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Interaction between ozone and paternal smoking on fetal congenital heart defects among pregnant women at high risk a multicenter maternal-fetal medicine study

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World Journal of Pediatrics 2024年第6期20卷 621-632页

作者： Huan wang Yan-Ping Ruan Sheng ma Ya-Qi wang Xiao-Yu wan Yi-Hua He Jing li Zhi-Yong Zou Institute of Child and Adolescent Health School of Public HealthNational Health Commission Key Laboratory of Reproductive HealthPeking UniversityNo.38 Xueyuan RdHaidian DistrictBeijing 100191China Echocardiography Medical Center Beijing Anzhen Hospital.Capital Medical UniversityMaternal-Fetal Medicine center in Fetal Heart DiseaseBeijing Anzhen HospitalNo.2 Anzhen RdChaoyang DistrictBeijing 100029China

Background Evidence remains limited on the association between maternal ozone(O,)exposure and congenital heart defects(CHDs)in offspring,and few studies have investigated the interaction and modification of paternal smoking on this *** Using a sample including pregnant women at high risk of fetal CHD(with metabolic disease,first-trimester viral infection,family history of CHD,etc.)from a maternal-fetal medicine study covering 1313 referral hospitals in China during 2013-2021,we examined the associations between maternal O_(3)exposure during 3-8 weeks of gestational age and fetal CHD in offspring and investigated the interaction and modification of paternal smoking on this *** was diagnosed by fetal echocardiograms,maximum daily 8-hour average O,exposure data at a 10 km×10 km spatial resolution came from the Tracking Air Pollution in China dataset,and paternal smoking was collected using *** regression models were used to estimate adjusted odds ratios(ORs)and 95%confidence intervals(CIs).Results Among 27,834 pregnant women at high risk of fetal CHD,17.4%of fetuses were diagnosed with *** 10μg/m^(3)increase in maternal O_(3)exposure was associated with a 17%increased risk of CHD in offspring(OR=1.17,95%CI=1.14-1.20).Compared with paternal nonsmoking and maternal low O_(3)exposure,the ORs(95%CI)of CHD for smoking and low O_(3)exposure,nonsmoking and high O_(3)exposure,and smoking and high O_(3)exposure were 1.25(1.08-1.45),1.81(1.56-2.08),and 2.23(1.84-2.71),*** smoking cessation seemingly mitigated the increased risk of *** maternal O_(3)exposure and paternal smoking were interactively associated with an increased risk of fetal CHD in offspring,which calls for effective measures to decrease maternal exposure to O_(3)pollution and secondhand smoke for CHDprevention.

关键词： Congenital heart defects Fetal heart development Ozone exposure Tobacco smoking

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Access to High-Molecular-Weight Polyethylenes through High Temperature Ethylene Polymerization Catalysed by Ethylene-Bridged ansa-(3-R-Cyclopentadienyl)(Fluorenyl) Zirconocene Complexes

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Chinese Journal of Polymer Science 2024年第1期42卷 42-51,I0007页

作者： Bo li Haiyan ma Jiling Huang Shanghai Key Laboratory of Functional materials Chemistry and Laboratory of Organometallic Chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

A series of C1-symmetric ethylene-bridged ansa-(3-R-cyclopentadienyl)(fluorenyl) metallocene complexes(Zr: 1-5;Hf: 6) have been synthesized, characterized and investigated as catalyst precursors for the high temperature ethylene polymerization. Using methylaluminoxane(maO) as the cocatalyst, zirconium complexes 1-5 bearing a bulky substituent on the 3-position of the cyclopendienyl ring showed high catalytic activities up to 1.48×10^(7) g PE·mol_(Zr)^(-1)·h^(-1) toward the polymerization of ethylene and afforded polyethylenes with high molecular weights(1.49×10^(5)-6.31×10^(5) g/mol), meanwhile exhibting great thermal stability at high temperatures up to 120 ℃ together with a long catalytic life time up to 2 h. By adopting low Al/Zr ratios, such as 125, polyethylenes with ultra high molecular weights up to 2.86×106 g/mol were obtained. It is worthy of noting that zirconium complexes 1-4 bearing a substituent with an aryl pendant showed temperature-dependent activities, which increased rapidly with the increase of polymerization temperature, thus weak interaction of the pendent aryl group with the cationic active center is proposed to account for the very low activities displayed at low temperatures. In contrast to zirconocene complexes 1-5, hafnocene complex 6 only displayed very low catalytic activities toward the polymerization of ethylene and afforded polyethylenes with molecular weights ten times smaller than those obtained by zirconocene complexes 1-5. Zirconocene complexes 1-5 were also able to catalyse the polymerization of propylene at high temperatures, but only afforded waxes with low molecular weights.

关键词： ansa-Metallocene Ethylene Propylene Polymerization High temperature

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Measuring Financial Systemic Risk:Net liability Clearing Mechanism and Contagion Effect

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Journal of Systems Science & Complexity 2024年第3期37卷 1114-1146页

作者： ma Jiali ZHU Shushang li Duan College of Big Data Statistics Guizhou University of Finance and EconomicsGuiyang 550025China School of Business Sun Yat-Sen UniversityGuangzhou 510275China School of Data Science City University of Hong KongHong Kong 999077China

Following the framework of E-N model(Eisenberg and Noe,2001),the authors consider a new clearing mechanism based on net liabilities among financial institutions since the liabilities between the counterparties should be deducted accordingly when clearing in *** the basis for systemic risk measurement,similar to the original E-N model,the authors first establish some good properties for the clearing payment vector according to a more general ***,the authors investigate how risk spreads among institutions through the liability network forming the risk contagion ***,the authors illustrate with a specific example that the original E-N clearing mechanism may misidentify the systemic important institutions,and theoretically show that it may also overestimate the risk compared with the netting clearing mechanism.

关键词： Clearing mechanism contagion net liability network systemic risk

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Development of EPDM composites reinforced by CNTs@SiO_(2)for thermal protection systems of aerospace propulsion:Significant improvement in oxidation and ablation resistance properties

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Chinese Journal of Aeronautics 2024年第2期37卷 471-481页

作者： li wanG Jiang li Kang li Yiwei wanG Chenyang ma Science and Technology on Combustion Internal Flow and Thermal-Structure LaboratoryNorthwestern Polytechnical UniversityXi’an 710072China

Carbon Nanotubes(CNTs)reinforced Polymer-matrix Composites(PMCs)is widely used as insulation materials in thermal protection system of aerospace ***,CNTs are prone to oxidation and have high thermal conductivities,which makes it difficult to improve the ablation resistance of insulation materials that contain ***_(2)was encapsulated onto the surface of CNTs(CNTs@SiO_(2)),which were then added to Ethylene Propylene Diene Monomer(EPDM)rubber to prepare the insulation *** analysis and ablation test were used to evaluate the resistance of the insulation materials to thermal oxidation and ***,scanning electron microscopy was performed to analyze their *** revealed that the addition of CNTs@SiO_(2)could visibly reduce the effects of hot corrosion and ablation on insulation *** C-CNTs@SiO_(2)-1 formulation had the best ablative ***,compared with the unencapsulated formulation(C-CNTs-10),the C-CNTs@SiO_(2)-1 formulation reduced the line ablation rate by 51%to 0.0130 mm/s after oxygen-acetylene ***,the ablation mechanism was investigated based on the effects of the CNTs@SiO_(2)additive on their ***,the improvement in ablation performance may be attributed to CNTs@SiO_(2)-induced decreases in thermal conductivity,improvement in the hot corrosion resistance in the char layer,and changes in the microstructure.

关键词： Polymer-matrix Composites(PMCs) Carbon Nanotubes(CNTs) Thermal properties Ablation Oxidation

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Semantic Consistency and Correctness Verification of Digital Traffic Rules

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Engineering 2024年第2期33卷 47-62页

作者： Lei wan Changjun wang Daxin Luo Hang liu Sha ma Weichao Hu Policy Standardand Patent DepartmentIntelligent Automotive Solution BUHuawei Technologies Co.Ltd.Beijing 100094China Research Institute for Road Safety of the Ministry of Public Security Beijing 100062China

The consensus of the automotive industry and traffic management authorities is that autonomous vehicles must follow the same traffic laws as human *** formal or digital methods,natural language traffic rules can be translated into machine language and used by autonomous *** this paper,a translation flow is *** the translation,a deeper examination is required,because the semantics of natural languages are rich and complex,and frequently contain hidden *** issue of how to ensure that digital rules are accurate and consistent with the original intent of the traffic rules they represent is both significant and *** response,we propose a method of formal verification that combines equivalence verification with model *** and reassuring digital traffic rules can be obtained by utilizing the proposed traffic rule digitization flow and verification *** addition,we offer a number of simulation applications that employ digital traffic rules to assess vehicle *** experimental findings indicate that our digital rules utilizing metric temporal logic(MTL)can be easily incorporated into simulation platforms and autonomous driving systems(ADS).

关键词： Autonomous driving Traffic rules Digitization Formalization Verification

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An empirical method for joint inversion of wave and wind parameters based on SAR and wave spectrometer data

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Acta Oceanologica Sinica 2024年第5期43卷 133-144页

作者： Yong wan Xiaona Zhang Shuyan Lang Ennan ma Yongshou Dai College of Oceanography and Space Informatics China University of PetroleumQingdao 266580China National Satellite marine Application Center Beijing 100081China Key Laboratory of Space Ocean Remote Sensing and Application Ministry of Natural ResourcesBeijing 100081China College of Control Science and Engineering China University of PetroleumQingdao 266580China

Synthetic aperture radar(SAR)and wave spectrometers,crucial in microwave remote sensing,play an essential role in monitoring sea surface wind and wave ***,they face inherent limitations in observing sea surface *** systems,for instance,are hindered by an azimuth cut-off phenomenon in sea surface wind field *** spectrometers,while unaffected by the azimuth cutoff phenomenon,struggle with low azimuth resolution,impacting the capture of detailed wave and wind field *** study utilizes SAR and surface wave investigation and monitoring(SWIM)data to initially extract key feature parameters,which are then prioritized using the extreme gradient boosting(XGBoost)*** research further addresses feature collinearity through a combined analysis of feature importance and correlation,leading to the development of an inversion model for wave and wind parameters based on XGBoost.A comparative analysis of this model with ERA5 reanalysis and buoy data for of significant wave height,mean wave period,wind direction,and wind speed reveals root mean square errors of 0.212 m,0.525 s,27.446°,and 1.092 m/s,compared to 0.314 m,0.888 s,27.698°,and 1.315 m/s from buoy data,*** results demonstrate the model’s effective retrieval of wave and wind ***,the model,incorporating altimeter and scatterometer data,is evaluated against SAR/SWIM single and dual payload inversion methods across different wind *** comparison highlights the model’s superior inversion accuracy over other methods.

关键词： synthetic aperture radar(SAR) wave spectrometer extreme gradient boosting(XGBoost) joint inversion method wave and wind parameters

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A Parameter Adaptive Method for Image Smoothing

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Tsinghua Science and Technology 2024年第4期29卷 1138-1151页

作者： Suwei wang Xiang ma Xuemei li School of Computer Science and Technology Shandong UniversityJinan 250101China School of Software Shandong UniversityJinan 250101China

Edge is the key information in the process of image smoothing. Some edges, especially the weak edges, are difficult to maintain, which result in the local area being over-smoothed. For the protection of weak edges, we propose an image smoothing algorithm based on global sparse structure and parameter adaptation. The algorithm decomposes the image into high frequency and low frequency part based on global sparse structure. The low frequency part contains less texture information which is relatively easy to smoothen. The high frequency part is more sensitive to edge information so it is more suitable for the selection of smoothing parameters. To reduce the computational complexity and improve the effect, we propose a bicubic polynomial fitting method to fit all the sample values into a surface. Finally, we use Alternating Direction Method of Multipliers (ADMM) to unify the whole algorithm and obtain the smoothed results by iterative optimization. Compared with traditional methods and deep learning methods, as well as the application tasks of edge extraction, image abstraction, pseudo-boundary removal, and image enhancement, it shows that our algorithm can preserve the local weak edge of the image more effectively, and the visual effect of smoothed results is better.

关键词： image smoothing parameter adaptation bicubic interpolation polynomial fitting

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Future Changes in Various Cold Surges over China in CMIP6 Projections

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Advances in Atmospheric Sciences 2024年第9期41卷 1751-1768页

作者： li ma Zhigang WEI Xianru li Shuting WU Key Laboratory of Environmental Change and Natural Disasters of Chinese Ministry of Education Beijing Normal UniversityBeijing 100875China State Key Laboratory of Earth Surface Processes and Resource Ecology(ESPRE) Beijing Normal UniversityBeijing 100875China Academy of Disaster Reduction and Emergency management Ministry of Emergency Management and Ministry of EducationBeijing 100875China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China

Cold surges(CSs)often occur in the mid-latitude regions of the Northern Hemisphere and have enormous effects on socioeconomic *** report that the occurrences of CSs and persistent CSs(PCSs)have rebounded since the 1990s,but the trends related to the frequencies of strong CSs(SCSs)and extreme CSs(ECSs)changed from increasing to decreasing after *** highest-ranked model ensemble approach was used to project the occurrences of various CSs under the SSP1-2.6,SSP2-4.5,and SSP5-8.5 *** frequencies of the total CSs show overall decreasing ***,under the SSP1-2.6 scenario,slight increasing trends are noted for SCSs and ECSs in *** circulations that are characterized by an anomalous anticyclonic circulation with a significantly positive 500-hPa geopotential height(Z500)anomaly at high latitudes along with significant negative anomalies in China were favorable for cold air intrusions into *** addition,the frequencies of all CS types under the SPP5-8.5 scenario greatly decreased in the long term(2071-2100),a finding which is thought to be related to negative SST anomalies in the central and western North Pacific,differences in sea level pressure(SLP)between high-and mid-latitude regions,and a weaker East Asian *** terms of ECSs,the decreasing trends observed during the historical period were maintained until 2024 under the SSP1-2.6 *** to the SSP1-2.6 scenario,the Z500 pattern showed a trend of strengthened ridges over the Ural region and northern East Asia and weakened troughs over Siberia(60°-90°E)under the SSP2-4.5 and SSP5-8.5 scenarios,contributing to the shift to increasing trends of ECSs after 2014.

关键词： cold surge “highest-ranked”model ensemble anticyclonic circulation geopotential height China

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Spatial Heterogeneity of Embedded Water Consumption from the Perspective of Virtual Water Surplus and Deficit in the Yellow River Basin,China

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Chinese Geographical Science 2024年第2期34卷 311-326页

作者： ma Weijing li Xiangjie KOU Jingwen li Chengyi College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China School of Economics and management Ningxia UniversityYinchuan 750021China

Virtual water trade(VWT)provides a new perspective for alleviating water crisis and has thus attracted widespread ***,the heterogeneity of virtual water trade inside and outside the river basin and its influencing factors remains further *** this study,for better investigating the pattern and heterogeneity of virtual water trade inside and outside provincial regions along the Yellow River Basin in 2015 using the input-output model(MRIO),we proposed two new concepts,i.e.,virtual water surplus and virtual water deficit,and then used the Logarithmic Mean Divisia Index(LMDI)model to identify the inherent mechanism of the imbalance of virtual water trade between provincial regions along the Yellow River Basin and the other four regions in *** results show that:1)in provincial regions along the Yellow River Basin,the less developed the economy was,the larger the contribution of the agricultural sector in virtual water trade,while the smaller the contribution of the industrial sector.2)Due to the large output of agricultural products,the upstream and midstream provincial regions of the Yellow River Basin had a virtual water surplus,with a net outflow of virtual water of 2.7×10^(8) m^(3) and 0.9×10^(8) m^(3),respectively.3)provincial regions along the Yellow River Basin were in a virtual water deficit with the rest of China,and the decisive factor was the active degree of trade with the *** study would be beneficial to illuminate the trade-related water use issues in provincial regions along the Yellow River Basin,which has farreaching practical signific-ance for alleviating water scarcity.

关键词： virtual water trade(VWT) input-output model(MRIO) virtual water surplus virtual water deficit Yellow River Basin,China

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Proactive Caching at the Wireless Edge:A Novel Predictive User Popularity-Aware Approach

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1997-2017页

作者： Yunye wan Peng Chen Yunni Xia Yong ma Dongge Zhu Xu wang Hui liu Weiling li Xianhua Niu Lei Xu Yumin Dong College of Computer Science Chongqing UniversityChongqing400044China School of Computer and Software Engineering Xihua UniversityChengdu610039China School of Computer and Information Engineering Jiangxi Normal UniversityNanchang330022China Electric Power Research Institute of State Grid Ningxia Electric Power Co. Ltd.Yinchuan750002China College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing400030China School of Computer Science and Technology Beijing Institute of TechnologyBeijing100083China School of Computer Science and Technology Dongguan University of TechnologyDongguan523808China School of Emergency management Xihua UniversityChengdu610039China College of Computer and Information Science Chongqing Normal UniversityChongqing401331China

Mobile Edge Computing(MEC)is a promising technology that provides on-demand computing and efficient storage services as close to end users as *** an MEC environment,servers are deployed closer to mobile terminals to exploit storage infrastructure,improve content delivery efficiency,and enhance user ***,due to the limited capacity of edge servers,it remains a significant challenge to meet the changing,time-varying,and customized needs for highly diversified content of ***,techniques for caching content at the edge are becoming popular for addressing the above *** is capable of filling the communication gap between the users and content providers while relieving pressure on remote cloud ***,existing static caching strategies are still inefficient in handling the dynamics of the time-varying popularity of content and meeting users’demands for highly diversified entity *** address this challenge,we introduce a novel method for content caching over MEC,i.e.,*** synthesizes a content popularity prediction model,which takes users’stay time and their request traces as inputs,and a deep reinforcement learning model for yielding dynamic caching *** results demonstrate that PRIME,when tested upon the MovieLens 1M dataset for user request patterns and the Shanghai Telecom dataset for user mobility,outperforms its peers in terms of cache hit rates,transmission latency,and system cost.

关键词： Mobile edge computing content caching system average cost deep reinforcement learning collaborative mechanism

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