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Effect of water level fluctuations on temporal-spatial patterns of foraging activities by the wintering Hooded Crane(Grus monacha)

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Chinese Birds 2015年第3期6卷 169-177页

作者： Dongmei Zhang Lizhi Zhou Yunwei song School of Resources and Environmental Engineering Anhui University Institute of Biodiversity and Wetland Ecology Anhui University Anhui Biodiversity Information Center Shengjin Lake National Nature Reserve of Anhui Province

Background:The yangtze River floodplain provides important wintering habitats for Hooded Cranes(Grus monacha) in *** in the water level change foraging habitat and food availability,affecting their temporal-spatial patterns of foraging *** is of considerable importance to investigate the effect of these fluctuations on food availability for wintering Hooded Cranes and their foraging response to these *** their behavior patterns is beneficial in protecting the wintering crane population and restoring their wintering ***:A field survey of the winter behavior of cranes was carried out at Shengjin Lake from November in 2013 to April in *** variables,as well as the spatial distribution and behavior patterns of wintering cranes at their foraging sites during five stages of water level fluctuation were *** on this data we analyzed the relationship of foraging behavior relative to water level fluctuations and habitat ***:The foraging habitats used by Hooded Cranes varied at the different water level *** the water level decreased,the use of meadows and mudflats *** the water dropped to its lowest level,the use by the Hooded Crane in the mudflats reached a *** were statistically significant differences in time budget in the three types of habitats over the five stages of the water *** the mudflats,the foraging behavior and maintenance behavior varied significantly with the water level,while the alert behavior showed little *** of a generalized linear model showed that the five water level stages and three habitat types had a significant effect on foraging behavior,while the combined effect of these two variables was significant on the foraging time budget and the length of foraging activity of the Hooded ***:With the decrease in the water level,the use of mudflats by Hooded Cranes increased *** availability in differ

关键词： Water level fluctuations Foraging activity Temporal-spatial pattern Hooded Crane Grus monacha

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Tumor Molecular Imaging with Nanoparticles

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Engineering 2016年第1期2卷 132-140页

作者： Zhen Cheng Xuefeng ya Xilin Sun BaozhongShen Sanjiv Sam Gambhir a Molecular Imaging Program at Stanford Department of Radiology Stanford University Stanford CA 94305 USA Molecular Imaging Research Center of Harbin Medical University Harbin 150001 China TOF-PET/CT/MR Center the Fourth Hospital of Harbin Medical University Harbin 150001 China ora Umverslty Stanford CA 94305 USA

Molecular imaging(MI)can provide not only structural images using traditional imaging techniques but also functional and molecular information using many newly emerging imaging *** the past decade,the utilization of nanotechnology in MI has exhibited many significant advantages and provided new opportunities for the imaging of living *** is expected that multimodality nanoparticles(NPs)can lead to precise assessment of tumor biology and the tumor *** review addresses topics related to engineered NPs and summarizes the recent applications of these nanoconstructs in cancer optical imaging,ultrasound,photoacoustic imaging,magnetic resonance imaging(MRI),and radionuclide *** challenges involved in the translation of NPs to the clinic are discussed.

关键词： Tumor Molecular imaging Nanoparticles

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Numerical investigation of flow mechanisms of tandem impeller inside a centrifugal compressor

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Chinese Journal of Aeronautics 2019年第12期32卷 2627-2640页

作者： Ziliang LI Xin’gen LU Shengfeng ZHAO ge HAN Chengwu yaNG yanfeng ZHANG Key Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

This study numerically investigated a single stage centrifugal compressor "Radiver" with a wedge diffuser and several tandem-designed impellers to explore the flow phenomena within the tandem impeller and the potential to enhance compressor *** results demonstrate that tandem design and clocking fraction(ks)significantly affects the compressor *** compressor stage with tandem impellers of Series A of boundary layer growth interruption alone are observed to have a widely operating range but efficiency and total pressure ratio penalty compared with that of conventional *** tandem impeller with at least the same impeller efficiency as the conventional design is considered as a critical design criteria so that further modification process based on the flow characteristic of tandem impeller is *** order to restrain the inducer wake and exducer shock losses,parameters modification of blade angle and thickness distributions are necessary and the modified tandem impeller of Series B is *** modified tandem impeller with 25%clocking arrangement shows an 8.45%stall margin increase and maintains the total pressure ratio and efficiency as the conventional design,which proves the potential of tandem impeller to improve compressor stage *** is noteworthy that the tandem impellers of Radiver have not shown obviously balanced exit flow field and the fundamental mechanism of stall margin extending of tandem impeller lies on the improved impeller/diffuser matching performance resulting from the incidence angle variation at diffuser inlet.

关键词： Centrifugal compressor stage Flow mechanism Impeller/diffuser matching Stall margin Tandem impeller

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geochemistry of sandstones from the Neoproterozoic Jinshanzhai Formation in northern Anhui Province, China: Provenance, weathering and tectonic setting

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Chinese Journal Of geochemistry 2013年第1期32卷 95-103页

作者： SUN Linhua GUI Herong CHEN song School of Earth Science and Engineering Suzhou University

Sandstones from the Neoproterozoic Jinshanzhai Formation in northern Anhui Province, China, were analyzed for major oxides and trace elements to infer their provenance, the intensity of paleo-weathering of their source rocks and the depositional tectonic setting. Diagrams of (SiO2/20)-(Na2O+K2O)-(MgO+TiO2+FeO*), TiO2-Ni, Th-Hf-Co, Hf-La/Th and some ratios of elements indicate that felsic rocks constitute the source rocks in the provenance. The values of Chemical Index of Alteration (CIA) are low, which are considered to be affected by K-metasomatism. Whereas the high CIW (Chemical Index of Weathering) values indicate intensive weathering of the source material. Plots of sandstones on bivariate and triangle discriminant diagrams, as well as ICV (Index of Compositional Variation) values revealed that they were deposited on a passive continental margin or in an intra-plate basin. Our recent study, in combination with previous studies and the research progress of the Rodinia super continent, demonstrated that the convergence and extension of the Rodinia super continent were preserved by twice extension as expressed by petrological variation of the southeastern margin of the North China Craton (NCC) during the Neoproterozoic.

关键词：沉积构造背景中国北方新元古代地球化学特征安徽省 Rodinia超大陆砂岩耐候性

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Semi-empirical Likelihood Confidence Intervals for the Differences of Quantiles with Missing Data

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Acta Mathematica Sinica,English Series 2009年第5期25卷 845-854页

作者： Yong song QIN Jun Chao ZHANG School of Mathematical Sciences Guangxi Normal University Guilin 541004 P. R. China Department of Mathematics Harbin University Harbin 150086 P. R. China

Detecting population （group） differences is useful in many applications, such as medical research. In this paper, we explore the probabilistic theory for identifying the quantile differences .between two populations. Suppose that there are two populations x and y with missing data on both of them, where x is nonparametric and y is parametric. We are interested in constructing confidence intervals on the quantile differences of x and y. Random hot deck imputation is used to fill in missing data. Semi-empirical likelihood confidence intervals on the differences are constructed.

关键词： empirical likelihood confidence interval quantile missing data hot deck imputation

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Self-contained eigenvector algorithm applied to the identification of aerodynamic derivatives of bridge model

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Science China(Technological Sciences) 2011年第5期54卷 1134-1140页

作者： ZHANG XiaoXu CHEN LiFen song HanWen Department of Mechanics and Engineering Science Fudan University Shanghai 200433 China School of Aerospace Engineering and Applied Mechanics Tong[i University Shanghai 200092 China

On one hand, when the bridge stays in a windy environment, the aerodynamic power would reduce it to act as a non-classic system. Consequently, the transposition of the system’s right eigenmatrix will not equal its left eigenmatrix any longer. On the other hand, eigenmatrix plays an important role in model identification, which is the basis of the identification of aerodynamic derivatives. In this study, we follow Scanlan’s simple bridge model and utilize the information provided by the left and right eigenmatrixes to structure a self-contained eigenvector algorithm in the frequency domain. For the purpose of fitting more accurate transfer function, the study adopts the combined sine-wave stimulation method in the numerical simulation. And from the simulation results, we can conclude that the derivatives identified by the self-contained eigenvector algorithm are more dependable.

关键词： bridge model – aerodynamic derivatives – eigenvector – modal analysis – parameter identification

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Microstructure and corrosion resistance of Fe/Mo composite amorphous coatings prepared by air plasma spraying

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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 657-662页

作者： Chao-ping Jiang ya-zhe Xing Feng-ying Zhang Jian-min Hao Engineering Research Center of Transportation Materials (Ministry of Education) School of Materials Science and Engineering Chang'an University Xi'an 710064China

Fe/Mo composite coatings were prepared by air plasma spraying （APS） using Fe-based and Mo-based amorphous and nanocrys- talline mixed powders. Microstructural studies show that the composite coatings present a layered structure with low porosity due to adding the self-bonded Mo-based alloy. Corrosion behaviors of the composite coatings, the Fe-based coatings and the Mo-based coatings were in- vestigated by electrochemical measurements and salt spray tests. Electrochemical results show that the composite coatings exhibit a lower polarization current density and higher corrosion potentials than the Fe-based coating when tested in 3.5wt% NaC1 solutions, indicating supe- rior corrosion resistance compared with the Fe-based coating. Also with the increase in addition of the Mo-based alloy, a raised corrosion re- sistance, inferred by an increase in corrosion potential and a decrease in polarization current density, can be found. The results of salt spray tests again show that the corrosion resistance is enhanced by adding the Mo-based alloy, which helps to reduce the porosity of the composite coatings and enhance the stability of the passive films.

关键词： composite coatings plasma spraying amorphous corrosion resistance microstructure

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On Two-stage Estimate Based on Independent Estimate of Covariance Matrix

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Acta Mathematica Sinica,English Series 2006年第1期22卷 283-288页

作者： Su Ju YIN song Gui WANG College of Applied Sciences Beijing University of Technology Beijing 100022 P. R. China

When an independent estimate of covariance matrix is available, we often prefer two-stage estimate （TSE）. Expressions of exact covarianee matrix of the TSE obtained by using all and some covariables in eovariance adjustment approach are given, and a necessary and sufficient condition for the TSE to be superior to the least square estimate and related large sample test is also established. Furthermore the TSE, by using some covariables, is expressed as weighted least square estimate. Basing on this fact, a necessary and sufficient condition for the TSE by using some covariables to be superior to the TSE by using all eovariables is obtained. These results give us some insight into the selection of covariables in the TSE and its application.

关键词： two-stage estimate covariance adjusted estimate canonical correlation coefficients

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Simulation of the spread of infectious diseases in a geographical environment

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Science China Earth Sciences 2009年第4期52卷 550-561页

作者： ZHONG ShaoBo HUANG QuanYi song DunJiang Department of Engineering Physics Tsinghua UniversityBeijing 100084China Institute of Policy and Management Chinese Academy of SciencesBeijing 100190China

The study of mathematical models for the spread of infectious diseases is an important issue in epidemiology. Given the fact that most existing models cannot comprehensively depict heterogeneities (e.g., the population heterogeneity and the distribution heterogeneity) and complex contagion patterns (which are mostly caused by the human interaction induced by modern transportation) in the real world, a theoretical model of the spread of infectious diseases is proposed. It employs geo-entity based cel-lular automata to simulate the spread of infectious diseases in a geographical environment. In the model, physical geographical regions are defined as cells. The population within each cell is divided into three classes: Susceptible, Infective, and Recovered, which are further divided into some sub-classes by states of individuals. The transition rules, which determine the changes of proportions of those subclasses and reciprocal transformation formulas among them, are provided. Through defining suitable spatial weighting functions, the model is applied to simulate the spread of the infectious dis-eases with not only local contagion but also global contagion. With some cases of simulation, it has been shown that the results are reasonably consistent with the spread of infectious diseases in the real world. The model is supposed to model dynamics of infectious diseases on complex networks, which is nearly impossible to be achieved with differential equations because of the complexity of the prob-lem. The cases of simulation also demonstrate that efforts of all kinds of interventions can be visual-ized and explored, and then the model is able to provide decision-making support for prevention and control of infectious diseases.

关键词： cellular automata infectious disease modeling geographic information systems spatial weighting function

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Succinate dehydrogenase-deficient gastrointestinal stromal tumors

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World Journal of Gastroenterology 2015年第8期21卷 2303-2314页

作者： ya-Mei Wang Meng-Li Gu Feng Ji Department of Gastroenterology The First Affiliated Hospital of Zhejiang University

Most gastrointestinal stromal tumors(GISTs)are characterized by KIT or platelet-derived growth factor alpha(PDGFRA)activating ***,there are still 10%-15%of GISTs lacking KIT and PDGFRA mutations,called wild-type GISTs(WT GISTs).Among these so-called WT GISTs,a small subset is associated with succinate dehydrogenase(SDH)deficiency,known as SDH-deficient *** addition,GISTs that occur in Carney triad and Carney-Stratakis syndromerepresent specific examples of SDH-deficient ***-deficient GISTs locate exclusively in the stomach,showing predilection for children and young adults with female *** tumor generally pursues an indolent course and exhibits primary resistance to imatinib therapy in most *** of succinate dehydrogenase subunit B expression and overexpression of insulin-like growth factor 1 receptor(IGF1R)are common features of SDH-deficient *** WT GISTs without succinate dehydrogenase activity,upregulation of hypoxia-inducible factor 1αmay lead to increased growth signaling through IGF1R and vascular endothelial growth factor receptor(VEGFR).As a result,IGF1R and VEGFR are promising to be the novel therapeutic targets of *** review will update the current knowledge on characteristics of SDH-deficient GISTs and further discuss the possible mechanisms of tumorigenesis and clinical management of SDH-deficient GISTs.

关键词： Gastrointestinal stromal tumors Succinate dehydrog

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