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Elevational divergence in the great tit complex revealed by major hemoglobin genes

Current Zoology 2018年第4期64卷 455-464页

作者： Xiaojia ZHu Yuyan GUAN Yanhua qu Gabriel DAVID gang SONG Fumin LEI Key Laboratory of Zoological Systematics and Evolution Institute of Zoology Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China CXishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Yunnan 666303 China

Gene flow and demographic history can play important roles in the adaptive genetic differentiation of species, which is rarely understood in the high-altitude adaptive evolution of birds. To elucidate genetic divergence of populations in the great tit complex （Parus major, P. minor and P. cinereus） at different elevations, we compared the genetic structure and gene flow in hemoglobin genes with neutral loci. Our results revealed the elevationally divergent structure of αA-globin gene, distinctive from that of the/βA-globin gene and neutral loci. We further investigated gene flow patterns among the populations in the central-northern （〉 1,000 m a.s.l.）, south-eastern （〈 1,000 m a.s.l.） regions and the Southwest Mountains （〉2,000 m a.s.l.） in China. The high-altitude （〉 1,000 m a.s.l.） diverged aA-globin genetic structure coincidαed with higher αA-globin gene flow between highland populations, in contrast to restricted neutral gene flow concordant with the phylogeny. The higher aA-globin gene flow suggests the possibility of adaptive evolution during population divergence, contrary to the lower aA-globin gene flow homogenized by neutral loci during population expantion. In concordance with patterns of historical gene flow, genotypic and allelic profiles provide distinctive patterns of fixation in different high-altitude populations. The fixation of alleles at contrasting elevations may primarily due to highland standing variants aA49Asn/72Asn/108Ala originating from the south-western population. Our findings demonstrate a pattern of genetic divergence with gene flow in major hemoglobin genes depending on population demographic history.

关键词： elevational divergence gene flow genetic structure hemoglobin gene

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A Modified qu EChERS-DART-MS/MS Technique for High-Throughput Detection of Organophosphate Nerve Agent Hydrolysis Products in Environmental Samples

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Journal of Analysis and Testing 2023年第2期7卷 163-171页

作者： gang qu Bo Chen Shilei Liu Qiaoli Zhang Yang Yang Qingshan Fu College of Material Science and Engineering Sichuan University of Science and EngineeringZigong 643000China State Key Laboratory of NBC Protection for Civilian Beijing 102205China Laboratory of Analytical Chemistry Research Institute of Chemical DefenceBeijing 102205China

Organophosphate nerve agents(OPNAs)are lethal chemical weapons(CWs)which hydrolyze rapidly to alkyl phosphate compounds in the *** identification of alkyl phosphate compounds in the environment is critical for the verification of ***,due to the complex sample preparation and long detection process for organophosphate nerve agent hydrolysis products(OPNAHPs),their high-throughput determination is *** simplify sample preparation and detection of OPNAHPs from environmental samples,a quick,easy,cheap,effective,rugged and safe(qu ECh ERS)method for the simultaneous purification of the five OPNAHPs in environmental samples combined with detection through direct analysis in real-time ionization source coupled with tandem mass spectrometer(DART-MS/MS)was *** internal standard method was applied for the *** method exhibited a good linearity(R^(2)>0.991)in the range of 1.00 ng/m L-4.00μg/m *** limits of detection and limits of quantification were 1.00-7.00 ng/m L and 10.0-20.0 ng/m L,*** recoveries of OPNAHPs in environmental samples were between 65.3%and 107%,with relative standard deviations ranged from 1.6%to 19%.In addition,the sample preparation and analysis process for OPNAHPs could be completed in less than 10 *** results demonstrated that the modified qu ECh ERS method could quickly and efficiently remove the matrix of environmental *** with DART-MS/MS,an accurate and high-throughput detection method of OPNAHPs in environmental samples was *** developed method has great potential in the fields of early warning,clinical treatment and environmental decontamination.

关键词： OPNAHPs quEChERS DART-MS/MS Environmental samples

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Innovation Governs Everything Eventually:Extensions of the DeGroot Model

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Acta Mathematicae Applicatae Sinica 2017年第1期33卷 35-42页

作者： Ming-min YANG Xing-long qu Zhi-gang CAO Xiao-guang YANG Key Laboratory of Management Decision and Information SystemsAcademy of Mathematics and Systems ScienceChinese Academy of Sciences The Research Center of Information Technology & Economic and Social Development Hangzhou Dianzi University

We study the DeGroot model for continuous opinion dynamics under the influence of innovations. In the original model, individuals＇ opinions, after given their initial values, evolve merely according to the given learning topology. The main contribution of this paper is that external innovation effects are introduced： each individual is given the opportunity to change her opinion to a randomly selected opinion according to a given distribution on the opinion space and then the external opinion is either adapted by the individual, or combined into her learning process. It turns out that all the classical results of the DeGroot model are violated in this new model. We prove that convergence can still be guaranteed in the expectation sense, regardless of the learning topology. We also study the steady distributions of opinions among the society and the time spent to reach a steady state by means of Monte-Carlo simulations.

关键词： social network non-Bayesian learning opinion dynamics DeGroot model

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Evolution of Surface Sensible Heat over the Tibetan Plateau Under the Recent Global Warming Hiatus

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Advances in Atmospheric Sciences 2017年第10期34卷 1249-1262页

作者： Lihua ZHU gang HUANG Guangzhou FAN Xia qu Guijie ZHAO Wei HUA State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China School of Atmospheric Sciences/Plateau Atmosphere and Environment Key Laboratory of Sichuan Province/Joint Laboratory of Climate and Environment Change Chengdu University of lnformation TechnologyChengdu 610225China Laboratory for Regional Oceanography and Numerical Modeling Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Joint Center for Global Change Studies Beijing 100875China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Based on regular surface meteorological observations and NCEP/DOE reanalysis data, this study investigates the evolution of surface sensible heat（SH） over the central and eastern Tibetan Plateau（CE-TP） under the recent global warming hiatus. The results reveal that the SH over the CE-TP presents a recovery since the slowdown of the global warming. The restored surface wind speed together with increased difference in ground-air temperature contribute to the recovery in *** the global warming hiatus, the persistent weakening wind speed is alleviated due to the variation of the meridional temperature gradient. Meanwhile, the ground surface temperature and the difference in ground-air temperature show a significant increasing trend in that period caused by the increased total cloud amount, especially at night. At nighttime, the increased total cloud cover reduces the surface effective radiation via a strengthening of atmospheric counter radiation and subsequently brings about a clear upward trend in ground surface temperature and the difference in ground-air ***–radiation feedback plays a significant role in the evolution of the surface temperature and even SH during the global warming hiatus. Consequently, besides the surface wind speed, the difference in ground-air temperature becomes another significant factor for the variation in SH since the slowdown of global warming, particularly at night.

关键词： surface sensible heat Tibetan Plateau ground-air temperature difference surface wind speed global warming hiatus

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Investigation on drawing process of Bi-2223/Ag wires using racetrack-type dies:Simulation and experiments

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Science China(Technological Sciences) 2009年第8期52卷 2255-2262页

作者： LU YongJin ZENG Pan LEI LiPing qu TiMing FANG gang SUN JianFeng Key Laboratory for Advanced Materials Processing Technology Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Innova Superconductor Technology Co.Ltd. Beijing 100176China

The traditional rolling process of Bi-2223/Ag wires with circular sections is an inhomogeneous process. For the purpose of achieving a uniform filaments distribution, a novel technique for round wire through racetrack-type dies during the last several passes of drawing is necessarily brought forward. In order to investigate the processing behaviors of superconducting filaments, a numerical model for the three passes of racetrack drawing was constructed, and subsequently, the optimization of three racetrack-type dies was designed based on the simulation results. Then the three passes of racetrack drawing was applied to fabricate Bi-2223/Ag tape and the density distribution of each filament of the wire was studied by Vickers microhardness. The experimental results showed that the racetrack drawing can obtain dense superconducting filaments, and improve the mechanical properties and critical current of the final tape.

关键词： racetrack-type die Bi-2223/Ag modelling

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Effects of changes in precipitation on energy and water balance in a Eurasian meadow steppe

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Ecological Processes 2019年第1期8卷 225-239页

作者： Jingyan Chen Changliang Shao Shicheng Jiang Luping qu Fangyuan Zhao gang Dong Institute of Loess Plateau Shanxi UniversityTaiyuan 030006China National Hulunber Grassland Ecosystem Observation and Research Station&Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory of Vegetation Ecology Ministry of EducationNortheast Normal UniversityChangchun 130024China Forestry Post-Doctoral Station Forest Ecology Stable Isotope CenterForestry CollegeFujian Agriculture and Forestry UniversityFuzhou350002China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China School of Life Science Shanxi UniversityTaiyuan 030006China.

Introduction:Water such as precipitation is the most critical environment driver of ecosystem processes and functions in semi-arid *** and intensity of drought and transient waterlogging are expected to increase in the meadow steppe in northeastern *** a 4-year dataset of eddy covariance flux measurements,ground measurements of biomass,phenology,and meteorological conditions,we investigated the changes in energy fluxes at multiple temporal scales and under different precipitation ***:The meadow steppe was latent heat(LE)dominated when soil water content was>0.3 m3 m−3,but switched to sensible heat(H)dominated status when soil water content fell below 0.3 m3 m−*** dominated the energy exchange of the meadow grasslands on a yearly *** precipitation had a profound impact on water-energy balance that could reduce the damages of drought by elevating deep soil *** influence of LE on waterlogging depended on timing,with increased LE at the beginning of growing season and decreased LE after *** and summer droughts resulted in different energy partitioning between latent and sensible heat energies,with spring drought dramatically decreased the LE fraction due to the change in *** contrast,summer drought had little impact on LE due to the sufficient water input from large precipitation events at the beginning of the growing ***:There existed great seasonal and interannual variabilities in energy balance and partitioning in the meadow steppe over the 4-year study period,which were strongly influenced by changes in *** water loss through latent heat was more sensitive to spring drought than to summer drought,while summer drought had negligible impact on *** contributed to LE by enhancing its values during and after the waterlogged periods at the beginning of the growing season in a dry year,but lowering its value after the waterlogged periods in growing season.

关键词： Energy balance Energy partition Precipitation change Eddy covariance Drought

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Study on intelligent control technology for forming steel pipe of pipeline with JCO process

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Science China(Technological Sciences) 2011年第10期54卷 2754-2759页

作者： ZHAO Jun LI Jian qu XiaoYang WANG gang SUN HongLei MA Rui College of Mechanical Engineering Yanshan University Qinhuangdao 066004 China Julong Steel Pipe Co. Ltd. Qinhuangdao 062658 China

Based on plastic bending engineering theory and machine vision technology, the intelligent control technology for forming steel pipe with JCO process is presented in this paper. By ‘twice pre-bending method’ in the first forming step, the springback law can be obtained. With the springback law and the target angle, the exact punch displacement which determines the formed angle in each bending step is predicted. In the succedent forming steps, the bending process is carried out with the exact punch displacement by real-time revising the springback law. And the angle error in each forming step is calculated by comparing the actual formed angle with the target angle. By conducting compensation for the last angle error in the next forming step, each precise bending process step is realized. A system of intelligent control technology for forming the steel pipe was developed. A calibration method is proposed to calculate the exterior parameters of the CCD camera, in which the equilateral triangle is em-ployed as the calibrating board and only one image needs to be captured. A mathematical model, which converts the angle in the image into the actual formed angle, is derived. The experimental results showed that the ellipticity of the formed pipes was less than 1.5% and the high-quality pipes can be manufactured without the worker's operating experience by employing the in-telligent control technology.

关键词： steel pipe of pipeline intelligent control technology calibration JCO process ellipticity

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Sample spinning to mitigate polarization artifact and interstitial-vacancy imbalance in ion-beam irradiation

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npj Computational Materials 2020年第1期6卷 107-117页

作者： Cui-Lan Ren Yang Yang Yong-gang Li Ping huai Zhi-Yuan Zhu Ju Li Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Department of Nuclear Science and Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA Key Laboratory of Interfacial Physics and Technology Chinese Academy of SciencesShanghai 201800China National Center for Electron Microscopy Molecular FoundryLawrence Berkeley National LaboratoryBerkeleyCA 94720USA Key Laboratory of Materials Physics Institute of Solid State PhysicsChinese Academy of SciencesHefei 230031China Science Island Branch of Graduate School University of Science and Technology of ChinaHefei 230026China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteShanghai 201204China Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA

Accelerator-based ion-beam irradiation has been widely used to mimic the effects of neutron radiation damage in nuclear ***,ion radiation is most often monodisperse in the incoming ions’momentum direction,leading to excessive polarization in defect distribution,while the scattering under neutron irradiation is often more isotropic and has less radiation-induced *** of the excess-polarization as well as the damage non-uniformity artifact might be crucial for making the simulation of neutron radiation by ion-beam radiation more *** this work,a general radiation polarization theory in treating radiation as external polar stimuli is established to understand the natural material responses in different contexts,and the possibility to correct the defect polarization artifact in ion-beam *** by Magic Angle Spinning in Nuclear Magnetic Resonance,we present a precise sample spinning strategy to reduce the point-defect imbalance effect in ion-beam *** can be seen that with optimized surface inclination angle and the axis of sample rotation,the vacancy-interstitial population imbalance,as well as the damage profile non-uniformity in a designated region in the target are both *** is estimated that sample spinning frequency on the order of kHz should be sufficient to scramble the ion momentum monodispersity for commonly taken ion fluxes and dose rates,which is experimentally feasible.

关键词： beam vacancy momentum

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Performances of a Stinger PDC cutter breaking granite: Cutting force and mechanical specific energy in single cutter tests

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Petroleum Science 2023年第2期20卷 1087-1103页

作者： Chao Xiong Zhong-Wei Huang huai-Zhong Shi Rui-Yue Yang gang Wu Han Chen Wen-Hao He China University of Petroleum(Beijing) Beijing102249China Dagang Oilfield Company Tianjin Gas Storage BranchTianjin300280China

The Stinger PDC cutter has high rock-breaking efficiency and excellent impact and wear resistance, which can significantly increase the rate of penetration (ROP) and extend PDC bit life for drilling hard and abrasive formation. The knowledge of force response and mechanical specific energy (MSE) for the Stinger PDC cutter is of great importance for improving the cutter's performance and optimizing the hybrid PDC bit design. In this paper, 87 single cutter tests were conducted on the granite. A new method for precisely obtaining the rock broken volume was proposed. The influences of cutting depth, cutting angle, and cutting speed on cutting force and MSE were analyzed. Besides, a phenomenological cutting force model of the Stinger PDC cutter was established by regression of experimental data. Moreover, the surface topography and fracture morphology of the cutting groove and large size cuttings were measured by a 3D profilometer and a scanning electron microscope (SEM). Finally, the rock-breaking mechanism of the Stinger PDC cutter was illustrated. The results indicated that the cutting depth has the greatest influence on the cutting force and MSE, while the cutting speed has no obvious effects, especially at low cutting speeds. As the increase of cutting depth, the cutting force increases linearly, and MSE reduces with a quadratic polynomial relationship. When the cutting angle raises from 10° to 30°, the cutting force increases linearly, and the MSE firstly decreases and then increases. The optimal cutting angle for breaking rock is approximately 20°. The Stinger PDC cutter breaks granite mainly by high concentrated point loading and tensile failure, which can observably improve the rock breaking efficiency. The key findings of this work will help to reveal the rock-breaking mechanisms and optimize the cutter arrangement for the Stinger PDC cutter.

关键词： Stinger PDC cutter Cutting force Mechanical specific energy Single cutter tests

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Class imbalance problem in short-term solar flare prediction

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Research in Astronomy and Astrophysics 2021年第9期21卷 231-236页

作者： Jie Wan Jun-Feng Fu Jin-Fu Liu Jia-Kui Shi Cheng-gang Jin huai-Peng Zhang Laboratory for Space Environment and Physical Sciences Harbin Institute of Technology School of Electrical Engineering and Automation Harbin Institute of Technology School of Energy Science and Engineering Harbin Institute of Technology

Using data-driven algorithms to accurately forecast solar flares requires reliable data *** solar flare dataset is composed of many non-flaring samples with a small percentage of flaring *** is called the class imbalance problem in data mining *** prediction model is sensitive to most classes of the original data set during ***,the class imbalance problem for building up the flare prediction model from observational data should be systematically *** at the problem of class imbalance,three strategies are proposed corresponding to the data set,loss function,and training process:TypeⅠresamples the training samples,including oversampling for the minority class,undersampling,or mixed sampling for the majority ***Ⅱusually changes the decision-making boundary,assigning the majority and minority categories of prediction loss to different ***Ⅲassigns different weights to the training samples,the majority categories are assigned smaller weights,and the minority categories are assigned larger weights to improve the training process of the prediction *** main work of this paper compares these imbalance processing methods when building a flare prediction model and tries to find the optimal *** results show that among these strategies,the performance of oversampling and sample weighting is better than other strategies in most parameters,and the generality of resampling and changing the decision boundary is better.

关键词： The Sun Sun:X-rays,gamma rays Sun:sunspots Sun:magnetic fields Sun:flares methods:data analysis

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