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Stimulated Raman scattering tomography for rapid three-dimensional chemical imaging of cells and tissue

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Establishment and application of a surrogate model for human Ebola virus disease in BSL-2 laboratory

Advanced Photonics 2024年第2期6卷 20-31页

作者： weiqi wang Zhiwei Huang National University of Singapore College of Design and EngineeringOptical Bioimaging LaboratoryDepartment of Biomedical EngineeringSingapore

Three-dimensional(3D)imaging is essential for understanding intricate biological and biomedical systems,yet live cell and tissue imaging applications still face challenges due to constrained imaging speed and strong scattering in turbid ***,we present a unique phase-modulated stimulated Raman scattering tomography(PM-SRST)technique to achieve rapid label-free 3D chemical imaging in cells and *** accomplish PM-SRST,we utilize a spatial light modulator to electronically manipulate the focused Stokes beam along the needle Bessel pump beam for SRS tomography without the need for mechanical z *** demonstrate the rapid 3D imaging capability of PM-SRST by real-time monitoring of 3D Brownian motion of polystyrene beads in water with 8.5 Hz volume rate,as well as the instant biochemical responses to acetic acid stimulants in MCF-7 ***,combining the Bessel pump beam with a longer wavelength Stokes beam(NIR-II window)provides a superior scattering resilient ability in PM-SRST,enabling rapid tomography in deeper tissue *** PM-SRST technique providestwofold enhancement in imaging depth in highly scattering media(e.g.,polymer beads phantom and biotissue like porcine skin and brain tissue)compared with conventional point-scan *** also demonstrate the rapid 3D imaging ability of PM-SRST by observing the dynamic diffusion and uptake processes of deuterium oxide molecules into plant *** rapid PM-SRST developed can be used to facilitate label-free 3D chemical imaging of metabolic activities and functional dynamic processes of drug delivery and therapeutics in live cells and tissue.

关键词： stimulated Raman scattering tomography deep tissue Raman imaging spatial light modulation

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Virologica Sinica 2024年第3期39卷 434-446页

作者： Wanying Yang Wujian Li Wujie Zhou Shen wang weiqi wang Zhenshan wang Na Feng Tiecheng wang Ying Xie Yongkun Zhao Feihu Yan Xianzhu Xia Hebei Key Lab of Laboratory Animal Science Department of Laboratory Animal ScienceHebei Medical UniversityShijiazhuang050017China Key Laboratory of Jilin Province for Zoonosis Prevention and Control Changchun Veterinary Research InstituteChinese Academy of Agricultural SciencesChangchun130122China College of Veterinary Medicine Jilin UniversityChangchun130062China College of Veterinary Medicine Jilin Agricultural UniversityChangchun130118China

The Ebola virus(EBOV)is a member of the Orthoebolavirus genus,Filoviridae family,which causes severe hemorrhagic diseases in humans and non-human primates(NHPs),with a case fatality rate of up to 90%.The development of countermeasures against EBOV has been hindered by the lack of ideal animal models,as EBOV requires handling in biosafety level(BSL)-4 ***,accessible and convenient animal models are urgently needed to promote prophylactic and therapeutic approaches against *** this study,a recombinant vesicular stomatitis virus expressing Ebola virus glycoprotein(VSV-EBOV/GP)was constructed and applied as a surrogate virus,establishing a lethal infection in *** infection with VSV-EBOV/GP,3-week-old female Syrian hamsters exhibited disease signs such as weight loss,multi-organ failure,severe uveitis,high viral loads,and developed severe systemic diseases similar to those observed in human EBOV *** animals succumbed at 2–3 days post-infection(dpi).Histopathological changes indicated that VSV-EBOV/GP targeted liver cells,suggesting that the tissue tropism of VSV-EBOV/GP was comparable to wild-type EBOV(WT EBOV).Notably,the pathogenicity of the VSV-EBOV/GP was found to be species-specific,age-related,gender-associated,and challenge ***,equine anti-EBOV immunoglobulins and a subunit vaccine were validated using this ***,this surrogate model represents a safe,effective,and economical tool for rapid preclinical evaluation of medical countermeasures against EBOV under BSL-2 conditions,which would accelerate technological advances and breakthroughs in confronting Ebola virus disease.

关键词： Ebola virus(EBOV) Recombinant vesicular stomatitis virus Pathogenicity Syrian hamster Surrogate models Vaccine evaluation and drug screening

Research on Track Fastener Service Status Detection Based on Improved Yolov4 Model

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Journal of Transportation Technologies 2024年第2期14卷 212-223页

作者： Jing He weiqi wang Nengpu Yang College of Electrical and Information Engineering Hunan University of Technology Zhuzhou Hunan College of Railway Transportation Hunan University of Technology Zhuzhou Hunan

As an important part of railway lines, the healthy service status of track fasteners was very important to ensure the safety of trains. The application of deep learning algorithms was becoming an important method to realize its state detection. However, there was often a deficiency that the detection accuracy and calculation speed of model were difficult to balance, when the traditional deep learning model is used to detect the service state of track fasteners. Targeting this issue, an improved Yolov4 model for detecting the service status of track fasteners was proposed. Firstly, the Mixup data augmentation technology was introduced into Yolov4 model to enhance the generalization ability of model. Secondly, the MobileNet-V2 lightweight network was employed in lieu of the CSPDarknet53 network as the backbone, thereby reducing the number of algorithm parameters and improving the model’s computational efficiency. Finally, the SE attention mechanism was incorporated to boost the importance of rail fastener identification by emphasizing relevant image features, ensuring that the network’s focus was primarily on the fasteners being inspected. The algorithm achieved both high precision and high speed operation of the rail fastener service state detection, while realizing the lightweight of model. The experimental results revealed that, the MAP value of the rail fastener service state detection algorithm based on the improved Yolov4 model reaches 83.2%, which is 2.83% higher than that of the traditional Yolov4 model, and the calculation speed was improved by 67.39%. Compared with the traditional Yolov4 model, the proposed method achieved the collaborative optimization of detection accuracy and calculation speed.

关键词： Yolov4 Model Service Status of Track Fasteners Detection and Recognition Data Augmentation Lightweight Network Attention Mechanism

地效环境下悬停状态直升机旋翼桨/涡干扰噪声特性

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航空学报 2024年第12期45卷 67-81页

作者：王伟琪陈希招启军南京航空航天大学直升机动力学全国重点实验室南京210016

为掌握直升机贴地飞行时旋翼噪声辐射特性,首先基于可压缩雷诺平均Navier-Stokes方程和Ffowcs Williams-Hawkings方程发展了一套适用于地效状态旋翼/机身干扰的气动与噪声分析方法,通过Lynx尾桨地面效应试验及NASA旋翼/机身干扰试验与... 详细信息

为掌握直升机贴地飞行时旋翼噪声辐射特性,首先基于可压缩雷诺平均Navier-Stokes方程和Ffowcs Williams-Hawkings方程发展了一套适用于地效状态旋翼/机身干扰的气动与噪声分析方法,通过Lynx尾桨地面效应试验及NASA旋翼/机身干扰试验与计算结果的对比,验证了所建立方法的可靠性。然后,开展了机身和桨毂对旋翼流场的影响研究,发现机身改变了旋翼的气动载荷分布并提高中等阶次(8~12阶次)的噪声辐射水平;桨毂会削弱桨叶中段(r=0.4R~0.7R,R为旋翼半径)的噪声贡献。最后,研究了不同离地高度(h)时旋翼的气动与噪声特性,发现存在一个出现桨/涡干扰噪声的“临界离地高度”。结果表明:旋翼拉力和机身升力随h增大而减小;当h>1.8R时地面效应的影响可以忽略;当h=0.6R时地面和机身的双重阻塞作用会改变旋翼入流情况,尤其在桨尖区域诱发剧烈的载荷波动,并在特征观测点接收到明显的桨/涡干扰噪声;根据时/频特性给出了本文的“临界离地高度”约为0.7R,为直升机贴地飞行时抑制噪声提供了参考。

关键词：旋翼气动噪声 FW-H方程旋翼/机身干扰地面效应桨/涡干扰噪声

电液3-UPS/S并联稳定平台参数振动特性分析

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振动与冲击 2024年第5期43卷 52-61页

作者：袁晓明王维锜庞浩东张立杰燕山大学河北省重型机械流体动力传输与控制实验室河北秦皇岛066004 燕山大学先进锻压成形技术与科学教育部重点实验室河北秦皇岛066004

针对电液3-UPS/S并联稳定平台驱动液压缸的压力脉动所产生的参数振动,建立了稳定平台的参数振动方程并利用多尺度法求解了主共振响应与组合共振响应的一次近似解;分析了主共振与组合共振响应特性以及振动幅值在初始工作空间内的变化规律... 详细信息

针对电液3-UPS/S并联稳定平台驱动液压缸的压力脉动所产生的参数振动,建立了稳定平台的参数振动方程并利用多尺度法求解了主共振响应与组合共振响应的一次近似解;分析了主共振与组合共振响应特性以及振动幅值在初始工作空间内的变化规律,最后采用四阶龙格库塔法与模态试验对参数振动模型进行验证。结果表明:数值解与理论解之间的最大误差为4.20%,固有频率理论值与试验值之间的最大误差为4.66%,可验证参数振动模型的正确性。

关键词：电液3-UPS/S并联稳定平台压力脉动参数振动多尺度法振动特性

教育元宇宙的伦理隐忧及其消解之策——基于伯格曼的技术哲学视角

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中国人民大学教育学刊 2024年第3期 121-132页

作者：王苇琪南京师范大学道德教育研究所南京210097

教育元宇宙是元宇宙技术与教育相互建构下的创新性成果,也是未来网络教育发展的新形态,它突破了时空边界与物理条件的限制,开拓了超越现实的教育情境,让学生的多样化发展成为可能。然而教育元宇宙也隐藏着伦理风险,主要体现在师生虚拟... 详细信息

教育元宇宙是元宇宙技术与教育相互建构下的创新性成果,也是未来网络教育发展的新形态,它突破了时空边界与物理条件的限制,开拓了超越现实的教育情境,让学生的多样化发展成为可能。然而教育元宇宙也隐藏着伦理风险,主要体现在师生虚拟主体性的膨胀、教师角色的边缘化以及学生真实生命体验的遮蔽,从伯格曼的技术哲学角度来看,教育元宇宙处于“装置”的范式之下,它会否定人在教育实践活动中的在场参与性,将教育异化为学习消费,使教育目的与手段分离。但人在“装置”面前并非无能为力,通过对现实中身体主体的关照,以“聚焦物”连接人与教育情境,并鼓励师生对教育实践的“在场参与”,在一定程度上可以消解教育元宇宙的伦理风险,实现教育的价值追求。

关键词：教育元宇宙伦理风险伯格曼技术哲学

新时代老年体育服务数字化治理的逻辑架构、发展张力与未来路径

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阜阳师范大学学报（社会科学版） 2024年第4期 141-149页

作者：王暐琦王路震阜阳师范大学体育学院安徽阜阳236037

数字技术赋能老年体育服务治理意义重大,为破解老年体育服务治理中的诸多难题,运用文献资料、逻辑分析等方法,对我国老年体育服务数字化治理进行研究,认为:数据处理是老年体育服务数字治理的要素基础,技术嵌入是老年体育服务数字化治理... 详细信息

数字技术赋能老年体育服务治理意义重大,为破解老年体育服务治理中的诸多难题,运用文献资料、逻辑分析等方法,对我国老年体育服务数字化治理进行研究,认为:数据处理是老年体育服务数字治理的要素基础,技术嵌入是老年体育服务数字化治理的工具支撑,平台构建是老年体育服务数字化治理的形式载体。在当前老年体育服务数字化治理改革中,数据要素存在明显短板,技术洼地影响场景适配,平台构建与实践桎梏存在明显冲突。要实现新时代老年体育服务数字化治理改革的可持续发展,一要以数据为核心,夯实老年体育服务数字化治理的基础;二要以技术为支撑,激活老年体育服务数字化治理的潜力;三要以平台为枢纽,不断优化老年体育服务数字化治理的流程。

关键词：体育服务数字化治理路径

基于POI的城市餐饮供给空间异质性研究--以青岛市为例

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鲁东大学学报（自然科学版） 2024年第3期40卷 226-234页

作者：王玮琦王铁曲阜师范大学地理与旅游学院山东日照276826

餐饮是城市旅游的核心要素之一,本文基于青岛市餐饮POI(point of interest)、人口密度、交通站点等数据,运用核密度分析、平均最近邻等分析方法,从不同维度对青岛市餐饮业的空间分布模式和集聚状态进行了探查,探讨了其空间异质性的主要... 详细信息

餐饮是城市旅游的核心要素之一,本文基于青岛市餐饮POI(point of interest)、人口密度、交通站点等数据,运用核密度分析、平均最近邻等分析方法,从不同维度对青岛市餐饮业的空间分布模式和集聚状态进行了探查,探讨了其空间异质性的主要驱动因素。研究结果如下。(1)青岛市各类餐饮业空间分布不均衡,中心城区连片分布,形成“一主四副”的多中心发展格局。不同类型餐饮设施空间分布趋势差异明显:中餐厅高度集中分布于市南区、市北区及其交界处,呈现连片分布的特点;外国餐厅高度集中分布于市南区东部、城阳区北部,总体形成“两主三副”的空间发展格局;快餐厅高密度区集中于市南区与市北区连接形成椭圆状区域及李沧区南部,呈连片分布。(2)青岛市餐饮业空间异质性主要受人口、经济、交通、城市基础设施、旅游资源五类要素影响,人口规模越大、交通越便捷、城市基础设施越好,餐饮业的分布越密集。

关键词： POI 餐饮业青岛市空间异质性影响因素

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镁合金建筑模板的表面化学镀与耐蚀性能

电镀与精饰 2024年第10期46卷 34-41页

作者：孙伟清陈微王玮琪杭州科技职业技术学院城建学院浙江杭州311402 浙江久正工程检测有限公司浙江杭州311401 浙江理工大学材料科学与工程学院浙江杭州311121

采用化学镀的方法在镁合金建筑模板表面分别制备了单一Sn膜、单一Zn膜和复合Sn-Zn膜,对比分析了pH、温度和膜层数对镁合金表面膜层显微形貌和电化学性能的影响。结果表明:对于单一膜,在pH值为6.0、温度为75℃时制备的单一Sn膜和在pH值为... 详细信息

采用化学镀的方法在镁合金建筑模板表面分别制备了单一Sn膜、单一Zn膜和复合Sn-Zn膜,对比分析了pH、温度和膜层数对镁合金表面膜层显微形貌和电化学性能的影响。结果表明:对于单一膜,在pH值为6.0、温度为75℃时制备的单一Sn膜和在pH值为9.5、温度为75℃时制备的单一Zn膜都具有较好成膜质量;当膜层数为9时,复合Sn-Zn膜完全覆盖镁合金基体且膜层成膜质量较好。相较于镁合金基体,单一Sn膜、单一Zn膜、复合Sn-Zn膜的腐蚀电位都发生正向移动,腐蚀电流密度发生不同程度减小,复合Sn-Zn膜的腐蚀电位最正、腐蚀电流密度最小。在镁合金基体表面化学镀单一Sn膜、单一Zn膜、复合Sn-Zn膜都有助于提升镁合金的耐蚀性能,且复合Sn-Zn膜对基体的保护作用要优于单一Sn膜、单一Zn膜。

关键词： AZ91镁合金建筑模板化学镀 Sn-Zn复合膜耐蚀性能