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Journal of Environmental Sciences 2024年第4期138卷 266-276页

作者： xu Liu xun Wang Dingyong Wang College of Resources and Environment Southwest UniversityChongqing 400715China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

The tree ring has been regarded as an emerging archive to reconstruct historical atmospheric mercury(Hg)trends,but with the large knowledge gaps in the reliability.In this study,we comprehensively evaluated the Hg source,radial translocation and age effect of Masson pine(Pinus massoniana)tree ring at Mt.Jinyun in Chongqing,to assess the suitability of such tree ring as the archive of atmospheric Hg.Results showed that distinct variabilities among Masson pine tree-ring Hg concentration profiles.The Hg concentration significantly increased along with stem height(P<0.05),indicating the Hg in tree rings mainly derived from foliage uptake atmospheric Hg.We found a distinct age effect that the tree ring of young trees had the higher Hg concentration.Besides,we used the advection-diffusion model to demonstrate how Hg concentration shifted by the advection or/and diffusion in tree rings.The modeling results showed that the advection induced radial translocation during the young growth period of tree was a plausible mechanism to result in the tree-ring Hg record largely different from the trend of anthropogenic Hg emissions in Chongqing.We finally suggest that in further Hg dendrochemistry,better discarding the tree-ring Hg profile of the young growth period to reduce impacts of the radial translocation and age effect.

关键词： Masson pine Tree-ring mercury Radial translocation Tree age effect

Superior compound coatings prepared by low-temperature vanadium-nitrocarburizing duplex treatment

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Rare Metals 2024年第4期43卷 1828-1835页

作者： Gen Jin Fang-Fang xu xun-xun Hu Yue xu School of Chemistry Beihang University Guobiao (Beijing) Testing and Certification Co. Ltd School of Materials Science and Engineering Beihang University

Superior compound coatings were prepared on CK45 steel surface by vanadium-nitrocarburizing duplex treatment in low-temperature salt bath.In this study,the microhardness,the phase constitution and the compositional distribution in the coatings prepared under different conditions were systematically characterized.The results indicated that the reactions among activated vanadium,carbon and nitrogen atoms occurred on the steel surface,leading to the formation of compound coatings composed of outermost and compound layers.The mechanism for the formation of compound layer as well as the growth kinetics of the layer was also discussed.Upon the duplex treatment,the wear and corrosion resistances of steel surface were significantly improved.It was found that the growth kinetics of compound layer obeyed the parabolic law,with the activation energy of 122.82 kJ·mol-1.

关键词： Vanadium-nitrocarburizing duplex treatment Compound coatings Microstructure Formation mechanism Growth kinetics

FaSRnet:a feature and semantics refinement network for human pose estimation

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 513-526页

作者： Yuanhong ZHONG Qianfeng xu Daidi ZHONG xun YANG Shanshan WANG School of Microelectronics and Communication Engineering Chongqing UniversityChongqing 400044China Bioengineering College of Chongqing University Chongqing UniversityChongqing 400044China School of Information Science and Technology University of Science and Technology of ChinaHefei 230039China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230039China

Due to factors such as motion blur,video out-of-focus,and occlusion,multi-frame human pose estimation is a challenging task.Exploiting temporal consistency between consecutive frames is an efficient approach for addressing this issue.Currently,most methods explore temporal consistency through refinements of the final heatmaps.The heatmaps contain the semantics information of key points,and can improve the detection quality to a certain extent.However,they are generated by features,and feature-level refinements are rarely considered.In this paper,we propose a human pose estimation framework with refinements at the feature and semantics levels.We align auxiliary features with the features of the current frame to reduce the loss caused by different feature distributions.An attention mechanism is then used to fuse auxiliary features with current features.In terms of semantics,we use the difference information between adjacent heatmaps as auxiliary features to refine the current heatmaps.The method is validated on the large-scale benchmark datasets PoseTrack2017 and PoseTrack2018,and the results demonstrate the effectiveness of our method.

关键词： Human pose estimation Multi-frame refinement Heatmap and offset estimation Feature alignment Multi-person

Challenging anticoagulation therapy for multiple primary malignant tumors combined with thrombosis:A case report and review of literature

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World Journal of Clinical Cases 2024年第9期12卷 1704-1711页

作者： Jia-Xin Chen Ling-Ling xu Jing-Ping Cheng xun-Hua xu Department of Gerontology China Resources and Wisco General HospitalWuhan University of Science and TechnologyWuhan 430080Hubei ProvinceChina Medical College Wuhan University of Science and TechnologyWuhan 430065Hubei ProvinceChina Department of Gerontology China Resources and Wisco General HospitalWuhan 430080Hubei ProvinceChina Department of Radiology China Resources and Wisco General HospitalWuhan 430080Hubei ProvinceChina

BACKGROUND Venous thromboembolism significantly contributes to patient deterioration and mortality.Management of its etiology and anticoagulation treatment is intricate,necessitating a comprehensive consideration of various factors,including the bleeding risk,dosage,specific anticoagulant medications,and duration of therapy.Herein,a case of lower extremity thrombosis with multiple primary malignant tumors and high risk of bleeding was reviewed to summarize the shortcomings of treatment and prudent anticoagulation experience.CASE SUMMARY An 83-year-old female patient was admitted to the hospital due to a 2-wk history of left lower extremity edema that had worsened over 2 d.Considering her medical history and relevant post-admission investigations,it was determined that the development of left lower extremity venous thrombosis and pulmonary embolism in this case could be attributed to a combination of factors,including multiple primary malignant tumors,iliac venous compression syndrome,previous novel coronavirus infection,and inadequate treatment for prior thrombotic events.However,the selection of appropriate anticoagulant medications,determination of optimal drug dosages,and establishment of an appropriate duration of anticoagulation therapy were important because of concurrent thrombocytopenia,decreased quantitative fibrinogen levels,and renal insufficiency.CONCLUSION Anticoagulant prophylaxis should be promptly initiated in cases of high-risk thrombosis.Individualized anticoagulation therapy is required for complex thrombosis.

关键词： Venous thromboembolism Cancer-associated thrombosis Anticoagulation therapy iliac vein compression syndrome COVID-19 Thrombocytopenia Case report

A calibration and compensation method for an industrial robot with high accuracy harmonic reducers

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Science China(Technological Sciences) 2024年第3期67卷 725-739页

作者： ZHAO YiYang LIU xun CAO JiaBin LIU JinYu xu Yan YAN WeiXin School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Computer and Control Engineering Northeast Forestry UniversityHarbin 150040China

Industrial serial robots need high stiffness to keep absolute pose accuracy and meet the requirements in practical applications. However, the weak stiffness feature of robot joints and the payloads affected on robot end-effector, which will also increase the pose error of robot. Especially, the existing calibration methods often consider under no-payload condition without discussing the payload state. In this paper, we report a new industrial serial robot composed by a new harmonic reducer: Model-Y, based on high accuracy and high stiffness, and a kinematic parameter calibration algorithm which is based on a harmonic reducer forcedeformation model. To decrease the accuracy effects of payload, an iterative calibration method for kinematic parameters with payload situation was proposed. Simulation and experiments are conducted to verify the effectiveness of the proposed calibration method using the self-developed industrial serial robot. The results show a remarkably improved accuracy in absolute position and orientation with the robot's payload range. The position mean error has 70% decreased to 0.1 mm and the orientation mean error diminished to less than 0.01° after calibration with compensation. Additionally, online linear and circular tests are carried out to evaluate the position error of the robot during large-scale spatial and low-speed continuous movement. The accuracy is consistent with the previous calibration results, indicating the effectiveness and advantages of the proposed strategy in this article.

关键词： industrial serial robot Model-Y harmonic calibration stiffness model online compensation

Recent advances in bioinspired vision systems with curved imaging structures

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Rare Metals 2024年第4期43卷 1407-1434页

作者： Ze-Ping He xun Han Wen-Qiang Wu Zhang-Sheng xu Cao-Feng Pan CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-Nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of Sciences School of Nanoscience and Technology University of Chinese Academy of Sciences ZJU-Hangzhou Global Scientific and Technological Innovation Center School of Micro-Nano ElectronicsZhejiang University Institute of Microscale Optoelectronics Shenzhen University

Limited by the planar imaging structure,the commercial camera needs to introduce additional optical elements to compensate for the curved focal plane to match the planar image sensor.This results in a complex and bulky structure.In contrast,biological eyes possess a simple and compact structure due to their curved imaging structure that can directly match with the curved focal plane.Inspired by the structures and functions of biological eyes,curved vision systems not only improve the image quality,but also offer a variety of advanced functions.Here,we review the recent advances in bioinspired vision systems with curved imaging structures.Specifically,we focus on their applications in implementing different functions of biological eyes,as well as the emerging curved neuromorphic imaging systems that incorporate bioinspired optical and neuromorphic processing technologies.In addition,the challenges and opportunities of bioinspired curved imaging systems are also discussed.

关键词： Bioinspired Curved vision system Compound eye Chambered eye Neuromorphic

Corrosion behavior of pure metals(Ni and Ti)and alloys(316H SS and GH3535)in liquid GaInSn

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Nuclear Science and Techniques 2024年第3期35卷 70-83页

作者： Jian-Hui Yu Hong-Xia xu Xiang-Xi Ye Bin Leng Han-xun Qiu Xing-Tai Zhou School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

In this study,the interactions between a Ga-based liquid metal,GaInSn,and several metal materials,including pure metals(Ni and Ti)and alloys(316H stainless steel(SS)and GH3535),at 650℃were investigated.The aim was to evaluate the corrosion performance and select a suitable candidate material for use as a molten salt manometer diaphragm in thermal energy storage systems.The results indicated that the alloys(316H SS and GH3535)exhibited less corrosion than pure metals(Ni and Ti)in liquid GaInSn.Ga-rich binary intermetallic compounds were found to form on the surfaces of all the tested metal materials exposed to liquid GaInSn,as a result of the decomposition of liquid GaInSn and its reaction with the constituent elements of the metal materials.The corrosion mechanism for all the tested materials exposed to liquid GaInSn was also investigated and proposed,which may aid in selecting the optimal candidate material when liquid GaInSn is used as the pressure-sensing medium.

关键词： Metal materials Liquid GaInSn Corrosion Intermetallic compounds Thermal energy storage systems

Role of the portal system in liver regeneration:From molecular mechanisms to clinical management

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Liver Research 2024年第1期8卷 1-10页

作者： Hanzhi xu xun Qiu Zhoucheng Wang Kai Wang Yawen Tan Fengqiang Gao Marcos Vinicius Perini Xiao xu Zhejiang University School of Medicine HangzhouZhejiangChina Key Laboratory of Integrated Oncology and Intelligent Medicine of Zhejiang Province HangzhouZhejiangChina Department of Surgery University of MelbourneAustin HealthHeidelbergVictoriaAustralia

The liver has a strong regenerative capacity that ensures patient recovery after hepatectomy and liver transplantation.The portal system plays a crucial role in the dual blood supply to the liver,making it a significant factor in hepatic function.Several surgical strategies,such as portal vein ligation,associating liver partition and portal vein ligation for staged hepatectomy,and dual vein embolization,have high-lighted the portal system's importance in liver regeneration.Following hepatectomy or liver trans-plantation,the hemodynamic properties of the portal system change dramatically,triggering regeneration via shear stress and the induction of hypoxia.However,excessive portal hyperperfusion can harm the liver and negatively affect patient outcomes.Furthermore,as the importance of the gut-liver axis has gradually been revealed,the effect of metabolites and cytokines from gut microbes carried by portal blood on liver regeneration has been acknowledged.From these perspectives,this review outlines the molecular mechanisms of the portal system's role in liver regeneration and summarizes therapeutic strategies based on the portal system intervention to promote liver regeneration.

关键词： Portal system Liver regeneration Hemodynamic properties Gut microbiota Therapeutic strategies

Sorl1 knockout inhibits expression of brain-derived neurotrophic factor:involvement in the development of late-onset Alzheimer's disease

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Neural Regeneration Research 2024年第7期19卷 1602-1607页

作者： Mingri Zhao xun Chen Jiangfeng Liu Yanjin Feng Chen Wang Ting xu Wanxi Liu Xionghao Liu Mujun Liu Deren Hou Department of Neurology The Third Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina Center for Medical Genetics&Hunan Key Laboratory of Medical Genetics School of Life SciencesCentral South UniversityChangshaHunan ProvinceChina Department of Cell Biology School of Life SciencesCentral South UniversityChangshaHunan ProvinceChina

Sortilin-related receptor 1(SORL1)is a critical gene associated with late-onset Alzheimer’s disease.SORL1 contributes to the development and progression of this neurodegenerative condition by affecting the transport and metabolism of intracellularβ-amyloid precursor protein.To better understand the underlying mechanisms of SORL1 in the pathogenesis of late-onset Alzheimer s disease,in this study,we established a mouse model of SorI1 gene knockout using cluste red regularly inters paced short palindro mic repeats-associated protein 9 technology.We found that Sorl1-knocko ut mice displayed deficits in learning and memory.Furthermore,the expression of brain-derived neurotrophic factor was significantly downregulated in the hippocampus and co rtex,and amyloidβ-protein deposits were observed in the brains of 5orl1-knockout mice.In vitro,hippocampal neuronal cell synapses from homozygous Sorl1-knockout mice were impaired.The expression of synaptic proteins,including Drebrin and NR2B,was significantly reduced,and also their colocalization.Additionally,by knocking out the Sorl1 gene in N2a cells,we found that expression of the N-methyl-D-aspartate receptor,NR2B,and cyclic adenosine monophosphate-response element binding protein was also inhibited.These findings suggest that SORL1 participates in the pathogenesis of late-onset Alzheimer s disease by regulating the N-methyl-D-aspartate receptor NR2B/cyclic adenosine monophosphate-response element binding protein signaling axis.

关键词： brain-derived neurotrophic factor late-onset Alzheimer’s disease N-methyl-D-aspartate receptor sortilin-related receptor 1 synapse

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 wearability.However,their relatively low sensitivity,linearity,and stability have hindered their large-scale commercial application.Herein,aﬂexible capacitive pressure sensor based on an interdigital electrode structure with two porous microneedle arrays(MNAs)is pro-posed.The porous substrate that constitutes the MNA is a mixed product of polydimethylsiloxane and NaHCO3.Due 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 structure.Finite-element analysis showed that the interdigital MNA structure can greatly increase the strain and improve the sensitivity of the sen-sor.In 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 structure.Most importantly,it was found that the sensor could accurately monitor the motion of aﬁnger,wrist joint,arm,face,abdomen,eye,and Adam’s apple.Furthermore,preliminary semantic recognition was achieved by monitoring the movement of the Adam’s apple.Finally,multiple pressure sensors were integrated into a 33 array to detect a spatial pressure distribu-×tion.Compared 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