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Zoological Research 2020年第4期41卷 423-430页

作者： zhong-yuan shen Dan Yu Xin Gao Fu-Tie Zhang Huan-Zhang Liu The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of HydrobiologyChinese Academy of SciencesWuhanHubei 430072China University of Chinese Academy of Sciences Beijing 100049China

The Chinese sturgeon(Acipenser sinensis Gray,1835)is a large anadromous fish species,which is under considerable threat due to dramatic declines in population numbers.In the current study,population genetic diversity and individual reproductive success were assessed using nuclear microsatellite markers(simple sequence repeat,SSR)and complete mitochondrial(mt DNA)genome analysis of juveniles born in 2014.Results showed the existence of size polymorphism in the mt DNA genome of Chinese sturgeon,which was caused by a repeat motif.Population genetic diversity was high based on both SSR(Ho:0.728±0.211;He:0.779±0.122)and mt DNA genome analyses(H:0.876±0.0035;Pi:0.0011±0.0010).A positive inbreeding coefficient(FIS:0.066±0.143)was also found,indicating the occurrence of inbreeding.Reconstruction of sibling groups identified 11 mothers and 11 fathers involved in reproduction of Chinese sturgeons in 2014.Variance in individual reproductive success was not significant,with reproductive success of parent fish instead shown to be relatively even(P=0.997>0.05),thus suggesting the absence of sweepstakes reproductive success(SRS).These results indicate that,in regard to conservation,loss of genetic diversity due to the effects of SRS is not of particular concern.However,we must focus on having an adequate number of adults and suitable environmental conditions to ensure that fish can reproduce.

关键词： instead absence Yangtze

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机器人产品质量安全监测预警平台研究及应用

科学技术与工程 2024年第4期24卷 1553-1560页

作者：钟远生陈向志唐力华高晓东广东产品质量监督检验研究院广州510670 国家市场监管重点实验室(智能机器人安全) 广州510670

机器人产品安全性随机器人数量增长和应用范围扩大而越受重视。为解决机器人安全数据缺乏导致机器人产品质量监管形式及方法受制约问题,设计了以数据为核心、应用为导向的预警系统架构,构建了机器人安全指标库、产品类型库、安全风险库... 详细信息

机器人产品安全性随机器人数量增长和应用范围扩大而越受重视。为解决机器人安全数据缺乏导致机器人产品质量监管形式及方法受制约问题,设计了以数据为核心、应用为导向的预警系统架构,构建了机器人安全指标库、产品类型库、安全风险库等机器人产品属性和安全属性数据库,研究了基于抽样检测数据、网络舆情数据、消费投诉数据的多源数据处理流程和方法,开发了机器人产品质量安全监测预警平台。该平台实现了机器人质量安全事件和信息的实时采集、智能评估、系统监测和及时预警,为其他工业产品基于大数据的质量监督提供方法参考。

关键词：机器人质量安全预警平台数据采集文本分类

Factors influencing the use of heart rate variability for evaluating autonomic nervous function in mind-body research

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实用心电学杂志 2017年第2期26卷 84-90页

作者： Shin Lin zhong-yuan shen Timothy Ross Department of Biophysical Research Center University of California Irvine 92697 Irvine California USA Qigong Research Institute Shanghai University of Traditional Chinese Medicine200030 Shanghai China Project Department Building Research Across Inter-Disciplinary Gaps (BRIDG) Program University of Washington98195 Seattle Washing-ton USA

心率变异性(HRV)分析是非侵入性评估自主神经功能的常用方法 .在许多研究中,低频变异性(LF,如通过快速傅立叶变换产生的功率谱中所示的0.15 Hz)作为副交感神经功能的指标.通过对15位心-身锻练习练者和20位非习练者的对照研究,我们发现... 详细信息

心率变异性(HRV)分析是非侵入性评估自主神经功能的常用方法 .在许多研究中,低频变异性(LF,如通过快速傅立叶变换产生的功率谱中所示的0.15 Hz)作为副交感神经功能的指标.通过对15位心-身锻练习练者和20位非习练者的对照研究,我们发现以下是影响HRV的重要因素.第一,呼吸周期的频率反映在由呼吸性窦性心律不齐(RS A)产生的功率谱中的峰值频率中.在涉及年轻受试者的情况下,即使以单一速率严格控制他们的呼吸,也能在功率谱中看到多个峰;第二,由RSA产生的HRV峰的大小取决于每次呼吸的潮气量和受试者的姿势;第三,在相同条件下,与年龄较大的受试者(年龄在50~70岁)相比,年轻受试者(年龄在20~25岁)通常显示更大的RSA峰值.这种效应常常掩盖了基于其他因素的差异,例如多年的心-身锻练.总之,这项研究表明了HRV分析用于评估自主神经功能的心-身研究可以作为一个有用的工具,但需注意必须采取措施控制所有上述因素.

关键词： heart rate variability respiratory sinus arrhythmia autonomic nervous function mind body research

Visible-frequency nonvolatile reconfigurable Janus metasurfaces for dual-wavelength-switched and spin-asymmetric holograms

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Photonics Research 2024年第2期12卷 356-368页

作者： HUAN yuan ZHEQIANG zhong BIN ZHANG College of Electronics and Information Engineering Sichuan UniversityChengdu 610064China Big Data Analysis and Fusion Application Technology Engineering Laboratory of Sichuan Province Chengdu 610065China

Janus metasurface holography with asymmetric transmission characteristics provides new degrees of freedom for multiplexing technologies.However,earlier metasurfaces with asymmetrical transmission faced limitations in terms of tunability and multifunctionality.In this study,we propose a metasurface color holographic encryption scheme with dynamic switching and asymmetric transmission at visible frequencies using a low-loss nonvolatile optical phase-change material,Sb_(2)S_(3).Using a modified holographic optimization strategy,we achieved highfidelity asymmetric holographic imaging of a nanostructured metasurface.By controlling the incident direction and wavelength of visible light,as well as the level of crystallization of Sb_(2)S_(3),this reconfigurable metasurface enables the precise manipulation of tunable color holographic image displays.In particular,in the semi-crystalline state of Sb_(2)S_(3),the encoded information can be securely encrypted using a two-channel color-holographic image,whereas only a preset camouflaged image is displayed in the crystalline or amorphous state of Sb_(2)S_(3).The proposed multiencrypted Janus metasurface provides a potential approach for dynamic holographic displays with ultrahigh capacity,holographic encryption,and information storage.

关键词： holographic asymmetric visible

Effects of longitudinal magnetic field on primary dendrite spacing and segregation of directionally solidified single crystal superalloy

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Progress in Natural Science:Materials International 2024年第1期34卷 26-36页

作者： Congjiang Zhang Yilin Zhou Chen shen Weili Ren Xiaotan yuan Biao Ding Haibiao Lu Zuosheng Lei Yunbo zhong Ang Zhang State Key Laboratory of Advanced Special Steel College of Materials Science and Engineering Shanghai University National Engineering Research Center for Magnesium Alloys Natural Key Laboratory of Advanced Casting Technologies College of Materials Science and EngineeringChongqing University

The primary dendrite spacing(PDS) and segregation of directionally solidified single crystal(SC) superalloy under the longitudinal magnetic field(LMF) were investigated based on the analysis of the whole cross-sectional microstructure at different solidification distances. The results show that the PDS under the LMF remains basically unchanged at different solidification distances, and it is greater than that under no LMF. With the increase of magnetic field intensity, the PDS increases and the macrosegregation decreases. The increasing PDS and reducing segregation under the LMF can be attributed to the increase of solute boundary layer, which expands the non-equilibrium freezing temperature range and brings the effective partition coefficient closer to 1. The increase of the solute enrichment layer thickness could be caused by the downward secondary circulation generated by the thermoelectric magnetic convection(TEMC) near the interface, which drives the migration of solutes towards the interdendritic region. This work not only clarifies the mechanism of LMF controlling PDS and reducing segregation by TEMC, but also provides theoretical guidance for producing high-quality SC superalloys using magnetic fields.

关键词： Primary dendrite spacing Segregation Single crystal superalloy Directional solidification Magnetic field Thermoelectric magnetic convection

A Lightweight Network with Dual Encoder and Cross Feature Fusion for Cement Pavement Crack Detection

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 255-273页

作者： zhong Qu Guoqing Mu Bin yuan School of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqing400065China School of Software Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China

Automatic crack detection of cement pavement chiefly benefits from the rapid development of deep learning,with convolutional neural networks(CNN)playing an important role in this field.However,as the performance of crack detection in cement pavement improves,the depth and width of the network structure are significantly increased,which necessitates more computing power and storage space.This limitation hampers the practical implementation of crack detection models on various platforms,particularly portable devices like small mobile devices.To solve these problems,we propose a dual-encoder-based network architecture that focuses on extracting more comprehensive fracture feature information and combines cross-fusion modules and coordinated attention mechanisms formore efficient feature fusion.Firstly,we use small channel convolution to construct shallow feature extractionmodule(SFEM)to extract low-level feature information of cracks in cement pavement images,in order to obtainmore information about cracks in the shallowfeatures of images.In addition,we construct large kernel atrous convolution(LKAC)to enhance crack information,which incorporates coordination attention mechanism for non-crack information filtering,and large kernel atrous convolution with different cores,using different receptive fields to extract more detailed edge and context information.Finally,the three-stage feature map outputs from the shallow feature extraction module is cross-fused with the two-stage feature map outputs from the large kernel atrous convolution module,and the shallow feature and detailed edge feature are fully fused to obtain the final crack prediction map.We evaluate our method on three public crack datasets:DeepCrack,CFD,and Crack500.Experimental results on theDeepCrack dataset demonstrate the effectiveness of our proposed method compared to state-of-the-art crack detection methods,which achieves Precision(P)87.2%,Recall(R)87.7%,and F-score(F1)87.4%.Thanks to our lightweight crack detectionmodel,the parameter count of the mo

关键词： Shallow feature extraction module large kernel atrous convolution dual encoder lightweight network crack detection

Chipless textile electronics: human body-coupled fiber for wireless energy harvesting and signal transmission

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Science China Materials 2024年第7期67卷 2367-2368页

作者： Yixuan Wang Zuqing yuan Guozhen shen School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081China

Wearable technology is rapidly advancing through the integration of electronic devices and textiles,enabling intelligent interaction between clothing and the surrounding environment.Some electronics are specifically designed to provide functions such as sensing,computation,display,and communication.However,traditional wearable devices that rely on rigid von Neumann architectures and incorporate silicon chips face challenges in seamless integration,energy efficiency,and comfort[1–3].Difficulties arise when attempting to integrate complex circuits and electronic components,which are traditionally relied upon for signal modulation,into soft fibers[4,5].Recent reports have begun to explore alternative architectures for wearable devices that can incorporate electronics into a single fiber[6].However,this process presents challenges in simultaneously controlling energy capture and release within a single fiber.

关键词： fiber signal energy

Prevalence of prolonged grief disorder and its symptoms among bereaved individuals in China:a systematic review and meta-analysis

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General Psychiatry 2024年第2期37卷 177-188页

作者： Meng-Di yuan Jun-Fa Liu Bao-Liang zhong Research Center for Psychological and Health Sciences China University of Geosciences(Wuhan)WuhanHubeiChina Department of Psychiatry Wuhan Mental Health CentreWuhanHubeiChina

Background The prevalence of prolonged grief disorder(PGD)and its symptoms among the bereaved population in China vary considerably.Aims This meta-analysis aims to estimate the prevalence of PGD and its symptoms among bereaved individuals in China.Methods We conducted a literature search in major Chinese and English databases from their inception to 4 October 2023,for cross-sectional studies on the prevalence of PGD or its symptoms in bereaved Chinese individuals.The risk of bias of the included studies and certainty of the evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data(‘JBI checklist’)and the Grading of Recommendations,Assessment,Development and Evaluations(GRADE),respectively.The‘metaprop’package in R V.4.1.2 was used to synthesise the prevalence.Results A total of 28 studies involving 10994 bereaved individuals were included in the analysis,with JBI checklist scores between 3 and 7.The combined prevalence(95%confidence interval)of PGD and its symptoms was 8.9%(4.2%to 17.6%)and 32.4%(18.2%to 50.8%),respectively.PGD and its symptoms were most prevalent among those who had lost their only child(22.7%)and those bereaved by earthquakes(80.4%),respectively.The GRADE system assigned a very low certainty level to the evidence for the pooled prevalence of PGD and its symptoms.Conclusions The pooled prevalence of PGD and its symptoms indicate a potential high need for grief counselling services among bereaved individuals in China.This need is particularly pronounced in those who have lost their only child and those bereaved due to earthquakes.Further methodologically rigorous studies are needed to provide more accurate prevalence estimates.PROSPERO registration number CRD42023432553.

关键词： symptoms prevalence analysis

Numerical simulation of transient characteristics in a bulb turbine during the load rejection process

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Journal of Hydrodynamics 2024年第1期36卷 170-183页

作者： Yue Lu Yu-quan Zhang zhong-wei He yuan Zheng College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China College of Energy and Electrical Engineering Hohai UniversityNanjing210098China Huadong Engineering Corporation Ltd. Hangzhou311122China

To evaluate the safety of the bulb tubular turbine,the dynamic hydraulic characteristics of a hydropower station system during the load rejection process are studied through numerical simulations and a prototype test.In the developed model,a dynamic grid technology(DGT)controls the closure of the guide vane and the blade,whilst the moment balance equation and the user-defined function(UDF)provide the runner’s rotation speed.The 3-D transient simulation method can well predict the rotation speed and mass flow curves in the state of load rejection.The simulation outcomes of the system performance are basically consistent with the measurement data of the prototype.As observed,the runner is subjected to the reversely increased torque and axial force,the system is in a braking phase,and the maximum speed peaks at 144.6%of the rated speed.Moreover,the internal flow of the runner is greatly affected by the closure of the guide vane,and the draft tube forms an eccentric spiral vortex rope.It breaks downstream,aggravating the instability of the draft tube.Overall,the transient characteristics span for the first five seconds,demonstrating the importance of establishing an efficient governing controller.The obtained results are useful for designing the turbine’s flow channel with a double regulating function and comprehending the turbine’s transient characteristics.

关键词： Bulb tubular turbine load rejection numerical simulation dynamic grid prototype test

Effect of solvent on the initiation mechanism of living anionic polymerization of styrene:A computational study

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Chinese Journal of Chemical Engineering 2024年第5期69卷 135-142页

作者： shen Li Yin-Ning Zhou zhong-Xin Liu Zheng-Hong Luo School of Chemical Engineering and Technology Hainan UniversityHaikou 570228China Department of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China

For living anionic polymerization(LAP),solvent has a great influence on both reaction mechanism and kinetics.In this work,by using the classical butyl lithium-styrene polymerization as a model system,the effect of solvent on the mechanism and kinetics of LAP was revealed through a strategy combining density functional theory(DFT)calculations and kinetic modeling.In terms of mechanism,it is found that the stronger the solvent polarity,the more electrons transfer from initiator to solvent through detailed energy decomposition analysis of electrostatic interactions between initiator and solvent molecules.Furthermore,we also found that the stronger the solvent polarity,the higher the monomer initiation energy barrier and the smaller the initiation rate coefficient.Counterintuitively,initiation is more favorable at lower temperatures based on the calculated results ofΔG_(TS).Finally,the kinetic characteristics in different solvents were further examined by kinetic modeling.It is found that in benzene and n-pentane,the polymerization rate exhibits first-order kinetics.While,slow initiation and fast propagation were observed in tetrahydrofuran(THF)due to the slow free ion formation rate,leading to a deviation from first-order kinetics.

关键词： Living anionic polymerization Solvent effect Reaction kinetics Computational chemistry Mathematical modeling Kinetic modeling