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Effects of a regenerating matrix on the survival of birds in tropical forest fragments

Avian Research 2020年第1期11卷 16-24页

作者： jared D.Wolfe Philip C.Stouffer richard O.Bierregaard jr David A.Luther Thomas E.Lovejoy College of Forest Resources and Environmental Science Michigan Technological UniversityHoughtonMI 49931USA Biological Dynamics of Forest Fragments Project Instituto Nacional de Pesquisas da AmazoiaManaus 69011Brazil College of Renewable Natural Resources Louisiana State University AgCenterLouisiana State UniversityBaton RougeLA 70803USA Biology Department George Mason University4400 University Drive MS3EFairfaxVA 22030USA

Background: Vast areas of lowland neotropical forest have regenerated after initially being cleared for agricultural purposes. The ecological value of regenerating second growth to forest-dwelling birds may largely depend on the age of the forest, associated vegetative structure, and when it is capable of sustaining avian demographics similar to those found in pristine ***: To determine the influence of second growth age on bird demography, we estimated the annual survival of six central Amazonian bird species residing in pristine forest, a single 100 and a single 10 ha forest fragment, taking into consideration age of the surrounding matrix(i.e. regenerating forest adjacent to each fragment) as an explanatory ***: Study species exhibited three responses: arboreal, flocking and ant-following insectivores(Willisornis poecilinotus, Thamnomanes ardesiacus and Pithys albifrons) showed declines in survival associated with fragmentation followed by an increase in survival after 5 years of matrix regeneration. Conversely, Percnostola rufifrons, a gap-specialist, showed elevated survival in response to fragmentation followed by a decline after 5 years of regeneration. Lastly, facultative flocking and frugivore species(Glyphorynchus spirurus and Dixiphia pipra, respectively) showed no response to adjacent clearing and subsequent ***: Our results in association with previous studies confirm that the value of regenerating forest surrounding habitat patches is dependent on two factors: ecological guild of the species in question and second growth age. Given the rapid increase in survival following succession, we suggest that the ecological value of young tropical forest should not be based solely on a contemporary snapshot, but rather, on the future value of mature second growth as well.

关键词： Amazon fragmentation Brazil Matrix Second growth Survival Tropical bird

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Impact on Soil Organic C and Total Soil N from Cool- and Warm-Season Legumes Used in a Green Manure-Forage Cropping System

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Agricultural Sciences 2024年第3期15卷 333-357页

作者： Clark B. Neely Francis M. Rouquette jr. Cristine L.S. Morgan Frank M. Hons William L. Rooney Gerald R. Smith Department of Soil and Crop Science Washington State University Pullman WA USA Texas A&M AgriLife Research Overton TX USA Chief Scientific Officer Soil Health Institute Morrisville NC USA Department of Soil and Crop Science Texas A&M University College Station TX USA

Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their seasonal biomass production can be managed to complement forage grasses. Our research objectives were to evaluate both warm- and cool-season annual forage legumes as green manure for biomass, N content, ability to enhance soil organic carbon (SOC) and soil N, and impact on post season forage grass crops. Nine warm-season forage legumes (WSL) were spring planted and incorporated as green manure in the fall. Forage rye (Secale cereale L.) was planted following the incorporation of WSL treatments. Eight cool-season forage legumes (CSL) were fall planted in previously fallow plots and incorporated as green manure in late spring. Sorghum-sudangrass (Sorghum bicolor x Sorghum bicolor var. sudanense) was planted over all treatments in early summer after forage rye harvest and incorporation of CSL treatments. Sorghum-sudangrass was harvested in june, August and September, and treatments were evaluated for dry matter and N concentration. Soil cores were taken from each plot, split into depths of 0 to 15, 15 to 30 and 30 to 60 cm, and soil C and N were measured using combustion analysis. Nylon mesh bags containing plant samples were buried at 15 cm and used to evaluate decomposition rate of above ground legume biomass, including change in C and N concentrations. Mungbean (Vigna radiata L. [Wilczek]) had the highest shoot biomass yield (6.24 t DM ha-1) and contributed the most total N (167 kg∙ha-1) and total C (3043 kg∙ha-1) of the WSL tested. Decomposition rate of WSL biomass was rapid in the first 10 weeks and very slow afterward. Winter pea (Pisum sativum L. spp. sativum), arrow leaf clover (Trifolium vesiculosum Savi.), and crimson clover (Trifolium incarnatum L.) were the most productive CSL in this trial. Austrian winter pea

关键词： Annual Legumes Soil N Soil Organic C Green Manure Deer Browse Forage Cropping Systems

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Analyses of plasma reactive sputter deposition of CN_x films by OES

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Chinese Science Bulletin 1997年第21期42卷 1792-1795页

作者： Zhao, j Kang, N Wang, jG Wang, RY Xu, jr Chinese Acad Sci Inst Phys Lab Opt Phys Beijing 100080 Peoples R China

OPTICAL emission spectroscopy (OES) is generally used in diagnosis on the various plasma filmdeposition processes to understand the mechanism of film growth. However, although the de-position precursors have been predicted such as CN radicals and nitrogen atoms, up tonow no diagnostic work on CN_x film deposition process, as we know, has been reported *** previously reported research work, the properties of CN_x film display some obvious dif-ference. For instance, some CN_x films have extreme mechanical properties with hardness

关键词： carbon nitride fiim optical emission spectras optical gap.

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Paleoecological Response of Corals to the End-Triassic Mass Extinction： An Integrational Analysis

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journal of Earth Science 2018年第4期29卷 879-885页

作者： George D Stanley jr Hannah M E Shepherd Autumn j Robinson University of Montana Paleontology Center Missoula MT 59812 USA

The end-Triassic （also Triassic-jurassic） mass extinction severely affected life on planet Earth 200 million years ago. Paleoclimate change triggered by the volcanic eruptions of the Central Atlantic Magmatic Province （CAMP） caused a great loss of marine biodiversity, among which 96% coral genera were get lost. However, there is precious little detail on the paleoecology and growth forms lost between the latest Triassic extinction and the Early jurassic recovery. Here a new pilot study was conducted by analyzing corallite integration levels among corals from the latest Triassic and Early jurassic times. Integration levels in corals from the Late Triassic and Early jurassic were determined through both the Paleobiology Database as well as from a comprehensive museum collection of fossil corals. Results suggest that in addition to a major loss of diversity following the end-Triassic mass extinction, there also was a significant loss of highly integrated corals as clearly evidenced by the coral data from the Early jurassic. This confirms our hypothesis of paleoecological selectivity for corals following the end-Triassic mass extinction. This study highlights the importance of assigning sim- ple to advanced paleoecological characters with integration levels, which opens a useful approach to understanding of mass extinction and the dynamics of the recovery.

关键词： coral loss integration level end-Triassic mass extinction paleoecology

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The Electrochemical Investigation of MEH-PPV in Ionic Liquid

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Chinese Chemical Letters 2000年第10期11卷 919-920页

作者： Yang, CH He, GF Zheng, jr Qiao, j Li, YF Chinese Acad Sci Inst Chem Ctr Mol Sci Lab Organ Solids Beijing 100080 Peoples R China

The electrochemical properties of MEH-PPV were: studied in ionic liquid([bmim](+)[PF6](-)) by cyclic voltammetry, chronoamperometry and AC impedance measurements. Both p- and n-doping of MEH-PPV were observed in the cyclic voltammograms, The chronoamperometric and AC impedance results indicate that the p-doping of MEH-PPV was controlled by the linear diffusion of counterions.

关键词： MEH-PPV electrochemistry ionic liquid

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High-performance warm white LED based on thermally stable all inorganic perovskite quantum dots

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Opto-Electronic Advances 2023年第3期6卷 84-87页

作者： jr-Hau He Department of Materials Science and Engineering City University of Hong KongHong Kong 999077China

All inorganic CsPbBr_(3) quantum dots(QDs)are regarded as excellent candidates for next-generation emitters due to their high photoluminescence quantum yield(PLQY)and defect ***,the poor stability and degraded luminescent performance may impede their further commercialization because of the separation of conventional ligands from the QDs ***,Zang replaced the regular oleic acid with 2-hexyl-decanoic acid(DA),which possesses higher binding energy on the QDs surfaces,to act as ligands of QDs,exhibiting PLQY of 96%and excellent stabilities against ethanol and *** with DA-modified CsPbBr_(3) QDs achieved improved thermal stability,a color rendering index of 93,a power efficiency of 64.8 lm/W and a properly correlated color temperature value of 3018 K,implying their prominent applications in solid-state lighting and displays.

关键词： inorganic quantum performance

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Legume Green Manure and Intercropping for High Biomass Sorghum Production

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Agricultural Sciences 2024年第6期15卷 605-621页

作者： Clark B. Neely Francis M. Rouquette jr. Cristine L. S. Morgan Frank M. Hons William L. Rooney Gerald R. Smith Department of Soil and Crop Science Washington State University Pullman WA USA Texas A&M AgriLife Research Overton TX USA Soil Health Institute Morrisville NC USA Department of Soil and Crop Science Texas A&M University College Station TX USA

Before the advent of cheap, synthetic fertilizers, legumes were commonly used as green manure crops for their ability to fix atmospheric nitrogen (N). A three-year study at Overton, TX examined legume integration into high-biomass sorghum (Sorghum bicolor L.) production systems on a Lilbert loamy fine sand recently cultivated after a fertilized bermudagrass [Cynodon dactylon (L.) Pers.] pasture. In this split-split plot design, ‘Dixie’ crimson clover (Trifolium incarnatum L.) and ‘Iron and Clay’ cowpea (Vigna unguiculata L.) were integrated into a high-biomass sorghum production system to evaluate impacts on N concentration, C concentration, and yield of high-biomass sorghum and their impacts on soil total N and soil organic carbon (SOC). Main plots were split into crimson clover green manure (CLGM) and winter fallow (FALL) followed by three sub-plots split into warm-season crop rotations: cowpea green manure (CPGM), cowpea-sorghum intercrop (CPSR), and sorghum monocrop (SORG). Three N fertilizer treatments (0, 45, 90 kg N∙ha−1) were randomized and applied as sub-sub plots. The CLGM increased (P sorghum biomass yield (16.5 t DM∙ha−1) 28% in year three but had no effect in the first two years. The CPSR treatment reduced sorghum yield up to 62% compared to SORG;whereas CPGM increased sorghum yield 56% and 18% the two years following cowpea incorporation. Rate of N fertilizer had no effect on sorghum biomass yield. Decrease in SOC and soil N over time indicated mineralization of organic N and may explain why no N fertilizer response was observed in sorghum biomass yield. Cowpea showed strong potential as a green manure crop but proved to be too competitive for successful intercropping in high-biomass sorghum production systems.

关键词： High-Biomass Sorghum Legumes Green Manure Intercrop Cowpea Crimson Clover Soil Organic Carbon Soil Nitrogen

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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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Study of Solidification Shrinkage of Ductile Iron in Dry Sand Molds

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journal of Materials Science & Technology 1999年第3期15卷 245-250页

作者： Li, jr Liu, BC Beijing Inst Aeronaut mat Beijing 100095 Peoples R China Tsing Hua Univ Dept Engn Mech Beijing 100084 Peoples R China

The effects of metallurgical and processing parameters on the formation of solidification shrinkage in ductile iron have been studied, considering the parameters of carbon equivalent, inoculation, casting modulus and pouring temperature within specific ranges of these variables. Based on the orthogonal experiments, the metallurgical and processing parameters of the minimum casting shrinkage and the maximum casting shrinkage were obtained, and the effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in ductile iron castings were discussed. A regression equation relating these variables to the formation of shrinkage was derived based upon the orthogonal experiments conducted.

关键词： Nodular iron

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Cherishing the Memory of My Father——In Commemoration of 10th Anniversary of Death of richard Frey

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Voice of Friendship 2015年第1期 46-48页

作者： richard Frey jr.

(Continued from the previous issue)My father,asa Chinesere volutionary of Austri and ecent,wasself-disciplined and low-key all his *** a 65-year revolutionary career in China—his second homeland—he witnessed the War of Resistance Against japanese Aggression,War of Liberation,New China’s construction and development,the"cultural revolution"and reform and opening up;he underwent all kinds of hardships and suffered from *** unfairly treated and

关键词： revolution witnessed suffered father career japane

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