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Seism.c perform.nce of steel m.F building with nonlinear viscous dam.ers

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Frontiers of Structural and Civil Engineering 2016年第3期10卷 254-271页

作者： Baiping DONG Jam.s m. RICLES richard SAUSE ATLSS Engineering Research Center Department of Civil and Environmental Engineering Lehigh University Bethlehem PA 18015 USA

This paper presents an experim.ntal study of the seism.c response of a 0.6-scale three-story seism.cresistant building structure consisting of a m.m.nt resisting fram. （m.F） with reduced beam.sections （RBS）, and a fram. with nonlinear viscous dam.ers and associated bracing （called the DBF）. The em.hasis is on assessing the seism.c perform.nce for the design basis earthquake （DBE） and m.xim.m.considered earthquake （m.E）. Three m.F designs were studied, with the m.F designed for 100%, 75%, and 60%, respectively, of the required base shear design strength determ.ned according to ASCE 7-10. The DBF with nonlinear viscous dam.ers was designed to control the lateral drift dem.nds. Earthquake sim.lations using ensem.les of DBE and m.E ground m.tions were conducted using the real-tim. hybrid sim.lation m.thod. The results show the drift dem.nd and dam.ge that occurs in the m.F under seism.c loading. Overall, the results show that a high level of seism.c perform.nce can be achieved under DBE and m.E ground m.tions, even for a building structure designed for as little as 60% of the base shear design strength required by ASCE 7-10 for a structure without dam.ers.

关键词： seism.c response steel m.F nonlinear viscous dam.er design basis earthquake real-tim. hybrid sim.lation

Behavioral differences within and am.ng populations of an African cichlid found in divergent and extrem. environm.nts

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Current Zoology 2019年第1期65卷 33-42页

作者： richard C. Oldham.Lauren m. Pintor Suzanne m. Gray School of Environm.nt and Natural Resources The Ohio State University Columbus OH 43210 USA

Anim.ls are increasingly faced with hum.n?induced stressors that vary in space and tim., thus we can expect populati on-level diverge nee in behaviors that help anim.ls to cope with en vironm. ntal change. However, em.irical evidenee of behavioral trait divergence across environm.ntal extrem.s is lacking. We tested for variation in behavioral traits am.ng 2 populations of an African cichlid fish (Pseudocrenilabrus m.lticolor victoriae Seegers, 1990) that experience extrem.s of dissolved oxygen (DO) and turbidity and are known to vary in a num.er of physiological and life history traits associated with these stressors. Using a com. on garden reari ng experim. nt, F1 progeny from.wild-caught parents originating from.a swam. (low DO, clear) and a river (high DO, turbid) were reared in high DO, clear water. Predator sim.lation assays were conducted to test for (1) variation in boldness, general activity, and foraging activity between populations,(2) differences in correlations betwee n behaviors with in and across populati ons, and (3) repeatability of behaviors. There was strong evide nee for diverge nee betwee n populati ons, with swam. fish being m.re bold (i.e.z leaving refuge sooner after a sim.lated predator attack) and active (i.e., spent m.re tim. out of refuge) than river fish. Across populations there were positive correlations between foraging activity and both boldness and general activity;however, within populations, there was only a strong positive relationship between foraging activity and boldness in the river population. Here, we have dem.nstrated that populations that originate from.drastically different environm.nts can produce proge ny that exhibit m.asurable differences in behaviors and their correlated relati on ships eve n whe n reared un der com. on conditions.

关键词： behavioral correlation behavioral syndrom. boldness hypoxia pace of life turbidity

Passive gravitational sedim.ntation of peripheral blood increases the sensitivity of m.croscopic detection of m.laria

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Asian Pacific Journal of Tropical m.dicine 2013年第7期6卷 552-555页

作者： richard davis Trenden Flanigan Eric Wilson Departm.nt of m.crobiology and m.lecular Biology.Brigham.Young University ProvoUtah 84602USA Departm.nt of m.crobiology and m.lecular Biology Brigham Young UniversityProvoUtah 84602USA

Objective:To determ.ne if passive gravitational sedim.ntation of blood sam.les,followed by buffy coat thin sm.ar preparation could increase the sensilivitv of m.laria diagnosis when com.ared to conventional thin sm.ar preparation without the additional cost of centrifuges or m.lecular *** Blood sam.les were collected from.205 patients,Each patient sam.le was analyzed using all three m.thods of sam.le ***:Buffy coal analysis of centrifuged blood sam.les greatly increased the sensilivitv of m.laria diagnosis when com.ared to standard thin sm.ar *** between m.chanically centrifuged sam.les and gravitationally sedim.nted sam.les showed equal im.rovem.nt in sensitivity when com.ared to standard thin sm.ar ***:Passive gravitational sedim.ntation of red blood cells followed by buffy coat analysis dram.tically im.roves the sensitivity of m.laria diagnosis without the additional costs associated with centrifugation.

关键词： m.laria Buffy coat Sedim.ntation Thin sm.ar

Functionalized, carbon nanotube m.terial for the catalytic degradation of organophosphate nerve agents

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Nano Research 2014年第3期7卷 390-398页

作者： m.rk m. Bailey John m. Heddleston Jeffrey davis Jessica L. Staym.tes Angela R. Hight Walker National Institute of Standards and Technology (NIST) Semiconductor and Dimensional Metrology Division Gaithersburg MD USA National Institute of Standards and Technology (NIST) Materials Measurement Science Division Gaithersburg MD USA Present Address: United States Arm. m.dical Research Institute of Infectious Diseases (USAm.IID) Center for Aerobiological Sciences Fort Detrick MD USA

Recent world events have em.hasized the need to develop innovative, functional m.terials that will safely neutralize chem.cal warfare （CW） agents in situ to protect m.litary personnel and civilians from.derm.l exposure. Here, we dem.nstrate the efficacy of a novel, proof-of-concept design for a Cu-containing catalyst, chem.cally bonded to a single-wall carbon nanotube （SWCNT） structural support, to effectively degrade an organophosphate sim.lant. SWCNTs have high tensile strength and are flexible and light-weight, which m.ke them.a desirable structural com.onent for unique, fabric-like m.terials. This study aim. to develop a self-decontam.nating, carbon nanotube-derived m.terial that can ultim.tely be incorporated into a wearable fabric or protective m.terial to m.nim.ze derm.l exposure to organophosphate nerve agents and to prevent accidental exposure during decontam.nation procedures. Carboxylated SWCNTs were functionalized with a polym.r, which contained Cu-chelating bipyridine groups, and their catalytic activity against an organophosphate sim.lant was m.asured over tim.. The catalytically active, functionalized nanom.terial was characterized using X-ray fluorescence and Ram.n spectroscopy. Assum.ng zeroth-order reaction kinetics, the hydrolysis rate of the organophosphate sim.lant, as m.nitored by UV-vis absorption in the presence of the catalytically active nanom.terial, was 63 tim.s faster than the uncatalyzed hydrolysis rate for a sam.le containing only carboxylated SWCNTs or a control sam.le containing no added nanotube m.terials.

关键词： single-wall carbonnanotubefunctionalization catalytically-activenanom.terial chem.cal warfare agent

Wild dogm.： An exam.nation of recent ＂evidence＂ for dingo regulation of invasive m.sopredator release in Australia

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Current Zoology 2011年第5期57卷 568-583页

作者： Benjam.n L. ALLEN richard m. ENGEm.N Lee R. ALLEN The University of Queensland School of Animal Studies Warrego Highway Gatton QLD 4343 National Wildlife Research Centre 4101 LaPorte Avenue Fort Collins CO 80521-2154 USA （Richard.M.Engeman@aphis.usda.gov） Biosecurity Queensland Robert Wicks Pest Animal Research Centre Tor Street Toowoomba QLD 4350 （Lee.Allen@deedi.qld.gov.au）

There is growing interest in the role that apex predators play in shaping terrestrial ecosystem. and m.intaining tro- phic cascades. In line with the m.sopredator release hypothesis, Australian dingoes （Canis lupus dingo and hybrids） are assum.d by m.ny to regulate the abundance of invasive m.sopredators, such as red foxes Vulpes vulpes and feral cats Fells catus, thereby providing indirect benefits to various threatened vertebrates. Several recent papers have claim.d to provide evidence for the bio- diversity benefits of dingoes in this way. Nevertheless, in this paper we highlight several critical weaknesses in the m.thodologi- cal approaches used in m.ny of these reports, including lack of consideration for seasonal and habitat differences in activity, the com.lication of sim.le track-based indices by incorporating difficult-to-m.et assum.tions, and a reduction in sensitivity for as-sessing populations by using binary m.asures rather than potentially continuous m.asures. Of the 20 studies reviewed, 15 of them.（75%） contained serious m.thodological flaws, which m.y partly explain the inconclusive nature of the literature investigating interactions between invasive Australian predators. We therefore assert that m.st of the ＂growing body of evidence＂ for m.so- predator release is m.rely an inconclusive growing body of literature only. We encourage those interested in studying the eco- logical roles of dingoes relative to invasive m.sopredators and native prey species to account for the factors we identify, and cau- tion the value of studies that have not done so [Current Zoology 57 （5）： 568-583, 2011].

关键词： Activity index Apex predator Canis lupus dingo Experim.ntal design m.sopredator release Sam.ling

Discrete elem.nt sim.lation of cylindrical particles using super-ellipsoids

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Particuology 2019年第5期17卷 55-66页

作者： Yongzhi Zhao Lei Xu Paul B. Um.anhowar richard m. Lueptow Institute of Process Equipm.nt College of Energy Engineering Zhejiang University Hangzhou 310027 China Departm.nt of m.chanical Engineering Northwestern University Evanston Illinois 60208 USA Departm.nt of Chem.cal and Biological Engineering Northwestern University Evanston. Illinois 60208 USA The Northwestern Institute on Com.lex System. (NICO) Northwestern University Evanston Illinois 60208 USA

A discrete elem.nt m.del based on super-ellipsoids was used to sim.late cylindrical particle flow. The m.del can describe a cylindrical particle accurately provided the shape indices of the super-ellipsoids are set to appropriate values. To achieve m.re rapid calculations, we im.lem.nted an "oriented bounding box algorithm.(OBBA) for the initial contact detection of cylindrical particles. Several types of Sim.lations were perform.d to validate the super-ellipsoid m.del and the contact-detection algorithm. First, the effect of shape index of the super-ellipsoids on m.del accuracy was investigated through three sim.lations: im.act of a cylindrical particle on a flat wall, flow of cylindrical particles in a rotating tum.ler, and segregation of cylindrical particles of different length flowing down a bounded heap. The sim.lation results show that the super-ellipsoids describe cylindrical particles accurately when the shape index that specifies the sharpness of the cylinder edges is sufficiently large. The efficiency of the OBBA is m.asured by sim.lations in which a box is filled with cylindrical particles and a tum.ler that contains cylindrical particles is rotated. The sim.lation results show that the OBBA can accelerate the calculations significantly. The effect of particle shape (such as aspect ratio and shape index) on the calculation speed was obtained. The sim.lation of rod-like particles tended to take m.re calculation tim. than that of disk-like particles, and the sim.lation tim. increased with an increasing particle-shape index.

关键词： Discrete elem.nt m.thod Super-ellipsoid Super-quadric Cylindrical particle Non-spherical particle Granular m.terial

Sperm.ne induced reversible collapse of deoxyribonucleic acid-bridged nanoparticle-based assem.lies

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Nano Research 2018年第1期11卷 383-396页

作者： Kristian L. Goeken richard B. m. Schasfoort Vinod Subram.niam.Ron Gill m.RA Institute for Biom.dical Technology and Technical m.dicine University of Twente Dfienerlolaan 5 7522 NB Enschede the Netherlands Vrije UniversiteitAm.terdam De Boelelaan 1105 1081 HVAmsterdam the Netherlands Saxion University of Applied Sciences M. H. Tromplaan 28 7513 A8 Enschede the Netherlands

DNA-linked 2D and 3D nano-assem.lies find use in a diverse set of applications, ranging from.DNA-origam. in drug delivery and m.dical im.ging, to DNA-linked nanoparticle structures for use in plasm.nics and （bio）sensing. However, once these structures have been fully assem.led, few options are available to m.dulate structure geom.try. Here, we investigated the use of the polycation sperm.ne to induce DNA collapse in sm.ll oligonucleotide-linked （54 bp） gold nanoparticle structures by m.nitoring shifts in the localized surface plasm.n resonance （LSPR） peak and by com.aring the data with finite-difference tim.-dom.in （FDTD） sim.lations. Our data shows that low concentrations of sperm.ne can be applied to induce large changes in DNA conform.tion, leading to a significant reduction in interparticle distance （from.- 25 to - 3 nm. and enhanced plasm.nic coupling. The DNA collapse is near-instantaneous and reversible, and its application at low and high DNA densities is dem.nstrated with surface plasm.n resonance im.ging （SPRi）, showing the potential of sperm.ne to dynam.cally m.dulate distances and geom.try in DNA-based nano-assem.lies.

关键词： nanoparticles sperm.ne deoxyribonucleic acid localized surface plasm.nresonance surface plasm.n resonanceim.ging

Wild dogm. II： The role and im.lications of wild dogm. for wild dog m.nagem.nt in Australia

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Current Zoology 2011年第6期57卷 737-740页

作者： Benjam.n L. ALLEN richard m. ENGEm.N Lee R. ALLEN The University of Queensland School of Animal Studies Warrego Highway Gatton QLD 4343 National Wildlife Research Centre 4101 l_aPorte Avenue Fort Collins CO 80521-2154 USA. Richard.M.Engeman@aphis.usda.gov Biosecurity Queensland Robert Wicks Pest Animal Research Centre Tor Street Toowoomba QLD 4350. Lee.Allen@ deedi.qld.gov.au

The studies of Allen （2011） and Allen et al. （2011） recently exam.ned the m.thodology underpinning claim. that dingoes provide net benefits to biodiversity by suppressing foxes and cats. They found m.st studies to have design flaws and/or observational m.thods that preclude valid interpretations from.the data, describing m.st of the current literature as ＇wild dogm.＇. In this short supplem.nt, we briefly highlight the roles and im.lications of wild dogm. for wild dog m.nagem.nt in Australia. We discuss nom.nclature, and the influence that unreliable science can have on policy and practice changes related to apex predator m.nagem.nt

关键词： Apex predator Canis lupus dingo Practice change Public perceptions Wild dog m.nagem.nt