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Insight study of rare earth elements in PM_(2.5)during five years in a Chinese inland city:Composition

Journal of Environmental Sciences 2024年第4期138卷 439-449页

作者： Yi-Wen Shen Chang-Xian Zhao Hao Zhao shuo-fei dong Qi Guo Jiao-Jiao Xie Mei-Ling Lv Chun-Gang Yuan Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department ofEnvironmental Science&EngineeringNorth China Electric Power UniversityBaoding 071000China MOE Key Laboratory of Resources and Environmental Systems Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China Agilent Technologies Co.Ltd.(China) Beijing 100102China

The booming development of rare earth industry and the extensive utilization of its products accompanied by urban development have led to the accelerated accumulation of rare earth elements(REEs)as emerging pollutants in atmospheric environment.In this study,the variation of REEs in PM_(2.5)with urban(a non-mining city)transformation was investigated through five consecutive years of sample collection.The compositional variability and provenance contribution of REEs in PM_(2.5)were characterized,and the REEs exposure risks of children and adults via inhalation,ingestion and dermal absorption were also evaluated.The results showed an increase in the total REEs concentration from 46.46±35.16 mg/kg(2017)to 81.22±38.98 mg/kg(2021)over the five-year period,with Ce and La making the largest contribution.The actual increment of industrial and traffic emission source among the three pollution sources was 1.34 ng/m^(3).Coal combustion source displayed a downward trend.Ingestion was the main exposure pathway for REEs in PM_(2.5)for both children and adults.Ce contributed the most to the total intake of REEs in PM_(2.5)among the population,followed by La and Nd.The exposure risks of REEs in PM_(2.5)in the region were relatively low,but the trend of change was of great concern.It was strongly recommended to strengthen the concern about traffic-related non-exhaust emissions of particulate matter.

关键词： Rare earth elements Exposure risks Pollution sources Traffic-related non-exhaust emissions

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Aircraft Observation and Simulation of the Supercooled Liquid Water Layer in a Warm Conveyor Belt over North China

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Advances in Atmospheric Sciences 2024年第3期41卷 529-544页

作者： Jiefan YANG fei YAN Hengchi LEI shuo JIA Xiaobo dong Xiangfeng HU Key Laboratory of Cloud Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Weather modification office of Hebei Province Hebei Meteorology AdministrationShijiazhuang 050000China

This paper studied a snow event over North China on 21 February 2017,using aircraft in-situ data,a Lagrangian analysis tool,and WRF simulations with different microphysical schemes to investigate the supercooled layer of warm conveyor belts(WCBs).Based on the aircraft data,we found a fine vertical structure within clouds in the WCB and highlighted a 1-2 km thin supercooled liquid water layer with a maximum Liquid Water Content(LWC) exceeding0.5 g kg^(-1) during the vertical aircraft observation.Although the main features of thermodynamic profiles were essentially captured by both modeling schemes,the microphysical quantities exhibited large diversity with different microphysics schemes.The conventional Morrison two-moment scheme showed remarkable agreement with in-situ observations,both in terms of the thermodynamic structure and the supercooled liquid water layer.However,the microphysical structure of the WCB clouds,in terms of LWC and IWC,was not apparent in HUJI fast bin scheme.To reduce such uncertainty,future work may focus on improving the representation of microphysics in bin schemes with in-situ data and using similar assumptions for all schemes to isolate the impact of physics.

关键词： warm conveyor belt Microphysical properties supercooled liquid water microphysics schemes

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Polysaccharides from Chinese herbal medicine:a review on the hepatoprotective and molecular mechanism

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Chinese Journal of Natural Medicines 2024年第1期22卷 4-14页

作者： LI Jifeng GUO Haolin dong Ying YUAN shuo WEI Xiaotong ZHANG Yuxin dong Lu WANG fei BAI Ting YANG Yong Dalian Key Laboratory of Chronic Disease Research Center Dalian UniversityDalian 116622China Key Laboratory of Natural Medicines of the Changbai Mountain Ministry of EducationCollege of PharmacyYanbian UniversityYanji 133002China

Polysaccharides,predominantly extracted from traditional Chinese medicinal herbs such as Lycium barbarum,Angelica sinensis,Astragalus membranaceus,Dendrobium officinale,Ganoderma lucidum,and Poria cocos,represent principal bioactive constituents extensively utilized in Chinese medicine.These compounds have demonstrated significant anti-inflammatory capabilities,especially anti-liver injury activities,while exhibiting minimal adverse effects.This review summarized recent studies to elucidate the hepatoprotective efficacy and underlying molecular mechanisms of these herbal polysaccharides.It underscored the role of these polysaccharides in regulating hepatic function,enhancing immunological responses,and improving antioxidant capacities,thus contributing to the attenuation of hepatocyte apoptosis and liver protection.Analyses of molecular pathways in these studies revealed the intricate and indispensable functions of traditional Chinese herbal polysaccharides in liver injury management.Therefore,this review provides a thorough examination of the hepatoprotective attributes and molecular mechanisms of these medicinal polysaccharides,thereby offering valuable insights for the advancement of polysaccharide-based therapeutic research and their potential clinical applications in liver disease treatment.

关键词： Polysaccharides Hepatoprotective Chinese herbal medicine Mechanism

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Fusion of Spiral Convolution-LSTM for Intrusion Detection Modeling

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Computers, Materials & Continua 2024年第5期79卷 2315-2329页

作者： fei Wang Zhen dong School of Cyberspace Security Gansu University of Political Science and LawLanzhou73000China

Aiming at the problems of low accuracy and slow convergence speed of current intrusion detection models,SpiralConvolution is combined with Long Short-Term Memory Network to construct a new intrusion detection model.The dataset is first preprocessed using solo thermal encoding and normalization functions.Then the spiral convolution-Long Short-Term Memory Network model is constructed,which consists of spiral convolution,a two-layer long short-term memory network,and a classifier.It is shown through experiments that the model is characterized by high accuracy,small model computation,and fast convergence speed relative to previous deep learning models.The model uses a new neural network to achieve fast and accurate network traffic intrusion detection.The model in this paper achieves 0.9706 and 0.8432 accuracy rates on the NSL-KDD dataset and the UNSWNB-15 dataset under five classifications and ten classes,respectively.

关键词： Intrusion detection deep learning spiral convolution long and short term memory networks 1D-spiral convolution

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Active disturbance rejection distributed secondary control for DC microgrids

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High Voltage 2024年第1期9卷 241-251页

作者： Jianlin Li Honghao You shuo Liu Xingchen Li Ziyang Ding fei Zou National User-Side Energy Storage Innovation Research and Development Center North China University of TechnologyBeijingChina

A novel control scheme is presented to eliminate the negative effects of communication disturbances,which introduces active disturbance rejection control(ADRC)in the control strategy design to achieve the objectives of the restoration of the bus voltage and the sharing of the power even in the presence of disturbances and delays in communication.Simultaneously,its dynamic disturbance decoupling feature is used to realise the decoupling between power and voltage,so that the proposed controller only exchanges power information with its neighbours,reducing the communication burden and simplifying control structure.The control performance of the strategy is verified by employing steady-state analysis.The impact of controller parameters is studied by establishing a small signal model.Finally,both simulation cases and experimental tests prove the feasibility of this scheme.

关键词： Active disturbance establishing

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Developing a diagnostic model for predicting prostate cancer: a retrospective study based on Chinese multicenter clinical data

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Asian Journal of Andrology 2024年第1期26卷 34-40页

作者： Chang-Ming Wang Lei Yuan Xue-Han Liu Shu-Qiu Chen Hai-Feng Wang Qi-fei dong Bin Zhang Ming-shuo Huang Zhi-Yong Zhang Jun Xiao Tao Tao Department of Urology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Department of Radiology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Core Facility Center for Medical Sciences The First Affiliated Hospital of USTcDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Department of Urology Affiliated Zhongda Hospital of Southeast UniversityNanjing 210009China Department of Urology Shanghai East HospitalTongji University School of MedicineShanghai 200120China Department of Urology Shanghai Changhai HospitalSecond Military Medical UniversityShanghai 200000China Department of Urology Affiliated Anhui Provincial Hospital of Anhui Medical UniversityHefei 230001China

The overdiagnosis of prostate cancer(PCa)caused by nonspecific elevation serum prostate-specific antigen(PSA)and the overtreatment of indolent PCa have become a global problem that needs to be solved urgently.We aimed to construct a prediction model and provide a risk stratification system to reduce unnecessary biopsies.In this retrospective study,clinical data of 1807 patients from three Chinese hospitals were used.The final model was built using stepwise logistic regression analysis.The apparent performance of the model was assessed by receiver operating characteristic curves,calibration plots,and decision curve analysis.Finally,a risk stratification system of clinically significant prostate cancer(csPCa)was created,and diagnosis-free survival analyses were performed.Following multivariable screening and evaluation of the diagnostic performances,a final diagnostic model comprised of the PSA density and Prostate Imaging-Reporting and Data System(PI-RADS)score was established.Model validation in the development cohort and two external cohorts showed excellent discrimination and calibration.Finally,we created a risk stratification system using risk thresholds of 0.05 and 0.60 as the cut-off values.The follow-up results indicated that the diagnosis-free survival rate for csPCa at 12 months and 24 months postoperatively was 99.7%and 99.4%,respectively,for patients with a risk threshold below O.05 after the initial negative prostate biopsy,which was significantly better than patients with higher risk.Our diagnostic model and risk stratification system can achieve a personalized risk calculation of csPCa.It provides a standardized tool for Chinese patients and physicians when considering thenecessity of prostatebiopsy.

关键词： nomogram prostate biopsy prostate cancer Prostate Imaging-Reporting and Data System prostate-specific antigen density

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Parallelization strategies for resolved simulations of fluid-structure-particle interactions

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 857-872页

作者： Jianhua QIN fei LIAO Guodan dong Xiaolei YANG The State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China Interdisciplinary Center for Fundamental and Frontier Sciences Nanjing University of Science and TechnologyJiangyin 214443Jiangsu ProvinceChina School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China

Fluid-structure-particle interactions in three spatial dimensions happen in many environmental and engineering flows.This paper presents the parallel algorithms for the hybrid diffuse and sharp interface immersed boundary(IB)method developed in our previous work.For the moving structure modeled using the sharp interface IB method,a recursive box method is developed for efficiently classifying the background grid nodes.For the particles modeled using the diffuse interface IB method,a‘master-slave’approach is adopted.For the particle-particle interaction(PPI)and particle-structure interaction(PSI),a fast algorithm for classifying the active and inactive Lagrangian points,which discretize the particle surface,is developed for the‘dry’contact approach.The results show that the proposed recursive box method can reduce the classifying time from 52seconds to 0.3 seconds.Acceptable parallel efficiency is obtained for cases with different particle concentrations.Furthermore,the lubrication model is utilized when a particle approaches a wall,enabling an accurate simulation of the rebounding phenomena in the benchmark particle-wall collision problem.At last,the capability of the proposed computational framework is demonstrated by simulating particle-laden turbulent channel flows with rough walls.

关键词： particle-resolved direct numerical simulation particle-laden flow complex geometry resolved fluid-structure-particle interaction(RFSPI) immersed boundary(IB)method

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Nuclearity and Finite-Representability in the System of Completely Integral Mapping Spaces

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1197-1214页

作者： Zhe dong Ji Cheng TAO Ya fei ZHAO Department of Mathematics Zhejiang UniversityHangzhou 310027P.R.China Department of Mathematics China Jiliang UniversityHangzhou 310018P.R.China Department of Mathematics Zhejiang International Studies UniversityHangzhou 310023P.R.China

In this paper,we investigate local properties in the system of completely integral mapping spaces.We introduce notions of injectivity,local reflexivity,exactness,nuclearity,finite-represent ability and WEP in the system of completely integral mapping spaces.First we obtain that any finite-dimensional operator space is injective in the system of completely integral mapping spaces.Furthermore we prove that C is the unique nuclear operator space and the unique exact operator space in this system.We also show that C is the unique operator space which is finitely representable in{T_(n)}n∈Nin this system.As corollaries,Kirchberg’s conjecture and QWEP conjecture in the system of completely integral mapping spaces are false.

关键词： Completely integral mapping space injectivity exactness nuclearity finite-representability WEP

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Strengthening mechanism and forming control of linear friction welded GH4169 alloy joints

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Chinese Journal of Aeronautics 2024年第4期37卷 609-626页

作者： Yu SU Xiawei YANG Tingxi MENG Xinyuan HE dong WU Wenya LI shuo YIN State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of Friction Welding Technologies School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Mechanical Manufacturing and Biomedical EngineeringParsons BuildingTrinity College DublinThe University of DublinDublin 2Ireland

Numerical simulation and experimental research on Linear Friction Welding(LFW) for GH4169 superalloy were carried out. Based on the joint microstructure and mechanical properties,a suitable welding process was determined, which provided an important theoretical basis for the manufacture and repair of aeroengine components such as the superalloy blisk. The results show that the joint strain rate gradually increases with the increase of welding frequency, and the deformation resistance of the thermoplastic metal increases in the welding process, resulting in the interface thermoplastic metal not being extruded in time to form a flash, so the joint shortening amount gradually decreases. The thermoplastic metal in the center of the welding surface is kept at high welding temperature for a long time, resulting in the decrease of the joint strength. The microhardness of the joint shows a “W” distribution perpendicular to the weld, and most of the joints break in the Thermo-Mechanically Affected Zone(TMAZ) with high tensile strength and low elongation.When the welding area is increased without changing the aspect ratio of the welding surface, the interface peak temperature increases gradually, and the joint shortening amount decreases with the increase of the welding interface size.

关键词： Linear Friction Welding(LFW) Microstructure Mechanical properties Numerical simulation Joint shortening amount

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Should we perform sigmoidoscopy for colorectal cancer screening in people under 45 years?

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1248-1255页

作者： Waiian Leong Jia-Qi Guo Chun Ning fei-fei Luo Rui Jiao dong-Ye Yang Division of Gastroenterology&Hepatology The University of Hong Kong-Shenzhen HospitalShenzhen 518053Guangdong ProvinceChina Department of Accident&Emergency The University of Hong Kong-Shenzhen HospitalShenzhen 518053Guangdong ProvinceChina Department of Anatomical Pathology The University of Hong Kong-Shenzhen HospitalShenzhen 518053Guangdong ProvinceChina Endoscopy Center The University of Hong Kong-Shenzhen HospitalShenzhen 518053Guangdong ProvinceChin

BACKGROUND The strategy for preventing colorectal cancer is screening by colonoscopy,which offers a direct way for detection and removal of adenomatous polyps(APs).American College of Gastroenterology guidelines recommend that people aged≥45 years should undergo colonoscopy;however,how to deal with people aged≤45 years is still unknown.AIM To compare the prevalence of APs and high-grade neoplasia between the left and right colon in patients≤45 years.METHODS A retrospective observational study was conducted at a single tertiary III hospital in China.This study included patients aged 18-45 years with undergoing initial colonoscopy dissection and pathological diagnosis AP or high-grade neoplasia between February 2014 and January 2021.The number of APs in the entire colon while screening and post-polypectomy surveillance in following 1-3 years were evaluated.RESULTS A total of 3053 cases were included.The prevalence of APs in the left and right colon was 55.0%and 41.6%,respectively(OR 1.7,95%CI 1.6-2.4;P3 polyps(14.1%;OR 0.3,95%CI 0.1-0.6;P<0.05).CONCLUSION This study suggests that flexible sigmoidoscopy would be an optimal approach for initial screening in people aged≤45 years and would be a more cost-effective and safe strategy.

关键词： Adenomatous polyps High-grade neoplasia Colonoscopy Flexible sigmoidoscopy

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