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Egg rejection behavior does not explain the lack of cowbird parasitism on an eastern North American population of Red-winged Blackbirds

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Avian Research 2019年第4期10卷 431-440页

作者： Justin J.Reel todd J.Underwood department of Biology Kutztown University

Background:Red-winged Blackbirds(Agelaius phoeniceus),hereafter red-wings,are much less frequently parasitized by Brown-headed Cowbirds(Molothrus ater)in eastern North America than in central North America and had not been recorded as hosts in our study area in southeastern *** hosts of Old World cuckoos(Cuculidae)often show geographic variation in egg rejection behavior,cowbird hosts typically exhibit uniform responses of all acceptance or all rejection of cowbird ***,geographic variation in cowbird parasitism frequencies might reflect a different behavioral response to parasitism by hosts where only some populations reject *** this study,we tested whether egg rejection behavior may explain the lack of parasitism observed in our eastern red-wing population,which may provide insight into low parasitism levels across eastern North ***:We parasitized red-wing nests with model cowbird eggs to determine their response to *** were tested across three nest stages and compared to control nests with no *** rejection differed significantly by stage,we compared responses separately for each nest *** also monitored other songbird nests to identify parasitism frequencies on all potential ***:Red-wings showed significantly more rejections during the building stage,but not for the laying and incubation *** during nest building involved mostly egg burials,which likely represent a continuation of the nest building process rather than true rejection of the cowbird *** these responses,red-wings rejected 15%of cowbird eggs,which is similar to rejection levels from other studies and *** overall parasitism frequency on 11 species surveyed in our study area was only 7.4%.Conclusions:Egg rejection behavior does not explain the lack of parasitism on red-wings in our eastern ***,we suggest that cowbird preference for other hosts and the low abu

关键词： Brood parasitism Brown-headed Cowbird Egg rejection Geographic variation Red-winged Blackbird

Multi-year MOdIs active fire type classification over the Brazilian Tropical Moist Forest Biome

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International Journal of digital Earth 2017年第1期10卷 54-84页

作者： d.P.Roy s.s.Kumar Geospatial sciences Center of Excellence South Dakota State UniversityBrookingsSDUSA

The Brazilian Tropical Moist Forest Biome(BTMFB)spans almost 4 million km^(2) and is subject to extensive annual fires that have been categorized into deforestation,maintenance,and forest fire *** on fire types is important as they have different atmospheric emissions and ecological impacts.A supervised classification methodology is presented to classify the fire type of MOderate resolution Imaging spectroradiometer(MOdIs)active fire detections using training data defined by consideration of Brazilian government forest monitoring program annual land cover maps,and using predictor variables concerned with fuel flammability,fuel load,fire behavior,fire seasonality,fire annual frequency,proximity to surface transportation,and local *** fire seasonality,local temperature,and fuel flammability were the most influential on the *** fire type results for all 1.6 million MOdIs Terra and Aqua BTMFB active fire detections over eight years(2003–2010)are presented with an overall fire type classification accuracy of 90.9%(kappa 0.824).The fire type user’s and producer’s classification accuracies were respectively 92.4%and 94.4%(maintenance fires),88.4%and 87.5%(forest fires),and,88.7%and 75.0%(deforestation fires).The spatial and temporal distribution of the classified fire types are presented and are similar to patterns reported in the available recent literature.

关键词： Earth observation land cover remote sensing

Thermal inertia at the MsL and Insight mission sites on Mars

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Earth and Planetary Physics 2022年第1期6卷 18-27页

作者： d.singh s.Uttam Centre of studies in Resources Engineering Indian Institute of Technology BombayMumbaiIndia Physical Research Laboratory AhmedabadIndia

For planetary surface materials,thermal inertia is the critical property that governs the surface’s daily thermal response and controls diurnal and seasonal surface temperature *** we use the ground measurements made by the MsL Curiosity rover and the Insight lander to determine the thermal inertia of two sites on *** study compares the variation of thermal inertia during and after the Large dust storm(Lds)of Martian Year(MY)*** determine surface thermal inertia,we derive a simple approximation(using energy balance),which utilizes surface albedo,surface energy flux,and diurnal change in the surface *** average thermal inertia in MY34 is about 39.2%,3.7%,and 3.4%higher than MY35 average thermal inertia for the MsL,Insight(FOV1),and Insight(FOV2),***,the thermal inertia at the Insight(FOV1)is consistently lower by about 20 J·m^(-2)·s^(-1/2)·K^(-1) than the Insight(FOV2)site for all scenarios,indicating variation in the region’s surface *** best-fit surface albedo in MY34(determined using the KRC model)are about 0.08,0.05,and 0.03 higher than MY35 surface albedo for the MsL,Insight(FOV1),and Insight(FOV2),*** increase in both surface albedo and thermal inertia during the Lds indicates that the underlying surface is both more thermally resistant and more reflective than the overlying loose dust.

关键词： Mars Mars surface thermal inertia dust storm Mars climate

EFFECT OF sEN dEsIGN ON sURFACE FLUCTUATION ANd sOLIdIFYING sHELL IN sLAB MOLd ANd ITs OPTIMIZATION

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Acta Metallurgica sinica(English Letters) 2008年第5期21卷 341-350页

作者： d.F. Wu s.s. Cheng school of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

Turbulent flow and heat transfer coupled with solidification in slab continuous casting mold was studied by numerical simulation method. Volume of fluid （VOF） model is used to solve steel-air two-phase flow problem and enthalpy-porosity scheme is introduced to solve the fluid flow problem involving solidification. Contributions of various nozzle port angles and port widths and heights on the free surface fluctuation and the thickness of solidifying shell in slab mold were particularly investigated, based on which the structure of submerged entry nozzle was optimized. Flow inside the common nozzle port cannot fill the entire outlet area, having a recirculation in the upper portion of the port, which is enlarged for the nozzle port with both larger height and width. Results show that the flow in mold cavity is mainly controlled by the nozzle port angle. The increase of the angle of upper face of the port to shape a roughly streamlined inner-wall improves the effective area fraction of the nozzle, resulting in less jet impingement, weaker free surface turbulence and thicker solidifying steel shell.

关键词： slab continuous casting submerged entry nozzle Optimization Numerical simulation

dNA Barcoding and systematic Review of Minervaryan Frogs(dicroglossidae:Minervarya) of Peninsular India:Resolution of a Taxonomic Conundrum with description of a New species

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Asian Herpetological Research 2021年第4期12卷 345-370页

作者： sonali GARG s.d.BIJU systematics Lab Department of Environmental StudiesUniversity of Delhi

The genus Minervarya is among the most widely distributed,commonly occurring,and taxonomically confusing groups of dicroglossid frogs in *** studies have provided evidence that this genus contains complexes of morphologically conserved but genetically divergent taxa—some widely distributed across south and southeast Asia,and many particularly restricted to the Western Ghats region of the Indian Peninsula—posing several challenges in resolving long-standing taxonomic ***,we present a systematic review of minervaryan species found in Peninsular India,based on extensive dNA barcoding with nearly 400 samples from the entire range of the genus,including 277 new samples and topotypic material for most available names from the study area,combined with detailed morphological *** a result,we recognise 18 species in Peninsular India,including a new species described herein as Minervarya pentali *** to the comprehensive nature of the study,including comparisons with all available types,certain long-standing taxonomic uncertainties on the status of ten previously known taxa are resolved Rana(Tomopterna)parambikulamana Rao,1937(=Minervarya parambikulamana),Rana(Hylorana)sauriceps Rao,1937(=Minervarya sauriceps),and Fejervarya kudremukhensis Kuramoto,Joshy,Kurabayashi,and sumida,2008"2007"(=Minervarya kudremukhensis),are considered as junior subjective synonyms of Rana(Rana)limnocharis mysorensis Rao,1922(=Minervarya mysorensis);Nyctibatrachus sanctipdustris *** Rao,1920(=Minervarya modesta)is proposed to be a synonym of Rana limnocharis syhadrensis Annandale,1919(=Minervarya syhadrensis);while Rana murthii Pillai,1979(=Minervarya murthii)and Fejervarya mudduraja Kuramoto,Joshy,Kurabayashi,and sumida,2008"2007"(=Minervarya mudduraja)are considered as junior subjective synonyms of Rana nilagirica Jerdon,1853(=Minervarya nilagirica).At the same time,Rana brevipalmata Peters,1871(=Minervarya brevipalmata),previously known only from its ori

关键词： amphibia distribution Fejervarya integrative taxonomy Minervarya pentali sp.nov. morphology species groups Western Ghats Biodiversity Hotspot

Global operational land imager Landsat-8 reflectance-based active fire detection algorithm

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International Journal of digital Earth 2018年第2期11卷 154-178页

作者： s.s.Kumar d.P.Roy Plant and Environmental sciences New Mexico State UniversityLas CrucesNMUSA Geospatial sciences Center of Excellence South Dakota State UniversityBrookingsSDUSA

A global operational land imager(GOLI)Landsat-8 daytime active fire detection algorithm is *** utilizes established contextual active fire detection approaches but takes advantage of the significant increase in fire reflectance in Landsat-8 band 7(2.20μm)relative to band 4(0.66μm).The detection thresholds are fixed and based on a statistical examination of 39 million non-burning Landsat-8 ***-temporal tests based on band 7 reflectance and relative changes in normalized difference vegetation index in the previous six months are used to reduce commissions *** probabilities of active fire detection for the GOLI and two recent Landsat-8 active fire detection algorithms are simulated to provide insights into their performance with respect to the fire size and *** algorithms are applied to 11 Landsat-8 images that encompass a range of burning conditions and *** and omission errors are assessed by visual interpretation of detected active fire locations and by examination of the Landsat-8 images and higher spatial resolution Google Earth *** GOLI algorithm has lower omission and comparable commission errors than the recent Landsat-8 active fire detection *** GOLI algorithm has demonstrable potential for global application and is suitable for implementation with other Landsat-like reflective wavelength sensors.

关键词： Earth observation remote sensing visible/infrared remote sensing

Thermal stress relaxation in shot peened and laser peened nickel-based superalloy

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Journal of Materials science & Technology 2020年第24期59卷 100-106页

作者： K.s.Chin s.Idapalapati d.T.Ardi school of Mechanical and Aerospace Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore Advanced Remanufacturing and Technology Centre 3 CleanTech LoopCleanTech Two#01/01Singapore 637143Singapore

The effects of cold work produced by peening processes in residual stress relaxation under elevated temperatures were *** types of peening processes namely shot peening and laser peening were used to generate different amount of cold work and residual stresses in the *** of residual stress induced by cold working were carried out using X-ray diffraction coupled with electrochemical polishing method to measure the variation of residual stress with *** stresses in shot peened samples were observed to relax more rapidly than that of laser peened ones when subjected to thermal *** data collected from the experimental investigation was then used to build a correlation function to model the effects of cold work on residual stress relaxation.A parameter describing cold work’s contribution to stress relaxation is introduced into the well-known Zener-WertAvrami(ZWA)*** model was validated against experimental measurements and showed good agreement in both shot peened and laser peened samples.

关键词： Residual stress Cold work surface treatment Nickel-based superalloys

Effect of natural and synthetic antioxidants on oxidative stability of FAMEs obtained from hevea brasiliensis

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Journal of Energy Chemistry 2013年第6期22卷 935-941页

作者： s.Nivetha d.Vetha Roy department of Chemistry and Research Centre Scott Christian College

Biodiesel(fatty acid alkyl esters),an alternate to fossil fuel,has the tendency of autoxidation and hence requires antioxidants for long term *** influence of synthetic and natural antioxidants on the oxidative stability was analysed for fresh FAMEs(fatty acid methyl esters)obtained from hevea brasiliensis at 140 *** activity was observed for synthetic antioxidants following the order of GA>BHT>dTBP>Q>GT-M>PH-M>GT-C,whereas the oxidative stability of stored FAMEs samples measured at 110 C reveals a nearly inverse *** stability was tested for the FAMEs obtained from hevea brasiliensis stored at 30 C,after addition of synthetic and natural antioxidants—butylated hydroxytoluene(BHT),2,6-di-tert-butylphenol(dTBP),quercetin(Q),gallic acid(GA),methanol extracts from green tea(GTM),pomegranate hull(PH-M),and chloroform extract of green tea(GT-C).Antioxidant activities above 1500 ppm was in the order of dTBP>BHT>GA>GT-C>GT-M>Q>*** antioxidants have been found more efficient to improve the storage stability of FAMEs obtained from hevea *** in particular has the highest protection factor.

关键词： hevea brasiliensis fatty acid methyl esters oxidative stability storage stability antioxidants

Influence of Grain size and Texture on the Yield Asymmetry of Mg-3Al-1Zn Alloy

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Journal of Materials science & Technology 2011年第1期27卷 29-34页

作者： s.M.Yin C.H.Wang Y.d.diao s.d.Wu s.X.Li shenyang University of Chemical Technology Shenyang 110142China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The yield asymmetry between compression and tension of magnesium alloy Mg-3Al-1Zn（AZ31） with different grain sizes and textures has been studied by tensile and compressive testing of as-cast,as-extruded and equal channel angular pressed（ECAPed） *** significant yield asymmetry（the ratio of yield strength between compression and tension σyc/σyt is ～0.44） was found in as-extruded specimens and the corresponding microstructure evolution during deformation revealed that {10 ˉ 12} tensile twinning is the underlying reason for the large yield *** texture and grain size are influential factors for large yield *** separate contributions of grain size and texture on yield asymmetry were investigated.

关键词： Magnesium alloys Yield asymmetry Texture Grain size Equal channel angular pressing(ECAP)