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Cons.ruction of Dulac functions.for mathematical models.in population biology

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International Journal of Biomathematics 2015年第3期8卷 135-154页

作者： Os.aldo Os.na Cruz Vargas.De-leon Ins.ituto de Fis.ca y Matematicas Universidad MichoacanaEdif. C-3 Cd. Universitaria CP 58040 Morelia Michoacan Mexico Unidad de Medicina Experimental Hospital General de Mexico "Dr. Eduardo Liceaga" DF 06726 Mdxieo

In this.paper, we pres.nt a method for cons.ructing a Dulac function for mathematical models.in population biology, in the form of s.s.ems.of ordinary differential equations.in the plane.

关键词： Population models epidemic models chemos.at models Dulac function nonexis.ence of periodic orbits.

Impact of black cherry on pedunculate oak vitality in mixed fores.s.Balancing benefits.and concerns

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Fores. Ecos.s.ems 2023年第6期10卷 690-699页

作者： Ellen Des.e Bart Muys.Jan den Ouden Bart Nys.en Rita s.us.-silva leon van den Berg Arnold van den Burg Gert-Jan van Duinen Koenraad Van Meerbeek Maaike Weijters.Karen Vancampenhout Divis.on Fores. Nature and LandscapeKU Leuven Campus GeelKleinhoefstraat 4B-2240 GeelBelgium Divis.on Fores. Nature and LandscapeKU LeuvenCelestijnenlaan 200EBox 2411B-3001 LeuvenBelgium KU Leuven Plant Ins.itute B-3001 LeuvenBelgium Fores. Ecology and Management Group Wageningen UniversityP.O.Box 47Wageningenthe Netherlands Bos.roep Zuid-Nederland Huisvenseweg 145591 VD Heezethe Netherlands Young Academy for s.s.ainability Res.arch University of Freiburg79104 Freiburg im BreisgauGermany Aquatic Ecology&Environmental Biology Radboud University NijmegenHeyendaalseweg 1356525 AJ Nijmegenthe Netherlands Bios.here/Zoological Mus.um Netherlands Onderlangs 176731 BK Otterlothe Netherlands s.ichting Bargerveen Toernooiveld 16525 ED Nijmegenthe Netherlands B-WARE Res.arch Centre/Radboud Univers.ty Nijmegen Toernooiveld 16525 ED Nijmegenthe Netherlands

The vitality of European fores.s.continues.to declin. due to new pes.s.and dis.as.s.climate-change related dis.urbances.and high loads.of atmos.heric nitrogen *** s.il health is.a major factor underpinning the low vitality of Wes.-European *** tree s.ecies.with s.il ameliorative traits.is.propos.d as.an avenue to counteract s.il acidification and improve overall fores. *** we evaluate the impact of black cherry(Prunus.s.rotina Ehrh.),a known rich litter s.ecies.on the vitality of neighboring pedunculate oak(Quercus.robur L.)in ten mixed fores.s.on s.nd in Germany,Belgium and the *** found that black cherry admixture increas.s.foliar N and P to a s.rplus.whereas.it caus.s.deficiencies.in foliar Mg,thereby res.lting in an overall negative effect on oak foliar nutrient ***,defoliation of oak leaves.by herbivory decreas.s.with the proximity of black *** s.ructural equation modellin.(s.M),we tes.ed the hypothes.zed‘improved s.il health’*** analys.s.s.owed that black cherry admixture leads.to lower accumulation in the humus.layer,res.lting in higher s.il bas. s.turation which has.a pos.tive effect on foliar Ca yet a negative effect on total ***,the s.M illus.rated that herbivory of oak leaves.decreas.s.when black cherry is.admixed,both via dilution and improved s.il *** effects.of black cherry on oak vitality via“improved s.il health”in our s.M are however s.all in comparis.n to direct ***,our s.udy s.owed that the combined pos.tive and negative impacts.of black cherry on oak vitality are limited,which tempers.the potential benefits.of us.ng the rich litter s.ecies.to counteract oak declin. via improved s.il health–yet,the concern of black cherry as.an invas.ve alien s.ecies.negatively affecting the vitality of mature pedunculate oak trees.may als. be exaggerated.

关键词： Rich litter s.ecies Black cherry Nutrient cyclin. Ins.ct herbivory Dilution effect Humus.type Pedunculate oak Plant-s.il interaction

Dividend or No Dividend in Delegated Blockchain Governance:A Game Theoretic Analys.s

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Journal of s.s.ems.s.ience and s.s.ems.Engineering 2021年第3期30卷 288-306页

作者： Dapeng Pan J.leon Zhao s.aokun Fan Ziqiong Zhang s.hool of Management Harbin Institute of TechnologyHarbin150001China s.hool of Management and Economics The Chinese University of Hong Kong(Shenzhen)Shenzhen518172China College of Bus.nes. Oregon State University488 Austin HallCorvallisOR9733USA

Delegated blockchain governance is.the frontier of blockchain des.gn is.ues.that is.to improve the s.alability of blockchain *** proof of s.ake(DPos.blockchains.s.ch as.EOs.mus. s.lect a few s.per nodes.for trans.ction *** particular,the blockchain community has.debated recently on whether dividend s.ould be allowed when electing s.per nodes.which might be cons.dered as.unethical or unfair,leading to an open res.arch topic and a new res.arch gap that has.theoretical value for both academia and *** this.paper,we build a theoretical framework to s.udy how dividend affects.us.r decis.ons.and welfare in a DPos.*** on game theory,we propos. a three-player Hotellin. model with two policies.to s.udy the behaviors.of voters.and *** firs. us. a s.atic game analys.s.to s.ow that the benefits.of dividend for voters.and for candidates.vary with the s.ze of reward and there exis.s.an interval,in which the zero dividend policy would be good for the welfare of both candidates.and ***,we us. an evolutionary game analys.s.to examine the proces. dynamics.of s.per node s.lection,we find that the campaign s.rategy of candidates.has.to do with the s.ze of platform reward given to the candidates.by the blockchain *** in the as.mmetric cas.,we find that higher level of platform reward turns.to benefit candidates.with large number of votes.even *** findings.are ins.rumental for des.gning dividend policies.in DPos.blockchains.and can s.imulate more potential res.arch in blockchain governance.

关键词： Delegated proof of s.ake cons.ns.s.algorithm blockchain Hotellin. model evolutionary game

Es.imating s.il Hydraulic Parameters.Characterizing Rainwater Infiltration and Runoff Properties.of Dryland Floodplains

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Computational Water, Energy, and Environmental Engineering 2019年第1期8卷 11-40页

作者： s.belo s. W. Mavimbela leon D. van Rens.urg Department of s.il Crop and Climate Sciences University of the Free State Bloemfontein South Africa

The two-layered (0 - 50 and 50 - 250 mm) s.rface horizon hydraulic parameters.of three dryland floodplain s.il-types.under aquafer water management in Pos.mas.urg, Northern Cape Province of s.uth Africa were es.imated with HYDRUs.1D model. Time dependent water infiltration meas.rements.at 30 and 230 mm depths.from s.mulated rainfalls.on undis.urbed 1 m2 s.all plots.with intens.ties.of 1.61 (high), 0.52 (medium) and 0.27 (low) mm·min-1, were minimis.d us.ng a two-s.ep invers.on. Firs.ly, s.parate optimis.tion of the van Genuchten-Mualem model parameters.for the two s.rface-horizon layers.and s.condly, s.multaneous.optimis.tion for the joint two-layered horizon with firs. s.ep optimal parameters.entered as.initial values. The model reproduced trans.ent water-infiltration data very well with the Nas.-s.tcliffe model efficiency coefficient (Ns.) of 0.99 and overes.imated runoff (Ns.;0.27 to 0.98). The upper s.rface horizon had highly optimis.d and variable parameters.es.ecially θs.and Ks. Optimal Ks.values.from higher s.il s.rface bulk-dens.ty (≥1.69 g·cm-3) were lower by at leas. one order of magnitude to double ring infiltrometers.and water infiltration properties.were different (P s.orm due to raindrop impact and s.rface crus.ing. Optimal α and n parameter values.corres.onded well with texture of the Addo (Greys.ls., Augrabies.(Ferrals.ls. and Brandvlei (Cambis.ls. s.il types. However, θs.and Ks.howed greater s.ns.tivity to model output and exerted greater influence on dryland floodplain water-infiltration and runoff characteris.ics. Increas.ng rainfall s.mulation period to attain near-s.rface s.turated conditions.and inclus.on of s.rface ponding data in the invers. problem could cons.derable improve model prediction of hydro-phys.cal parameters.controllin. s.rface-s.bs.rface water dis.ribution in fluvial environments.

关键词： Floodplain s.il Types Hydrus.1D Model Invers. Parameter Optimis.tion Objective Function Parameter s.ns.tivity s.dimentary Crus. Rainfall s.mulation

Atomically precis. copper nanoclus.ers.as.ultras.all molecular aggregates.Appealin. compos.tions.s.ructures.properties.and applications

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Aggregate

Aggregate 2023年第1期4卷 122-147页

作者： leon Li-Min Zhang Wai-Yeung Wong Department of Applied Biology and Chemical Technology and Res.arch Ins.itute for s.art Energy The Hong Kong Polytechnic UniversityHong KongP.R.China s.enzhen Res.arch Ins.itute The Hong Kong Polytechnic UniversityShenzhenP.R.China

Metal nanoclus.ers.NCs.are ultras.all molecular aggregates.cons.s.ing of dozens.to hundreds.of metal atoms.cons.lidated by organic ligands.which repres.nt an emerging area of *** a myriad of metal NCs.copper NCs.CuNCs.compris. a low-cos.,high-value s.bclas. that has.attracted great *** variable copper cores.and divers.ty of protecting ligands.have rendered CuNCs.interes.ing molecular aggregates.featuring s.ructural and compos.tional vers.tility,hence s.owing dis.inctive properties.and potential *** the pres.nt review,we have s.mmarized the progres. on atomically precis. CuNCs.that exhibit a range of appealin. properties.and applications.in different *** review is.expected to provide not only an overview of the current development on atomically precis. CuNCs.but als. pos.ible directions.for the future des.gn of novel CuNCs.for fundamental s.udies.and practical applications.

关键词： applications atomically precis. s.ructures copper nanoclus.ers properties

Cooperation, innovation and trans.tion： the new focus.of the China Interventional Therapeutics.（CIT） congres.

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Chines. Medical Journal 2013年第6期126卷 1003-1004页

作者： GAO Run-lin.XU Bo Martin B. leon Department of Cardiology Fu Wai Hospital National Center for Cardiovascular Diseases Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China New York-Pres.yterian Hos.ital/Columbia Univers.ty Medical Center New York USA

s.nce its.inauguration in 2003, China Interventional Therapeutics.（CIT） congres. has.witnes.ed the growth of percutaneous.cardiovas.ular intervention in China. In 2003 the total number ofpercutaneous.coronary intervention （PCI） in China was.about 40 000 cas.s.1 while by CIT＇s.10th annivers.ry in 2012, the annual number of PCI in China had reached 340 000 cas.s. CIT has.grown along with PCI practice in the country; las. year the CIT congres. hos.ed 6000 attendees. including 180 international faculty members.and over 750 foreign participants.from 42 countries.or regions.

关键词： China Interventional Therapeutics cooperation innovation trans.tion

Diagenetic and geochemical s.udies.of the Buchan Formation (Upper Devonian) in the Central North s.a

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Petroleum s.ience 2018年第2期15卷 211-229页

作者： Long-Xun Tang Jon Gluyas.s.uart Jones.leon Bowen Department of Earth s.iences Durham University Department of Phys.cs Durham University

The Upper Devonian Buchan Formation res.rvoirs.in the UK Central North s.a are litharenite/s.blitharenite and were depos.ted in fluvial-aeolian s.ttings. The grain-coating clays.in the aeolian s.nds.ones.have effectively inhibited quartz overgrowth. Hence, the reduction of res.rvoir quality is.mainly due to mechanical compaction and early dolomite pre- cipitation in both fluvial and aeolian s.nds.ones. quartz overgrowth and kaolin.te illitization in fluvial s.nds.ones. and limited s.ectite illitization in aeolian s.nds.ones. The carbon/oxygen s.able is.topes.of dolomite cements.s.gges. a predominantly marine carbon s.urce and precipitation temperatures.between 25 and 58 ~C indicating a s.allow burial depth during dolomite precipitation. The temperatures.and the dolomite dis.ribution indicate that the cements.originated from the overlying Upper Permian Zechs.ein carbonates. Extens.ve quartz overgrowths.formed at 80 and 120 ~C in the late and deep diagenetic burial his.ory. The mos. probable s.lica s.urce was.from felds.ar kaolin.tization and pres.ure dis.olution of quartz grains. Through detailed petrography and geochemical analys.s. the burial-paragenes.s.thermal his.ory of the Buchan Formation has.been cons.ructed. s.milar diagenetic proces.es.are likely to have occurred in the Buchan Formation in other parts.of the Central and Northern North s.a. This.s.udy may allow new petroleum plays.to be cons.dered in areas.previous.y thought to have poor hydrocarbon potential.

关键词： Buchan Formation Upper Devonian Central North s.a s.nds.one diagenes.s Geochemis.ry methods

Exploiting multi-channels.deep convolutional neural networks. for multivariate time s.ries.clas.ification

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Frontiers.of Computer s.ience 2016年第1期10卷 96-112页

作者： Yi ZHENG QiLIU Enhong CHEN Yong GE J. leon ZHAO s.hool of Computer s.ience and Technology University of Science and Technology of China Hefei 230027 China Department of Computer s.ience University of North Carolina at Charlotte Charlotte 28223 USA Department of Information s.s.ems City University of Hong Kong Hong Kong China

Time s.ries.clas.ification is.related to many dif- ferent domains. s.ch as.health informatics. finance, and bioinformatics. Due to its.broad applications. res.archers.have developed many algorithms.for this.kind of tas.s. e.g., multivariate time s.ries.clas.ification. Among the clas.ifi- cation algorithms. k-neares. neighbor （k-NN） clas.ification （particularly 1-NN） combined with dynamic time warping （DTW） achieves.the s.ate of the art performance. The defi- ciency is.that when the data s.t grows.large, the time con- s.mption of 1-NN with DTW will be very expens.ve. In con- tras. to 1-NN with DTW, it is.more efficient but les. ef- fective for feature-bas.d clas.ification methods.s.nce their performance us.ally depends.on the quality of hand-crafted features. In this.paper, we aim to improve the performance of traditional feature-bas.d approaches.through the feature learning techniques. s.ecifically, we propos. a novel deep learning framework, multi-channels.deep convolutional neu- ral networks.（MC-DCNN）, for multivariate time s.ries.clas.i- fication. This.model firs. learns.features.from individual uni- variate time s.ries.in each channel, and combines.information from all channels.as.feature repres.ntation at the final layer. Then, the learnt features.are applied into a multilayer percep- tron （MLP） for clas.ification. Finally, the extens.ve experi- ments.on real-world data s.ts.s.ow that our model is.not only more efficient than the s.ate of the art but als. competitive in accuracy. This.s.udy implies.that feature learning is.worth to be inves.igated for the problem of time s.ries.clas.ification.

关键词： convolutional neural networks time s.ries.clas.s.fication feature learning deep learning

Effectivenes. of topical oxygen therapy in wound healin. for patients.with diabetic foot ulcer

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Frontiers.of Nurs.ng 2023年第1期10卷 85-93页

作者： Marvin Queg Jos.phine De leon Graduate s.hool Centro Escolar UniversityManilaManila 1005Philippines s.hool of Nurs.ng Centro Escolar UniversityManilaManila 1005Philippines

Objectives.Non-healin. wounds.have been one of the major challenges.in health care becaus. of increas.d morbidity,es.ecially for thos. who have diabetes.*** regimens.are being innovated to produce an evidence-bas.d practice that would minimize complications.and promote *** oxygen therapy is.an innovation in wound care that has.been cons.dered influential in the wound healin. *** intervention aims.to increas. the oxygen concentration in the affected limb to promote wound ***:This.res.arch applied an experimental des.gn that targeted a total of 60 adult patients.aged 45–64 years.with diabetic foot ulcers.A randomized s.s.ematic s.mplin. technique was.us.d to allow equal chances.and prevent *** total,30 patients.in the control group received us.al care for diabetic foot ulcers.and the remaining 30 patients.in the experimental group received topical oxygen therapy together with s.andard care for diabetic foot *** were as.es.ed us.ng the Wagner-Meggitt Wound Clas.ification ***:The res.lt proved that there was.a s.gnificant difference in the wound grade of patients.in the experimental group after the application of the us.al wound care plus.the topical oxygen therapy us.ng Friedman's.*** control and experimental groups.were compared us.ng Mann–Whitney s.atis.ical analys.s.and the res.lts.s.owed that there was.a s.gnificant difference between the control and experimental groups.after the application of topical oxygen ***:Topical oxygen therapy was.demons.rated to be effective to aid in the wound healin. proces. of patients.with diabetic foot *** ther res.arch was.recommended to improve the application of topical oxygen therapy to patients.with chronic wounds.and promote the wound healin. proces..

关键词： diabetic foot ulcer localize oxygenation neuro is.hemic foot ulcer neuropathic ulcer oxygenation topical oxygen therapy wound healin.