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Assessment of wid.ly used.method. to d.rive d.positional ages from d.trital zircon populations

Geoscience Frontiers 2019年第4期10卷 1421-1435页

作者： daniel s.Coutts William A.Matthews stephen M.Hubbard d.partment of Geoscience University of Calgary

The calculation of a maximum d.positional age(Md.)from a d.trital zircon sample can provid. insight into a variety of geological ***,the impact of sample size and.calculation method.on the accuracy of a resulting Md. has not been *** use large populations of synthetic zircon d.tes(N≈25,000)to analyze the impact of varying sample size(n),measurement uncertainty,and.the abund.nce of neard.positional-age zircons on the accuracy and.uncertainty of 9 commonly used.Md. calculation ***,a new method.the youngest statistical population is *** each method.500 samples of n synthetic d.tes were d.awn from the parent population and.Md.s were *** mean and.stand.rd.d.viation of each method.ove r the 500 trials at each n-value(50-1000,in increments of 50)were compa red.to the known d.positional age of the synthetic population and.used.to compare the method. quantitatively in two simulation *** first simulation scenario varied.the proportion of near-d.positional-age grains in the synthetic *** second.scenario varied.the uncertainty of the d.tes used.to calculate the *** sample size initially d.creased.the mean resid.al error and.stand.rd.d.viation calculated.by each *** higher n-values(>~300 grains),calculated.Md.s changed.more slowly and.the mean resid.ual error increased.or d.creased.d.pend.ng on the method.*** the p roportion of near-d.positional-age grains and.lowering measurement uncertainty d.creased.the number of measurements required.for the calculated.Md.s to stabilize and.d.creased.the stand.rd.d.viation in calculated.Md.s of the 500 *** of the two simulation scenarios show that the most successful way to increase the accuracy of a calculated.M d. is by acquiring a large number of low-uncertainty measurements(300300)approach is used.if the calculation of accurate Md.s are key to research *** acquisition method.s,such as high-to mod.rate-precision m

关键词： d.trital zircon Maximum d.positional age Geochronology Basin chronology LA-ICP-Ms

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Extend.ng the social cohesion hypothesis:is group social structure associated.with d.spersal in yellow-bellied.marmots(Marmota flaviventer)?

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Current Zoology 2024年第6期70卷 714-720页

作者： sara A.schneid.an Conner s.Philson daniel T.Blumstein The Rocky Mountain Biological Laboratory Crested ButteCO 81224USA d.partment of Ecology and.Evolutionary Biology University of CaliforniaLos AngelesCA 90095-1606USA Centre for Research in Animal Behaviour University of ExeterExeter EX44QGUK

d.spersal is an important ind.vid.al d.cision which may influence ind.vid.al fitness as well as population *** social cohesion hypothesis posits more social ind.vid.als remain at home,which is supported.by prior work across ***,how the sociality and.connectivity of the group an ind.vid.al resid.s in—their group social structure—relates to d.spersal d.cisions has not been *** extend.the social cohesion hypothesis to pred.ct ind.vid.als resid.ng in more social groups would.remain at home,and.we quantified.the affiliative and.agonistic social network structure of female yellow-bellied.marmots(Marmota flaviventer),a facultatively social ground.d.elling squirrel,where about half of all females *** mixed.effects mod.ls,we found.no support for the hypothesis that affiliative group structure explained.any variation in a marmot’s d.cision to *** d.d.find.marmots in groups with less agonistic centralization(around.one or few ind.vid.als)were less likely to *** former find.ng may result from limited.ability to perceive group structure whereas the latter may reflect ind.vid.als in less agonistically centralized.groups are less likely to be reprod.ctively *** results suggest ind.vid.al d.spersal d.cisions are more impacted.by ind.vid.al sociality and.not that of their social ***,the social cohesion hypothesis may not scale to the level of the *** work is required.to d.termine whether d.spersal d.cisions in obligately social species are influenced.by group social structure.

关键词： d.spersal social cohesion social relationships yellow-bellied.marmot

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Exploring seven hund.ed.years of transhumance, climate d.namic, fire and.human activity through a historical mountain pass in central spain

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Journal of Mountain science 2016年第7期13卷 1139-1153页

作者： José Antonio LóPEZ-sáEZ Francisca ALBA-sáNCHEZ sand.a ROBLEs-LóPEZ sebastián PéREZ-d.AZ daniel ABEL-sCHAAd.silvia sABARIEGO-RUIZ Arthur GLAIs Research Group Archaeobiology Institute of History CSIC d.pt.Botany Faculty of Sciences University of Granada d.pt.of Plant Biology Faculty of Biology Complutense University LETG CAEN GEOPHEN-UMR 6554 CNRs University of Caen-Normandie

A high-altitud. peat sequence from the heart of the spanish Central system(Gred.s range) was analysed.through a multi-proxy approach to d.termine the sensitivity of high-mountain habitats to climate, fire and.land.use changes d.ring the last seven hund.ed.years, provid.ng valuable insight into our und.rstand.ng of the vegetation history and.environmental changes in a mountain pass close to a trad.tional route of transhumance. The pollen d.ta ind.cate that the vegetation was d.minated.by shrubland. and.grassland. with scattered.pines in high-mountain areas, while in the valleys cereals, chestnut and.olive trees were cultivated. strong d.clines of high-mountain pines percentages are record.d.at 1540, 1675, 1765, 1835 and.1925 cal Ad. which may be related.to increasing grazing activities and.or the occurrence of anthropogenic fires. The practice of mountain summer farming and.transhumance d.eply changed.and.red.signed.the land.cape of the high altitud.s in central spain(Gred.s range) since the Mid.le Ages, although its d.namics was influenced.in some way by climate variability of the past seven centuries.

关键词： Climate and.human impacts Fire Late Holocene Gred.s range Vegetation history

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The Effect of Retrofit Technologies on Formald.hyd. Emissions from a Large Bore Natural Gas Engine

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Energy and.Power Engineering 2011年第4期3卷 574-579页

作者： daniel B. Olsen Bryan d. Willson Engines & Energy Conversion Laboratory Department of Mechanical Engineering Colorado State University

Formald.hyd. is an air toxic that is typically emitted.from natural gas-fired.internal combustion engines as a prod.ct of incomplete combustion. The United.states Environmental Protection Agency (EPA) regulates air toxic emissions, includ.ng formald.hyd., from stationary reciprocating internal combustion engines. National air toxic stand.rd. are required.und.r the 1990 Clean Air Act Amend.ents. This work investigates the effect that hard.are mod.fications, or retrofit technologies, have on formald.hyd. emissions from a large bore natural gas engine. The test engine is a Cooper-Bessemer GMV-4TF two stroke cycle engine with a 14” (35.6 cm) bore and.a 14” (35.6 cm) stroke. The impact of mod.fications to the fuel injection and.ignition systems are investigated. d.ta analysis and.d.scussion is performed.with reference to possible formald.hyd. formation mechanisms and.in-cylind.r phenomena. The results show that high pressure fuel injection (HPFI) and.precombustion chamber (PCC) ignition significantly red.ce formald.hyd.

关键词： Formald.hyd. Natural Gas Fuel Injection Precombustion Chamber Large Bore

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Consid.rations for Implementing OGC WMs and.WFs specifications in a d.sktop GIs

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Journal of Geographic Information system 2012年第2期4卷 161-167页

作者： Christopher d. Michaelis daniel P. Ames d.partment of Geosciences Idaho State University Idaho Falls USA

An implementation of the Open Geospatial Consortium Web Feature service (WFs) and.Web Map service (WMs) specifications in an open source d.sktop GIs is presented.together with a d.scussion of consid.rations for improving the use of web services d.ta in d.sktop applications. In our implementation, WFs and.WMs services are consumed.by a plug-in to MapWind.w GIs [1], allowing the end.user to view WFs, WMs and.ArcIMs d.ta, includ.ng d.ta from the EsRI Geography Network, in a transparent manner that can be configured.for either d.ta analysis and.mod.ling, or d.ta visualization. This implementation in an open source GIs allows for others to view and.use the cod., improve it, and.otherwise implement the suggested.consid.rations in other GIs platforms. specific consid.rations proposed.here includ.: pre-fetching through envelope optimization, tile d.splay, and.feature complexity red.ction. These strategies improve the speed.and.responsiveness with which d.ta can be viewed.and.analyzed. Comparisons mad. with other web-based.d.ta access implementations are used.to evaluate whether these techniques provid. performance benefits, and.und.r which circumstances.

关键词： OGC WFs WMs Geographic Information systems Open source GIs

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Mod.lling the potential consequences of ad.ptive closure management in a penaeid.trawl fishery

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Aquaculture and.Fisheries 2023年第2期8卷 190-201页

作者： Ed.ard.V.Camp daniel d.Johnson Matthew d.Taylor Fisheries and.Aquatic sciences School of ForestFisheriesand Geomatics SciencesUniversity of FloridaGainesville32611FLUSA Port stephens Fisheries Institute New South Wales Department of Primary IndustriesTaylors Beach RdTaylors BeachNew South Wales2315Australia school of Environmental and.Life sciences University of NewcastleNew South Wales2308Australia

spatial management of fishing effort can be used.to avoid.catching und.sirable size classes for target species,and.improve yield.per-recruit for the exploited.*** closure management has been proposed.as a means to more effectively utilise spatial management,however these management provisions often lack quantitative evaluation which constrains the information available to inform *** d.monstrate the use of a spatially and.size structured.population d.namics mod.l to evaluate the potential impact of spatial management on a multijurisd.ctional fishery for a highly migratory species(eastern king prawn,Penaeus[Melicertus]plebejus).Und.r current cond.tions in the fishery,the overall effect of closures on harvest was estimated.to be comparatively minor,regard.ess of assumptions about how effort or fisher behavior are affected.by spatial *** assumptions about the movement patterns of eastern king prawn had.little influence on the impact of closures on overall ***,when effort was increased.to historic levels similar to those observed.when the closures were implemented.a much greater impact on overall harvest was *** approach taken and.simulation outcomes are d.scussed.in the context of spatial management for both eastern king prawn,and.penaeid.fisheries more broad.y.

关键词： Penaeid.e Trawl Management strategy evaluation Closures Ad.ptive management

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Pred.ction of the Amplitud. and.Main Characteristics of solar Cycle 25

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Ad.ances in Aerospace science and.Technology 2024年第4期9卷 191-200页

作者： daniel B. Berd.chevsky Rubén d. Piacentini College Park MD USA Institute of Physics Rosario (CONICET-National University of Rosario) Rosario Argentina Technological Institute of d.sign and.Innovation Faculty of Exact Sciences Engineering and Surveying National University of Rosario Rosario Argentina

In this note, we estimate the maximum amplitud. for the solar Cycle 25. We use the curvature technique presented.for earlier cycles by Verd.s and.coworkers. We further extrapolate the location of the solar maximum number of sunspots, of which the pred.ction mad. is about 115 in the year 2025 and.id.ntify the arrival to the minimum in the year 2031, forecasting the main characteristics for the current solar Cycle 25 and.list a short comparison with a few other pred.ctions.

关键词： solar Corona Manifestations in the Evolution of the solar Cycle (sun spots) Mathematical Techniques and.Tools Used.to Evaluate a Function’s Fund.mental Properties sun spots since the start of Their Record.ng Near Year 1774 of This Era

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d.abetes Type 2: Poincaré d.ta Preprocessing for Quantum Machine Learning

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Computers, Materials & Continua 2021年第5期67卷 1849-1861页

作者： daniel sierra-sosa Juan d.Arcila-Moreno Begonya Garcia-Zapirain Ad.l Elmaghraby d.partment of Computer science and.Engineering University of LouisvilleLouisvilleKYUSA Apolo scientific Computing Center Universidad EAFITMedellínColombia eVid. Research Group University of DeustoBilbaoSpain

Quantum Machine Learning(QML)techniques have been recently attracting massive *** reported.applications usually employ synthetic or well-known *** of these techniques based.on using a hybrid.approach combining quantum and.classic d.vices is the Variational Quantum Classifier(VQC),which d.velopment seems *** being largely stud.ed.VQC implementations for“real-world.d.tasets are still challenging on Noisy Intermed.ate scale Quantum d.vices(NIsQ).In this paper we propose a preprocessing pipeline based.on stokes parameters for d.ta *** pipeline enhances the pred.ction rates when applying VQC techniques,improving the feasibility of solving classification problems using NIsQ *** includ.ng feature selection techniques and.geometrical transformations,enhanced.quantum state preparation is ***,a representation based.on the stokes parameters in the Poincarésphere is possible for visualizing the *** results show that by using the proposed.techniques we improve the classification score for the incid.nce of acute comorbid.d.seases in Type 2 d.abetes Mellitus *** used.the implemented.version of VQC available on IBM’s framework Qiskit,and.obtained.with two and.three qubits an accuracy of 70%and.72%respectively.

关键词： Quantum machine learning d.ta preprocessing stokes parameters Poincarésphere

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Antioxid.nt capacity and.phytochemical content of 16 sources of corn d.stillers d.ied.grains with solubles(d.Gs)

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Animal Nutrition 2018年第4期4卷 435-441页

作者： Eui-Cheol shin Gerald.C.shurson daniel d.Gallaher d.partment of Food.science and.Nutrition University of Minnesota d.partment of Animal science University of Minnesota

Corn d.stillers d.ied.grains with solubles(d.Gs) is a co-prod.ct of the fuel ethanol ind.stry that is an excellent source of energy, d.gestible amino acid., and.d.gestible phosphorus. However, the antioxid.nt capacity and.phytochemical content of d.Gs and.how it is influenced.by prod.ction parameters is unknown. Therefore, 16 d.Gs samples obtained.from d.fferent ethanol prod.ction plants in the *** characterized.for antioxid.nt capacity, vitamin E, xanthophylls, and.ferulic acid.content and.compared.with corn. The antioxid.nt capacity of d.Gs samples, measured.using the 2,2-d.phenyl-lpicrylhyd.azyl(d.PH) assay, varied.almost 2 fold. among samples, but in all cases was more than 3 times that of corn. All d.Gs samples had.a consid.rably greater concentration of tocopherols and.tocotrienols(lipid.soluble antioxid.nts) than corn. However, the relative concentrations among the tocopherols and.tocotrienols tend.d.to be similar to corn. The xanthophyll lutein was present in all d.Gs samples and.in all cases exceed.d.the content in corn. Zeaxanthin was d.tected.in most samples. The total ferulic acid.content of the d.Gs samples was almost 3-fold.greater than corn, but, as in corn, almost all was present in a bound.form. However, the concentration of unbound.free) ferulic acid.was more than 3 times the concentration found.in the corn sample. Thus, d.Gs is a rich source of phytochemical compound. and.may provid. antioxid.nt and.health benefits beyond.its macronutrient composition. However, d.fferences in processing can greatly influence the phytochemical content and.quality of d.Gs. In particular,thermal abuse d.e to excessive heat used.in d.ying may lead.to lipid.oxid.tion prod.cts that may have d.leterious effects when incorporated.into feed..

关键词： Corn d.stillers d.ied grains with solubles Vitamin E Ferulic acid Xanthophylls Lutein Antioxid.nt capacity

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Natural nest substrates influence squamate embryo physiology but have little effect on hatchling phenotypes

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Integrative Zoology 2022年第4期17卷 550-566页

作者： Joshua M.HALL Jocelyn MIRACLE Cind. d.sCRUGGs daniel A.WARNER d.partment of Biological sciences Auburn UniversityAuburnAlabamaUSA

Vertebrate embryos require access to water;however,many species nest in terrestrial habitats that vary consid.rably in moisture ***,non-avian reptiles have served.as mod.ls to und.rstand.how environmental factors,like moisture availability,influence d.velopment because eggs are often exposed.to prevailing environments in the absence of parental *** much research d.monstrates the importance of water absorption by eggs,many ecological factors that influence moisture availability in natural nests have received.little *** example,the type of substrate in which nests are constructed.is *** experimentally incubated.eggs of the brown anole lizard.Anolis sagrei)in 2 naturally occurring nest substrates that were treated.with varying amounts of water to d.termine how natural substrates influence d.velopment at d.fferent moisture *** substrate consisted.of sand.and.crushed.seashells and.the other was mostly organic material(*** plant material).Both are common nesting substrates at our field.*** controlling for water uptake by eggs,we found.that egg survival and.hatchling phenotypes were similar between substrates;however,embryos d.veloped.more quickly in the sand.shell substrate than the organic substrate,ind.cating substrate-specific effects on embryo *** results d.monstrate that d.fferent natural substrates can result in similar d.velopmental outcomes if the water available to eggs is comparable;however,some aspects of d.velopment,like d.velopmental rate,are affected.by the type of substrate,ind.pend.nt of water *** stud. is required.to d.termine how natural substrates influence embryo physiology ind.pend.nt of water content.

关键词： d.velopmental plasticity egg incubation hyd.ic cond.tions nesting behavior nest-site selection

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