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m.an and fluctuating velocity fields of a diam.nd turbulent jet

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Chinese Physics B 2013年第3期22卷 344-351页

作者：徐敏义张健鹏米建春 nathan G.j. Kalt P.A.m. State Key Laboratory of Turbulence & Com.lex System. College of EngineeringPeking University m.rine Engineering College Dalian Maritime University Centre for Energy Technology and School of m.chanical Engineering University of AdelaideSA 5005Australia

The present paper reports the first investigation on a turbulent jet issuing from.a diam.nd orifice（hereafter term.d a ＂diam.nd jet＂） with an aspect ratio of *** m.asurem.nts were conducted in the transitional region,and the exit Reynolds num.er of the jet was *** com.arison,a round jet with identical norm.lized boundary conditions was also *** is shown that the diam.nd jet decays and spreads faster than the round jet does over the m.asured flow *** axis-switching phenom.non is observed in the diam.nd *** both jets display prim.ry coherent structures in the near field,these structures are found to break down m.re rapidly in the diam.nd jet,due to the higher three-dim.nsionality of the ***,the stream.ise com.onents of the Reynolds norm.l stress and all the shear stresses reach their m.xim. around the location of the m.xim.l m.an shear while the m.xim. of the lateral com.onents of the Reynolds norm.l stresses occur around the centreline of the jet.

关键词： turbulent jet non-circular jet PIV m.asurem.nt jet entrainm.nt

Zwitterion-doped liquid crystal speckle reducers for im.ersive displays and vectorial im.ging

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Light(Science & Applications) 2023年第11期12卷 2363-2377页

作者： Yihan jin nathan P.Spiller Chao He Graham. Faulkner m.rtin j.Booth Steve j.Elston Stephen m.m.rris Departm.nt of Engineering Science University of OxfordParks RoadOxford OX13PJUK

Lasers possess m.ny attractive features(e.g.,high brightness,narrow linewidth,well-defined polarization)that m.ke them.the ideal illum.nation source for m.ny different scientific and technological endeavors relating to im.ging and the display of high-resolution ***,their high-level of coherence can result in the form.tion of noise,referred to as speckle,that can corrupt and degrade ***,we dem.nstrate a new electro-optic technology for com.atting laser speckle using a chiral nem.tic liquid crystal(LC)dispersed with zwitterionic *** are presented that dem.nstrate when driven at the optim.m.electric field conditions,the speckle noise can be reduced by>90%resulting in speckle contrast(C)values of C=0.07,which is approaching that required to be im.erceptible to the hum.n *** LC technology is then showcased in an array of different display and im.ging applications,including a dem.nstration of speckle reduction in m.dern vectorial laser-based im.ging.

关键词： polarization speckle crystal

Using accelerom.try to com.are costs of extended m.gration in an arctic herbivore

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Current Zoology 2017年第6期63卷 667-674页

作者： m.tch D. WEEGm.N Stuart BEARHOP Geoff m. HILTON Alyn j. WALSH Larry GRIFFIN Yehezkel S. RESHEFF Ran nathan Anthony DAVID Fox Centre for Ecology and Conservation College of Life and Environmental Sciences University of Exeter Cornwall Campus Penryn TR109EZ UK Wildfowl & Wetlands Trust Slimbridge Gloucester GL2 7BT UK National Parks and Wildlife Service Wexford Wildfowl Reserve North Slob Wexford Ireland Wildfowl & Wetlands Trust Caerlaverock Wetland Centre Eastpark Farm Caerlaverock Durnfriesshire DG1 4RS UK Departm.nt of Ecology Evolution and Behavior The Hebrew University of Jerusalem Givat Ram Jerusalem 91904 Israel Departm.nt of Bioscience Aarhus University Kale Grenavej 14 RФnde DK-8410 Denmark Present address: School of Natural Resources University of Missouri Columbia MO 65211 USA.

Understanding how individuals m.nage costs during the m.gration period is challenging because individuals are difficult to follow between sites; the advent of hybrid Global Positioning System.cceleration （ACC） tracking devices enables researchers to link spatial and tem.oral attributes of avian m.gration with behavior for the first tim. ever. We fitted these devices on m.le Greenland white-fronted geese Anser albifrons flavirostris wintering at 2 sites （Loch Ken, Scotland and Wexford, Ireland） to understand whether birds m.grating further during spring fed m.re on winter- ing and staging areas in advance of m.gration episodes. Although Irish birds flew significantly further （ca. 300 kin） than Scottish birds during spring, their cum.lative hours of m.gratory flight, flight speed during m.gration, and overall dynam.c body ACC （i.e., a proxy for energy expenditure） were not significantly different. Further, Irish birds did not feed significantly m.re or expend significantly m.re energy in advance of m.gration episodes. These results suggest broad individual plasticity in this species, although Scottish birds arriving on breeding areas in Greenland with greater energy stores （because they m.grated less） m.y be better prepared for food scarcity, which m.ght increase their reproductive success.

关键词： avian m.gration cost energy expenditure global positioning system.acceleration tracking devices Greenland whitefronted geese individual decision-m.king proportion of tim. feeding.

First principles insights into oxide/polym.r com.osites: SrTiO_(3) /polyaniline/graphene

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journal of m.terials Science & Technology 2023年第35期166卷 250-260页

作者： nathan D.Wood joshua S.Tse j.nathan m.Skelton David j.Cooke Lisa j.Gillie Stephen C.Parker m.rco m.linari Departm.nt of Chem.cal Sciences School of Applied SciencesUniversity of HuddersfieldHuddersfield HD13DHUK Departm.nt of Chem.stry University of ManchesterManchester M139PLUK Departm.nt of Chem.stry University of BathBath BA27AYUK

A detailed com.utational investigation,based on density functional theory,of the interaction of polyani-line(PANI)and graphene nanoribbons(GNRs)with SrTiO_(3) is *** adsorption of PANI in var-ious oxidation states and co-adsorption with GNRs is found to be therm.dynam.cally ***-sorbed PANI introduces N and C 2p states into the SrTiO_(3) bandgap,while co-adsorption of PANI and GNRs leads to a bridging of the gap and sem.-m.tallic behaviour,thus rendering the electrical properties highly sensitive to the loading of the GNRs/PANI in the *** the lattice dynam.cs of the com.osites predicts a 68-88%reduction in the lattice therm.l conductivity due to reduced phonon group *** together,these findings provide insight into the growing num.er of experim.ntal studies highlighting the enhanced therm.electric perform.nce of oxide-polym.r com.osites and indicate co-adsorption with graphene as a facile direction for future research.

关键词： Polym.r/inorganic com.osites Polyaniline/strontium.titanate/graphene nanoribbon com.osites PANI/GNR/SrTiO_(3)com.osites Therm.electric com.osites Electrical transport Therm.l conductivity1 Introduction

Effect of noncircular orifice plates on the near flow field of turbulent free jets

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Chinese Physics B 2014年第12期23卷 298-306页

作者：徐敏义童杏清岳丹婷张健鹏米建春 nathan G.j. Kalt P.A.m. m.rine Engineering College Dalian Maritime University State Key Laboratory of Turbulence & Com.lex System. College of Engineering Peking University Centre for Energy Technology and School of m.chanical Engineering University of Adelaide

In this paper, we experim.ntally investigate the near-field flow characteristics of turbulent free jets respectively issued from.circular, triangular, diam.nd, rectangular, and notched-rectangular orifice plates into air surroundings. All the orifice plates have identical opening areas or equivalent diam.ters（De） and their aspect ratios（AR） range from.1 to 6.5. Planar particle im.ge velocim.try（PIV） is used to m.asure the velocity field at the sam. Reynolds num.er of Re = 5 × 10^4,where Re = Ue De/ν with Ue being the exit bulk velocity and ν the kinem.tic viscosity of fluid. The m.an and turbulent velocity fields of all the five jets are com.ared in detail. Results show that the noncircular jets can enhance the entrainm.nt rate, reflected by the higher acceleration rates of m.an velocity decay and spread, shorten the length of the unm.xed core,expedite the increase of turbulent intensity com.ared with the circular counterpart shortened unm.xed core, and increase turbulent intensity com.aring to the circular counterpart. Am.ng the five jets, the rectangular jet（AR = 6.5） produces the greatest decay rate of the near-field m.an velocity, postpones the position at which the 鈥榓xis-switching鈥檖henom.non occurs. This supports that axis switching phenom.non strongly depends on jet initial conditions. In addition, the hum. in the centerline variation of the turbulence intensity is observed in the rectangular and triangular jets, but not in the circular jet, nor in diam.nd jet nor in notched-rectangular jet.

关键词： noncircular jet free jet turbulence m.xing axis-switching

The effect of acute aerobic exercise on central arterial stiffness,wave reflections,and hem.dynam.cs in adults with diabetes:A random.zed cross-over design

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journal of Sport and Health Science 2021年第4期10卷 499-506页

作者： Kim.erley L.Way Angela S.Lee Stephen m.Twigg nathan A.johnson Faculty of m.dicine and Health Discipline of Exercise and Sports ScienceUniversity of SydneyLidcombeNSW 2141Australia Charles Perkins Centre University of SydneyCamperdownNSW 2006Australia Boden Collaboration for Obesity NutritionExercise and Eating DisordersUniversity of SydneyCamperdownNSW 2006Australia Faculty of m.dicine and Health Central Clinical SchoolUniversity of SydneyCamperdownNSW 2006Australia Departm.nt of Endocrinology Diabetes CentreRoyal Prince Alfred HospitalSydneyNSW 2050Australia

Background:Individuals with diabetes have greater central arterial stiffness,wave reflections,and hem.dynam.cs,all of which prom.te the accelerated cardiovascular pathology seen in this *** aerobic exercise has been shown to be an effective strategy for reducing central arterial stiffness,wave reflections,and hem.dynam.cs in healthy individuals;however,the effects of acute aerobic exercise in reducing these outcom.s is not well established in people with ***,im.lem.ntation of high-intensity interval exercise(HIIE)has shown superior im.rovem.nts in cardiovascular health outcom.s when com.ared to traditional aerobic ***,the effect of HIIE on the aforem.ntioned outcom.s in people with diabetes is not *** purpose of this study was to(i)describe the central arterial stiffness,wave reflections,and hem.dynam.c responses to a bout of HIIE and m.derate-intensity continuous exercise(m.CE)in adults with diabetes;and(ii)com.are the effects of HIIE and m.CE on the aforem.ntioned ***:A total of 24 adult m.n and wom.n(aged 29-59 years old)with type 1(n=12)and type 2(n=12)diabetes participated in a random.zed cross-over *** participants com.leted the following protocols:(i)HIIE:cycling for 4×4 m.n at 85%-95%of heart rate peak(HR_(peak)),interspersed with 3 m.n of active recovery at 60%-70%HR_(peak);(ii)m.CE:33 m.n of continuous cycling at 60%-70%HR_(peak);and(iii)control(CON):lying quietly in a supine position for 30 ***:A significant group￡tim. effect was found for changes in central systolic blood pressure(F=3.20,p=0.01)with a transient reduction for the HIIE group but not for the m.CE or CON *** was a significant group￡tim. effect for changes in augm.ntation index at a heart rate of 75 beats/m.n(F=2.32,p=0.04)with a decrease following for HIIE and m.CE but not for *** all other m.asures of central arterial stiffness and hem.dynam.cs,no significant changes were observed(p>0.05).Conclusion:A bout of

关键词： Augm.ntation index Central systolic blood pressure Diabetes High-intensity interval exercise

Differential effects of two dom.nant plant species on com.unity structure and invasibility in an old-field ecosystem

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journal of Plant Ecology 2011年第3期4卷 123-131页

作者： Lara Souza jake F.Weltzin nathan j.Sanders Departm.nt of Ecology and Evolutionary Biology University of Tennessee1416 Circle DriveKnoxvilleTN 37996USA USA National Phenology Network National Coordinating Office1955 East 6th StreetTucsonAZ 85719USA

Aim. In this study,we exam.ned the effects of Solidago altissim.(hereafter Solidago)and two species in the genus Verbesina,Verbesina virginica and Verbesina occidentalis(hereafter Verbesina),on the structure of an old-field plant com.unity and establishm.nt by an invasive plant species,Lespedeza cuneata(hereafter Lespedeza).m.thods We rem.ved Solidago,Verbesina and both Solidago and Verbesina from.4m.(-2)plots in an intact old-field com.unity during two growing *** then quantified the effects of these rem.vals on richness,evenness,diversity and com.osition of the subdom.nant plant *** also m.asured the total aboveground biom.ss and the aboveground biom.ss of the subdom.nant *** assess how these rem.vals affected establishm.nt by Lespedeza,we planted 20 seeds in each plot and tracked seedling em.rgence and survival for one growing *** Findings Subdom.nant com.unity evenness and Shannon diversity were higher in plots from.which Solidago and Verbesina were rem.ved relative to control ***,there were no effects of dom.nant species rem.val on species richness or com.osition of the subdom.nant *** aboveground biom.ss was not affected by dom.nant species rem.val,suggesting that the com.unity of subdom.nant species exhibited *** fact,subdom.nant com.unity biom.ss was greater when Solidago,but not Verbesina,was *** availability was also greater in plots where Solidago was rem.ved relative to control plots throughout the growing *** addition,rem.val of dom.nant species,in particular Solidago,indirectly reduced the em.rgence,but not survival,of Lespedeza seedlings by directly prom.ting subdom.nant com.unity *** together,our results suggest that dom.nant old-field plant species affect subdom.nant com.unity structure and indirectly prom.te establishm.nt by Lespedeza.

关键词： com.ensation establishm.nt invasive Lespedeza cuneata Solidago Verbesina

Autologous treatm.nt for ALS with im.lication for broad neuroprotection

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Translational Neurodegeneration 2022年第1期11卷 718-736页

作者： Daehwan Kim.Subin Kim.Ashley Sung Neetika Patel nathan Wong m.chael j.Conboy Irina m.Conboy Departm.nt of Bioengineering and QB3 Institute University of CaliforniaBerkeleyCA 94720USA

Background: Am.otrophic lateral sclerosis (ALS) is characterized by a progressive loss of m.tor neurons (m.s), leading to paralysis, respiratory failure and death within 2-5 years of diagnosis. The exact m.chanism. of sporadic ALS, which com.rises 90% of all cases, rem.in unknown. In fam.lial ALS, m.tations in superoxide dism.tase (SOD1) cause 10% of cases. m.thods: ALS patient-derived hum.n-induced pluripotent stem.cells (ALS hiPSCs, harboring the SOD1AV4 m.tation), were differentiated to m.s (ALS-m.s). The neuroprotective effects of conditioned m.dium.(Cm. of hESCs (H9), wt hiPSCs (WTC-11) and the ALS iPSCs, on m. apoptosis and viability, form.tion and m.intenance of neurites, m.tochon-drial activity and expression of inflam.atory genes, were exam.ned. For in vivo studies, 200 μl of Cm.from.the ALS iPSCs (CS07 and CS053) was injected subcutaneously into the ALS m.del m.ce (transgenic for the hum.n SOD1G93A m.tation). Anim.l agility and strength, m.scle innervation and m.ss, neurological score, onset of paralysis and lifes-pan of the ALS m.ce were assayed. After observing significant disease-m.difying effects, the Cm.was characterized biochem.cally by fractionation, com.arative proteom.cs, and epigenetic screens for the dependence on pluripotency. Cm.of fibroblasts that were differentiated from.the wt hiPSCs lacked any neuroprotective activity and was used as a negative control throughout the studies. Results: The secretom. of PSCs including the ALS patient iPSCs was neuroprotective in the H2O2 m.del. In the m.del with pathogenic SOD1 m.tation, ALS iPSC-Cm.attenuated all exam.ned hallm.rks of ALS pathology, rescued hum.n ALS-m.s from.denervation and death, restored m.tochondrial health, and reduced the expression of inflam.m.tory genes. The ALS iPSC-Cm.also im.roved neuro-m.scular health and function, and delayed paralysis and m.r-bidity in ALS m.ce. Com.ared side by side, cyclosporine (CsA), a m.tochondrial m.m.rane blocker that prevents the leakage of m.tochondri

关键词： Neurodegeneration Am.otrophic lateral sclerosis SOD1 m.tation Pluripotent stem.cells Secretom.

Ecological factors influencing the beneficial endosym.ionts of the hem.ock woolly adelgid (Hem.ptera:Adelgidae)

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Insect Science 2019年第1期26卷 97-107页

作者： Angela m.m.ch Sherilyn j.Harper nathan P.Havill Carol D.von Dohlen Gaelen R.Burke Departm.nt of Entom.logy University of GeorgiaAthensGeorgiaUSA School of Environm.ntal and Forest Sciences University of WashingtonSeattleWashingtonUSA USDA Forest Service Northern Research StationHamdenConnecticutUSA Departm.nt of Biology Utah State UniversityLoganUtahUSA

Bacterial endosym.ionts of sap-sucking insects provide their host with a num. ber of beneficial qualities,including the supply of nutrition,defense against parasitoids, and protection from.heat *** to these bacterial associates can therefore have a negative im.act on the fitness of their insect *** evaluated observational and experi- m.ntal factors regarding the norm.tive hem.ock woolly adelgid (Adelges tsugae Annand) (Hem.ptera:Adelgidae)to help understand the roles of its three recently identified sym.ionts,including under heat stress *** prevalence of ***'s facultafive sym.iont (Serratia sym.iotica)was exam.ned at different spatial scales to determ.ne how variable infection rates are for this *** was no significant difference found in infection rates between adelgids on a tree,within a plot,or within a ***, significantly m.re adelgids in Georgia (95%)had *** com.ared to those in New York (68%).m.crosatellite genotyping of the adelgids found that this difference was m.st likely not the result of a second introduction *** into eastern North *** *** proportions between first and fourth instars showed that sym.iont absence did not affect the ability *** to survive *** of sym. biont densities within each adelgid found that when *** was absent,the density of obligate sym.ionts was significantly *** to heat stress (32.5℃)was not consistently correlated with changes in sym.iont densities over a 4-d ***,we have shown that sym.iont prevalence and densities vary within the broad population of *** in eastern North Am.rica,with potentially significant effects upon the ecology of this im.ortant pest.

关键词： Adelges tsugae Anncindia adelgestsuga bacterial endosym.ionts Serratia sym.iotica Pseudom.nas adelgestsugas