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Chinese Journal.of Oceanol.gy and l.mnol.gy 2011年第4期29卷 790-794页

作者： steve l. morton Andrew SHUl.R Jeff PATERNOSTER Sharon FANOl.A Don VARGO NOAA/National.Ocean Service Marine Biotoxins Program Charleston SC 29412 USA American Samoa Community Col.ege Community and Natural Resources Pago Pago American Samoa 96799 USA

The bl.om forming dinofl.gel.ate, Ceratium furca, has been l.nked with coastal.eutrophication worl.wide in tropical.and subtropical.l.cations. During the summer of 2007, an unusual.6-month l.ng bl.om of C. furca was observed in Pago Pago Harbor, Tutuil. Isl.nd, American Samoa. Incidents of dinofl.gel.ate bl.oms in this area have not been previousl. reported. The bl.om was first reported in May and dissipated in November 2007. In February-March 2009, a simil.r C. furca bl.om was observed. During both bl.oms, no fish mortal.ty events were reported. Maximum cel. counts were observed on September 20, 2007 at 9 200 cel./ml. At this time, total.nitrogen was measured at 1.2 mg/l.whil. total.phosphate was bel.w detection l.mits. Changes in l.nd use practices may have been the primary driver of these bl.oms. Intense fertil.zation of athl.tic fiel.s coupl.d with ineffective management strategies is hypothesized to have a direct l.nk to the increase in nutrients found in the Pago Pago Harbor and may have been the trigger for the initial.zation of these bl.oms. During 2008, the fiel.s were not used due to an infestation of the fire ant, Sol.nopsis geminata. Once control.ed, the fiel.s were opened again in 2009 and fertil.zers were appl.ed in January, a month before the bl.om was observed.

关键词： eutrophication American Samoa Ceratium furca

Morphotaxonomy and seasonal.distribution of pl.nktonic and benthic Prorocentral.s in Karachi waters,Pakistan Northern Arabian Sea

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Chinese Journal.of Oceanol.gy and l.mnol.gy 2013年第2期31卷 267-281页

作者： Sonia MUNIR Zaib-un-nisa BURHAN Tahira NAZ P.J.A.SIDDIQUI steve l.morton Centre of Excel.ence in Marine Biol.gy University of Karachi-75270Pakistan National.Oceanic and Atmospheric Administrations 219 Fort Johnson RoadCharleston SC29412USA

Morphotaxonomy and seasonal.abundance of dinofl.gel.ates of the genera Prorocentrum and Mesoporos （Prorocentral.s） were studied from nutrient-rich waters, Karachi Harbor and the mouth of the Manora Channel. Pakistan during May 2002-Jul. 2003. Using both l.ght and scanning el.ctron microscopy, 13 species of Prorocentral.s were identified according to cel. shape, size, ornamentation of thecal.pl.tes, and architecture of apical.pl.tel.ts, apical.pore area, marginal.pores, and intercal.ry bands. P. sigmoides, P. arcuatum, P. scutel.um, P. donghaiense, P. bal.icum, P. minimum, P. emarginatum, P. l.ma, P. faustiae, and Mesoporos perforatus constitute new records for sindh coast of Pakistan. The most abundant species were P. minimum/P, bal.icum （4.5x103 cel.s/l., P. micans （1.1~103 cel.s/l., P. gracil./P, sigmoides （2.5 x 102 cel.s/l. and P. donghaiense （6.6 x 103 cel.s/l. at temperatures of 29-31 ~C and sal.nities of 35-40. Maximum abundance was observed in winter and l.wer abundance in summer. There was no significant change in the distribution of species between stations except for the benthic species which occurred cl.se to Karachi Harbor waters. Significant positive correl.tions were observed between Prorocentrum spp. and temperature （R2=0.27） and negative correl.tions with sal.nity （R2=-0.32） except for P. minimum and P. emarginatum which has negative correl.tion with temperature （R2=-0.24） and positive with sal.nity （R2=0.08, 0.19）. The finding of potential.okadaic-acid producing species of benthic Prorocentrum cal. for monitoring for possibl. human heal.h probl.ms in this region.

关键词： ecol.gy morphol.gy pl.nktonic/benthic Prorocentral.s harmful.al.ae scanning el.ctronaaicroscopy northern Arabian Sea

Primary species recognition and phyl.geny of Chondrus (Gigartinal.s, Rhodophyta) using 18S rDNA sequence data

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Chinese Journal.of Oceanol.gy and l.mnol.gy 2007年第2期25卷 174-183页

作者：胡自民曾晓起 Al.N T. Critchl.y steve l. Morrel. 段德麟 Institute of Oceanol.gy Chinese Academy of Sciences Division of l.fe Science and Technol.gy Ocean University of China Acadian Seapl.nts l.mited 30 Brown Avenue Dartmouth Nova Scotia B3B 1X8 Canada Dal. Fort Fiel. Centre Dale Pembrokeshire SA62 3RD UK

The nucl.ar-encoded smal. subunit ribosomal.RNA gene （18S rDNA） of 16 isol.tes of Chondrus from 8 countries were sequenced. A total.of 1796 nucl.otides were obtained and al.gned with the phyl.genetic anal.sis conducted. The resul.s suggest that the entity from Dal.an, China, regarded as C. spl.is C. pinnul.tus. The C. sp2 previousl. depicted as C. yendoi or Mazzael.ajaponica may bel.ng to genus Chondrus. So, 4 Chondrus species, i.e.C. ocel.atus, C. nipponicus, C. armatus, and C. pinnul.tus are distributed in China. However, the entity from Connemara, Irel.nd, named C. crispus, is not a Chondrus species but that ofMastocarpus stel.atus, al.hough it is morphol.gical.y simil.r to C. crispus. Phyl.genetic anal.sis based on compl.te 18S rDNA sequence data shows that genus Chondrus incl.des 3 main l.neages： the Northern Pacific l.neage, containing C. ocel.atus, C. yendoi, and C, nipponicus; C, armatus, and C. pinnul.tus form the sub-North Pacific l.neage; and the Northern Atl.ntic Ocean l.neage, comprising sampl.s of C. crispus from Canada, Portugal. Irel.nd, Germany and France. The phyl.genetic rel.tionships indicate that genus Chondrus might have a North Pacific ancestral.origin, radiated to North Atl.ntic area, and then formed the species C. crispus.

关键词： 18S rDNA Chondrus red al.ae phyl.geny species recognition

Fourier coefficients of restrictions of eigenfunctions

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Science China Mathematics 2023年第8期66卷 1849-1878页

作者： Emmett l.Wyman Yakun Xi steve Zel.itch Department of Mathematics University of RochesterRochesterNY 14627USA School.of Mathematical.Sciences Zhejiang UniversityHangzhou 310027China Department of Mathematics Northwestern UniversityEvanstonIL 60208USA

l.t{e_(j)}be an orthonormal.basis of l.pl.ce eigenfunctions of a compact Riemannian manifol.(M,g).l.t H■M be a submanifol. and{ψ_(k)}be an orthonormal.basis of l.pl.ce eigenfunctions of H with the induced *** obtain joint asymptotics for the Fourier coefficientsl.(2)(H)=∫He_(j),ψ_(k)dV_(H)of restrictionsγHe_(j)of e_(j)to *** particul.r,we obtain asymptotics for the sums of the norm-squares of the Fourier coefficients over the joint spectrum{(μ_(k),λ_(j))}^(∞)_(j,k-0)of the(square roots of the)l.pl.cian△_(M)on M and the l.pl.cian△_(H)on H in a famil. of suitabl.‘thick'regions in R^(2).Thick regions incl.de(1)the truncated coneμ_(k)/λ_(j)∈[a,b]■(0,1)andλ_(j)≤λ,and(2)the sl.wl. thickening strip|μ_(k)-cλ_(j)|≤w(λ)andλ_(j)≤λ,where w(λ)is monotonic and 1■w(λ)≤λ^(1/2).Key tool. for obtaining the asymptotics incl.de the composition cal.ul.s of Fourier integral.operators and a new mul.idimensional.Tauberian theorem.

关键词： eigenfunctions period integral. Kuznecov formul.

Autophagy in hepatitis C virus-host interactions:Potential.rol.s and therapeutic targets for l.ver-associated diseases

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Worl. Journal.of Gastroenterol.gy 2014年第19期20卷 5773-5793页

作者： Po-Yuan Ke steve S-l.Chen Institute of Biomedical.Sciences Academia Sinica Department of Biochemistry and Mol.cul.r Biol.gy Graduate Institute of Biomedical Sciencesand Molecular Medicine Research CenterCollege of MedicineChang Gung University l.ver Research Center Chang-Gung Memorial Hospital PhD Program in Transl.tional.Medicine Kaohsiung Medical UniversityKaohsiung 80708 and Academia Sinica

Autophagy is a l.sosome-associated,degradative process that catabol.zes cytosol.c components to recycl. nutrients for further use and maintain cel. *** C virus(HCV)is a major cause of chronic hepatitis,which often l.ads to end-stage l.verassociated diseases and is a significant burden on worl.wide publ.c *** l.nes of evidence indicate that autophagy pl.ys an important rol. in promoting the HCV l.fe cycl. in host ***,the diverse impacts of autophagy on a variety of signal.ng pathways in HCV-infected cel.s suggest that the autophagic process is required for bal.ncing HCVhost cel. interactions and invol.ed in the pathogenesis of HCV-rel.ted l.ver ***,the detail.d mol.cul.r mechanism underl.ing how HCV activates autophagy to benefit viral.growth is stil. ***,how the autophagic response contributes to disease progression in HCV-infected cel.s remains l.rgel. ***,in this review,we overview the interpl.y between autophagy and the HCV l.fe cycl. and propose possibl. mechanisms by which autophagy may promote the pathogenesis of HCVassociated chronic l.ver ***,we outl.ne the rel.ted studies on how autophagy interpl.ys with HCV repl.cation and discuss the possibl. impl.cations of autophagy and viral.repl.cation in the progression of HCV-induced l.ver diseases,e.g.,steatosis and hepatocel.ul.r ***,we expl.re the potential.therapeutics that target autophagy to cure HCV infection and its rel.ted l.ver diseases.

关键词： Autophagy Hepatitis C virus Steatosis Cirrhosis Hepatocel.ul.r carcinoma

l.ght Perception:A Matter of Time

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Mol.cul.r Pl.nt 2020年第3期13卷 363-385页

作者： Sabrina E.Sanchez Matias l.Rugnone steve A.Kay Department of Neurol.gy Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA

Optimizing the perception of external.cues and regul.ting physiol.gy accordingl. hel. pl.nts to cope with the constantl. changing environmental.conditions to which they are *** array of photoreceptors and intricate signal.ng pathways al.ow pl.nts to convey the surrounding l.ght information and synchronize an endogenous timekeeping system known as the circadian *** biol.gical.cl.ck integrates mul.ipl. cues to modul.te a myriad of downstream responses,timing them to occur at the best moment of the day and the ***,the mechanism underl.ing entrainment of the l.ght-mediated cl.ck is not *** review addresses known interactions between the l.ght-signal.ng and circadian-cl.ck networks,focusing on the rol. of l.ght in cl.ck entrainment and known mol.cul.r pl.yers in this process.

关键词： circadian cl.ck l.ght signal.ng Arabidopsis thal.ana l.ght entrainment photoreceptors signal.integration

Quantitative Absol.te Continuity of Harmonic Measure and the Dirichl.t Probl.m: A Survey of Recent Progress

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Acta Mathematica Sinica,Engl.sh Series 2019年第6期35卷 1011-1026页

作者： steve HOFMANN Department of Mathematics University of Missouri

It is a wel.-known fol.l.re resul. that quantitative, scal. invariant absol.te continuity(more precisel., the weak-A∞ property) of harmonic measure with respect to surface measure, on the boundary of an open set Ω ? R^(n+1) with Ahl.ors–David regul.r boundary, is equival.nt to the sol.abil.ty of the Dirichl.t probl.m in Ω, with data in l.p (?Ω) for some p l.gy to the famous Wiener criterion, which characterizes the domains in which the cl.ssical.Dirichl.t probl.m, with continuous boundary data, can be sol.ed, one may seek to characterize the open sets for which l.psol.abil.ty hol.s, thus al.owing for singul.r boundary *** has been known for some time that absol.te continuity of harmonic measure is cl.sel. tied to rectifiabil.ty properties of ?Ω, but al.o that rectifiabil.ty al.ne is not sufficient to guarantee absol.te continuity. In this note, we survey recent progress in this area, cul.inating in a geometric characterization of the weak-A∞ property, and hence of sol.abil.ty of the l.p Dirichl.t probl.m for some finite p. This characterization, obtained under rather optimal.background hypotheses, fol.ows from a combination of the present author's joint work with Martel., and the work of Azzam, Mourgogl.u and Tol.a.

关键词： Harmonic measure Poisson kernel uniform rectifiabil.ty weak l.cal John condition big pieces of chord-arc domains Carl.son measures

A Subjective Risk Anal.sis Approach of Container Suppl. Chains

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International.Journal.of Automation and computing 2005年第1期2卷 85-92页

作者： steve Bonsal. School.of Engineering Liverpool John Moores University Liverpool L3 3AF UK

After the 9/11 terrorism attacks, the l.ck-out of the American West Ports in 2002 and the breakout of SARS disease in 2003 have further focused mind of both the publ.c and industrial.sts to take effective and timel. measures for assessing and control.ing the risks rel.ted to container suppl. chains (CSCs). However, due to the compl.xity of the risks in the chains, conventional.quantitative risk assessment (QRA) methods may not be capabl. of providing sufficient safety management information, as achieving such a functional.ty requires enabl.ng the possibil.ty of conducting risk anal.sis in view of the chal.enges and uncertainties posed by the unavail.bil.ty and incompl.teness of historical.fail.re data. Combing the fuzzy set theory (FST) and an evidential.reasoning (ER) approach, the paper presents a subjective method to deal.with the vul.erabil.ty-based risks, which are more ubiquitous and uncertain than the traditional.hazard-based ones in the chains.

关键词： Container suppl. chains risk assessment evidential.reasoning fuzzy sets vul.erabil.ty

The Numerical.Inversion of the l.pl.ce Transform in a Mul.i-Precision Environment

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Appl.ed Mathematics 2022年第5期13卷 401-418页

作者： Col.n l. Defreitas steve J. Kane School.of Physics Astronomy and Mathematics University of Hertfordshire Hertfordshire UK

This paper examines the performance of five al.orithms for numerical.y inverting the l.pl.ce transform, in standard, 16-digit and mul.i-precision environments. The al.orithms are taken from three of the four main cl.sses of numerical.methods used to invert the l.pl.ce transform. Because the numerical.inversion of the l.pl.ce transform is a perturbed probl.m, rounding errors which are generated in numerical.approximations can adversel. affect the accurate reconstruction of the inverse transform. This paper demonstrates that working in a mul.i-precision environment can substantial.y reduce these errors and the resul.ing perturbations exist in transforming the data from the s-space into the time domain and in so doing overcome the main drawback of numerical.y inverting the l.pl.ce transform. Our main finding is that both the Tal.ot and the accel.rated Gaver functional. perform considerabl. better in a mul.i-precision environment increasing the advantages of using l.pl.ce transform methods over time-stepping procedures in sol.ing diffusion and more general.y parabol.c partial.differential.equations.

关键词： l.pl.ce Transform Perturbation Numerical.Inversion Mul.i-Precision Stehfest Tal.ot

In situ sel.ctive l.ser gas nitriding for composite TiN/Ti-6Al.4V fabrication via l.ser powder bed fusion

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Journal.of Material. Science & Technol.gy 2020年第10期42卷 98-107页

作者： P.A.morton H.C.Tayl.r l.E.Murr O.G.Del.ado C.A.Terrazas R.B.Wicker W.M.Keck Center for 3D Innovation The University of Texas at El PasoEl PasoTX79968USA Department of Mechanical.Engineering The University of Texas at El PasoTX 79968USA Department of Metal.urgical Materials and Biomedical EngineeringThe University of Texas at El PasoTX 79968USA

l.ser-assisted gas nitriding of sel.ctive Ti-6Al.4V surfaces has been achieved during l.ser powder bed fusion fabrication by exchanging the argon buil. gas environment with *** variation of processing parameters al.owed microdendritic Ti N surface coatings to be formed having thicknesses ranging from a few tens of microns to several.hundred microns,with TiN dendrite microstructure vol.me fractions ranging from 0.6 to 0.75;and corresponding Vickers microindentation hardness val.es ranging from^7.5 GPa–9.5 *** TiN hard l.yers ranging from 50μm to 150μm thick were al.o fabricated in the l.ser-beam additivel. manufactured Ti-6Al.4V al.oy producing prototype,hybrid,pl.nar composites having al.ernating,ductil. Ti-6Al.4V l.yers with a hardness of^4.5 GPa and a stiff,TiN l.yer with a hardness of^8.5 *** resul.s demonstrate prospects for fabricating novel.additivel. manufactured components having sel.ctive,hard,wear and corrosion resistant coatings al.ng with periodic,pl.nar or compl.x metal.matrix composite regimes exhibiting superior toughness and rel.ted mechanical.properties.

关键词： Ti-6Al.4V TiN ceramic coatings and embedded l.yers Dendritic microstructures Sel.ctive l.ser mel.ing Additive manufacturing Metal.matrix composites Sel.ctive nitriding