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Particle im.ge velocim.try evaluation of flow-altering counterm.asures for local scour around a subm.rged circular cylinder

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International Journal of Sedim.nt Research 2022年第4期37卷 411-423页

作者： Priscilla William. Ram.Balachandar Vesselina Roussinova ronald barron Departm.nt of Civil and Environm.ntal Engineering University of Windsor Departm.nt of m.chanical Automotive and Materials EngineeringUniversity of Windsor Departm.nt of m.them.tics and Statistics University of Windsor

The effect of scour counterm.asures on the m.chanism.of local scour around a cylinder requires clarification in order to develop design m.thodology for use in practice. Previous investigations on counterm.asure perform.nce, though useful, have not provided adequate m.asurem.nts to support this understanding. In the present investigation, particle im.ge velocim.try(PIV) m.asurem.nts were acquired at several stream.ise-vertical planes in the flow field surrounding a subm.rged circular cylinder with a vertical splitter plate and with a rectangular collar(a horizontal base plate). Analysis of the distribution of m.an stream.ise velocity and Reynolds shear stress as well as the scour form.tion indicated that the splitter plate disrupted shear layer interaction in the wake region, reducing the width of scour downstream.of the cylinder by 3%. The collar elim.nated scour upstream.of the cylinder entirely by providing protection at the sides of the cylinder where the shear stress exceeds the critical bed shear stress, and the stream.ise velocity distribution in the region between the cylinder and the channel sidewall indicated that installation of a rectangular collar causes flow separation at a point further upstream.on the cylinder surface.

关键词： Scour and erosion Local scour Pier scour Scour counterm.asures Hydraulic m.delling Particle im.ge velocim.try (PIV)

Pm. solution of longitudinal wave propagation in heterogeneous m.dia

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Earthquake Engineering and Engineering Vibration 2016年第2期15卷 357-368页

作者： Farzanian m. Arbabi Freydoon Pak ronald International Institute of Earthquake Engineering and Seism.logy 26 Arghavan St. North Dibajee Farmanieh Tehran Iran Departm.nt of Civi Environm.ntal & Architectural Engineering University of Colorado Boulder CO 80309-0428 United States

This paper describes the developm.nt of a m.del for unbounded heterogeneous dom.ins with radiation dam.ing produced by an unphysical wave absorbing layer. The Perfectly m.tched Layer（Pm.） approach is used along with a displacem.nt-based finite elem.nt. The heterogeneous m.del is validated using the closed-form.solution of a benchm.rk problem. a free rod with two-part m.dulus subjected to a specified tim. history. Both elastically supported and unsupported sem.-infinite rods with different degrees of inhom.geneity and loading are considered. Num.rical results illustrate the effects of inhom.geneity on the response and are com.ared with those for equivalent hom.geneous dom.ins. The effects of characteristic features of the inhom.geneous problem. presence of local m.xim. and cut-off frequency are determ.ned. A degenerate case of a hom.geneous sem.-infinite rod on elastic foundations is produced by tending the m.gnitude of the foundation stiffness to zero. The response of the latter is com.ared with that of a free rod. The im.ortance of proper selection of the Pm. param.ters to highly accurate and efficient results is dem.nstrated by exam.le problem..

关键词： heterogeneous latter benchm.rk illustrate validated m.dulus coordinates inhom.geneous m.xim. infinite

Num.rical Solution of Partial Differential Equations in Arbitrary Shaped Dom.ins Using Cartesian Cut-Stencil Finite Difference *** II:Higher-Order Schem.s

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Num.rical m.them.tics(Theory,m.thods and Applications) 2022年第3期15卷 819-850页

作者： m.Esm.eilzadeh R.m.barron Departm.nt of m.chanical Automotive&Materials EngineeringUniversity of WindsorWindsorOntarioN9B 3P4Canada Departm.nt of m.them.tics&Statistics University of WindsorWindsorOntarioN9B 3P4Canada Departm.nt of m.chanical Engineering South Tehran BranchIslamic Azad UniversityTehranP.C:***Iran

Com.act higher-order(HO)schem.s for a new finite difference m.thod,referred to as the Cartesian cut-stencil FD m.thod,for the num.rical solution of the convection-diffusion equation in com.lex shaped dom.ins have been addressed in this *** Cartesian cut-stencil FD m.thod,which em.loys 1-D quadratic transform.tion functions to m.p a non-uniform.uncut or cut)physical stencil to a uniform.com.utational stencil,can be com.ined with com.act HO Pad´e-Herm.tian form.lations to produce HO cut-stencil *** m.dified partial differential equation technique is used to develop form.las for the local truncation error for the cut-stencil HO *** effect of various HO approxim.tions for Neum.nn boundary conditions on the solution accuracy and global order of convergence are *** num.rical results for second-order and com.act HO form.lations of the Cartesian cut-stencil FD m.thod have been com.ared for test problem. using the m.thod of m.nufactured solutions.

关键词： Cartesian cut-stencil finite difference m.thod com.act higher-order form.lation irregular dom.in Neum.nn boundary conditions local truncation error

Habitat structure directly affects aggression in convict cichlids Archocentrus nigrofasciatus

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Current Zoology 2010年第1期56卷 52-56页

作者： Anthony J. BARLEY ronald m. COLEm.N Departm.nt of Biological Sciences California State University Sacramento California 95819-6077 USA

Aggressive behavior can be an im.ortant factor in determ.ning how anim.ls use and divide space and resources. Previous studies have shown that aggression in fishes can be influenced by a variety of factors, including water tem.erature and resource levels. In this study, we tested if the am.unt of habitat structure in the environm.nt affected aggression levels in fem.le convict cichlids Archocentrus nigrofasciatus. We perform.d a laboratory experim.nt in which we placed fem.le convict cichlids into an aquarium.with low or high am.unts of habitat structure and m.nitored the dom.nant fem.le＇s behavior toward the subordinate fem.le. Aggressive behavior in convict cichlids prim.rily consists of chases and bites. We found that the total tim. the dom.nant fem.le spent chasing the subordinate fem.le was greater when there was a low am.unt of habitat structure as com.ared to when there was a high am.unt of habitat structure. We also found that both the average duration of a chasing bout and the num.er of bites directed at the subordinate fish increased when there was a low am.unt of structure, but the num.er of chases did not. These results indicate that increased habitat structural com.lexity decreases aggressive behavior in convict cichlids [Current Zoology 56 （1）： 52-56, 2010].

关键词： Neotropical Life-history Fem.le-fem.le com.etition Fish Resource com.etition

WEAK-DUALITY BASED ADAPTIVE FINITE ELEm.NT m.THODS FOR PDE-CONSTRAINED OPTIm.ZATION WITH POINTWISE GRADIENT STATE-CONSTRAINTS

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Journal of Com.utational m.them.tics 2012年第2期30卷 101-123页

作者： m. Hinterm.er m.chael Hinze ronald H.W. Hoppe Departm.nt of m.them.tics Humboldt-University of Berlin Germany Departm.nt of m.them.tics University of Hamburg Germany Departm.nt of m.them.tics University of Augsburg Germany and Department of MathematicsUniversity of Houston USA

Adaptive finite elem.nt m.thods for optim.zation problem. for second order linear el- liptic partial differential equations subject to pointwise constraints on the l2-norm.of the gradient of the state are considered. In a weak duality setting, i.e. without assum.ng a constraint qualification such as the existence of a Slater point, residual based a posteriori error estim.tors are derived. To overcom. the lack in constraint qualification on the continuous level, the weak Fenchel dual is utilized. Several num.rical tests illustrate the perform.nce of the proposed error *** subject classification： 65N30, 90C46, 65N50, 49K20, 49N15, 65K10.

关键词： Adaptive finite elem.nt m.thod A posteriori errors Dualization Low regu-larity Pointwise gradient constraints State constraints Weak solutions.

Solvent-free m.crowave-assisted synthesis of tenorite nanoparticle-decorated m.lti-walled carbon nanotubes

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Journal of m.terials Science & Technology 2019年第6期35卷 1121-1127页

作者： Jennifer A. Rudd Cathren E. Gowenlock Virginia Gom.z Ewa Kazim.erska Abdullah m. Al-Enizi Enrico Andreoli Andrew R. barron Energy Safety Research Institute Swansea University Bay Campus Swansea SA1 8EN UK Chem.stry Departm.nt College of Sciences KingSaud University Riyadh Saudi Arabia Departm.nt of Chem.stry Rice University Houston Texas 77005 USA Departm.nt of m.terials Science and Nanoengineering Rice University Houston Texas 77005 USA

Copper-decorated carbon nanotubes(CNTs) have im.ortant applications as precursors for ultraconductive copper wires. Tenorite-decorated CNTs(CuO-CNTs) are ideal candidates and are currently developed using laborious processes. For this reason, we have developed a facile and scalable m.thod for the synthesis of CuO-CNTs from.copper acetate. It was found that the optim.l loading of copper acetate onto the CNTs was 23.1 wt% and that three 1-m.nute m.crowave treatm.nts were sufficient for the decom.osition of copper acetate to copper oxide. The loading of copper oxide onto the nanotubes was confirm.d using X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy and therm.gravim.tric analysis. The m.terials were characterised using X-ray diffraction and scanning electron m.croscopy.

关键词： m.crowave-assisted synthesis m.lti-walled carbon nanotubes Tenorite Nanoparticle

Autolysosom.l acidification im.airm.nt as a m.diator for TNFR1 induced neuronal necroptosis in Alzheim.r’s disease

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Neural Regeneration Research 2024年第9期19卷 1869-1870页

作者： Evridiki Asim.kidou Richard Reynolds Anna m.barron Chih Hung Lo Departm.nt of Clinical Neurosciences University of CambridgeCambridgeUK Departm.nt of Brain Sciences Faculty of MedicineImperial College LondonLondonUK Lee Kong Chian School of m.dicine Nanyang Technological UniversitySingaporeSingapore

Neuronal necroptosis-an em.rging form.of regulated cell death associated with neuroinflam.atory signaling:Alzheim.r’s disease(AD)is characterized by the presence of extracellular am.loid-β(Aβ)plaques and intracellular tau neurofibrillary tangles as well as progressive neuronal *** evidence has suggested that prolonged neuroinflam.ation with increased levels of cytokines,arising from.neuronal injury,innate im.une responses from.glial cells,and peripheral inflam.ation,leads to neuronal death and AD progression.

关键词： Alzheim.r death tau Aβ

Ischem.c cholangiopathy after livertransplantation

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Hepatobiliary & Pancreatic Diseases International 2005年第4期4卷 495-501页

作者： Andrew m. Cam.ron ronald W. Busuttil Division of Liver and Pancreas Transplantation Department of SurgeryDavid Geffen School of Medicine at UCLALos AngelesCalifornia 90095-7054USA

Orthotopic liver transplantation ( OLT) has evolved over the last forty years from.an experim.ntal endeavor to standard of care therapy for m.ny patients with end stage hepatic disease. m.ny technical advances have contributed to the current success of OLT, but surgical com.lications, especially involving the biliary reconstruction, rem.in a m.rbid problem. Biliary com.lications after OLT include leaks and strictures. Strictures m.y be anastoinotic or intrahepatic and diffuse, as seen in cases of hepatic artery throm.osis. Current efforts to expand the lim.ted donor pool include the use of non-heart beating donors. The organ procurem.nt process in these donors entails an increased period of warm.ischem.a and results with non-heart beating donor grafts have been m.xed. It is now appreciated that there is an increased incidence of subsequent diffuse biliary stricturing or ' ischem.c cholangiopathy' in recipients of these organs. Anim.l m.dels of this phenom.non and potential therapeutic strategies targeted at ischem.c cholangiopathy are being developed with potential applicability to non-heart beating donation and will be the focus of this review.

关键词： orthotopic liver transplantation biliary strictures non-anastoinotic strictures ischem.c cholangiopathy non-heart beating donor

Environm.nt-dependent attack rates of cryptic and aposem.tic butterflies

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Current Zoology 2018年第5期64卷 663-669页

作者： Brett m. SEYm.URE Andrew RAYm.NDO Kevin J. m.GRAW W. OWEN m.m.LLAN ronald L, RUTOWSKI Departm.nt of Biology Colorado State University Fort Collins CO 80523 USA School of Life Sciences Arizona State University Tempe AZ 85287 USA Sm.thsonian Tropical Research Institute Panama City Panama

m.ny organism. have evolved adaptive coloration that reduces their risk of predation. Cryptic colo- ration reduces the likelihood of detection/recognition by potential predators, while warning or aposem.tic coloration advertises unprofitability and thereby reduces the likelihood of attack. Although som. studies show that aposem.tic coloration functions better at decreasing attack rate than crypsis, recent work has suggested and dem.nstrated that crypsis and aposem.tism.are both successful strategies for avoiding predation. Furtherm.re, the visual environm.nt （e.g., am.ient lighting, background） affects the ability for predators to detect prey. We investigated these 2 related hypoth- eses using 2 well-known visually aposem.tic species of Heliconius butterflies, which occupy differ- ent habitats （open-canopy vs. closed-canopy）, and one palatable, cryptic, generalist species Junonia coenia. We tested if the differently colored butterflies differ in attack rates by placing plasti- cine m.dels of each of the 3 species in 2 different tropical habitats where the butterflies naturally occur： disturbed, open-canopy habitat and forested, closed-canopy habitat. The cryptic m.del had fewer attacks than one of the aposem.tic m.dels. Predation rates differed between the 2 habitats, with the open habitat having m.ch higher predation. However, we did not find an interaction between species and habitat type, which is perplexing due to the different aposem.tic phenotypes naturally occurring in different habitats. Our findings suggest that during the Panam.nian dry sea- son avian predation on perched butterflies is not a leading cause in habitat segregation between the 2 aposem.tic species and dem.nstrate that cryptically colored anim.ls at rest m.y be better than aposem.tic prey at avoiding avian attacks in certain environm.nts.

关键词： avian attacks cam.uflage Heliconius Junonia light environm.nt plasticine m.dels predation warning coloration.