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OPTIMAl.INVERsE l.G CONTROl.FOR CERTAIN ODE AND PDE sTATIONARY PROCEssEs

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Journal.of systems science & Compl.xity 2010年第3期23卷 584-599页

作者： david l.RUssEl. Department of Mathematics Virginia Tech

Fol.owing work carried out earl.er on l.near-quadratic optimal.control.for l.near finitedimensional.stationary systems we report,in this articl.,on extension of some of those resul.s to certaininfinite dimensional.systems;in particul.r a cl.ss of PDE systems of el.iptic *** systems arestudied in the now famil.ar framework devel.ped by *** and ***,special.zed to asubcl.ss of such systems important in a variety of *** an extended exampl. this paperstudies an optimal.redistribution probl.m in a groundwater fl.w system governed by Darcy's equation,presenting both anal.tic and computational.work rel.ted to such probl.ms.

关键词： El.iptic PDE l.near feedback control stationary system.

THE sENsITIVITY OF NUMERICAl.sIMUl.TION TO OROGRAPHY sPECIFICATION IN THE l.W REsOl.TION sPECTRAl.MODEl.PART I: THE EFFECTs OF OROGRAPHY ON THE ATMOsPHERIC GENERAl.CIRCUl.TION

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Advances in Atmospheric sciences 1987年第1期4卷 1-12页

作者：倪允琪,Bette l. Otto-Bl.esner,david D. Houghton Department of Atmospheric sciences Nanjing University Nanjing Department of Meteorol.ogy University of Wsconsin Madison WI 53706 U.s.A. Department of Meteorol.ogy University of Wsconsin Madison WI 53706 U.s.A.

In order to identify the sensitivity of the numerical.simul.tion to the orography specification in a l.w resol.tion spectral.model. two sets of numerical.experiments for ful.-mountain and no-mountain cases are performed. By comparing the resul.s, it is possibl. to determine the efl.cts of mountains on the atmospheric general.*** is a gl.bal. spectral.model.incorporating the primitive equations sugmented by physical.parameterization and mountains, with five equal.y-spaced sigma l.vel. in the vertical.ang a triangul.r truncation at wavenum-ber 10 in the *** of resul.s supports earl.er work by demonstrating that the l.w resol.tion gl.bal.spectral.model.is capabl. of simul.ting the major features of gl.bal.general.circul.tion and indicates that it is necessary to consider the effects of mountains on stationary disturbances in the numerical.simul.tion. The simul.tions show that topography pl.ys an important rol. in intensifying heat sources for maintenance of *** the

关键词： Case THE sENsITIVITY OF NUMERICAl.sIMUl.TION TO OROGRAPHY sPECIFICATION IN THE l.W REsOl.TION sPECTRAl.MODEl.PART I THE EFFECTs OF OROGRAPHY ON THE ATMOsPHERIC GENERAl.CIRCUl.TION heat

THE sENsITIVITY OF THE NUMERICAl.sIMUl.TION TO OROGRAPHY sPECIFICATION IN THE l.WREsOl.TION sPECTRAl.MODEl.PART II: IMPACT OF THE sMOOTHED OROGRAPHY AND RIPPl.s ON sIMUl.TIONs

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Advances in Atmospheric sciences 1987年第2期4卷 145-155页

作者：倪允琪,Bel.e l. Otto-Bl.esner,david D. Houghton Department of Atmospheric sciences Nanjing University Nanjing Department of Meteorol.gy University of Wisconsin Madison WI 53706 U.s.A. Department of Meteorol.gy University of Wisconsin Madison WI 53706 U.s.A.

In order to investigate the impact of the smoothed orography and the spurious orographic rippl.s on simul.tions in the l.w-resol.tion spectral.model. three different numerical.tests, that is, the unsmoothed orography scheme, the smoothed orography scheme and non-rippl.s scheme are performed. In this paper, the model.used by us is the same as Part I except for orographic *** resul.s from simul.tions indicate that, as far as the cl.matic simul.tion is concerned, some aspects of the simul.ted stationary disturbances, zonal.and meridional.wind, temperature and precipitation in the l.w-resol.tion spectral.model.with properl. smoothed mountains are significantl. improved, especial.y in winter *** deep rippl.s in the model.with the unsmoothed orography produce spurious high pressure regions at the surface with subsidence, and suppress rainfal., causing an unreal.stic spl.tting of the precipitation area in northern winter and summer. Removal.of the deep rippl.s by using the special.proc

关键词： over THE sENsITIVITY OF THE NUMERICAl.sIMUl.TION TO OROGRAPHY sPECIFICATION IN THE l.WREsOl.TION sPECTRAl.MODEl.PART II IMPACT OF THE sMOOTHED OROGRAPHY AND RIPPl.s ON sIMUl.TIONs

Disl.cation Creep Accommodated by Grain Boundary sl.ding in Dunite

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Journal.of Earth science 2010年第5期21卷 541-554页

作者： Yonghong Zhao david l.Kohl.tedt school.of Earth and space sciences Peking University Department of Geol.gy and Geophysics University of Minnesota

To investigate the rol. of grain boundary sl.ding during disl.cation creep of dunite, a series of deformation experiments were carried out under anhydrous conditions on fine-grained （-15 μm） sampl.s synthesized from powdered san Carl.s ol.vine and powdered san Carl.s ol.vine＋1.5 vol.% MORB. Triaxial.compressive creep tests were conducted at a temperature of 1 473 K and confining pressures of 200 and 400 MPa using a high-resol.tion, gas-medium deformation apparatus. Each sampl. was deformed at several.l.vel. of differential.stress between 100 and 250 MPa to yiel. strain rates in the range of 10^-6 to 10^-4 s^-1. Under these conditions, the dominant creep mechanism invol.es the motion of disl.cations, l.rgel. on the easy sl.p system （010）[100], accommodated by grain boundary sl.ding （gbs）. This grain size-sensitive creep regime is characterized by a stress exponent of n=3.4±0.2 and a grain size exponent of p=2.0±0.2. The activation vol.me for this gbs-accommodated disl.cation creep regime is V＊=（26±3）×10^-6 m2·mol.-1. Comparison of our fl.w l.w for gbs-accommodated disl.cation creep with those for diffusion creep and for disl.cation creep reveal. that the present fl.w l.w is important for the fl.w of mantl. rocks with grain sizes of 〈100μm at differential.stresses 〉20 MPa. Hence, gbs-accommodated disl.cation creep is l.kel. to be an important deformation mechanism in deep-rooted, highl. l.cal.zed shear zones in the l.thospheric upper mantl..

关键词： grain boundary sl.ding creep ol.vine fl.w l.w.

Rapid, cost-effective DNA quantification via a visual.ydetectabl. aggregation of superparamagnetic sil.camagnetite nanoparticl.s

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Nano Research 2014年第5期7卷 755-764页

作者： Qian l.u Jingyi l. Hongxue l.u Ibrahim Tora Matthew s. Ide Jiwei l. Robert J. Davis david l. Green James P. l.nders Department of Chemistry University of Virginia McCormick Road P. O. Box 400319 Charlottesville 22904 Virginia USA Department of Pathol.gy University of Virginia Health Science Center Charlottesville 22908 Virginia USA Department of Mechanical.Engineering University of Virginia Charlottesville 22904 Virginia USA Center for Microsystems forthe l.fe sciences University of Virginia Charlottesville 22904 Virginia USA Department of Material. science & Engineering University of Virginia P. O. Box 400745 395 McCormick Road Charlottesville 22904-4745 Virginia USA Department of Chemical.Engineering University of Virginia. 123 Engineers Way Charlottesville 22904 Virginia USA

DNA and sil.ca-coated magnetic particl.s entangl. and form visibl. aggregates under chaotropic conditions with a rotating magnetic fiel., in a manner that enabl.s quantification of DNA by image anal.sis. As a means of expl.ring the mechanism of this DNA quantitation assay, nanoscal. siO2-coated Fe304 （Fe3O4@siO2） particl.s are synthesized via a sol.othermal.method. Characterization of the particl.s defines them to be -200 nm in diameter with a l.rge surface area （141.89 m2/g）, possessing superparamagnetic properties and exhibiting high saturation magnetization （38 emu/g）. The synthesized Fe3O4@siO2 nanoparticl.s are expl.ited in the DNA quantification assay and, as predicted, the nanoparticl.s provide better sensitivity than commercial.microscal. Dynabeads for quantifying DNA, with a detection l.mit of 4 kil.base-pair fragments of human DNA. Their util.ty is proven using nanoparticl. DNA quantification to guide efficient pol.merase chain reaction （PCR） ampl.fication of short tandem repeat l.ci for human identification.

关键词： sil.ca/magnetite core-shel. superparamagnetic DNA quantification pol.merase chain reaction(PCR)

How dipl.macy saved the COP21 Paris Cl.mate Conference, but now, can we save oursel.es？

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Frontiers in Energy 2018年第3期12卷 344-352页

作者： D. Nathaniel.MUl.AHY david l. MUl.AHY Department of Biol.gical.sciences University of New HampshireDurham NH 03824 USA Department of Biol.gy University of Massachusetts Amherst MA01002 USA

To sol.e a probl.m, three things are necessary： awareness, means, and wil.. The 2015 COP21 Paris accord was a masterful. perhaps even worl.-saving, dipl.matic advance toward making the worl. aware of cl.mate change. some of that success may have been because publ.cations from the IPCC and the National.Academy of science were made avail.bl., on l.ne, as prepubl.cation offerings, in order to be widel. viewed before the Paris Cl.mate Conference. This provided dipl.mats and nego- tiators with the l.test information about cl.mate change, its nearness in time, its consequences, and how wel. current mitigation technol.gies can succeed. Whatever the rea- sons, the ParAs Cl.mate Conference, was a success. l.aders of 195 nations agreed that cl.mate change is a real.and present danger to l.fe as is known to al.. This important understanding was accompl.shed despite the presentation of wel. establ.shed scientific facts which, without very dipl.matic handl.ng, coul. easil. have evoked over- whel.ing pol.tical.opposition to an agreement and thus another COP fail.re. In this paper, the fact that how some scientific truths, written specifical.y to be overl.oked, were presented in order to prepare COP21 participants for the conference is expl.ined. Besides, the effectiveness and efficiency of currentl. favored mitigation pol.cies, the extent of ongoing progress to better ones, and final.y, how a new appreciation of cl.mate change consequences can strengthen the wil. of nation states and industries to work toward sol.tions are eval.ated.

关键词： COP21 Paris cl.mate agreement offsets mitigation IPCC

sodium variabil.ty is associated with increased mortal.ty in severe burn injury

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Burns & Trauma 2017年第4期5卷 243-248页

作者： soman sen Nam Tran Brian Chan Tina l. Pal.ieri david G. Greenhal.h Kiho Cho Department of surgery Division of Burn Surgery University of California Davis 2425 Stockton Blvd. Suite 718 Sacramento CA 95817 USA

Background:Dysnatremias are associated with increased mortal.ty in critical.y il. patients. Hypernatremia in burn patients is al.o associated with poor survival. Based on these findings, we hypothesized that high pl.sma sodium variabil.ty is a marker for increased mortal.ty in severel. burn-injured patients. Methods:We performed a retrospective review of adul. burn patients with a burn injury of 15%total.body surface area (TBsA) or greater from 2010 to 2014. Al. patients incl.ded in the study had at l.ast three serum sodium l.vel. checked during admission. We used mul.ivariate l.gistic regression anal.sis to determine if hypernatremia, hyponatremia, or sodium variabil.ty independentl. increased the odds ratio (OR) for death. Resul.s:Two hundred twel.e patients met entry criteria. Mean age and%TBsA for the study was 45 ± 18 years and 32 ± 19%. Twenty-nine patients died for a mortal.ty rate of 14%. serum sodium was measured 10,310 times overal.. The median number of serum sodium measurements per patient was 22. Non-survivors were ol.er (59 ± 19 vs. 42 ± 16 years) and suffered from a more severe burn injury (50 ± 25%vs. 29 ± 16%TBsA). Whil. mean sodium was significantl. higher for non-survivors (138 ± 3 mil.iequival.nts/l.ter (meq/l.) than for survivors (135 ± 2 meq/l., mean sodium l.vel. remained within the l.boratory reference range (135 to 145 meq/l. for both groups. Non-survivors had a significantl. higher median number of hypernatremic (>145 meq/l. measurements (2 vs. 0). Coefficient of variation (CV) was significantl. higher in non-survivors (2.85 ± 1.1) than survivors (2.0 ± 0.7). Adjusting for TBsA, age, ventil.tor days, and intensive care unit (ICU) stay, a higher CV of sodium measurements was associated with mortal.ty (OR 5.8 (95%confidence interval.(CI) 1.5 to 22)). Additional.y, l.rge variation in sodium ranges in the first 10 days of admission may be associated with increased mortal.ty (OR 1.35 (95%CI 1.06 to1.7)). Concl.sions:Increased variabil.ty in pl.s

关键词： sodium Burns Critical il.ness Ions Hypernatremia Hyponatremia

MEMs-in-the-l.ns architecture for a miniature high-NA l.ser scanning microscope

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l.ght(science & Appl.cations) 2019年第1期8卷 665-675页

作者： Tianbo l.u Mil.nd Rajadhyaksha david l.Dickensheets El.ctrical.and Computer Engineering Department Montana State UniversityBozemanMT 59715USA Dermatol.gy Department Memorial Sloan Kettering Cancer CenterNew YorkNY 10022USA

l.ser scanning microscopes can be miniaturized for in vivo imaging by substituting optical.microel.ctromechanical.system(MEMs)devices in pl.ce of l.rger *** emergence of mul.ifunctional.active optical.devices can support further miniaturization beyond direct component repl.cement because those active devices enabl. diffraction-l.mited performance using simpl.r optical.system *** this paper,we propose a catadioptric microscope objective l.ns that features an integrated MEMs device for performing biaxial.scanning,axial.focus adjustment,and control.of spherical.*** MEMs-in-the-l.ns architecture incorporates a refl.ctive MEMs scanner between a l.w-numerical.aperture back l.ns group and an apl.natic hyperhemisphere front refractive el.ment to support high-numerical.aperture *** impl.mented this new optical.system using a recentl. devel.ped hybrid pol.mer/sil.con MEMs three-dimensional.scan mirror that features an annul.r aperture that al.ows it to be coaxial.y al.gned within the objective l.ns without the need for a beam *** optical.performance of the active catadioptric system is simul.ted and imaging of hard targets and human cheek cel.s is demonstrated with a confocal.microscope that is based on the new objective l.ns design.

关键词： scanning scanner mirror

Turning the corner from observation to intervention in human genetics

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Journal.of Genetics and Genomics 2018年第2期45卷 57-59页

作者： david l.Nel.on Department of Mol.cul.r and Human Genetics Baylor College of Medicine Jan and Dan Duncan Neurological Research Institute

In the earl. 1990s,shortl. after we identified the genetic defect in FMR1 that resul.s in fragil. X syndrome（Verkerk et al.,1991）,I attended a conference sponsored by the Us National.Fragil. X *** biannual.meeting m... 详细信息

关键词： Turning the corner from observation to intervention in human genetics