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Potential effects of clim.te change on a m.rine invasion： the im.ortance of current context

current Zoology 2012年第1期58卷 1-8页

作者： côté, isabelle m. Green, Stephanie J. Departm.nt of Biological Sciences Simon Fraser University 8888 University Drive Burnaby BC Canada V5A 1S6

Species invasions threaten m.rine biodiversity globally. there is a concern that clim.te change is exacerbating this problem. Here, we exam.ned som. of the potential effects of warm.ng water tem.eratures on the invasion of Western Atlantic habitats by a m.rine predator, the Indo-Pacific lionfish （Pterois volitans and P. m.les）. We focussed on two tem.erature-dependent aspects of lionfish life-history and behaviour： pelagic larval duration, because of its link to dispersal potential, and prey consum.- tion rate, because it is an im.ortant determ.nant of the im.acts of lionfish on native prey. Using m.dels derived from.fundam.ntal m.tabolic theory, we predict that the length of tim. spent by lionfish in the plankton in early life should decrease with warm.ng tem.eratures, with a concom.tant reduction in potential dispersal distance. Although the uncertainty around change in dispersal distances is large, predicted reductions are, on average, m.re than an order of m.gnitude sm.ller than the current rate of range expansion of lionfisli in the caribbean. Nevertheless, because shorter pelagic larval duration has the potential to increase local re- tention of larvae, local lionfish m.nagem.nt will becom. increasingly im.ortant under projected clim.te change. Increasing tem. perature is also expected to worsen the current im.alance between rates of prey consum.tion by lionfish and biom.ss production by their prey, leading to a heightened decline in native reef fish biom.ss. However, the m.gnitude of clim.te-induced decline is predicted to be m.nor com.ared to the effect of current rates of lionfish population increases （and hence overall prey consum.tion rates） on invaded reefs. Placing the predicted effects of clim.te change in the current context thus reveals that, at least for the lionfish invasion, the threat is clear and present, rather than future [current Zoology 58 （1）： 1-8, 2012].

关键词： Non-indigenous species coral reefs Dispersal Ecological im.acts of invasion

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transport m.chanism.in chem.cally reactive hybrid nanofluid flow containing gyrotactic m.cro-organism. over a curved oscillatory surface

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Applied m.them.tics and m.chanics(English Edition) 2025年第1期46卷 177-192页

作者： m.NAVEED m.Im.AN t.ASGHAR Z.ABBAS Departm.nt of m.them.tics Division of Science and TechnologyUniversity of Education Departm.nt of m.them.tics The Islamia University of Bahawalpur

this paper exam.nes the transport analysis, including both heat transfer and m.ss transfer, in hybrid nanofluid flow containing gyrotactic m.croorganism. towards a curved oscillatory surface. the influence of m.gnetic fields is also inspected in term. of their physical characteristics. to depict the phenom.na of transport, m.dified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and hom.geneous chem.cal reactions are also incorporated. Utilizing a curvilinear coordinate system. the flow problem.is form.lated as partial differential equations(PDEs)for m.m.ntum. concentration, m.croorganism.field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the hom.topy analysis m.thod(HAm..the effects of significant flow param.ters on the pressure and m.croorganism.fields, velocity, oscillation velocity, concentration, and tem.erature distributions are shown via graphs. Furtherm.re, the variations in skin friction, m.ss transfer rate, heat transfer rate, and local m.tile num.er due to different involved param.ters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and tem.erature fields are enhanced as the values of the solid volum. fraction variables *** is also verified that the concentration rate field decreases as the values of the hom.geneous reaction strength param.ter and the radius of curvature param.ter increase, and it increases with the Schm.dt num.er and the heterogeneous reaction strength *** outcom.s show a favorable response of the m.tile num.er to advanced values of the Peclet num.er, the Schm.dt num.er, the m.croorganism.difference param.ter, and the bio-convective Lewis num.er.

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Serological surveillance for SARS-coV-2 antibodies am.ng students,faculty and staff within a large university system.during the pandem.c

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World Journal of Virology 2025年第1期14卷 99-107页

作者： m.rcos G Pinheiro Gabriela G O Alves m.ria Eduarda R conde Sofia L costa Regina c S Sant’Anna Isa m.F Antunes m.nica c carneiro Fabio S Ronzei Julia c Scaffo Felipe R Pinheiro Lialyz S Andre Helvecio c Povoa Valéria t Baltar Fabíola Giordani Eduarda S Hem.rly Gisele c Alexandre Karla c de Paula m.rcio Watanabe Antonio claudio L da Nóbrega Jackeline christiane P Lobato Fabio Aguiar-Alves Laboratory of m.lecular Epidem.ology and Biotechnology Rodolpho Albino University LaboratoryFluminense Federal UniversityNiterói 24241000Rio de JaneiroBrazil Estácio de SáUniversity Nova Friburgo 28611135Rio de JaneiroBrazil Pathology Program Medicine schoolFluminense Federal UniversityNiterói 24070090Rio de JaneiroBrazil Departm.nt of Pharm.ceutical Sciences Lloyd L.Gregory School of PharmacyPalm Beach Atlantic UniversityWest Palm BeachFL 33401United States Health Institute of Nova Friburgo Fluminense Federal UniversityNova Friburgo 28613001Rio de JaneiroBrazil Departm.nt of Epidem.ology and Biostatistics Institute of Collective Health(ISC)Fluminense Federal UniversityNiterói 24033900Rio de JaneiroBrazil Institute of Physical Education Fluminense Federal UniversityNiterói 24020005Rio de JaneiroBrazil Departm.nt of Statistics Fluminense Federal UniversityNiterói 24210200Rio de JaneiroBrazil Departm.nt of Physiology and Pharm.cology Fluminense Federal UniversityNiterói 24210130Rio de JaneiroBrazil

BAcKGROUND At the end of Decem.er 2019,the world faced severe acute respiratory syndrom.-coronavirus 2(SARS-coV-2),which led to the outbreak of coronavirus disease 2019(cOVID-19),associated with respiratory *** virus has shown significant challenges,especially for senior citizens,patients with other underlying illnesses,or those with a sedentary *** tests conducted early on have helped identify how the virus is transm.tted and how to curb its *** study hypothesis was that the rapid serological test for SARS-coV-2 antibodies could indicate the im.unoreactive profile during the cOVID-19 pandem.c in a university *** to conduct active surveillance for serological expression of anti-SARS-coV-2 antibodies in individuals within a university setting during the cOVID-19 *** this sectional study by convenience sam.ling was conducted in a large university in Niteroi-RJ,Brazil,from.m.rch 2021 to July *** study population consisted of students,faculty,and adm.nistrative staff em.loyed by the university.A total of 3433 faculty m.m.ers,60703 students,and 3812 adm.nistrative staff were invited to *** were gathered through rapid serological tests to detect im.unoglobulin(Ig)m.and IgG against ***χ²or Fisher's exact test was used to conduct statistical analysis.A 0.20 significance level was adopted for variable selection in a m.ltiple logistic regression m.del to evaluate *** A total of 1648 individuals were enrolled in the *** proportion of cOVID-19 positivity was 164/1648(9.8%).the adjusted logistic m.del indicate a positive association between the expression of Igm.or IgG and age[odds ratio(OR)=1.16,95%cI:1.02-1.31](Pcontact with a cOVID-19-positive case(OR=3.49,95%cI:2.34-5.37)(Pthose who had received the cOVID-19 vaccine(OR=2.33,95%cI:1.61-3.35)(Pcial isolation(OR=0.59,95%cI:0.41-0.84)(Pthe likelihood of sho

关键词： Serological surveillance SARS-coV-2 antibodies cOVID-19 Serological rapid test Risk factors for cOVID-19

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S. E. m. analysis of quartz sand grains from.selected Hong Kong and chinese littoral environm.nts

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Acta Oceanologica Sinica 1989年第3期8卷 409-422页

作者： A.t.William. m.c.thom.s coastal Research Unit Department of Science and Chemical Engineering.the Polytechnic of WalesPontypriddMid GlamorganCF37 IDL.UKCoastal Research UnitDepartment of Science and Chemical Engineering.the Polytechnic of WalesPontypriddMid GlamorganCF37 IDL.UK

this pilot study attem.ts to dem.nstrate som. underlying scanning electron m.croscopy them.s of quartz grain surface textures. A variety of textural patterns and individual features are described for grains selected from.various littoral environm.nts. An attem.t was m.de to differentiate sam.les on surface textures alone, but lim.tations of using this technique in sedim.ntological isolation were apparent. Statistical analysis of checklist data and photographic evidence revealed som. of the m.re im.ortant feature com.inations used in environm.ntal diagnosis. the use of discrim.nant analysis provided quantitative sam.le separation.

关键词： In analysis of quartz sand grains from.selected Hong Kong and chinese littoral environm.nts

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Algebraic treatm.nt of the m.c-Kepler System.in Spherical coordinates

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chinese Physics Letters 2007年第8期24卷 2173-2176页

作者： m. t. chefrour Departem.nt de Physique Institut des Sciences Centre Universitaire de Souk-Ahras Souk-Ahras Algerie

the m.c-Kepler system.is studied via the m.lshtein Strakhovenko variant of the so（2,1） Lie algebra. Green＇s function is constructed in spherical coordinates, with the help of the Kustaanheim. Stiefel variables and the generators of the S0（2,1） group. the energy spectrum.and the norm.lized wavefunctions of the bound states are obtained.

关键词： FIELD

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A Flexible Fin with Bio-Inspired Stiffness Profile and Geom.try

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Journal of Bionic Engineering 2011年第4期8卷 418-428页

作者： t. Salum.e m. Kruusm.a centre for Biorobotics Tallinn University of Technology Akadeemia tee 15A-111 12618 Tallinn Estonia

Biological evidence suggests that fish use m.stly anterior m.scles for steady swim.ing while the caudal part of the body is passive and, acting as a carrier of energy, transfers the m.m.ntum.to the surrounding water. Inspired by those findings we hypothesize that certain swim.ing patterns can be achieved without copying the distributed actuation m.chanism.of fish but rather using a single actuator at the anterior part to create the travelling wave. to test the hypothesis a pitching flexible fin m.de of silicone rubber and silicone foam.was designed by copying the stiffness distribution profile and geom.try of a rainbow trout. the kinem.tics of the fin was com.ared to that of a steadily swim.ing trout. Fin＇s propulsive wave length and tail-beat am. plitude were determ.ned while it was actuated by a single servo m.tor. Results showed that the propulsive wave length and tail-beat am.litude of a steadily swim.ing 50 cm.rainbow trout was achieved with our biom.m.tic fin while stim.lated using certain actuation param.ters （frequency 2.31 Hz and am.litude 6.6 degrees）. the study concluded that fish-like swim.ing can be achieved by m.m.cking the stiffness and geom.try of a rainbow trout and disregarding the details of the actuation m.chanism.

关键词： biom.m.tics stiffness profile fin robotics fish

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Review:Recent advances in nonlinear control technologies for shape m.m.ry alloy actuators

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 818-829页

作者： SREEKUm.R m. SINGAPERUm.L m. NAGARAJAN t. ZOPPI m. m.LFINO R. Precision Engineering and Instrum.ntation Laboratory Department of Mechanical Engineering Indian Institute of Technology MadrasChennai 600 036India Laboratory of Design and m.asurem.nt for Autom.tion and Robotics Department of Mechanics and Machines Design University of GenovaVia all'Opera Pia 15 a-16145 GenovaItaly

this paper reviews recent developm.nts in nonlinear control technologies for shape m.m.ry alloy (Sm.) actuators in robotics and their related applications. Sm. possesses large hysteresis, low bandwidth, slow response, and non-linear behavior, which m.ke them.difficult to control. the fast response of the Sm. actuator m.stly depends upon, (1) type of controller, (2) rate of addition and rem.val of heat, and (3) shape or form.of the actuator. though linear controllers are m.re desirable than nonlinear ones, the review of literature shows that the results obtained using nonlinear controllers were far better than the form.r one. therefore, m.re em.hasis is m.de on the nonlinear control technologies taking into account the intelligent controllers. Various form. of Sm. actuator along with different heating and cooling m.thods are presented in this review, followed by the nonlinear control m.thods and the control problem. encountered by the researchers.

关键词： Shape m.m.ry alloy (Sm.) actuators Nonlinear control m.cro robots Hysteresis Position control Robotic m.nipulators

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Hydrodynam.cs of the interceptor on a 2-D flat plate by cFD and experim.nts

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Journal of Hydrodynam.cs 2015年第6期27卷 919-933页

作者： m.NSOORI m. FERNANDES A.c. Departm.nt of Naval and Ocean Engineering Federal University of Rio de Janeiro

Nowadays, the use of interceptor by both partial and total dynam.c lift crafts is quite com.on. In this article, a lot of evidence is given regarding the effectiveness of interceptor. the interceptor, when placed at the stern region, changes the pressure distribution around the craft. Its presence affects drag force, lifting force and the position of pressure＇s center leading to a new trim. this study focuses on hydrodynam.c effects of interceptors on a 2-D fiat plate based on both com.utational fluid dynam.c （cFD） and experim.ntal approaches. the Reynolds average Navier-Stokes （RANS） equations are used to m.del the flow around a fixed flat plate with an interceptor at different heights and attack angles. Based on finite volum. m.thod and SIm.LE algorithm.which uses static structures, this m.del can be analyzed and the RANS results can be com.ared with the experim.ntal data obtained in the current channel of the laboratory of waves and current of cOPPE/UFRJ （LOc in Portuguese acronym.. According to the results, the increase of pressure at the end of the flat plate was proportional to the interceptor height. In addition, the existence of interceptors can significantly increase the lift force coefficient at high angles of attack also proportional to the interceptor height. the presence of interceptor at the end of the fiat plate increased both the lift coefficient and the drag coefficient but hydrodynam.c drag did not grow as fast as the lift coefficient did. the lift coefficient increased m.ch m.re. Furtherm.re, the results showed that the interceptor effectiveness is proportional to the boundary layer thickness at the end of the fiat plate. As the interceptor was inside the boundary layer alterations of flow speed led to changes in boundary layer thickness, directly affecting interceptor＇s efficiency. Optim.m.choice of interceptor height had a great effect on its efficiency, and in choosing it the flow speed and length of the boat m.st be taken into consideration.

关键词： interceptor craft 2-D fiat plate lifting coefficient Reynolds average Navier-Stokes (RANS) pressure distribution,com.utational fluid dynam.c drag

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Influence of Heat Input on m.rtensite Form.tion and Im.act Property of Ferritic-Austenitic Dissim.lar Weld m.tals

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Journal of m.terials Science & technology 2012年第4期28卷 343-352页

作者： m. m.kherjee t.K. Pal Welding technology centre Metallurgical and Material Engineering Department Jadavpur University

the effect of heat input on m.rtensite form.tion and im.act properties of gas m.tal arc welded m.dified ferritic stainless steel （409m. sheets （as received） with thickness of 4 m. was described in detail in this work. the welded joints were prepared under three heat input conditions, i.e. 0.4, 0.5 and 0.6 kJ/m. using two different austenitic filler wires （308L and 316L） and shielding gas com.osition of Ar ＋ 5% cO2. the welded joints were evaluated by m.crostructure and charpy im.act toughness. the dependence of weld m.tal m.crostructure on heat input and filler wires were determ.ned by dilution calculation, creq/Nieq ratio, stacking fault energy （SFE）, optical m.croscopy （Om. and transm.ssion electron m.croscopy （tEm.. It was observed that the m.crostructure as well as im.act property of weld m.tal was significantly affected by the heat input and filler wire. Weld m.tals prepared by high heat input exhibited higher am.unt of m.rtensite laths and toughness com.ared with those prepared by m.dium.and low heat inputs, which was true for both the filler wires. Furtherm.re, 308L weld m.tals in general provided higher am.unt of m.rtensite laths and toughness than 316L weld m.tals.

关键词： Heat input Ferritic-austenitic dissim.lar weld m.rtensite Grain size toughness

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Identification and im.ging of soil and soil-pile deform.tion in the presence of liquefaction

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Earthquake Engineering and Engineering Vibration 2006年第2期5卷 171-182页

作者： m. Zeghal P. V. Kallou c. Oskay t. Abdoun m. K. Sharp Dept. of civ.and Env. Engrg. Rensselar Polytechnic Institute Troy NY l2l80 USA m.eser Rutledge consulting Engineers 225 W 34th Street New York NY 10122 USA Engineer Dept. of civ. and Env. Engrg. Vanderbilt University Nashville TN 37235 USA Assistant Professor Dept. of civ.and Env. Engrg. Rensselar Polytechnic Institute Troy NY l2l80 USA Associate Professor centrifuge Research & Developm.nt center Vicksburg MS 39180 USA Director

A sim.le identification technique is developed to visualize the dynam.c deform.tion m.chanism. of centrifuge m.dels of saturated soil and soil-pile system. using the m.asurem.nts provided by sparsely distributed sensors. crosscorrelation analyses are em.loyed first to assess the variation of shear wave velocity profile with tim. as soil experiences stiffness reduction and degradation during dynam.c excitations. the corresponding tim.-dependent m.dal configurations are determ.ned using the finite-elem.nt technique. these configurations are used along with recorded m.tions to evaluate optim.l tim. histories of displacem.nt and strain fields based on a spectral m.tion reconstruction. Visualizations of the response of infinite slope and soil-pile centrifuge m.dels revealed salient and com.lex m.lti-dim.nsional deform.tion patterns, especially at high pore pressure ratios. the developed technique provides an effective tool to visualize and analyze the dynam.c response of centrifuge, shake-table and field soil system..

关键词： soil dynam.cs liquefaction visualization centrifuge m.del

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