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

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 [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

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

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Uniqueness and local stability for the inverse scattering problem of determining the cavity

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science china Mathematics 2005年第8期48卷 1113-1123页

作者： FENG Lixin & MA Fuming LMAM, school of Mathematical sciences, Peking university, Beijing 100871, china school of Mathematical sciences, Heilongjiang university, Harbin 150080, china school of Mathematical sciences, Jilin university, changchun 130012, china 1. LMAM School of Mathematical Sciences Peking University 100871 Beijing China 2. school of Mathematical sciences Heilongjiang University 150080 Harbin China 3. school of Mathematical sciences Jilin University 130012 Changchun China

Considering a time-harmonic electromagnetic plane wave incident on an arbitrarily shaped open cavity embedded in infinite ground plane, the physical process is modelled by Maxwell's equations. We investigate the inverse problem of determining the shape of the open cavity from the information of the measured scattered field. Results on the uniqueness and the local stability of the inverse problem in the 2-dimensional TM (transverse magnetic) polarization are proved in this paper.

关键词： uniqueness, stability, Maxwell's equations, inverse scattering problem.

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Measurement of the linear electro-optic coefficient of a minute cBN sample

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science china(Technological sciences) 2005年第2期48卷 233-340页

作者： DOU Qingping1, , MA Haitao1, JIA Gang1, CHEN Zhanguo1 2 & ZHANG Tiechen3 1. College of Electronic science and Engineering, State Key Laboratory on Integrated Optoelectronics, Jilin university, changchun 130023, china 2. Mudanjiang normal Institute, Mudanjiang 157012, china 3. State Key Laboratory of Superhard Materials, Jilin university, changchun 130012, china 1. College of Electronic science and Engineering State Key Laboratory on Integrated Optoelectronics Jilin University 130023 Changchun China 2. Mudanjiang normal Institute 157012 Mudanjiang China 3. State Key Laboratory of Superhard Materials Jilin University 130012 Changchun China

Cubic boron nitride (cBN) is a kind of artificial (synthetic) crystal. Transverse electro-optic modulation in a minute cBN sample was carried out. Basing on the practical form of the crystal, we established the theoretical and experimental method according to the sample. For the first time, the linear electro-optic effect was observed in cBN, and half-wave voltage of the cBN sample was measured successfully. Furthermore, its linear electro-optic coefficient was calculated at 1.17×10?14 m/V.

关键词： cBN crystal, linear electro-optic effect, half-wave voltage, linear electro-optic coefficient.

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Categories and characteristics of urban villages by GIS-based analysis:A case study of the Shenzhen Special Economic Zone

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science china(Technological sciences) 2010年第S1期53卷 150-157页

作者： TONG De1,FENG changchun2,LI GuiCai1 & CHEN Peng1,2 1S henzhen Graduate school,Peking university,Shenzhen 518055,china 2College of Urban and Environmental science,Peking university,Beijing 100871,china 1. Shenzhen Graduate school Peking University Shenzhen 518055 China 2. College of Urban and Environmental science Peking University Beijing 100871 China

Studies on the characteristics of urban villages have attracted much interest in urban ***,how to advance the development of further theoretical analysis and quantitative methodologies,especially in the era that GIS and digital-urban technologies develop rapidly and provide precious resources on spatial issues,has always been a heated debate and *** this paper,a mathematical model based on spatial analysis is introduced to deal with the categorization and characterization of urban villages.A total of 89 urban villages in the Shenzhen Special Economic Zone(SEZ)are used in this case *** ArcGIS tools on buffer analysis,distance and density calculation,and socio-economic and spatial attributes conjunction,urban villages’31 spatial variables in 4 aspects—social,economic,locational,and physical—are extracted,and 6 principal factors are concluded by principal components analysis to indicate the spatial characteristic of urban *** on the 6 principal factors,6 types of urban villages,including rapidly sprawling,large,rapidly industrializing periphery,overcrowded,intensively mobile and economically backward,are divided through the Hierarchical Clustering ***,the spatial features and formation mechanisms of each type of urban villages are ***,the advantages and the shortcomings of the methodology for this specific application are also ***,several guidelines on urban village management and renewal are provided based on the result of type *** outcome of the paper depends on the informational and technological support from the development of digital-city management,and is able to in turn provide basis on monitoring and improving urban villages which can further digital urban framework.

关键词： urban villages GIS-based analysis principal component hierarchical cluster the Shenzhen Special Economic Zone (SEZ)

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On the diophantine equation X^2-(1+a^2)Y^4 =-2a

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science china Mathematics 2010年第8期53卷 2143-2158页

作者： YUAN PingZhi 1 & ZHANG ZhongFeng 2 1 school of Mathematics,South china normal university,Guangzhou 510631,china 2 school of Mathematics & Computational science,Sun Yat-Sen university,Guangzhou 510275,china 1. school of Mathematics South China Normal University Guangzhou 510631 China2. School of Mathematics & Computational Science Sun Yat-Sen University Guangzhou 510275 China

Let a≥1 be an *** this paper,we will prove the equation in the title has at most three positive integer solutions.

关键词： algebraic approximations continued fractions elliptic curves quartic equations

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Effect of the partial substitution of Mg by Al on the crystal structure and hydrogenation behavior of La_2Mg_(17)

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Rare Metals 2007年第4期26卷 347-351页

作者： ZHANG Qing＇ an WANG changchun SI Tingzhi school of Materials science and Engineering Anhui University of Technology Maanshan 243002 China

The effect of the partial substitution of Mg by A1 on the crystal structure of La2Mg17 has been investigated. It was found that the LaEMgl7 phase disappears after the partial substitution of Mg by Al. The LaE（***0.1）17 alloy contains La（Mg,AI）12 and La（Mg,Al）2. Further increasing the Al content, the La2（Mg0.8Al0.2）17 alloy consists of La（Mg,Al）12, La（Mg,Al）2, and Mg. The La（Mg0.93Al0.07）12 phase in the La2（Mg0.9Al0.1）17 alloy crystallizes with the ThMn12-type structure in space group 14/mmm （No. 139）. The lattice parameters were determined to be a = 1.03246（7） nm and c = 0.59410（6） nm. In the ThMn12-type structure, AI atoms occupy 8f site but the A1 content is limited. Moreover, the hydrogenation character- istics have also been compared. La2Mgl7 decomposes into LaH3 and MgH2 under hydrogen, but the La（Mgo.93Alo.o7）12 phase can be hydrogenated into LaH3, MgH2, and La3Al11 at 473 K.

关键词： intermetallic compound crystal structure hydrogenation characteristic X-ray diffraction

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Identification of malignant plasma cells in the primary mediastinal large B-cell lymphoma

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science china life sciences 2024年

作者： changchun Wang Lianhui Duan Guanyin Huang Chang Yu Xuping Yang Dangchi Li Yueyu Huang Wenhui Shen Xuefei Liu Qiaoli Lü Haiyan Yang Weimin Mao An Zhao Department of Thoracic Surgery Zhejiang Cancer Hospital Hangzhou Institute of Medicine Chinese Academy of Sciences Zhejiang Key Laboratory of Diagnosis & Treatment Technology on Thoracic Oncology school of Medicine Southern University of Science and Technology Department of Pathology Zhejiang Cancer Hospital Hangzhou Institute of Medicine Chinese Academy of Sciences Department of Ecology and Evolutionary Biology University of California Los Angeles Jiangxi Key Laboratory of Tumour Metastasis of Jiangxi Health Commission Jiangxi Cancer Hospital The Second Affiliated Hospital of Nanchang Medical College Jiangxi Cancer Institute Department of Hematology Zhejiang Cancer Hospital Hangzhou Institute of Medicine Chinese Academy of Sciences Zhejiang Cancer Institute Zhejiang Cancer Hospital Hangzhou Institute of Medicine Chinese Academy of Sciences

Dear Editor,Primary mediastinal large B-cell lymphoma (PMBCL) is a rare subtype of aggressive B cell lymphoma, accounting for 2%to 4%of total non-Hodgkin’s lymphoma(NHL) cases (Savage, 2022). Genomic rearrangements (e.g., isochromosome9p) and copy-number alterations at9p24.1 loci, which contain the genes encoding programmed death-ligand 1/2(PDL1/2) and JAK2, lead to the overexpression of these genes in PMBCL,distinguishing PMBCL from diffuse large B-cell lymphoma (DLBCL)(Green et al.,2010). Recent thymic single-cell gene profiling has advanced our understanding of the presence and functions of B cells in the thymus (Afzali et al., 2024). However,the etiology of thymic B cell-derived PMBCL and its cellular microenvironment remain unknown. In this study, from a single-cell perspective, we compared the single-cell profiles of PMBCL with those of DLBCL and normal lymph nodes (NLNs),and discovered a unique phenotype of PMBCL-associated malignant plasma cells.

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Theoretical studies on Ru(fppz)_2(CO)L (L=N-heterocyclic ligand):Electronic structure,absorption,phosphorescence,and solvatochromism

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science china Chemistry 2008年第12期51卷 1211-1220页

作者： LIU Tao1, ZHOU Xin1, BAI FuQuan1, ZHANG JianPo1, XIA BaoHui1,2, PAN QingJiang3 & ZHANG HongXing1 1 State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin university, changchun 130023, china 2 College of Chemistry, Jilin university, changchun 130023, china 3 Laboratory of Physical Chemistry, school of Chemistry and Materials science, Heilongjiang university, Harbin 150080, china State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun 130023 China College of Chemistry Jilin University Changchun 130023 China Laboratory of Physical Chemistry School of Chemistry and Materials Science Heilongjiang University Harbin 150080 China

A series of ruthenium(II) complexes Ru(fppz)2(CO)L [fppz = 3-trifluoromethyl-5(2-pyridyl)pyrazole; L = pyridine (1), 4-dimethylaminopyridine (2), 4-cyanopyridine (3)] were designed and investigated theo-retically to explore their electronic structures, absorption, and emissions as well as the solvatochrom-ism. The singlet ground state and triplet excited state geometries were fully optimized at the B3LYP/LANL2DZ and CIS/LANL2DZ level, respectively. The HOMO of 1-3 is composed of dyz(Ru) atom and π(fppz). The LUMO of 1 and 2 is dominantly contributed by π*(fppz) orbital, but that of 3 is con-tributed by π*(L). Absorption and phosphorescence in vacuo, C6H12, and CH3CN media were calculated using the TD-DFT level of theory with the PCM model based on the optimized ground and excited state geometries, respectively. The lowest-lying absorption of 1 and 2 at 387 and 391 nm is attributed to {[dyz(Ru) + π(fppz)] → [π*(fppz)]} transition, but that of 3 at 479 nm is assigned to {[dyz(Ru) + π(fppz)] → [π*(L)]} transition. The phosphorescence of 1 and 2 at 436 and 438 nm originates from 3{[dyz(Ru) + π(fppz)] [π*(fppz)]} excited state, while that of 3 at 606 nm is from 3{[dyz(Ru) + π(fppz)] [π*(L)]} excited state. The calculation results showed that the absorption and emission transition character can be changed from MLCT/ILCT to MLCT/LLCT transition by altering the substituent on the L ligand. The phosphorescence of 1 and 2 does not have solvatochromism, but that of 3 at 606 nm (vacuo), 584 nm (C6H12), and 541 nm (CH3CN) is strongly dependent on the solvent polarity, so introducing elec-tron-withdrawing group on ligand L will induce remarkable solvatochromism.

关键词： ruthenium complex DFT phosphorescence solvatochromism

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A NOTE ON UPPER AND LOWER SOLUTIONS METHOD FOR FOURTH-ORDER BOUNDARY VALUE PROBLEMS

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Annals of Differential Equations 2008年第1期24卷 117-120页

作者： Zhao Hong (school of Math.,changchun normal university,changchun 130032)

In this paper,we deal with a class of boundary value *** give the existence of solution under the assumption that there exist lower and upper solutions to the *** result extends and complements the relevant ones which... 详细信息

关键词： fourth-order boundary value problem existence upper and lower solution method

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A theorem of Fong's type for graded algebras

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science china Mathematics 2005年第5期48卷 577-582页

作者： FAN Yun & ZHU Ping school of Mathematics and Statistics, Central china normal university, Wuhan 430079, china school of Mathematical science, Nankai university, Tianjin 300071, china 1. school of Mathematics and Statistics Central China Normal University 430079 Wuhan China 2. school of Mathematical science Nankai University 300071 Tianjin China

Let G be a finite p-solvable group and k be an algebraic closed field of characteristic p. It is proved that any projective indecomposable module of a G-graded k-algebra is an induced module of a module of the subalgebra graded by a Hall p′-subgroup. A necessary and sufficient condition for the indecomposability of an induced module from a Hall p′-subgroup is obtained.

关键词： group graded algebra indecomposable induced module primitive idempotent.

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