd:YAG crystal.This microcavity laser demonstrates a maximum output power of 1.12 mW and an optical conversion efficiency of 12.4%.Moreover,our unique eccentric microcavity design enables efficient coupling of free-space pump light,facilitating integration with a waveguide.This integration allowed for single-wavelength laser emission from the waveguide,achieving an output power of 0.5 mW and an optical conversion efficiency of 6.18%.Our work opens up new possibilities for advancing solid-state whispering-gallery-mode lasers,providing a viable option for compact photonic sources.

关键词： laser pumped waveguide

Piezo机械敏感性离子通道在骨关节系统中的作用

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中国修复重建外科杂志 2024年第2期38卷 240-248页

作者：陈国辉李亚星张晖解慧琪四川大学华西医院骨科成都610041 四川大学华西医院骨科研究所成都610041 四川大学华西医院国家重点实验室干细胞与组织工程研究室成都610041

目的总结Piezo机械敏感性离子通道在骨关节系统中的作用,以期为后续研究提供参考。方法广泛查阅国内外相关文献,对Piezo离子通道的结构特点、门控机制、激活剂与阻滞剂及其在骨关节系统中的作用进行总结。结果骨关节系统是机体主要承重... 详细信息

目的总结Piezo机械敏感性离子通道在骨关节系统中的作用,以期为后续研究提供参考。方法广泛查阅国内外相关文献,对Piezo离子通道的结构特点、门控机制、激活剂与阻滞剂及其在骨关节系统中的作用进行总结。结果骨关节系统是机体主要承重和运动组织,其感知并响应机械刺激的能力是维持骨关节正常生理功能的保障之一,许多骨关节疾病的发生、发展与异常机械负荷有紧密关系。目前研究显示Piezo机械敏感性离子通道通过响应拉伸刺激、细胞Ca^(2+)内流信号调节向成骨方向分化;并影响成骨细胞的增殖与迁移,通过成骨细胞-破骨细胞之间细胞交流维持骨内稳态。同时,Piezo1蛋白可以通过其宿主细胞间接参与调控破骨细胞的形成及活性,进而调节骨重塑过程。而Piezo1离子通道在机械刺激时,通过调节Akt、Wnt1信号通路表达,维持骨内稳态;针对Piezo1、2离子通道对高应变机械信号的敏感性,介导的Ca^(2+)内流以及炎症信号使得软骨细胞中Piezo1离子通道机械转导敏感性增加的特性,有望成为靶向性防治骨关节炎的新切入点。但机械刺激如何调控骨关节生理/病理过程仍待阐明。结论Piezo机械敏感性离子通道赋予了骨关节系统感知并响应机械应力的重要能力,在其细胞命运转归、骨骼发育、骨与软骨稳态维持等方面扮演关键的机械传感作用。

关键词：骨关节系统 Piezo 机械敏感性离子通道机械转导

基于GRU和MOGWO的软基水闸底板脱空动力学智能反演

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应用基础与工程科学学报 2024年第1期32卷 85-99页

作者：李火坤唐义员黄伟柳波王文韬朱慧琪南昌大学工程建设学院江西南昌330031

软基水闸在水流侵蚀等因素作用下易发生底板脱空现象,极大地威胁水闸的安全运行.针对软基水闸底板脱空检测问题,提出一种基于门控循环单元(Gate Recurrent Unit, GRU)神经网络代理模型和多目标灰狼算法(Multi-Objective Grey Wolf Optim... 详细信息

软基水闸在水流侵蚀等因素作用下易发生底板脱空现象,极大地威胁水闸的安全运行.针对软基水闸底板脱空检测问题,提出一种基于门控循环单元(Gate Recurrent Unit, GRU)神经网络代理模型和多目标灰狼算法(Multi-Objective Grey Wolf Optimizer, MOGWO)的软基水闸底板脱空动力学反演方法.基于GRU神经网络构建表征软基水闸结构模态参数与脱空参数间非线性关系的数学代理模型,基于水闸结构固有频率、归一化振型建立软基水闸脱空参数反演的多目标优化函数,并采用MOGWO优化算法求解多目标优化问题的Pareto最优解.将所提方法应用于室内软基水闸物理模型两种脱空工况的反演计算.GRU神经网络代理模型精度优于多层前馈(Back Propagation, BP)神经网络代理模型及三阶多项式响应面模型,且反演脱空面积和模型实际脱空面积的相对误差分别为6.76%、5.58%,反演效果明显优于单目标反演方法.

关键词：软基水闸底板脱空反演动力学方法代理模型 GRU神经网络 MOGWO优化算法