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122篇 您的检索式:作者名="Wenqing Yang"
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1Mapping wetland changes in China between 1978 and 2008显示文摘Four wetland maps for all China have been produced,based on Landsat and CBERS-02B remote sensing data between 1978 and 2008 (1978,1990,2000 and 2008).These maps were mainly developed by manual interpretation and validated by substantial field investigation in 2009.Based on these maps,we analyzed the 2008 wetland distribution in China and discussed wetland changes and their drivers over the past 30 years.(i) There were about 324097 km 2 of wetlands in 2008,for which inland marshes or swamps were the most common wetland type (35%),with lakes (26%) second.Most of the wetlands were in Heilongjiang,Inner Mongolia,Qinghai and Tibet,occupying about 55% of the national wetland area.(ii) From 1978 to 2008,China's wetland area continually and significantly decreased,by about 33% based on changes in the wetland map.This was in sharp contrast to the increase in artificial wetlands,which increased by about 122%.Inland marshes accounted for the main loss of total wetlands from 1978 to 2000.From 2000 through 2008,riverine and lacustrine wetlands constituted the main wetland loss.Fortunately however,the rate of wetland loss decreased from 5523 to 831 km 2 /a.(iii) The change ratio of lost natural wetlands (including inland and coastal wetlands) to non-wetlands has decreased slightly over the past 30 years.From 1978 to 1990,nearly all natural wetlands (98%) lost were transformed into non-wetlands.However,the ratio declined to 86% from 1990 to 2000,and to 77% from 2000 to 2008.(iv) All Chinese provinces were divided into three groups according to patterns of wetland changes,which could relate to the driving forces of such changes.Tibet was completely different from other provinces,as it was one representative example in which there was a net wetland increase,because of global warming and decreased human activity since 1990.Increased economic development caused considerable wetland loss in most eastern provinces,and artificial wetlands increased.NIU ZhenGuo ZHANG HaiYing WANG XianWei YAO WenBo ZHOU DeMin ZHAO KuiYi ZHAO Hui LI NaNa HUANG HuaBing LI CongCong YANG Jun LIU CaiXia LIU Shuang WANG Lin LI Zhan YANG ZhenZhong QIAO Fei ZHENG YaoMin CHEN YanLei SHENG YongWei GAO XiaoHong ZHU WeiHong WANG WenQing WANG Hong WENG YongLing ZHUANG DaFang LIU JiYuan LUO ZhiCai CHENG Xiao GUO ZiQi GONG Peng 2012Chinese Science Bulletin2012,57,22:51
2On the tuning of electrical and thermal transport in thermoelectrics: an integrated theory–experiment perspective显示文摘During the last two decades,we have witnessed great progress in research on thermoelectrics.There are two primary focuses.One is the fundamental understanding of electrical and thermal transport,enabled by the interplay of theory and experiment;the other is the substantial enhancement of the performance of various thermoelectric materials,through synergistic optimisation of those intercorrelated transport parameters.Here we review some of the successful strategies for tuning electrical and thermal transport.For electrical transport,we start from the classical but still very active strategy of tuning band degeneracy(or band convergence),then discuss the engineering of carrier scattering,and finally address the concept of conduction channels and conductive networks that emerge in complex thermoelectric materials.For thermal transport,we summarise the approaches for studying thermal transport based on phonon–phonon interactions valid for conventional solids,as well as some quantitative efforts for nanostructures.We also discuss the thermal transport in complex materials with chemical-bond hierarchy,in which a portion of the atoms(or subunits)are weakly bonded to the rest of the structure,leading to an intrinsic manifestation of part-crystalline part-liquid state at elevated temperatures.In this review,we provide a summary of achievements made in recent studies of thermoelectric transport properties,and demonstrate how they have led to improvements in thermoelectric performance by the integration of modern theory and experiment,and point out some challenges and possible directions.Jiong Yang Lili Xi Wujie Qiu Lihua Wu Xun Shi Lidong Chen Jihui Yang Wenqing Zhang Ctirad Uher David J Singh 2016npj Computational Materials2016,,1:24
3The Reference Genome Sequence of Scutellaria baicalensis Provides Insights into the Evolution of Wogonin Biosynthesis显示文摘Scutellaria baicalensis Georgi is important in Chinese traditional medicine where preparations of dried roots,'Huang Qin,' are used for liver and lung complaints and as complementary cancer treatments. We report a high-quality reference genome sequence for S. baicalensis where 93% of the 408.14-Mb genome has been assembled into nine pseudochromosomes with a super-N50 of 33.2 Mb. Comparison of this sequence with those of closely related species in the order Lamiales, sesamum indicum and Salvia splendens,revealed that a specialized metabolic pathway for the synthesis of 4'-deoxyflavone bioactives evolved in the genus Scu-tellaria. We found that the gene encoding a specific cinnamate coenzyme A ligase likely obtained its newfunc- tion following recent mutations, and that four genes encoding enzymes in the 4'-deoxyflavone pathway are present as tandem repeats in the genome of S. baicalensis. Further analyses revealed that gene duplications, segmental duplication, gene amplification, and point mutations coupled to gene neo- and subfunctionaliza-tions were involved in the evolution of 4'-deoxyflavone synthesis in the genus Scutellaria. Our study not only provides significant insight into the evolution of specific flavone biosynthetic pathways in the mint family, Lamiaceae, but also will facilitate the development of tools for enhancing bioactive productivity by metabolic engineering in microbes or by molecular breeding in plants. The reference genome of S. baicalensis is also useful for improving the genome assemblies for other members of the mint family and offers an important foundation for decoding the synthetic pathways of bioactive compounds in medicinal plants.Qing Zhao Jun Yang Meng-Ying Cui Jie Liu Yumin Fang Mengxiao Yan Wenqing Qiu Huiwen Shang Zhicheng Xu Reheman Yidiresi Jing-Ke Weng Tomas Pluskal Marielle Vigouroux Burkhard Steuernagel Yukun Wei Lei Yang Yonghong Hu Xiao-Ya Chen Cathie Martin 2019Molecular Plant2019,12,7:23
4Screening for gastric cancer in China:Advances,challenges and visions显示文摘Gastric cancer(GC)is one of the major cancers in China and all over the world.Most GCs are diagnosed at an advanced stage with unfavorable prognosis.Along with some other countries,China has developed the government-funded national screening programs for GC and other major cancers.GC screening has been shown to effectively decrease the incidence of and mortality from GC in countries adopting nationwide screening programs(Japan and Korea)and in studies based on selected Chinese populations.The screening of GC relies mostly on gastroendoscopy,the accuracy,reliability and safety of which have been indicated by previous studies.However,considering its invasive screening approach,requirements on skilled endoscopists and pathologists,and a high cost,developing noninvasive methods to amend endoscopic screening would be highly needed.Numerous studies have examined biomarkers for GC screening and the combination of biomarkers involving pepsinogen,gastrin,and Helicobacter pylori antibodies has been proposed for risk stratification,seeking to narrow down the high-risk populations for further endoscopy.Despite all the achievements of endoscopic screening,evidence on appropriate screening age,intervals for repeated screening,novel biomarkers promoting precision prevention,and health economics need to be accumulated to inform policymakers on endoscopic screening in China.With the guide of Health China 2030 Planning Outline,we have golden opportunities to promote prevention and control of GC.In this review,we summarize the characteristics of screening programs in China and other East Asian countries and introduce the past and current approaches and strategies for GC screening,aiming for featuring the latest advances and key challenges,and illustrating future visions of GC screening.Xiaohan Fan Xiangxiang Qin Yang Zhang Zhexuan Li Tong Zhou Jingying Zhang Weicheng You Wenqing Li Kaifeng Pan 2021Chinese Journal of Cancer Research2021,33,2:21
5Utilization of polysaccharides as depressants for the flotation separation of copper/lead concentrate显示文摘The interaction mechanism between dextrin and minerals has been investigated through micro-flotation, adsorption density measurements, Fourier transform infrared ray (FTIR) spectroscopic studies and dissolution tests. Dextrin shows a good depressing action towards galena but not chalcopyrite. FTIR spectroscopic studies indicate that dextrin chemically adsorbed on galena surface in alkaline pH range. Dissolution tests confirm leaching action of metal ions from chalcopyrite and galena surfaces, and dextrin-lead ion interaction. Adsorption measurements present that the higher adsorption density of O-isopropyl-N-ethyl thionocarbamate (IPETC) onto chalcopyrite than that onto galena, and IPETC adsorbed on galena decrease with increasing dextrin concentrations in the presence of dextrin, attesting the flotation results.Qin Wenqing Wei Qian Jiao Fen Yang Congren Liu Ruizeng Wang Peipei Ke Lifang 2013International Journal of Mining Science and Technology2013,23,2:16
6A structural view of the antibiotic degradation enzyme NDM-1 from a superbug显示文摘Gram-negative Enterobacteriaceae with resistance to carbapenem conferred by New Delhi metallo-β-lactamase 1(NDM-1)are a type of newly discovered antibioticresistant bacteria.The rapid pandemic spread of NDM-1 bacteria worldwide(spreading to India,Pakistan,Europe,America,and Chinese Taiwan)in less than 2 months characterizes these microbes as a potentially major global health problem.The drug resistance of NDM-1 bacteria is largely due to plasmids containing the blaNDM-1 gene shuttling through bacterial populations.The NDM-1 enzyme encoded by the blaNDM-1 gene hydrolyzes β-lactam antibiotics,allowing the bacteria to escape the action of antibiotics.Although the biological functions and structural features of NDM-1 have been proposed according to results from functional and structural investigation of its homologues,the precise molecular characteristics and mechanism of action of NDM-1 have not been clarified.Here,we report the threedimensional structure of NDM-1 with two catalytic zinc ions in its active site.Biological and mass spectroscopy results revealed that D-captopril can effectively inhibit the enzymatic activity of NDM-1 by binding to its active site with high binding affinity.The unique features concerning the primary sequence and structural conformation of the active site distinguish NDM-1 from other reported metallo-β-lactamases(MBLs)and implicate its role in wide spectrum drug resistance.We also discuss the molecular mechanism of NDM-1 action and its essential role in the pandemic of drug-resistant NDM-1 bacteria.Our results will provide helpful information for future drug discovery targeting drug resistance caused by NDM-1 and related metallo-β-lactamases.Yu Guo Jing Wang Guojun Niu Wenqing Shui Yuna Sun Honggang Zhou Yaozhou Zhang Cheng Yang Zhiyong Lou Zihe Rao 2011Protein & Cell2011,2,5:16
7COVID-19 Outbreak Caused by Contaminated Packaging of Imported Cold-Chain Products—Liaoning Province,China,July 2020显示文摘Summary What is known about this topic?Few major outbreaks of coronavirus disease 2019(COVID-19)have occurred in China after major nonpharmaceutical interventions and vaccines have been deployed and implemented.However,sporadic outbreaks that had high possibility to be linked to cold chain products were reported in several cities of China..What is added by this report?In July 2020,a COVID-19 outbreak occurred in Dalian,China.The investigations of this outbreak strongly suggested that the infection source was from COVID-19 virus-contaminated packaging of frozen seafood during inbound unloading personnel contact.What are the implications for public health practice?Virus contaminated paper surfaces could maintain infectivity for at least 17–24 days at-25℃.Exposure to COVID-19 virus-contaminated surfaces is a potential route for introducing the virus to a susceptible population.Countries with no domestic transmission of COVID-19 should consider introducing prevention strategies for both inbound travellers and imported goods.Several measures to prevent the introduction of the virus via cold-chain goods can be implemented.Huilai Ma1 Jianqun Zhang Ji Wang Ying Qin Cao Chen Yang Song Liang Wang Jun Meng Lingling Mao Fengqin Li Ning Li Jian Cai Yong Zhang Dayan Wang Yunting Xia Hong Wang Shaofeng Jiang Xiang Zhao Peihua Niu Wenjie Tan Tao Ma Yecheng Yao Naiying Mao Zhen Zhu Tianjiao Ji Qian Yang Baoying Huang Li Zhao Jianxing Yu Li Bai Shuangli Zhu Dongyan Wang Yan Zhang Yingwei Sun Mingchun Luan Yanhai Wang Haibo Sun Shihong Yang Zhijian Bo Xiang Ren Zhongjie Li George Fu Gao Wei Yao Wenqing Yao Zijian Feng Wenbo Xu 2021China CDC weekly2021,3,21:16
8The boundary layer characteristics in the heavy fog formation process over Beijing and its adjacent areas显示文摘By utilizing the Atmospheric Boundary Layer (ABL) observational data made available from the project '973' under the auspices of the Ministry of Science and Technology of the People's Republic of China - entitled the Beijing City Air Pollution Observation Field Experiment (BECAPEX), including the measurements by a wind profiler, captive airships, tower-based boundary layer wind and temperature gradient observational instruments (ultrasonic anemometers and electronic thermometers), air composition samplers, conventional upper-air, surface and Automatic Weather Stations (AWS) observations, this paper herewith analyzes, in a comprehensive manner, the occurrence of a heavy fog event over Beijing in February 2001, including its formation, development, persistence, dynamic and thermodynamic features as well as evolving stratification structures within the boundary layer at different stages. The results suggested: (i) as a typical case of urban heavy fog, before the fog onset over Beijing, a temperature inversion existed in the lower atmosphere, the smokes and the pollutants like SO2 and NO2 had been accumulated at a lower level. Proceeding the fog event, with the increase of SO2 and NO2 concentrations, condensability increased sharply. On the contrary, during the fog process, with increasing condensability, SO2 and NO2 concentrations decreased. This indicated that, acting as condensation nucleus, these accumulated pollutants were playing a key role in catalyzing the fog condensation. (ii) By analyzing mean gradient-, pulsation- and turbulence-distribution patterns derived from the wind measurements taken by the aforementioned tower-based instruments, they all indicated that about 10 hours before the fog onset, a signal foretelling potential strong disturbances in the lower boundary layer was detected, and a significant rise of both mean and disturbance kinetic energies was observed, revealing that the low-level wind shear was strengthened before the fog onset, consequently creating a favorable condition for the outbreak of turbulences. This strong signal seemed to be very meaningful in monitoring and predicting fog occurrence and its development. (iii) Once the fog was in shape, its condensation feedback effects tended to lift the height of temperature inversion layer within the mid and upper levels of the lower atmosphere, which in return determined the fog persistence and restructuring process.ZHANG Guangzhi, BIAN Lingeng, WANG Jizhi, YANG Yuanqin, YAO Wenqing & XU Xiangde HWL of Chinese Academy of Meteorological Sciences, Beijing 10008, China National Meteorological Center, Beijing 100081, China 2005Science China Earth Sciences2005,48,z2:12
9Data mining-aided materials discovery and optimization显示文摘Recent developments in data mining-aided materials discovery and optimization are reviewed in this paper,and an introduction to the materials data mining(MDM)process is provided using case studies.Both qualitative and quantitative methods in machine learning can be adopted in the MDM process to accomplish different tasks in materials discovery,design,and optimization.State-of-the-art techniques in data mining-aided materials discovery and optimization are demonstrated by reviewing the controllable synthesis of dendritic Co_(3)O_(4) superstructures,materials design of layered double hydroxide,battery materials discovery,and thermoelectric materials design.The results of the case studies indicate that MDM is a powerful approach for use in materials discovery and innovation,and will play an important role in the development of the Materials Genome Initiative and Materials Informatics.Wencong Lu Ruijuan Xiao Jiong Yang Hong Li Wenqing Zhang 2017Journal of Materiomics2017,3,3:11
10A systematic review of metabolomic profiling of gastric cancer and esophageal cancer显示文摘Objective:Upper gastrointestinal(UGI)cancers,predominantly gastric cancer(GC)and esophageal cancer(EC),are malignant tumor types with high morbidity and mortality rates.Accumulating studies have focused on metabolomic profiling of UGI cancers in recent years.In this systematic review,we have provided a collective summary of previous findings on metabolites and metabolomic profiling associated with GC and EC.Methods:A systematic search of three databases(Embase,PubMed,and Web of Science)for molecular epidemiologic studies on the metabolomic profiles of GC and EC was conducted.The Newcastle–Ottawa Scale(NOS)was used to assess the quality of the included articles.Results:A total of 52 original studies were included for review.A number of metabolites were differentially distributed between GC and EC cases and non-cases,including those involved in glycolysis,anaerobic respiration,tricarboxylic acid cycle,and protein and lipid metabolism.Lactic acid,glucose,citrate,and fumaric acid were among the most frequently reported metabolites of cellular respiration while glutamine,glutamate,and valine were among the most commonly reported amino acids.The lipid metabolites identified previously included saturated and unsaturated free fatty acids,aldehydes,and ketones.However,the key findings across studies to date have been inconsistent,potentially due to limited sample sizes and the majority being hospital-based case-control analyses lacking an independent replication group.Conclusions:Studies on metabolomics have thus far provided insights into etiological factors and biomarkers for UGI cancers,supporting the potential of applying metabolomic profiling in cancer prevention and management efforts.Sha Huang Yang Guo Zhexuan Li Yang Zhang Tong Zhou Weicheng You Kaifeng Pan Wenqing Li 2020Cancer Biology & Medicine2020,17,1:11
11Effect of N fertilization rate on soil alkalihydrolyzable N, subtending leaf N concentration,fiber yield, and quality of cotton显示文摘Soil alkali-hydrolyzable nitrogen, which is sensitive to N fertilization rate, is one of the indicators of soil nitrogen supplying capacity. Two field experiments were conducted in Dongtai(120°19″ E, 32°52″ N), Jiangsu, China in 2009 and Dafeng(120°28″ E, 33°12″ N), Jiangsu province, China in 2010. Six nitrogen rates(0, 150, 300, 375, 450, and 600 kg ha^(-1)) were used to study the effect of N fertilization rate on soil alkali-hydrolyzable nitrogen content(SAHNC), subtending leaf nitrogen concentration(SLNC), yield, and fiber quality. In both Dongtai and Dafeng experiment station, the highest yield(1709 kg ha^(-1)), best quality(fiber length 30.6 mm, fiber strength 31.6 c N tex^(-1), micronaire 4.82), and highest N agronomic efficiency(2.03 kg kg^(-1)) were achieved at the nitrogen fertilization rate of 375 kg ha^(-1). The dynamics of SAHNC and SLNC could be simulated with a cubic and an exponential function,respectively. The changes in SAHNC were consistent with the changes in SLNC. Optimal average rate(0.276 mg day^(-1)) and duration(51.8 days) of SAHNC rapid decline were similar to the values obtained at the nitrogen rate of 375 kg ha^(-1)at which cotton showed highest fiber yield, quality, and N agronomic efficiency. Thus, the levels and strategies of nitrogen fertilization can affect SAHNC dynamics. The N fertilization rate that optimizes soil alkali-hydrolyzable nitrogen content would optimize the subtending leaf nitrogen concentration and thereby increase the yield and quality of the cotton fiber.Binglin Chen Hongkun Yang Weichao Song Chunyu Liu Jiao Xu Wenqing Zhao Zhiguo Zhou 2016The Crop Journal2016,4,4:8
12An Epidemic of Hepatitis A--Liaoning Province,2020显示文摘What is already known about this topic?Hepatitis A(HA)is caused by acute hepatitis A virus(HAV)infection and was once very common in China.Following the 2008 introduction of the HA vaccine into the national Expanded Program on Immunization(EPI),the incidence of reported HA in China decreased markedly.However,HA epidemics still occur in Liaoning Province every 3–5 years,although with far fewer cases than in the pre-HA-vaccination era.What is added by this report?Between January 1,2020 and March 18,2020,the number of reported cases of HA in Dalian and Dandong cities of Liaoning Province increased significantly compared with the same period in previous years.All cases were sporadic,and cases were seen in nearly every township.The increase in HA occurred one month after local fresh seafood became available with most cases being among adults.A casecontrol study showed that consuming raw or undercooked seafood,clams,snapping shrimp,and oysters were significantly associated with the increase in HA.What are the implications for public health practices?Strengthening health education for residents to avoid consumption of raw seafood and encouraging HAV vaccination of adults aged 20 to 54 years are important to prevent periodic HAV endemic outbreaks.Further multisectoral cooperation must be emphasized on HA surveillance in areas with a high prevalence of HA.Jing Sun Yuanqiu Li Xing Fang Yan Wang Yinan Han Yang Liu Jingyuan Cao Wenting Zhou Hui Zheng Wenqing Yao 2020China CDC weekly2020,2,30:7
13Aerodynamic performance enhancement forflapping airfoils by co-flow jet显示文摘Introducing active flow control into the design of flapping wing is an effective way to enhance its aerodynamic performance.In this paper,a novel active flow control technology called Co-Flow Jet(CFJ)is applied to flapping airfoils.The effect of CFJ on aerodynamic performance of flapping airfoils at low Reynolds number is numerically investigated using Unsteady Reynolds Averaged Navier-Stokes(URANS)simulation with Spalart-Allmaras(SA)turbulence model.Numerical methods are validated by a NACA6415-based CFJ airfoil case and a S809 pitching airfoil case.Then NACA6415 baseline airfoil and NACA6415-based CFJ airfoil with jet-off and jet-on are simulated in flapping motion,with Reynolds number 70,000 and reduced frequency 0.2.As a result,CFJ airfoils with jet-on generally have better lift and thrust characteristics than baseline airfoils and jet-off airfoil when Cμgreater than 0.04,which results from the CFJ effect of reducing flow separation by injecting high-energy fluid into boundary layer.Besides,typical kinematic and geometric parameters,including the reduced frequency and the positions of the suction and injection slot,are systematically studied to figure out their influence on aerodynamic performance of the CFJ airfoil.And a variable Cμjet control strategy is proposed to further improve effective propulsive efficiency.Compared with using constant Cμ,an increase of effective propulsive efficiency by22.6%has been achieved by using prescribed variable CμNACA6415-based CFJ airfoil at frequency 0.2.This study may provide some guidance to performance enhancement for Flapping wing Micro Air Vehicles(FMAV).Tao WU Bifeng SONG Wenping SONG Wenqing YANG Zhonghua HAN 2020Chinese Journal of Aeronautics2020,33,10:7
14Studies of the Genotoxicity of Glycidyl Methacrylate (GMA)显示文摘The following experiments were conducted to evaluate the genotoxic effects of GMA (glycidyl methacrylale) on mammalian and human cells.(1) Using the absorption spectrum shift method in vitro, we observed that the maximums of calf thymus DNA and GMA were shifted toward longer wavelengths (a change of more than 15nm) and the absorbance decreased after incubation at room temperature for 15min or more.The result indicates that binding of DNA and GMA had occurred.The binding force is strong, not affected by the addition of concentrated sodium chloride solution, and only slightly decreased by the addition of 8 M urea solution.Therefore the bond between DNA and GMA might be covalent.(2) In cell cultures, unscheduled DNA synthesis (UDS) in human and/or rat lymphocyte was induced and DNA semiconserva-tive replication was inhibited by GMA at concentrations of less than 5.2 mM.(3) Sperm abnormality tests and assays of UDS in germ cells of male mice were conducted to study the in vivo genotoxicity of GMA.The results revealed that GMA could damage DNA, increase sperm abnormality frequency, and reduce the number of sperm cells, 1990 Academic Press.Inc.DAYING XIE, WEI ZHANG, LAIFU CAO, WENQING SUN, ZHONGSHENG LI, QING GAO, YILI WU, HUILAN GAO, HUIFANG YANG, JIM ZUO,~* AND FUDE FANG~* Institute oF Occupational Medicine. Chinese Academy ol Preventive Medicine. Beijing 100050. and *Institute of Basic Medical Sciences, Chinese Academy ol Medical Sciences. Beijing 100730, China 1990Biomedical and Environmental Sciences1990,3,3:7
15Optimization of Dimples in Microchannel Heat Sink with Impinging Jets Part A: Mathematical Model and the Influence of Dimple Radius显示文摘With increasing heat fluxes caused by electronic components, dimples have attracted wide attention by researchers and have been applied to microchannel heat sink in modern advanced cooling technologies. In this work, the combination of dimples, impinging jets and microchannel heat sink was proposed to improve the heat transfer performance on a cooling surface with a constant heat flux 500 W/cm^2. A mathematical model was advanced for numerically analyzing the fluid flow and heat transfer characteristics of a microchannel heat sink with impinging jets and dimples(MHSIJD), and the velocity distribution, pressure drop, and thermal performance of MHSIJD were analyzed by varying the radii of dimples. The results showed that the combination of dimples and MHSIJ can achieve excellent heat transfer performance; for the MHSIJD model in this work, the maximum and average temperatures can be as low as 320 K and 305 K, respectively when mass flow rate is 30 g/s; when dimple radius is larger than 0.195 mm, both the heat transfer coefficient and the overall performance h/ΔP of MHSIJD are higher than those of MHSIJ.MING Tingzhen CAI Cunjin YANG Wei SHEN Wenqing GAN Ting 2018Journal of Thermal Science2018,27,3:7
16The effects of span-wise and chord-wise flexibility on the aerodynamic performance of micro flapping-wing显示文摘The flexibility of flapping-wing strongly affects the aerodynamic performance of Flapping-wing Micro Air Vehicle (FMAV),and the deformations in span-wise and chord-wise directions are coupled together in flight.In this study,the flexible deformation is formulated in span-wise and chord-wise separately in order to analyze its effects on aerodynamic behavior.The preconditioned Navier-Stokes equations based on chimera grid are used in the computational fluid dynamics method to study the aerodynamic effects caused by flexible deformation,and the simulation results are compared with experimental test to illustrate the capability of above method.Based on our results,it is clearly showed that the span-wise flexible deformation should be limited in a small range to achieve higher aerodynamic performance and the chord-wise deformation could enhance the aerodynamic performance.The results also suggest that FMAV designers should design the flapping-wing with high stiffness leading edge to limit the span-wise deformation,and more flexible chord ribs to keep chord-wise deformation in suitable range.YANG WenQing SONG BiFeng SONG WenPing WANG LiGuang 2012Chinese Science Bulletin2012,57,22:6
17Reemergent Cases of COVID-19--Dalian City,Liaoning Province,China,July 22,2020显示文摘From July 22-23,3 local COVID-19 cases were reported in Dalian City,Liaoning Province,China.All 3 patients reported that they did not leave Dalian 14 days before the onset of disease and had no COVID-19 case contact history and no foreign personnel contact history.Epidemiological investigation,medical isolation,and nucleic acid detection was immediately carried out in Dalian,and 12 asymptomatic infections were detected in close contacts of Patient 1.Because asymptomatic infections made up a large proportion of total infections,the outbreak was likely observed in the beginning stages.Xiang Zhao Lingling Mao Jianqun Zhang Yong Zhang Yang Song Zhijian Bo Hong Wang Ji Wang Cao Chen Jinbo Xiao Tianjiao Ji Qian Yang Wenbo Xu Dayan Wang Wenqing Yao 2020China CDC weekly2020,2,34:5
18Vertical Distribution Characteristics of PM2.5 Observed by a Mobile Vehicle Lidar in Tianjin, China in 2016显示文摘We present mobile vehicle lidar observations in Tianjin, China during the spring, summer, and winter of 2016. Mobile observations were carried out along the city border road of Tianjin to obtain the vertical distribution characteristics of PM_(2.5). Hygroscopic growth was not considered since relative humidity was less than 60% during the observation experiments. PM_(2.5) profile was obtained with the linear regression equation between the particle extinction coefficient and PM_(2.5) mass concentration. In spring, the vertical distribution of PM_(2.5) exhibited a hierarchical structure. In addition to a layer of particles that gathered near the ground, a portion of particles floated at 0.6–2.5-km height. In summer and winter, the fine particles basically gathered below 1 km near the ground. In spring and summer, the concentration of fine particles in the south was higher than that in the north because of the influence of south wind. In winter, the distribution of fine particles was opposite to that measured during spring and summer. High concentrations of PM_(2.5) were observed in the rural areas of North Tianjin with a maximum of 350 μg m–3 on 13 December2016. It is shown that industrial and ship emissions in spring and summer and coal combustion in winter were the major sources of fine particles that polluted Tianjin. The results provide insights into the mechanisms of haze formation and the effects of meteorological conditions during haze–fog pollution episodes in the Tianjin area.Lihui LYU Yunsheng DONG Tianshu ZHANG Cheng LIU Wenqing LIU Zhouqing XIE Yan XIANG Yi ZHANG Zhenyi CHEN Guangqiang FAN Leibo ZHANG Yang LIU Yuchen SHI Xiaowen SHU 2018Journal of Meteorological Research2018,32,1:5
19Crustal Motion Characteristics in the Eastern Margin of the Tibetan Plateau and Adjacent Regions after the Wenchuan Earthquake显示文摘The Wenchuan earthquake has altered the crustal motion characteristics in the eastern margin of the Tibetan Plateau and adjacent regions.Using discontinuous GPS survey data for 2008–2012, the velocity field for the Eurasia reference framework has been obtained, and the general trend of contemporary crustal motion after the occurrence of the Wenchuan earthquake has been studied.In addition, using the velocity field, the block movement velocity has been estimated by least-squares fitting.Furthermore, the properties and displacement rates of main faults have been obtained from the differences in velocity vectors of the blocks on both sides of the faults.The results reveal that there are no obvious changes in the general characteristics of crustal motion in this area after the Wenchuan earthquake.The earthquake mainly changed the rate of the movement of the Chuan-Qing block and caused variation in the movement direction of the South China block.The effect of the earthquake on faults is mainly reflected in variations in fault displacement velocity; there is no fundamental change in the properties of fault activity.The displacement rates of the Xianshuihe fault decreased by 3–4 mm/a, the Longmenshan fault increased by 9–10 mm/a, and the northern segment of the Anninghe fault increased by approximately 9 mm/a.Furthermore, the displacement rates of the Minjiang, Xueshan, Huya, Longquanshan, and Xinjin faults increased by 2–3 mm/a.This implies that the effects of the Wenchuan earthquake on crustal movement can mainly be observed in the Chuan-Qing, South China, and N-Chuan-Dian blocks and their internal faults, as well as the Xianshuihe and Longmenshan faults and the northern section of the Anninghe fault.The reason for this is that the Wenchuan earthquake disturbed the kinematic and dynamic balance in the region.TANG Wenqing ZHANG Qingzhi PAN Zhongxi LI Jun YANG Cheng 2015Acta Geologica Sinica(English Edition)2015,89,5:5
20Radiotherapy combined with nimotuzumab for elderly esophageal cancer patients:A phaseⅡclinical trial显示文摘Objective:To investigate the safety and efficacy of nimotuzumab combined with radiotherapy for elderly patients with non-resectable esophageal carcinoma(EC).Methods:Eligible patients were aged 70 years or older and had treatment-naive,histologically proven inoperable locally advanced EC.Enrolled patients received radiotherapy with a total dose of 50-60 Gy in 25-30 fractions,concurrent with weekly infusion of nimotuzumab.The primary end point was the rate of more than grade 3 toxicities.Results:From June 2011 to July 2016,46 patients with stageⅡ-IV EC with a median age of 76.5 years were enrolled.There were 10,28 and 8 patients with stageⅡ,III and IV disease,respectively.The common acute toxicities included esophagitis(grade 1-2,75.4%;grade 3,8.7%),pneumonitis(grade 1,4.3%;grade 2,6.5%;grade3,2.2%),leukopenia(grade 1-2,60.9%;grade 3-4,4.4%),gastrointestinal reaction(grade 1-2,17.3%;grade 3,2.2%),thrombocytopenia(grade 1-2,21.7%;grade 3,2.2%),and radiothermitis(grade 1-2,39.2%).The incidence of grade 3-4 adverse effects was 17.4%.No grade 5 toxicities were observed.Clinical complete response,partial response,stable disease,and progressive disease were observed in 1(2.2%),31(67.4%),12(26.1%),and 2(4.3%)patients,respectively.The median overall survival(OS)and progression-free survival(PFS)were 17 and 10 months,respectively.The 2-,3-,and 5-year OS and PFS rates were 30.4%,21.7%,19.6%,and 26.1%,19.6%,19.6%,respectively.Conclusions:Nimotuzumab combined with radiotherapy is a safe and effective therapy for elderly patients who are not surgical candidates.Further studies are warranted to confirm its therapeutic effects in elderly EC patients.Xu Yang Yirui Zhai Nan Bi Tao Zhang Lei Deng Wenqing Wang Xin Wang Dongfu Chen Zongmei Zhou Luhua Wang Jun Liang 2021Chinese Journal of Cancer Research2021,33,1:4
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