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Associations of Gestational Exposure to Air Pollution and Polycyclic Aromatic Hydrocarbons with Placental Inflammation

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Environment & health 2024年第9期2卷 672-680页

作者： Emily A.Craig Yan Lin Yihui Ge Xiangtian Wang Susan K.murphy Donald K.Harrington Richard K.miller Sally W.Thurston Philip K.Hopke Emily S.Barrett Thomas G.O’Connor David q.Rich Junfeng Zhang Nicholas School of the Environment&Duke Global health Institute Duke UniversityDurhamNorth Carolina 27708United States Department of Psychiatry University of Rochester School of Medicine and DentistryRochesterNew York 14642United States Department of Obstetrics and Gynecology University of Rochester School of Medicine and DentistryRochesterNew York 14642United States Department of Environmental medicine and Department of Pediatrics University of Rochester School of Medicine and DentistryRochesterNew York 14642United States Department of Psychology University of RochesterRochesterNew York 14642United States Department of Biostatistics and Computational Biology and Department of Environmental medicine University of Rochester School of Medicine and DentistryRochesterNew York 14642United States Department of Public health Sciences University of Rochester School of Medicine and DentistryRochesterNew York 14642United States Department of Biostatistics and Epidemiology Rutgers School of Public HealthPiscatawayNew Jersey 08854United States Department of Psychiatry and Department of Neuroscience University of Rochester School of Medicine and DentistryRochesterNew York 14642United States Department of Public health Sciences Department of Medicineand Department of Environmental MedicineUniversity of Rochester School of Medicine and DentistryRochesterNew York 14642United States

Restricted fetal growth(RFG)is a leading contributor to perinatal mortality and has been associated with gestational exposure to air pollution,such as fine particulate matter(Pm_(2.5)),nitrogen dioxide(NO2),and polycyclic aromatic hydrocarbons(PAHs).This study examines the association between trimester-specific and weekly means of air pollution throughout gestation and placental inflammatory markers at *** a prospective cohort study of 263 pregnant women in Rochester,NY,we measured interleukin-6(IL-6)and tumor necrosis factor-alpha(TNF-α)in placental tissue and estimated gestational exposure to Pm_(2.5)and NO_(2)using a high-resolution spatial-temporal *** to PAHs was estimated using urinary 1-hydroxypyrene(1-OHP)concentrations collected once per *** distributed lag models with a penalized spline function,each interquartile range(2.6μg/m^(3))increase in Pm_(2.5)concentration during gestational weeks 6−11 was associated with decreased placental IL-6 levels(−22.2%,95%CI:−39.0%,−0.64%).Using multiple linear regression models,each interquartile range increase of 1-OHP was associated with an increase in TNF-αin the first trimester(58.5%,95%CI:20.7%,74.2%),third trimester(22.9%,95%CI:0.04%,49.5%),and entire pregnancy(29.6%,95%CI:3.9%,60.6%).Our results suggest gestational exposure to air pollution may alter the inflammatory environment of the placenta at delivery.

关键词： pregnancy air pollution PAHs placenta tumor necrosis factor interleukin

Harmonic balance-based approach for optimal time delay to control unstable periodic orbits of chaotic systems

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Acta mechanica Sinica 2020年第4期36卷 918-925页

作者： Y.m.Chen q.X.Liu J.K.Liu Department of mechanics Sun Yat-sen UniversityGuangzhou 510275China

As a classical technique for chaos suppression,the time-delayed feedback controlling strategy has been widely developed by stabilizing unstable periodic orbits(UPOs)embedded in chaotic systems.A critical issue for achieving high controlling precision is to search for an appropriate time *** paper proposes a simple yet effective approach,based on incremental harmonic balance method,to determine the optimal time delay in the delayed feedback *** time delay is adjusted within the iterative scheme provided by the proposed method,and finally converges to the period of the target *** long as the optimal time delay is fixed,moreover,the attained solution makes it quite convenient to analyze its stability according to the Floquet theory,which further provides the effective interval of the feedback gain.

关键词： Chaos control Unstable periodic orbit Delayed feedback Optimal time delay Incremental harmonic balance method

Vibration characteristics of piezoelectric functionally graded carbon nanotube-reinforced composite doubly-curved shells

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Applied mathematics and mechanics(English Edition) 2021年第6期42卷 819-840页

作者： V.V.THAm H.q.TRANT T.m.TU National Univensity of Ciwil Engineering Giai Phong Road 55Hai Ba Trung DistrictHanoi 100000 Vietnam

This paper presents an analytical solution for the free vibration behavior of functionally graded carbon nanotube-reinforced composite(FG-CNTRC) doubly curved shallow shells with integrated piezoelectric layers. here, the linear distribution of electric potential across the thickness of the piezoelectric layer and five different types of carbon nanotube(CNT) distributions through the thickness direction are considered. Based on the four-variable shear deformation refined shell theory, governing equations are obtained by applying Hamilton's principle. Navier's solution for the shell panels with the simply supported boundary condition at all four edges is derived. Several numerical examples validate the accuracy of the presented solution. New parametric studies regarding the effects of different material properties, shell geometric parameters, and electrical boundary conditions on the free vibration responses of the hybrid panels are investigated and discussed in detail.

关键词： free vibration four-variable shear deformation refined theory functionally graded carbon nanotube-reinforced composite(FG-CNTRC) piezoelectric material

The role of melt cooling rate on the interface between 18R and mg matrix in mg_(97)Zn_(1)Y_(2) alloys

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Journal of magnesium and Alloys 2023年第8期11卷 2883-2890页

作者： q.q.Jin X.H.Shao J.m.Li Z.Z.Peng m.Lv B.Zhang Y.m.Li X.L.ma materials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of materials Science and Engineering Hebei University of Science and TechnologyShijiazhuangHebei 050018China

The role of melt cooling rate on the interface morphology and dislocation configuration between 18R long-period stacking ordered(LPSO)structure and mg matrix in mg_(97)Zn_(1)Y_(2)(at.%)alloys was investigated by atomic-scale HAADF-STEm *** 18R/mg interface is step-like both in the near-equilibrium alloy and non-equilibrium *** cooling rate makes the step size more regular and *** 54R structure can be observed at the interface in the near-equilibrium alloy,and the dislocations are highly ordered.54R and 54R′structure sandwiched by b1 and b2+b3 dislocation arrays,and new dislocation configuration can be detected at the interface in the non-equilibrium alloy,but the dislocations are less ordered.18R/mg interface containing 54R or 54R′in equilibrium width,parallel to the(010)plane,should be most stable based on elastic *** segregation of solute atoms and its strong interaction with dislocations dominate the LPSO/mg interface via diffusion-displacive transformation.

关键词： magnesium alloys Long-period stacking ordered phases Dislocations Interface structure

Study of K^(*)(892)^(0)andФ(1020)meson production in proton–proton and Pb–Pb collisions at√S_(NN)=2.76 TeV

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Communications in Theoretical Physics 2021年第2期73卷 89-95页

作者： Y Ali m Ahmed A Arif q Ali U Tabassam U Rubab m Suleymanov Department of Physics COMSATS UniversityPark RoadIslamabad44000Pakistan Institute for Physical Problems Baku Suate UniversityBakuAZ 1000Azrbajan

In this paper,we describe a study of charged particle yield as a function of pT for K^(*)(892)0 and phgr(1020)mesons in proton–proton(pp)and Pb–Pb collisions at√S_(NN)=2.76 TeV in the central rapidity region of|y|mportant ratio,the nuclear modification factor,to study the effects of the medium in the most central region,i.e.0%–5%*** data simulation,we used the EPOS-LHC and EPOS-1.99 *** check the validity of these models'simulations,we compared the data obtained from these monte Carlo simulation programs with ALICE experimental data for√S_(NN)=2.76 *** was concluded that the models'predictions for the phgr-meson in pp and for the most central Pb-Pb collisions disagreed with the ALICE data,and that the difference increased with *** may be connected with the essential role of collective parton behaviors which could not have been taken into account by the *** K^(*)0 mesons,both programs gave almost the same predictions,and with pT in the interval pT>3 GeV c^(−1),the predictions were very close to the experimental *** models gave higher predictions for the soft pT interval and lower predictions for the hard *** values of the RAA distributions were lower than unity and both models were very close to the ALICE *** is very interesting that the models were not able to describe the pT distributions,but they gave good predictions for their *** may possibly be due to parton collective *** observed some additional suppression of K^(*)0 at low values of pT with respect to phgr-mesons,which may be related to the role of the masses of the particles in soft *** rising trend for R_(AA)in the region from pT=10 GeV c^(−1)to 20 GeV c^(−1) observed by the ALICE experiment was absent for theФ-mesons.

关键词： quark Gluon Plasma EPOS-LHC nuclear modification factor

Group Generated by Two Elements of orders 2 and 4 Acting on Real quadratic Fields

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Acta mathematica Sinica,English Series 1993年第1期9卷 48-54页

作者： q.mushtaq m.Aslam Department of mathematics Quaid-i-Azam UniversityIslamabauPakistan

Coset diagrams for the orbit of the group G=acting on realquadratic fields give some interesting *** using these coset diagrams,we show thatin the orbit pG,where p=(a+n)/c,the non-square positive integer n does not change itsvalue and the real quadratic irrational numbers of the form p,where p and its algebraic conjugate(α-n)/c have different signs,are finite in number and that part of the coset diagram containingsuch numbers forms a single closed path,which is the only closed path in the orbit of p.

关键词： Group Generated by Two Elements of orders 2 and 4 Acting on Real quadratic Fields

Alloy design by dislocation engineering

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Journal of materials Science & Technology 2018年第3期34卷 417-420页

作者： m.X.Huang B.B.he Department of mechanical Engineering The University of Hong Kong

Ultra-high strength alloys with good ductility are ideal materials for lightweight structural application in various industries. However, improving the strength of alloys frequently results in a reduction in ductility, which is known as the strength-ductility trade-off in metallic materials. Current alloy design strategies for improving the ductility of ultra-high strength alloys mainly focus on the selection of alloy composition （atomic length scale） or manipulating ultra-fine and nano-grained microstructure （grain length scale）. The intermediate length scale between atomic and grain scales is the dislocation length scale. A new alloy design concept based on such dislocation length scale, namely dislocation engineering, is illustrated in the present work. This dislocation engineering concept has been successfully substantiated by the design and fabrication of a deformed and partitioned （D＆P） steel with a yield strength of 2,2 GPa and an uniform elongation of 16%. In this D＆P steel, high dislocation density can not only increase strength but also improve ductility. High dislocation density is mainly responsible for the improved yield strength through dislocation forest hardening, whilst the improved ductility is achieved by the glide of intensive mobile dislocations and well-controlled transformation-induced plasticity （TRIP） effect, both of which are governed by the high dislocation density resulting from warm rolling and martensitic transformation during cold rolling. In addition, the present work proposes for the first time to apply such dislocation engineering concept to the quenching and partitioning （q＆P） steel by incorporating a warm rolling process prior to the quenching step, with an aim to improve simultaneously the strength and ductility of the q＆P steel. It is believed that dislocation engineering provides a new promising alloy design strategy for producing novel strong and ductile alloys.

关键词： Alioy design Dislocation engineering D&P steel q&P steel TRIP Warm rolling

全球城市扩展模拟数据集(1992-2050)

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全球变化数据学报（中英文） 2024年第1期8卷 90-97,V0090-V0097页

作者：刘志锋应嘉禾何春阳黄庆旭白巧贤潘鑫豪北京师范大学地表过程与资源生态国家重点实验室北京100875 北京师范大学地理科学学部自然资源学院北京100875 北京师范大学环境演变与自然灾害教育部重点实验室北京100875 应急管理部-教育部减灾与应急管理研究院北京100875

全球城市扩展数据是开展全球城市扩展过程及其影响与优化研究的基础,但现有数据未有效区分城乡建设用地,导致相关研究结果存在较大不确定性。本文复合全球建设用地数据和全球城市中心位置数据重建了全球1992–2020年逐年城市扩展过程,... 详细信息

全球城市扩展数据是开展全球城市扩展过程及其影响与优化研究的基础,但现有数据未有效区分城乡建设用地,导致相关研究结果存在较大不确定性。本文复合全球建设用地数据和全球城市中心位置数据重建了全球1992–2020年逐年城市扩展过程,利用土地利用情景变化动力学-城市(Land Use Scenario Dynamics-urban,LUSD-urban)模型分区模拟了5种共享社会经济路径下全球2020–2050年城市扩展过程,构建了一套有效区分城乡建设用地且连续可比的全球城市扩展数据集。精度评价表明该数据集准确可靠,模型模拟结果的Kappa系数为0.88、Fom为0.23。本数据集包含1992–2020年逐年全球历史城市建成区范围和2021–2050年逐五年全球未来城市建成区范围,数据集的空间分辨率为1 km,存储格式为.tif。数据量为498 mB,压缩后为23.7 mB。

关键词：城市扩展全球 1992–2050年共享社会经济路径城市化

Improved Consensus Speed for Discrete-Time multi-agent Systems

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Journal of Donghua University(English Edition) 2013年第6期30卷 461-465页

作者： Li m. Li q.-q. Gao H.-L. School of Control Science and Engineering Shandong University Jinan 250061 China School of Electrical Engineering and Automation Qilu University of Technology Jinan 250061 China College of Automation South China University of Technology Guangzhou 510641 China

The consensus problem of a linear discrete-time multi- agent system with directed communication topologies was investigated. A protocol was designed to solve consensus with an improved convergence speed achieved by designing protocol gains. The clo6ed-loop *** system converged to an expected type of consensus function, which was divided into four types： zero, non- zero constant vector, bounded trajectories, and ramp trajectories. An algorithm was further provided to construct the protocol gains, which were determined in terms of a classical pole placement algorithm and a modified algebraic Riccati equation. Finally, an example to illustrate the effectiveness of theoretical results was presented.

关键词： discrete-time multi-agent consensus function consensus speed