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Characterization for commutators of n-dimensional fractional Hardy operators

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Science China Mathematics 2007年第10期50卷 1418-1426页

作者： Zun-wei FU~(1,2) Zong-guang liu~3 Shan-zhen LU~(1+) Hong-bin WANG~3 ~1 school of mathematical sciences,beijing normal university,beijing 100875,China ~2 Department of Mathematics,Linyi normal university,Linyi 276005,China ~3 Department of Mathematics,China university of Mining and Technology (beijing),beijing 100083,China school of mathematical sciences Beijing Normal University Beijing China Department of Mathematics Linyi Normal University Linyi China Department of Mathematics China University of Mining and Technology (Beijing) Beijing China

In this paper,it was proved that the commutator H_(β,b)generated by an n-dimensional fractional Hardy operator and a locally integrable function b is bounded from L^(p1)(R^n)to L^(p2)(R^n)if and only if b is a CMO(R^... 详细信息

关键词： n-dimensional fractional Hardy operator, commutator, C(M)O function, homogeneous Herz space

Patterns of magpie nest utilization by a nesting raptor community in a secondary forest

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Progress in Natural Science:Materials International 2009年第10期19卷 1253-1259页

作者： Tong Zhou a,Haitao Wang a,c,Yu liu b,Fumin Lei c,wei Gaoa,a Key Laboratory of Vegetation Ecology,Ministry of Education,school of Life sciences,Northeast normal university,Changchun 130024,China b Natural History Museum,Northeast normal university,Changchun 130117,China c Institute of Zoology,Chinese Academy of sciences,beijing 100101,China Key Laboratory of Vegetation Ecology Ministry of Education School of Life Sciences Northeast Normal University Changchun 130024 China Institute of Zoology Chinese Academy of Sciences Beijing 100101 China Natural History Museum Northeast Normal University Changchun 130117 China

For a total of 9 years,we examined the patterns of a nesting raptor community that utilized European Magpie(Pica pica) nests in the Zuojia Natural Reserve,northeast *** raptor species and two other bird species were recorded nesting in magpie *** reuse rate of abandoned magpie nests was 51.6%,and the number of reused nests was positively correlated with their *** utilized 83.3% of the reused abandoned magpie *** followed for more than 1 year were reused by raptors an average of 1.13 ***-specific nest usurpation was common,with 17.3% of new magpie nests being usurped by raptors,and four cases of usurpation occurred among different raptor *** the community level,8 of 11 raptor species took over magpie nests to breed in the study area,and 91.9% of their nests came from magpie *** Magpies represent the core species in the nest web of the local raptor community that utilizes magpie *** the forest stand level,closer proximity to forest edges and greater distances from occupied raptor nests were the best predictors of nest *** the nest-site level,arbor density and canopy coverage were the best predictors of nest reuse.

关键词： European Magpie Nest reuse Nest usurpation Raptor community

GENETIC DIVERSITY AMONG CHINESE SIKA DEER (CERVUS NIPPON) POPULATIONS AND RELATIONSHIPS BETWEEN CHINESE AND JAPANESE SIKA DEER

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Chinese Science Bulletin 2006年第4期51卷 433-440页

作者： Lü Xiaoping wei Fuwen LIMing yang Guang liu Hai Key Laboratory for Animal Ecology and Conservation Biology Insti-tute of Zoology Chinese Academy of Sciences Beijing 100080China Graduate school of the Chinese Academy of sciences Beijing 100039China Institute of Genetic Resources Nanjing Normal University Nanjing 210097 China

Sika deer (Cervus nippon) is a cervid endemic to mainland and insular Asia and endan-gered. We analyzed variation in the mitochondrial DNA (mtDNA) control region for four subspecies to understand the genetic diversity, population structure and evolutionary history in China. 335 bp were se-quenced and eight haplotypes were identified based on 25 variable sites among the populations. Sika deer in China showed lower genetic diversity, sug-gesting a small effective population size due to habi-tat fragmentation, a low number of founder individu-als, or the narrow breeding program. AMOVA analy-sis indicated that there was significant genetic subdi-vision among the four populations, but no correlation between the genetic and geographic distance. Phy-logenetic analyses also revealed that Chinese sika deer may be divided into three genetic clades, but the genetic structure among Chinese populations was inconsistent with subspecies designations and pre-sent geographic distribution. Including the sequence data of Japanese sika deer, the results indicated that Chinese populations were more closely related to Southern Japanese populations than to the Northern Japanese one, and the Taiwan population was closer to populations of Northeastern China and Sichuan than to those of Southern China.

关键词：中国梅花鹿遗传多样性衔接重复数量日本梅花鹿

Putin Visits China to Boost Sino-Russian Economic and Trade Ties

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China's Foreign Trade 2012年第7期 61-63页

作者： wei Hao, Associate Professor and Doctor from the Economics and Business Administration school of beijing normal university liu Shibin, Master from the Economics and Business Administration school of beijing normal university

During June 5-7 of 2012, the Russian President Putin paid an state visit to China for the first time since his resuming

关键词： Russian visit deepen bilateral emerging strategic

Deep proteome profiling promotes whole proteome characterization and drug discovery for esophageal squamous cell carcinoma

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Cancer Biology & Medicine 2022年第3期19卷 273-277页

作者： wei liu yongping Cui Wen liu Zhihua liu Liyan Xu Enmin Li College of Science Heilongjiang Institute of TechnologyHarbin 150050China Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology the Key Laboratory of Molecular Biology for High Cancer Incidence Coastal Chaoshan AreaShantou University Medical CollegeShantou 515041China Department of Pathology Key Laboratory of Cellular Physiology(Shanxi Medical University)Ministry of EducationTaiyuan 030001China Fujian Provincial Key Laboratory of Innovative Drug Target Research School of Pharmaceutical SciencesXiamen UniversityXiamen 361005China State Key Lab of Molecular Oncology National Cancer Center/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

Proteins are key players in various cellular *** the ultimate executors of cellular processes,they play essential roles in linking genotypes to *** in protein expression and post-translational modifications(PTMs)are closely associated with the initiation and development of cancer,and they carry biological information inaccessible to genomics and *** complements genomic and transcriptomic data,thus enabling comprehensive analysis of cancer pathogenesis and accelerating biomedical research2.

关键词： esophageal linking carry

RAIN INTENSITY DISTRIBUTION IN THE SPLASH REGION OF ATOMIZED FLOW

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Journal of Hydrodynamics 2006年第3期18卷 362-366页

作者： DUAN Hong-dong liu Shi-he LUO Qiu-shi HUANG wei school of Water Resource and Hydropower Wuhan University Wuhan 430072China Water Resources and Hydropower Planning and Design General Institute MWR Beijing 100011 China

Atomized flow is an unnatural two-phase flow produced while water discharges in water release structures. This flow might threaten the normal operation of hydraulic and hydroelectric installations owing to the unnatural and high-density rain as well as the unnatural and dirty mist. The splash region, the region with the highest rain intensity, hence should receive much attention during the design and operation of the hydraulic and hydroelectric installations. In this paper rain intensity distribution in the splash region of the atomized flow is investigated experimentally, and the method of random simulation is used to predict the rain intensity distribution in the splash region.

关键词： atomized flow splash rain intensity

Preparation and properties of nanosize MnZn ferrite from δ-FeOOH

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Rare Metals 2006年第Z1期25卷 466-470页

作者： HAO Shunli WANG Xin wei Yu Wang Yongming liu Chunjing school of Material and Engineering Hebei University of Technology Tianjin 300130 China 　 College of Chemistry Hebei Normal University Shijiazhuang 050016 China 　　

Ferrous ion was transformed into feroxyhyte (δ-FeOOH) by oxidation. Then, manganese sulfate and zinc sulfate in some ratio were added to the feroxyhyte solution. The co-precipitation was boiling reflux conditions sometime under constant stirring. The nanosize MnZn ferrite powder was formed. The mechanism of preparation of the nanosize MnZn ferrite was discussed, and the formation of feroxyhyte which was playing a key role during the process was mentioned. The properties of powder was tested by means of X-ray diffraction, transmission electron microscopy and vibrating sample magnetometer. The results show that the samples of spherical particles about 20 nm, which have characteristics of ferrimagnetism, has larger saturation magnetization, but the remanent magnetization and coercivity are comparatively smaller. The spinel MnZn ferrite nanosize powder was successfully prepared from δ-FeOOH at low temperature, with low-carbon steel and peroxide as main material.

关键词： nanosize MnZn ferrite feroxyhyte preparation characterization

An inexact risk management model for agricultural land-use planning under water shortage

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Frontiers of Earth Science 2016年第3期10卷 419-431页

作者： wei LI Changchun FENG Chao DAI yongping LI Chunhui LI Ming liu College of Urban and Environmental Science Peking University Beijing 100871 China College of Environmental Science and Engineering Peking University Beijing 100871 China Sino-Canada Resources and Environmental Research Academy North China Electric Power University Beijing 102206 China school of Environment Beijing Normal University Beijing 100875 China

Water resources availability has a significant impact on agricultural land-use planning, especially in a water shortage area such as North China. The random nature of available water resources and other uncertainties in an agricultural system present risk for land-use planning and may lead to undesirable decisions or potential economic loss. In this study, an inexact risk management model （IRM） was developed for supporting agricultural land-use planning and risk analysis under water shortage. The IRM model was formulated through incorporating a conditional value-at-risk （CVaR） constraint into an inexact two-stage stochastic programming （ITSP） framework, and could be used to control uncertainties expressed as not only probability distributions but also as discrete intervals. The measure of risk about the second-stage penalty cost was incorporated into the model so that the trade-off between system benefit and extreme expected loss could be analyzed. The developed model was applied to a case study in the Zhangweinan River Basin, a typical agricultural region facing serious water shortage in North China. Solutions of the IRM model showed that the obtained first-stage land-use target values could be used to reflect decision-makers＇ opinions on the long-term devel- opment plan. The confidence level a and maximum acceptable risk loss fl could be used to reflect decision- makers＇ preference towards system benefit and risk control. The results indicated that the IRM model was useful for reflecting the decision-makers＇ attitudes toward risk aversion and could help seek cost-effective agricul- tural land-use planning strategies under complex uncer- tainties.

关键词： agricultural land-use planning risk manage-ment CVaR uncertainty water shortage

Einstein Probe discovery of EP240408a: A peculiar X-ray transient with an intermediate timescale

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 222-240页

作者： Wenda Zhang weimin Yuan Zhixing Ling Yong Chen Nanda Rea Arne Rau Zhiming Cai Huaqing Cheng Francesco Coti Zelati Lixin Dai Jingwei Hu Shumei Jia Chichuan Jin Dongyue Li Paul O’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei yang Bing Zhang Chen Zhang Shuang-Nan Zhang Yonghe Zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier Liming Dou Rob Eyles-Ferris Zhou Fan Hua Feng Shaoyu Fu Johan P.U.Fynbo Lluis Galbany Saurabh W.Jha Shuaiqing Jiang Albert Kong Erik Kuulkers weihua Lei Wenxiong Li Bifang liu Mingjun liu Xing liu Yuan liu Zhu liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria Lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian Zhang Zipei Zhu Hu Zou Congying Bao Fansheng Chen Houlei Chen Tianxiang Chen wei Chen Yehai Chen Yifan Chen Chenzhou Cui weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei Han Dongjie Hou Haibo Hu Maohai Huang Jia Huo Zhenqing Jia Bowen Jiang Ge Jin Chengkui Li Junfei Li Longhui Li Maoshun Li wei Li Zhengda Li Tianying Lian Congzhan liu Heyang liu Huaqiu liu Fangjun Lu Laidan Luo Jia Ma Xuan Mao Haiwu Pan Xin Pan Liming Song Hui Sun Yunyin Tan Qingjun Tang Yihan Tao Hao Wang Juan Wang Lei Wang Wenxin Wang Yilong Wang Yusa Wang Qinyu Wu Haitao Xu Jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan Haonan yang Xiongtao yang Yanji yang Juan Zhang Mo Zhang Wenjie Zhang Zhen Zhang Zhen Zhang Ziliang Zhang Donghua Zhao Haisheng Zhao Xiaofan Zhao Zijian Zhao Hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu National Astronomical Observatories Chinese Academy of sciences school of Astronomy and Space sciences university of Chinese Academy of sciences Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of sciences Institute of Space sciences (ICE) CSIC Institut d’Estudis Espacials de Catalunya (IEEC) Max Planck Institute for Extraterrestrial Physics Innovation Academy for Microsatellites Chinese Academy of sciences Department of Physics university of Hong Kong school of Physics and Astronomy university of Leicester school of Physics and Astronomy Sun Yat-sen university Department of Physics Anhui normal university Shanghai Institute of Technical Physics Chinese Academy of sciences Physics Department Tsinghua university Nevada Center for Astrophysics university of Nevada Las Vegas Department of Physics and Astronomy university of Nevada Las Vegas South African Astronomical Observatory Department of Astronomy university of Cape Town Department of Physics university of the Free State Université Paris Cité CNRS Astroparticule et Cosmologie Université Paris Cité CEA Paris-Saclay IRFU/DAp-AIM Department of Astronomy Guangzhou university Cosmic Dawn Center (DAWN) Niels Bohr Institute university of Copenhagen Department of Physics and Astronomy Rutgers the State university of New Jersey Institute for Cosmic Ray Research The university of Tokyo ESA/ESTEC Department of Astronomy school of Physics Huazhong university of Science and Technology INAF-Osservatorio Astrofisico di Torino Sydney Institute for Astronomy school of Physics The university of Sydney Department of Astronomy Xiamen university Institute for Frontiers in Astronomy and Astrophysics beijing normal university Department of Astronomy university of Science and Technology school of Astronomy and Space sciences university of Science and Technology of China Institute of Deep Space sciences Deep Space Exploration Laboratory Department of Astronomy school of Physics and Astronomy Yunnan university Shanghai Astronomical Observatory Chi

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe （EP） and follow-up studies made with EP,Swift,NICER,GROND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope （WXT） on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for *** flare reached a peak flux of 3.9×10-9erg cm-2s-1in 0.5-4 ke V,～300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 ke V,with a power-law photon index varying *** X-ray light curve shows a plateau lasting for ～4 d,followed by a steep decay till becoming undetectable ～10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of～10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词： X-ray transients ${\bm~{Einstein~~Probe}}$