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Lophozonia tree cavities used for nesting by Slender-billed Parakeets(Enicognathus leptorhynchus)in the central valley of southern Chile:a potentially vanishing keystone resource

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Chinese Birds 2017年第1期8卷 25-36页

作者： thomas h.white jr. Jaime E.Jiménez Puerto Rican Parrot Recovery Program United States Fish and Wildlife ServiceBox 1600Rio GrandePR 00745USA Sub-Antarctic Biocultural Conservation Program Department of Biological SciencesUniversity of North TexasDentonTX 76201USA Sub-Antarctic Biocultural Conservation Program Department of Philosophy and ReligionUniversity of North TexasDentonTX 76201USA Omora Etnobotanical Park Universidad de MagallanesPuerto WilliamsChile

Background: The Slender-billed Parakeet(Enicognathus leptorhynchus) is a psittacine endemic to southern Chile and an obligate secondary cavity-nester. In the central valley of southern Chile, most(94%) of the known Slender-billed Parakeet nests have occurred in large, mature southern beech(Lophozonia obliqua) trees(locally known as "pellines"). As relicts of the original old-growth forests of southern Chile, most pellines have been lost due to extensive landclearing throughout the region, potentially threatening long-term persistence of the Slender-billed ***: We conducted our study in the central valley of southern Chile, near the city of Osorno during three consecutive nesting seasons(November–January, 2008–2011). Nest trees used by Slender-billed Parakeets were located by direct observation of parakeet activities and through interviews with local residents, some of whom were former parrot nest poachers. Nest cavities were accessed, inspected and measured using single-rope climbing techniques. We report means, standard errors, 95% confidence intervals and ranges for 11 cavity-related variables. We also report clutch sizes encountered in active nests, and age estimates of nest trees based on known growth rates of Lophozonia trees in southern Chile. Linear regressions were used to evaluate potential relationships between cavity-related variables and clutch ***: We located and measured 38 Lophozonia tree cavities used for nesting by Slender-billed Parakeets. Compared to those used by other psittacines, nest trees were relatively large, averaging 30.4 breast height of 134.5 ter ± 1.1 m in height with a mean diameter at ± 4.7 cm. Based on estimated annual diameincrement, ages of nest trees ranged from approximately 209–485 years. Nest cavities entrances averaged 12.5 ± 0.9 m in height above ground level. Cavity entrance widths averaged 51.0 ± 13.3 cm(vertical) by 11.5 ± 0.7 cm(horizontal). Cavity entrance orientations were apparently random, with

关键词： Conservation Deforestation habitat loss Lophozonia obliqua Pellines Psittacidae Regeneration

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Detection of Arterial Occlusions Using Viscoelastic Wave Propagation

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Advances in Applied Mathematics and Mechanics 2009年第1期1卷 1-28页

作者： h.T.Banks J.R.Samuels,jr. Center for Research in Scientific Computation North Carolina State UniversityCampus Box 8212RaleighNC 27695-8212USA

We consider the problem of detecting cardiac artery occlusions using stenosis driven viscoelastic(VE)waves propagated through biotissue to body surface *** investigate possible statistical model formulations(ordinary least squares(OLS),generalized least squares(GLS))and post analysis techniques(residual plots)to ascertain uncertainty in estimates as well as validity of the statistical models as part of a methodology for stenosis detection using viscoelastic waves.

关键词： Inverse problems viscoelastic models wave propagation in biotissue statistical models

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ERROR ESTIMATES FOR ThE TIME DISCRETIZATION FOR NONLINEAR MAXWELL'S EQUATIONS

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Journal of Computational Mathematics 2008年第5期26卷 677-688页

作者： Mavián Slodika Ján Bua jr. Department of Mathematical Analysis Ghent University

This paper is devoted to the study of a nonlinear evolution eddy current model of the type δtB（h）＋ △↓× （ △↓ × h） =0 subject to homogeneous Dirichlet boundary conditions h × v = 0 and a given initial datum. here, the magnetic properties of a soft ferromagnet are linked by a nonlinear material law described by B（h）. We apply the backward Euler method for the time discretization and we derive the error estimates in suitable function spaces. The results depend on the nonlinearity of B（h）.

关键词： Electromagnetic field Nonlinear eddy current problem Time discretization,Error estimate.

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Very weak solutions to the two-dimensional Monge-Ampére equation Dedicated to Professor Jean-Yves Chemin on the Occasion of his 60th Birthday

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Science China Mathematics 2019年第6期62卷 1041-1056页

作者： Wentao Cao László Székelyhidi jr. Institut für Mathematik Universit?t Leipzig

In this short note we revisit the convex integration approach to constructing very weak solutions to the 2D Monge-Ampére equation with h?lder-continuous ?rst derivatives of exponent β h is based on combining the approach of Lewicka and Pakzad(2017) with a new diagonalization procedure which avoids the use of conformal coordinates, which was introduced by De Lellis et al.(2018) for the isometric immersion problem.

关键词： Monge-Ampére equation convex integration weak solutions

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International Business The Challenge of Global Competition Donald A. Ball, Wendell h. McCulloch, jr., Paul L. Frantz, et al. 8th ed.

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2002年

作者： Donald A. Ball Wendell h. McCulloch jr. Paul L. Frantz et al.

Includes bibliographical references and indexes.

ISBN: (纸本)0072356766

Includes bibliographical references and indexes.

关键词： International economic relations.

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Antiviral polysaccharides isolated from hong Kong brown seaweed hydroclathrus clathratus

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Science China(Life Sciences) 2007年第5期50卷 611-618页

作者： OOI Engchoon Vincent ANG Put O jr. Department of Biology the Chinese University of Hong Kong Shatin N.T. Hong Kong SAR China

Two relatively pure polysaccharides h3-a1 and h3-b1 had been isolated from the brown seaweed hy-droclathrus clathratus. They were characterized by hPLC, ultraviolet scanning, gas chromatography, infrared spectroscopy and elemental analysis, and shown to be two different sulfated polysaccharides with different monosaccharide content, but both with high relative molecular mass. They contained some proteins and uronic acid respectively. The sulfate content and bioactivity of these polysaccha-rides varied during purification. The fractions derived from the hot water extract also exhibited low anticoagulant effect. This is the first time that the antiherpetic and anticoagulant activities were evaluated for the polysaccharides from the hong Kong brown seaweed hydroclathrus clathratus.

关键词： hong Kong seaweed, hydroclathrus clathratus, antiviral polysaccharide, polysaccharide characterization

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A Phase-Field Model Coupled with Lattice Kinetics Solver for Modeling Crystal Growth in Furnaces

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Communications in Computational Physics 2014年第1期15卷 76-92页

作者： Guang Lin Jie Bao Zhijie Xu Alexandre M.Tartakovsky Charles h.henager jr. Computational Mathematics Group Pacific Northwest National LaboratoryRichlandWA 99352 USA. Fluid and Computational Engineering Group Northwest National LaboratoryRichlandWA 99352 USA. Engineering Mechanics and Structure Materials Group Northwest National LaboratoryRichlandWA 99352 USA.

In this study,we present a new numerical model for crystal growth in a vertical solidification *** model takes into account the buoyancy induced convective flow and its effect on the crystal growth *** evolution of the crystal growth interface is simulated using the phase-field method.A semi-implicit lattice kinetics solver based on the Boltzmann equation is employed to model the unsteady incompressible *** model is used to investigate the effect of furnace operational conditions on crystal growth interface profiles and growth *** a simple case of macroscopic radial growth,the phase-field model is validated against an analytical *** numerical simulations reveal that for a certain set of temperature boundary conditions,the heat transport in the melt near the phase interface is diffusion dominant and advection is suppressed.

关键词： Phase-field crystal growth diffusion convection lattice kinetics modeling

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high-Resolution 3-D Radar Imaging through Nonuniform Fast Fourier Transform(NUFFT)

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Communications in Computational Physics 2006年第1期1卷 176-191页

作者： Jiayu Song Qing h.Liu Kangwook Kim Waymond R.Scott,jr. Department of Electrical and Computer Engineering Duke UniversityDurhamNC 27708USA School of Electrical and Computer Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

This paper applies a 3-D nonuniform fast Fourier transform(NUFFT)migration method to image both free-space and buried targets from data collected by a ultra-wideband ground penetrating radar(GPR)*** method incorporates the NUFFT algorithm into 3-D phase shift migration to evaluate the inverse Fourier transform more accurately and more efficiently than the conventional migration ***,the nonuniform nature of the wavenumber space required linear interpolation before the regular fast Fourier transform(FFT)could be ***,linear interpolation usually degrades the quality of reconstructed *** NUFFT method mitigates such errors by using high-order spatial-varying *** NUFFT migration method is utilized to reconstruct GPR images collected in laboratory.A plywood sheet in free space and a buried plexiglas chamber are successfully *** results in 3-D visualization demonstrate the outstanding performance of the method to retrieve the geometry of the *** buried landmines are also scanned and reconstructed using this *** the images resolve the features of the objects well,they can be utilized to assist the landmine discrimination.

关键词： Ground-penetrating radar(GPR) migration interpolation phase shift nonuniform fast Fourier transform(NUFFT)

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A long-term in situ calibration system for chemistry analysis of seawater

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第9期11卷 701-708页

作者： Chun-yang TAN Bo JIN Kang DING William E. SEYFRIED jr. Ying ChEN State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China Department of Geology and Geophysics University of Minnesota Minneapolis 55455 USA

An in situ calibration system is a versatile exploration instrument for electrochemical sensors investigating the biochemical properties of the marine environment. The purpose of this paper is to describe the design of an auto-calibrating system for electrochemical (ph) sensors, which permits two-point in situ calibration, suitable for long-term measurement in deep sea aqueous environments. holding multiple sensors, the instrument is designed to perform long-term measurements and in situ calibrations at abyssal depth (up to 4000 m). The instrument is composed of a compact fluid control system which is pressure-equilibrated and designed for deep-sea operation. In situ calibration capability plays a key role in the quality and reproducibility of the data. This paper focuses on methods for extending the lifetime of the instrument, considering the fluidics design, mechanical design, and low-power consumption of the electronics controller. The instrument can last 46 d under normal operating conditions, fulfilling the need for long-term operation. Data concerning ph measured during the KNOX18RR cruise (Mid-Atlantic Ridge, July-August, 2008) illustrate the desirable properties of the instrument. Combined with different electrodes (ph, h2, h2S, etc.), it should be of great utility for the study of deep ocean environments, including water column and diffuse-flow hydrothermal fluids.

关键词： ph Long-term In situ calibration Flow control Low power

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Effects of vertical position on trematode parasitism in larval anurans

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Current Zoology 2019年第6期65卷 657-664页

作者： Jacob R.JONES Camille L.STEENROD John A.MARINO jr. Biology Department Bradley UniversityPeoriaILUSA Department of Geography University of MarylandCollege ParkMDUSA

Spatial distributions of animals can affect interactions with their natural enemies,such as parasites,and thus have important implications for host-parasite *** spatial variation in infection risk has been explored in many systems at the landscape scale,less attention has been paid to spatial structure at smaller ***,we explore a hypothesized relationship between a common spatial variable,vertical position,and risk of parasite infection in a model aquatic system,larval frogs(Rana)and trematode(Digenea)*** position is relevant to this system given evidence that the densities of snail first intermediate hosts,tadpole second intermediate hosts,and trematode infective stages can vary with *** test the effects of depth on infection risk of larval frogs by trematodes,we performed two enclosure experiments,one in the laboratory and one in the field,in which larval frogs in cages just below the water surface or near the bottom of the water column were exposed to *** with near-surface cages,mean infection load(number of cysts)in tadpoles in near-bottom cages was 83%higher after 48-h exposures in the laboratory and 730%higher after 10-day exposures in the *** findings thus indicate that infection risk depends on depth,which may have adaptive significance,as tadpoles have previously been shown to change vertical position in response to parasite *** results motivate future work examining vertical variation in infection risk and may have broader implications for host-parasite dynamics and evolution of host and parasite behavior.

关键词： avoidance behavior cercariae Echinostomatidae host-parasite interactions Rana spatial structure

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