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Assessing the Suitabil.ty of the Worl.Cl.m Dataset for Ecol.gical.Studies in Southern Kenya

j.urnal.of Geographic Information System 2018年第6期10卷 643-658页

作者： tim j. l. wango Dougl.s Musiega Charl.s N. Mundia Department of Geomatic Engineering & Geospatial.Information Systems Jomo Kenyatta University of Agriculture and Technology Juja Kenya Department of Geomatics and Geospatial.Information Systems Dedan Kimathi University Nyeri Kenya

There have been numerous efforts to generate freel. avail.bl. cl.matic datasets for use in species distribution model., the most popul.r being the gl.bal.cl.matic dataset known as Worl.Cl.m. The avail.bil.ty of such datasets is inval.abl. to scientists as many studies are performed in remote areas where no weather stations are found. However, many users do not critical.y assess the suitabil.ty of these datasets for their appl.cations, and errors associated with gl.bal.datasets are often assumed to be negl.gibl.. Understanding what a cl.mate dataset can or cannot del.ver requires the user to have a working knowl.dge of what the basic spatial.cl.mate-forcing factors are at the scal. of his/her study, and to have a good understanding of the uncertainty in the dataset. In geographic studies, uncertainty is often described by the degree of error (uncertainty), or degree of accuracy (certainty) in data, and thematic uncertainty refers to the uncertainty in measures made for each variabl., whereas temporal.uncertainty refers to the uncertainty in time period represented by each variabl.. Here, we used cl.matic data from weather stations to investigate the cl.mate-forcing factors in southern Kenya, and then used this weather station data to investigate the uncertainty in the Worl.Cl.m dataset. Resul.s indicated that the nineteen core Worl.cl.m variabl.s, known as biocl.matic variabl.s, accuratel. depicted the l.cal.variations in cl.mate in the study area. However, whereas the monthl. and seasonal.temperature variabl.s represented the same time period in different l.cations, the same was not true for the monthl. and seasonal.precipitation variabl.s. The onset of rains is a key biol.gical.indicator, and scientists studying phenomena tied to the onset of rains need to keep in mind the temporal.variations represented in the Worl.Cl.m dataset.

关键词： Worl.Cl.m Biocl.matic Variabl.s Thematic Uncertainty Temporal Uncertainty

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Seed Germination of Five Poa Species at Negative Water Potential.

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American j.urnal.of Pl.nt Sciences 2016年第3期7卷 601-611页

作者： tim l. Springer j.son j. Gol.man Southern Pl.ins Range Research Station USDA-Agricultural Research Service Woodward OK USA

Under fiel. conditions water is often inadequate for satisfactory seed germination. An experiment was conducted to determine the effects of simul.ted dry conditions on germination and seedl.ng growth of five bl.egrass (Poa) species, incl.ding: Texas, P. arachnifera Torr.;annual. P. annua l.;mutton, P. fendl.riana Vasey;Kentucky, P. pratensis l., and Sandberg, P. secunda j. Presl. bl.egrasses. Fifty-seed sampl.s of each species were germinated at water potential. of -1.6, -0.8, -0.4, -0.2, and 0 MPa for a 42-d period. Annual.and Sandberg bl.egrass tol.rated moisture stress at germination better than the other species, requiring 14 d to reach 40% germination in water of -0.8 MPa potential. Kentucky bl.egrass required 21 d to reach 40% germination under simil.r conditions. Mutton and Texas bl.egrass were the l.ast tol.rant of l.w water potential., requiring 42 d to reach 20% germination. Sel.ction for increased seed germination at l.w water potential. shoul. be possibl. in Poa species assuming the trait has moderate heritabil.ty.

关键词： Negative Water Potential Poa Seed Germination

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Non-invasive Angiographic-based Fractional.Fl.w Reserve:Technical.Devel.pment,Cl.nical.Impl.cations,and Future Perspectives

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当代医学科学(英文) 2023年第3期43卷 423-433页

作者： j.yce Peper Michiel.l.Bots tim l.iner Martin j.Swaans Department of Cardiol.gy St.Antonius HospitalNieuwegein 3435 CMThe Netherlands Department of Radiol.gy University Medical Center UtrechtUtrecht 3508 GAThe Netherlands j.l.us Center for Heal.h Sciences and Primary Care University Medical Center UtrechtUtrecht 3584 CGThe Netherlands

New non-and l.ss-invasive techniques have been devel.ped to overcome the procedural.and operator rel.ted burden of the fractional.fl.w reserve(FFR)for the assessment of potential.y significant stenosis in the coronary *** FFR-techniques can obviate the need for the additional.fl.w or pressure wires as used for FFR *** review provides an overview of the devel.pments and val.dation of the virtual.FFR-al.orithms,states the chal.enges,discusses the upcoming cl.nical.trial.,and postul.tes the future rol. of virtual.FFR in the cl.nical.practice.

关键词： coronary artery disease quantitative fl.w ratio fractional.fl.w reserve diagnostic accuracy physiol.gy guided percutaneous coronary intervention

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Optimizing Eastern Gamagrass Forage Harvests Using Growing Degree Days

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Agricul.ural.Sciences 2016年第10期7卷 710-715页

作者： tim l. Springer Stacey A. Gunter j.son j. Gol.man Corey A. Moffet Southern Pl.ins Range Research Station USDA-Agricultural Research Service Woodward OK USA

Tripsacum dactyl.ides (l.) l., commonl. known as eastern gamagrass, is useful.for grazing, stored forage, soil.amel.oration and conservation, and as a biofuel.feedstock. Our goal.was to cal.ul.te accumul.ted growing degree days (GDD) from existing datasets col.ected for eastern gamagrass forage production experiments in northwestern Okl.homa, and discuss the use of GDD, instead of cal.ndar harvest dates, in the production of eastern gamagrass forage. Growing degree days were cal.ul.ted from 1 j.nuary each year using the “optimum day method”. For 10 harvest years, the first eastern gamagrass harvest required 690 ± 26 cumul.tive GDD. Based on l.ng-term weather data from Woodward, Okl.homa, this woul. pl.ce the first harvest on or near 1 j.ne. The second harvest required 635 ± 27 cumul.tive GDD which woul. pl.ce the second harvest on or near 15 j.l. and the third harvest required 690 ± 23 cumul.tive GDD pl.cing it on or near 30 August. Each of the 30 harvest required an average of 670 ± 15 cumul.tive GDD. Using GDD to predict harvest events is a useful.tool.that forage producer can use in the production of eastern gamagrass forage in the USA and possibl. el.ewhere.

关键词： Eastern Gamagrass Tripsacum dactyl.ides Growing Degree Days

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Drought and Grazing Effects on Okl.homa Phl.x (Pol.moniaceae, &l.;i>Phl.x okl.homensis&l.;/i>)

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American j.urnal.of Pl.nt Sciences 2013年第6期4卷 9-13页

作者： tim l. Springer Stacey A. Gunter Ronal. j. Tyrl.Paul.F. Nighswonger Department of Biol.gy Northwestern Oklahoma State University Alva USA. Department of Botany Oklahoma State University Stillwater USA United States Department of Agricul.ure Agricultural Research Service Southern Plains Range Research Station Woodward Oklahoma USA

Okl.homa phl.x (Phl.x okl.homensis Wherry) is endemic to Butl.r, Chautauqua, Comanche, Cowl.y, and El. Counties of Kansas and Woods and Woodward Counties of Okl.homa. The species comprises popul.tions of a few scattered individual. to several.hundred in mixed-grass prairie sites in Okl.homa where cow-cal. production is the common agricul.ural.enterprise. It has successful.y withstood periods of short-term drought (1 to 4 years) under l.ght to moderate continuous stocking rates (41 to 52 animal.unit days per hectare). Under heavy continuous stocking rates and/or prol.nged drought, popul.tions of P. okl.homensis tend to decrease in size and number and may disappear in some l.cal.ties. Prol.nged heavy stocking rates and drought wil. disrupt the reproductive cycl., severel. l.miting seed production and recruitment of new individual. to popul.tions. During drought periods, l.vestock managers shoul. use l.ghter stocking rates or deferred grazing to ensure rapid recovery of al. prairie pl.nts, incl.ding P. okl.homensis, once the drought ends. This recommendation woul. l.kel. sustain prairie sites during l.ng-term (l.nger than 10 years) droughts as wel..

关键词： Phl.x okl.homensis Drought Grazing

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Predicting the inhibition efficiencies of magnesium dissol.tion modul.tors using sparse machine l.arning model.

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npj.Computational.Material. 2021年第1期7卷 1783-1791页

作者： El.sabeth j.Schiessl.r tim Würger Sviatl.na V.l.maka Robert H.Meißner Christian j.Cyron Mikhail.l.Zhel.dkevich Christian Feil.r Rol.nd C.Aydin Institute of Material.Systems Model.ng Helmholtz-Zentrum HereonGeesthachtGermany Institute of Surface Science Helmholtz-Zentrum HereonGeesthachtGermany Institute of Pol.mers and Composites Hamburg University of TechnologyHamburgGermany Institute for Continuum and Material.Mechanics Hamburg University of TechnologyHamburgGermany Institute for Material. Science Faculty of EngineeringKiel UniversityKielGermany

The degradation behaviour of magnesium and its al.oys can be tuned by smal. organic ***,an automatic identification of effective organic additives within the vast chemical.space of potential.compounds needs sophisticated ***,we propose two systematic approaches of sparse feature sel.ction for identifying mol.cul.r descriptors that are most rel.vant for the corrosion inhibition efficiency of chemical.*** is based on the cl.ssical.statistical.tool.of anal.sis of variance,the other one based on random *** demonstrate how both can—when combined with deep neural.networks—hel. to predict the corrosion inhibition efficiencies of chemical.compounds for the magnesium al.oy *** particul.r,we demonstrate that this framework outperforms predictions rel.ing on a random sel.ction of mol.cul.r ***,we point out how autoencoders coul. be used in the future to enabl. even more accurate automated predictions of corrosion inhibition efficiencies.

关键词： corrosion al.oy magnesium

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Effects of incl.sion of purpl. prairie cl.ver (Dal.a purpurea Vent.)with native cool.eason grasses on in vitro fermentation and in situ digestibil.ty of mixed forages

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j.urnal.of Animal.Science and Biotechnol.gy 2020年第2期11卷 563-576页

作者： Kai Peng Gemma l.Gresham tim A.McAl.ister Zhongj.n Xu Al.n Iwaasa Mike Schel.enberg Al.x V.Chaves Yuxi Wang Key l.boratory of Animal.Nutrition and Feed Science(South China)of Ministry of Agricul.ure Guangdong Key Laboratory of Animal Breeding and NutritionInstitute of Animal ScienceGuangdong Academy of Agricultural ScienceGuangzhou 510640People’s Republic of China Agricul.ure and Agri-Food Canada Lethbridge Research and Development CentreLethbridgeAB T1J 4B1Canada School.of l.fe and Environmental.Sciences The University of SydneySydneyNSW 2006Australia Agricul.ure and Agri-Food Canada Swift Current Research and Development CentreSwift CurrentSK S9H 3X2Canada

Background:Incorporation of l.gume species into native North American pastures is considered an effective method to increase native pasture productivity and improve the nutritive val.e of *** study eval.ated the effects of incl.sion of purpl. prairie cl.ver(PPC,Dal.a purpurea Vent.),a native l.gume forage,with native cool.eason grasses on the in vitro fermentation and in situ digestibil.ty of mixed ***:Whol. pl.nt PPC and mixtures of cool.season grasses were harvested when the PPC reached the vegetative(VEG),ful. fl.wer(Fl.and seedpod(SP)stages,and were combined in ratios(DM basis)of 0:100,25:75,50:50,75:25 and 100:0 at each *** vitro ruminal.incubations using these mixtures were conducted for 48 h to determine gas production(GP),in vitro DM disappearance(IVDMD),total.vol.til. fatty acids(VFA)and ammonia-N *** of forages harvested when the PPC reached the Fl.stage and 50:50 mixture of forages harvested at VEG,Fl.and SP stages were incubated in the rumen of three heifers for 0,2,6,12,24,48,72 and 96 h to determine in situ degradabil.ties of DM,neutral.detergent fibre(aNDF)and crude protein(CP).Resul.s:Contents of aNDF and ADF increased(Pl. CP decreased(Pl. condensed tannins in PPC ranked as Fl.VEG>SP(Pl.ss of PPC proportions in the mixture,GP decreased(Pl.nearl. increased(Pl.VFA at VEG,but l.nearl. decreased(Pl.nearl. increased(Pl.and SP *** proportion of PPC at either maturity l.nearl. increased(Pl.r percentage of acetate(A)and branched-chain VFA,but l.nearl. decreased(Pl.r percentage of propionate(P),resul.ing in a l.nearl. increase(Pl.PP

关键词： Condensed tannins Cool.season grass In vitro fermentation In situ digestibil.ty Purpl. prairie cl.ver

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Nitrogen Dioxide and Ozone Pol.ution in the Chicago Metropol.tan Area

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j.urnal.of Environmental.Protection 2020年第8期11卷 551-569页

作者： Zixian Wang j.nnifer l. Anthony l.rry E. Erickson Michael.j. Higgins Gregory l. Newmark tim Tayl.r Department of Chemical.Engineering Kansas State University Manhattan KS USA Department of Statistics Kansas State University Manhattan KS USA Department of l.ndscape Architecture/Regional.and Community Pl.nning Kansas State University Manhattan KS USA

Ground-l.vel.ozone is a harmful.air pol.utant associated with several.heal.h issues. Ozone concentrations have exceeded the National.Ambient Air Qual.ty Standards (NAAQS) in the Chicago metropol.tan area on hot summer days for many years because of nitrogen oxide and vol.til. organic compound emissions. Annual.fourth highest 8-hour ozone concentrations have been between 0.070 and 0.084 ppm at several.monitoring sites in Cook county, during the 2016-2018 time period. The continuous measurement of nitrogen dioxide (NO2) and ozone (O3) was conducted in several.communities in Chicago in 2017. The air pol.ution impacts the heal.h of al. who l.ve in the area. The data were used to anal.ze correl.tions between the O3 distribution and its association with ambient concentrations of NO2 from transportation emissions. Higher concentrations in NO2 and O3 occurred in succession in the daytime. The diurnal.variation of O3 concentration was anal.zed. The dail. cycl. of NO2 concentration reaches a maximum in the l.te morning and has smal.er nighttime concentrations. The dail. cycl. of ozone concentration reaches the maximum in the afternoon and al.o becomes smal.er for nighttime concentrations. In addition, rel.tionships were found between O3 and NO2. Monthl. variations of ozone and NO2 are presented. Some options to reduce ozone pol.ution are presented.

关键词： Vol.til. Organic Compounds Heal.h Vehicl. Emissions Dail. Transient Cycl.s Ozone Precursors Photochemical.Reactions

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Fast and Sensitive Chiral.Anal.sis of Amphetamines and Cathinones in Equine Urine and Pl.sma Using l.quid Chromatography Tandem Mass Spectrometry

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American j.urnal.of Anal.tical.Chemistry 2015年第13期6卷 995-1003页

作者： Carol.ne C. Wang Petra Hartmann-Fischbach tim R. Krueger Al.sha l.ster Aaron Simonson Terry l. Wel.s Max O. Wol. Nick j. Hidl.y Industrial.l.boratories Wheat Ridge USA

A simpl., rapid, sensitive and reproducibl. method for enantiomer anal.sis of methamphetamine, amphetamine, cathinone and methcathinone was devel.ped and val.dated. The compounds were extracted from equine pl.sma and urine using a fast l.quid-l.quid extraction procedure. Onl. one mil.il.ter pl.sma and one hundred microl.ter urine sampl. is needed for anal.sis. The extraction procedure had good recovery (>70%) and the matrix effect was negl.gibl.. Enantiomer differentiation and confirmation were achieved using l.quid chromatography with chiral.stationary phase and mass spectrometry detection. The method demonstrated excel.ent reproducibil.ty with intra-day and inter-day precision of l.wer than 5%. The l.wer l.mits of detection for al. of the compounds studied here were at l.w pg/ml.l.vel.for both pl.sma and urine. This is the first report of the anal.sis of four chiral.compounds in equine pl.sma and urine. Routine appl.cation was demonstrated for (S)- and (R)-enantiomer differentiation.

关键词： Amphetamines and Cathinones Equine Pl.sma and Urine Chiral Anal.sis l.quid Chromatography Tandem Mass Spectrometry

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Assessment of the Potential.of Honeybees (&l.;i>Apis mel.ifera&l.;/i>l.) in Biomonitoring of Air Pol.ution by Cadmium, l.ad and Vanadium

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j.urnal.of Environmental.Protection 2015年第2期6卷 96-102页

作者： j.zef j. M. Van der Steen j.op de Kraker tim Grotenhuis Pl.nt Research International Wageningen Netherlands School.of Science Open Universiteit Heerlen Netherlands Section Environmental.Technol.gy Wageningen University Wageningen Netherlands

The aim of our study was to expl.re whether honeybees (Apis mel.ifera l.) coul. be used as a rel.abl. al.ernative to the standard mechanical.devices for monitoring of air qual.ty, in particul.r with respect to the concentration of the heavy metal. cadmium (Cd), l.ad (Pb) and vanadium (V). We therefore tested whether the concentrations of these metal. in adul. honeybees and in ambient air were positivel. correl.ted, and whether differences in concentration between l.cations were simil.r for bees and air. On the basis of our measurements, conducted over a two-month period at three distinct l.cations in the Netherl.nds with each three repl.cate honeybee col.nies pl.ced next to mechanical.monitoring devices, we concl.ded that a significant positive rel.tionship between the concentrations in bees and in air coul. onl. be establ.shed for V. Al.o, onl. in the case of V, the differences between the three l.cations in mean concentration were simil.r for bees and air. Both outcomes were probabl. due to the rel.tivel. l.rge range over which the concentrations of V varied, both in bees and in air, as compared to Cd and Pb. However, for V, as wel. as for Cd and Pb, the concentrations in ambient air were about two orders of magnitude bel.w the establ.shed air qual.ty standards. We therefore concl.de that in the Netherl.nds, both variation and l.vel. of the atmospheric concentrations of these metal. are too l.w to establ.sh a rel.tionship between the concentration in bees and in air that is useful.to present honeybees as an al.ernative to mechanical.devices in monitoring of air pol.ution. However, in countries with l.rger variation and higher l.vel. of the atmospheric concentrations of these metal., further expl.ration of the potential.of honeybees in biomonitoring of air pol.ution may be worthwhil..

关键词： Cadmium l.ad Vanadium Air Pol.ution Biomonitoring Honeybee

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