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Characteristics of ozone vertical profile observed in the boundary layer around Beijing in autumn

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Journal of Environmental Sciences 2011年第8期23卷 1316-1324页

作者： Zhiqiang Ma Xiaoling Zhang Jing Xu xiujuan zhao Wei Meng Institute of Urban Meteorology China Meteorological Administration Beijing 100089 China.

In the autumn of 2008, the vertical profiles of ozone and meteorological parameters in the low troposphere （0-1000 m） were observed at two sites around Beijing, specifically urban Nanjiao and rural Shangdianzi. At night and early morning, the lower troposphere divided into two stratified layers due to temperature inversion. Ozone in the lower layer showed a large gradient due to the titration of NO. Air flow from the southwest brought ozone-rich air to Beijing, and the ozone profiles were marked by a continuous increase in the residual layer at night. The accumulated ozone in the upper layer played an important role in the next day＇s surface peak ozone concentration, and caused a rapid increase in surface ozone in the morning. Wind direction shear and wind speed shear exhibited different influences on ozone profiles and resulted in different surface ozone concentrations in Beijing.

关键词： ozonesonde ground-level ozone in Beijing wind shear

Revisiting influenza A virus life cycle from a perspective of genome balance

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Virologica Sinica 2023年第1期38卷 1-8页

作者： Ruikun Du Qinghua Cui Zinuo Chen xiujuan zhao Xiaojing Lin Lijun Rong Innovation Research Institute of Traditional Chinese Medicine Shandong University of Traditional Chinese MedicineJinan250355China Qingdao Academy of Chinese Medicinal Sciences Shandong University of Traditional Chinese MedicineQingdao266122China College of Pharmacy Shandong University of Traditional Chinese MedicineJinan250355China Department of Microbiology and Immunology College of MedicineUniversity of Illinois at ChicagoChicago60612USA

Influenza A virus(IAV)genome comprises eight negative-sense RNA segments,of which the replication is well orchestrated and the delicate balance of multiple segments are dynamically regulated throughout IAV life ***,previous studies seldom discuss these balances except for functional hemagglutinin-neuraminidase balance that is pivotal for both virus entry and ***,we attempt to revisit IAV life cycle by highlighting the critical role of“genome balance”.Moreover,we raise a“balance regression”model of IAV evolution that the virus evolves to rebalance its genome after reassortment or interspecies transmission,and direct a“balance compensation”strategy to rectify the“genome imbalance”as a result of artificial modifications during creation of recombinant *** review not only improves our understanding of IAV life cycle,but also facilitates both basic and applied research of IAV in future.

关键词： Influenza A virus(IAV) Segmented genome Genome balance Balance regression Balance compensation

Impact of emission reduction on aerosol-radiation interaction during heavy pollution periods over Beijing-Tianjin-Hebei region in China

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Journal of Environmental Sciences 2020年第9期32卷 2-13页

作者： Wei Wen Chunwei Guo Xin Ma xiujuan zhao Lei Liu Dan Chen Jing Xu Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China National Meteorological Center Beijing 100081China Key Laboratory of Atmospheric Chemistry China Meteorological AdministrationBeijing 100081China

In December 2015,the Beijing-Tianjin-Hebei(BTH) region experienced several episodes of heavy air *** government immediately issued emergency control measures to reduce the pollution,which provided a good opportunity to explore the impact of emission reduction on aerosol-radiation *** this study,four tests were conducted,including the basel simulation with emission reduction and aerosol-radiation interaction on,the base2 simulation with emission reduction and aerosol-radiation interaction off,the scenariol simulation without emission reduction and aerosol-radiation interaction on and the scenario2 simulation without emission reduction and aerosol-radiation interaction *** find that the aerosol-radiation interaction decreased the downward shortwave radiation and the temperature at 2 m,reduced the planetary boundary layer height(PBLH) in the region,and increased the relative humidity at 2 m,which is favorable for pollution *** results revealed that the interaction effect due to emission reductions increased downward shortwave radiation by an average of 0-5 W/m2,leading to increase in surface temperature of 0-0.05℃,increase in the daytime mean PBL high of 0-8 m,and decrease in daytime mean relative humidity at 2 m of 0.5%.We found that if there were aerosol-radiation interaction,it would enhance the effectiveness of emission control measures on air pollution *** enhance of PM2.5(particulate matter less than 2.5 um),PM10(particulate matter less than 10 um),and NO2(nitrogen dioxide) emission reduction effects reached7.62%,6.90%,11.62%,respectively,over this region.

关键词： pollution. pollution aerosol

MUTUAL ARTIFICIAL BEE COLONY ALGORITHM FOR MOLECULAR DOCKING

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International Journal of Biomathematics 2013年第6期6卷 17-27页

作者： RUIXIN MA xiujuan XU LEI zhao REN CAO QIANG FANG School of Software Dalian University of Technology Dalian 116620 P. R. China

Molecular docking method plays an important role on the quest of potential drug candidates, which has been proven to be a valuable tool for virtual screening. Molecular docking is commonly referred to as a parameter optimization problem. During the last decade, some optimization algorithms have been introduced, such as Lamarckian genetic algorithm （LGA） and SODOCK embedded in the AutoDock program. On the basis of the latest docking software AutoDock4.2, we present a novel docking program ABCDock, which incorporates mutual artificial bee colony （MutualABC） into AutoDock. Computer simulation results demonstrate that ABCDock takes precedence over AutoDock and SODOCK, in terms of convergence performance, accuracy, and the lowest energy, especially for highly flexible ligands. It is noteworthy that ARCDock yields a higher success rate. Also, in comparison with the other state-of-the-art docking methods, namely GOLD, DOCK and FlexX, ABCDock provides the smallest RMSD in 27 of 37 cases.

关键词： Artificial Bee Colony AutoDock molecular docking

Relationships Between Evacuation Population Size, Earthquake Emergency Shelter Capacity, and Evacuation Time

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International Journal of Disaster Risk Science 2017年第4期8卷 457-470页

作者： xiujuan zhao Wei Xu Yunjia Ma Lianije Qin Junlin Zhang Ying Wang State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical Science Beijing Normal University Key Laboratory of Environmental Change and Natural Disaster of Ministry of Education Beijing Normal University Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of Education Beijing Normal University

Determining the location of earthquake emergency shelters and the allocation of affected population to them are key issues that face shelter planning and emergency management. To solve this emergency shelter location–allocation problem, evacuation time and the construction cost of shelters—both influenced by the evacuation population size and its spatial distribution—are two important considerations. In this article, a mathematical model with two objectives—to minimize total weighted evacuation time(TWET) and total shelter area(TSA)—is allied with a modified particle swarm optimization algorithm to address the problem. The relationships between evacuation population size, evacuation time, and total shelter area are examined using Jinzhan Town in Chaoyang District of Beijing, China, as a case study. The results show that TWET has a power function relationship with TSA under different population size scenarios, and a linear function applies between evacuation population and TWET under different TSAs. The joint relationships of TSA, TWET, and population size show that TWET increases with population increase and TSA decrease, and compared with TSA, population influences TWET more strongly. Given a reliable projection of population change and spatial planning of a study area, this method can be useful for government decision making on the location of earthquake emergency shelters and on the allocation of evacuees to those shelters.

关键词： China,earthquake shelter location Evacuation population allocation Total shelter area Total weighted evacuation time

Effects of Oxygen on the Microstructure of Ti_(47)Al_(0.7)B Alloys

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Journal of Materials Science & Technology 2010年第2期26卷 131-135页

作者： Yingche Ma Zhiguo Jiang Bo Chen xiujuan zhao Ming Gao Kui Liu Yiyi Li Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The effects of oxygen on the microstructure of Ti-47Al-0.7B （at. pct） alloy for as-cast automotive valves were investigated. Six alloys with oxygen content from 0.4 to 1.4 at. pct were prepared by induction melting and centrifugal casting in CaO crucible under protective atmosphere. The microstructures were observed by optical microscopy （OM） and scanning electron microscope （SEM）. The results show that the increase of oxygen content led to grain refinement and enhanced the microhardness as well as the α2 volume fraction in the TiAl-based alloys.

关键词： Microstructure Oxygen content Grain refinement TiAl-based alloys

Twinned substructure in lath martensite of water quenched Fe-0.2%C and Fe-0.8%C steels

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Journal of Materials Science & Technology 2020年第14期47卷 126-132页

作者： Haidong Sun Yuhui Wang Zuohua Wang Ning Liu Yan Peng xiujuan zhao Ruiming Ren Hongwang Zhang National Engineering Research Center for Equipment and Technology of Cold Strip Rolling College of Mechanical EngineeringYanshan UniversityQinhuangdao066004China Liren College of Yanshan University Yanshan UniversityQinhuangdao066004China School of Materials Science&Engineering Dalian Jiaotong UniversityDalian116028China

In the present investigation,twinned substructures within lath martensite of two water quenched steels(0.2 wt.%C and 0.8 wt.%C)were *** lath martensite has typical hierarchical packet-block-lath with dislocation ***,laths that are misoriented by/70.5°or/60° and bordered by{011}plane,namely twinned laths,are observed,of which the density increases and the scale decreases as more carbons were *** twinned laths have body centered cubic(bcc)crystal structure,belonging to twinned variants following the classical Kurdjumov-Sachs(K-S)orientation relationship with respect to the parent *** bcc{112}twins,twinned variants produce strong double diffraction and in turn the extra diffraction spots that are commonly observed in the martensite in steels with wide range of carbon contents.

关键词： Twinned variant Lath martensite Double electron diffraction Orientation relationship Steels

Inhibition of PKB/Akt activity involved in apigenin-induced apoptosis in human gastric carcinoma cells

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Chinese Science Bulletin 2007年第16期52卷 2226-2232页

作者： YUAN LinHong XIA Wei zhao xiujuan ZHANG XiaoHua ZHANG Ling WU Kun Department of Nutrition and Food Hygiene School of Public Health Harbin Medical University Harbin 150081 China Department of Nutrition and Food Hygiene School of Public Health and Family MedicineCapital Medical University Beijing100061 China

Apigenin is a flavonoid widely distributed in fruits and vegetables. It possesses growth inhibitory properties against numerous cancer cell lines. However,the molecular mechanism(s) by which api-genin elicits its effects have not been fully elucidated. Here we studied whether apigenin inhibits growth and induces apoptosis in human gastric carcinoma cells. We showed that the flavonoid inhibited growth of the cells and caused apoptosis,as evidenced by DNA Ladder,cleavage of pro-caspase-3 in a time-dependent manner. Induction of apoptosis was dependent on inhibition of the PKB/Akt activity. We found that while apigenin had no effect on the expression of Akt and Bad,it inhibited specific phosphorylation of the two proteins that are associated with pro-survival mechanisms. We propose that this important flavonoid induces apoptosis in gastric cancer cells by inhibiting Akt activity. Since Akt is often activated in cancers,our findings may have clinical implications.

关键词：胃癌细胞凋亡 PKB/Akt 类黄酮分子机制

Pollution levels, composition characteristics and sources of atmospheric PM2.5 in a rural area of the North China Plain during winter

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Journal of Environmental Sciences 2020年第9期32卷 172-182页

作者： Xiaoxi zhao xiujuan zhao Pengfei Liu Can Ye Chaoyang Xue Chenglong Zhang Yuanyuan Zhang Chengtang Liu Junfeng Liu Hui Chen Jianmin Chen Yujing Mu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Institute of Urban Meteorology Chinese Meteorological AdministrationBeijing 100089China Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science and EngineeringFudan UniversityShanghai 200433China Key Laboratory of Atmospheric Chemistry China Meteorological AdministrationBeijing 100081China

The pollution levels,composition characteristics and sources of atmospheric PM2.5 were investigated based on field measurement at a rural site in the North China Plain(NCP) from pre-heating period to heating period in winter of *** hourly average concentrations of PM2.5 frequently exceeded 150 μg/m3 and even achieved 400 μg/m3,indicating that the PM2.5pollution was still very serious despite the implementation of stricter control measures in the rural *** with the pre-heating period,the mean concentrations of organic carbon(OG),element carbon(EC) and chlorine ion(Cl-) during the heating period increased by 20.8%,36.6% and 38.8%,accompanying with increments of their proportions in PM2.5from 37.5%,9.8% and 5.5% to 42.9%,12.7% and 7.2%,*** significant increase of both their concentrations and proportions during the heating period was mainly ascribed to the residential coal *** proportions of sulfate,nitrate and ammonium respectively increased from 9.9%,10.9% and 9.0% in nighttime to 13.8%,16.2% and 11.1% in daytime,implying that the daytime photochemical reactions made remarkable contributions to the secondary inorganic *** simulation results from WRF-Chem revealed that the emission of residential coal combustion in the rural area was underestimated by the current emission *** sources identified by positive matrix factorization(PMF) based on the measurement were residential coal combustion,secondary formation of inorganic aerosols,biomass burning,vehicle emission and raising dust,contributing to atmospheric PM2.5 of 40.5%,21.2%,16.4%,10.8%,8.6% and 2.5%,respectively.

关键词： pollution winter characteristics