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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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Anal.sis of roof and pil.ar fail.re associated with weak fl.or at a l.mestone mine

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International.j.urnal.of Mining Science and Technol.gy 2016年第3期26卷 471-476页

作者： Murphy Michael.M. El.enberger j.hn l. Esterhuizen Gabriel.S. Mil.er tim Office of Mine Safety and Heal.h Research National Institute of Occupational Safety and Health East Fairfiel. Company

A l.mestone mine in Ohio has had instabil.ty probl.ms that have l.d to massive roof fal.s extending to the surface. This study focuses on the rol. that weak, moisture-sensitive fl.or has in the instabil.ty *** NIOSH research rel.ted to this subj.ct did not incl.de anal.sis for weak fl.or or weak bands and recommended that when such issues arise they shoul. be investigated further using a more advanced anal.sis. Therefore, to further investigate the observed instabil.ty occurring on a l.rge scal. at the Ohio mine, Fl.C3 D numerical.model. were empl.yed to demonstrate the effect that a weak fl.or has on roof and pil.ar stabil.ty. This case study wil. provide important information to l.mestone mine operators regarding the impact of weak fl.or causing the potential.for roof col.apse, pil.ar fail.re, and subsequent subsidence of the ground surface.

关键词： Underground l.mestone Ground control.Case study Weak fl.or Instabil.ty

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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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Current Medical.Science 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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Potassium isotopes trace the formation of j.venil. continental.crust

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Geoscience Frontiers 2024年第6期15卷 37-42页

作者： Hamed Gamal.l.ien Kun Wang tim E.j.hnson j.an-Feng Ma Mohamed Abu Anbar Xinmu j.Zhang Hugo K.H.Ol.erook Christopher l.Kirkl.nd Department of Earth Sciences College of Engineering and Physical SciencesKhalifa UniversityAbu DhabiUnited Arab Emirates School.of Earth and Pl.netary Sciences Curtin UniversityGPO Box U1987PerthWA 6845Australia Department of Earth Environmentaland Planetary Sciences and McDonnell Center for the Space SciencesWashington University in St.LouisMO 63130USA timescal.s of Mineral.Systems Group School of Earth and Planetary Sciences&John de Laeter CentreCurtin UniversityAustralia Key l.boratory of Mineral.gy and Metal.ogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhouChina Geol.gy Department Faculty of ScienceTanta University31527 TantaEgypt

Constraining the processes associated with the formation of new(j.venil.)continental.crust from mantl.-derived(basal.ic)sources is key to understanding the origin and evol.tion of Earth’s *** we present high-precision measurements of stabl. isotopes of potassium(K)from Earth’s most vol.minous pl.giogranites,exposed near El.Shadl. in the Eastern Desert of *** pl.giogranites exhibit a wide range of d41K val.es(–0.31‰±0.06‰to 0.36‰±0.05‰;2 SE,standard error)that are significantl. higher(isotopical.y heavier)than mantl. val.es(–0.42‰±0.08‰).Isotopic(87Sr/86Sr and^(143)Nd/^(144)Nd)and trace el.ment data indicate that the l.rge variation in d41K was inherited from the basal.ic source rocks of the El.Shadl. pl.giogranites,consistent with an origin through partial.mel.ing of hydrothermal.y-al.ered mid-to-l.wer oceanic *** data demonstrate that K isotopes have the potential.to better constrain the source of granitoid rocks and thus the secul.r evol.tion of the continental.crust.

关键词： Potassium isotopes Pl.giogranites Arabian-Nubian Shiel. Neoproterozoic Crustal.growth

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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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Upgrading Pathways of Intel.igent Manufacturing in China:Transitioning across Technol.gical.Paradigms

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Engineering 2019年第4期5卷 691-701页

作者： Yuan Zhou j.yuan Zang Zhongzhen Miao tim Minshal. School.of Publ.c Pol.cy and Management Tsinghua UniversityBeijing 100084China Center for Strategic Studies Chinese Academy of EngineeringBeijing 100088China Institute for Manufacturing University of CambridgeCambridge CB3 0FSUK

Intel.igent technol.gies are l.ading to the next wave of industrial.revol.tion in *** devel.ped economies,firms are embracing these advanced technol.gies fol.owing a sequential.upgrading strategy-from digital.manufacturing to smart manufacturing(digital.networked),and then to newgeneration intel.igent manufacturing ***,Chinese firms face a different *** the one hand,they have diverse technol.gical.bases that vary from l.w-end el.ctrified machinery to l.ading-edge digital.network technol.gies;thus,they may not fol.ow an identical.upgrading *** the other hand,Chinese firms aim to rapidl. catch up and transition from technol.gy fol.owers to probabl. frontrunners;thus,the turbul.nces in the transitioning phase may trigger a precious opportunity for l.apfrogging,if Chinese manufacturers can swiftl. acquire domain expertise through the adoption of intel.igent manufacturing *** study addresses the fol.owing question by conducting mul.ipl. case studies:Can Chinese firms upgrade intel.igent manufacturing through different pathways than the sequential.one fol.owed in devel.ped economies?The data sources incl.de semistructured interviews and archival.*** study finds that Chinese manufacturing firms have a variety of pathways to transition across the three technol.gical.paradigms of intel.igent manufacturing in nonconsecutive *** finding impl.es that Chinese firms may strategize their own upgrading pathways toward intel.igent manufacturing according to their capabil.ties and industrial.specifics;furthermore,this finding can be extended to other catching-up *** paper provides a strategic roadmap as an expl.natory guide to manufacturing firms,pol.cymakers,and investors.

关键词： Intel.igent manufacturing Upgrading pathways China’s manufacturing Digital.zation Networkization New-generation intel.igent manufacturing

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