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CreatorTitleDescriptionSubjectDate
276 DeTar, CarletonContinuum limit of lattice QCD with staggered quarks in the quenched approximation: a critical role for the chiral extrapolationWe calculate the light quark spectrum of lattice QCD in the quenched approximation using staggered quarks. We take the light quark mass, infinite volume, continuum limit. With nonlinear chiral extrapolations, we find that the nucleon to p mass ratio is mN/mp =­ 1.254 + 0.018 + 0.028, where the err...Staggered quarks; Chiral extrapolations1998-10
277 Goller, FranzContributions of expiratory muscles to song production in zebra finchesBirdsong production requires coordinated activity of syringeal and respiratory muscles, Phonation occurs during the expiratory phase of the respiratory cycle, and expiratory muscles generate the pressure head for sound production.Phonation; Syringeal muscles; Air sac pressure1999
278 Lupton, John MarkControl of mobility in molecular organic semiconductors by dendrimer generationConjugated dendrimers are of interest as novel materials for light-emitting diodes. They consist of a luminescent chromophore at the core with highly branched conjugated dendron sidegroups. In these materials, light emission occurs from the core and is independent of generation. The dendron branchin...Dendrimer generation; Dendron branching; Charge transport; Mobility2001-03
279 Minteer, Shelley D.Controlled placement of enzymes on carbon nanotubes using comb-branched DNAImmobilization is not only useful for preserving enzyme activity, but also to adhere an enzyme to a surface, such as an electrode, so that the enzyme does not leach into solution during testing. Current immobilization approaches do not readily allow for adjustments to the distance between the enzyme...2014-01-01
280 Olivera, Baldomero M.; Gray, William RobertContryphan is a D-tryptophan-containing Conus peptideIn this report, we document for the first time the occurrence of D-tryptophan in a normally translated polypeptide, contryphan. The peptide, isolated from the venom of the fish-hunting marine snail Conus radiatus, produces the "stiff-tail" syndrome in mice.Conotoxins; Contryphan; D-tryptophan; Conus peptides; Conus radiatus; Stiff-tail syndrome1996
281 Olivera, Baldomero M.; Gray, William Robert; Yoshikami, DojuConus geographus toxins that discriminate between neuronal and muscle sodium channelsWe describe the properties of a family of 22-amino acid peptides, the μ-conotoxins, which are useful probes for investigating voltage-dependent sodium channels of excitable tissues. The μ-conotoxins are present in the venom of the piscivorous marine snail, Conus geographus L. We have purified even...Conus geographus; Venom; Conotoxins; Sodium channels; Neurotoxins1985
282 Olivera, Baldomero M.; McIntosh, J. MichaelConus peptides as tools for the neuroscientistRecombinant DNA technology has had a powerful impact on understanding receptors and ion channels, the key components in the nervous system that are involved in intercellular communication. Cloning genes encoding these proteins has revealed that for every receptor and ion channel type, multiple molec...Conus peptides; Conotoxins1993
283 Olivera, Baldomero M.Conus peptides: biodiversity-based discovery and exogenomicsThe venoms of the ~700 species of predatory cone snails (genus Conus) are being systematically characterized. Each Conus species contains 100-200 small, highly structured venom peptides (colloquially known as conotoxins), which are synthesized and secreted in a venom duct (for overviews, see Refs. ...Conotoxins; Conus peptides; Exogenomics2006
284 Olivera, Baldomero M.Conus peptides: phylogenetic range of biological activityThe major function of the venoms of the predatory marine snails belonging to the genus Conus is to paralyze prey. Thus, the venom of each Conus species acts on receptors and ion channels of the prey; previous studies suggested much less activity on homologous receptor targets in more distant taxa....Conus peptides; Conopeptides; Conotoxins1992
285 Olivera, Baldomero M.Conus venom peptides, receptor and ion channel targets, and drug design: 50 million years of neuropharmacologyThe predatory cone snails (Conus) are among the most successful living marine animals (~500 living species). Each Conus species is a specialist in neuropharmacology, and uses venom to capture prey, to escape from and defend against predators and possibly to deter competitors. An individual cone...Conotoxins1997
286 Miller, Joel StevenConvenient synthesis of C5(CD3)5H. synthesis and characterisation of Fe{n5-C5(CD3)5}2The large scale synthesis of deuterio(pentamethylcyclopentadiene), C5(CD3)5H ([2H30]Cp*H), and subsequent synthesis of [2H30][Fe(n|-Cp*)2] is described, together with i.r., Raman, and solid state 2H n.m.r. spectroscopic characterisation.Organometallic; Catalytic1988
287 Golden, Kenneth M.Convexity and exponent inequalities for conduction near percolationThe bulk conductivity o*(p) of the bond lattice in Zd with a fraction p of conducting bonds is analyzed. Assuming a hierarchical node-link-blob (NLB) model of the conducting backbone, it is shown that o*(p) (for this model) is convex in p near the percolation threshold pc, and that its critical expo...Lattice; Conductivity; Model1990
288 Golden, Kenneth M.Convexity in random resistor networksThe bulk conductivity o*(p) of the bond lattice in Zd is considered, where the conductivity of the bonds is either 1 with probability p or e > 0 with probability 1 - p. Rigorous and non-rigorous results demonstrating convexity of o*(p) near the percolation threshold pc are presented.Conductivity; Bond lattice; Critical exponent t1989
289 Vardeny, Zeev ValentineCooperative and stimulated emission in poly(p-phenylene-vinylene) thin films and solutionsWe discuss cooperative and stimulated emissions and separate their respective contributions to the emission spectral narrowing in thin films and solutions of poly(p-phenylene-vinylene) derivatives. Whereas cooperative radiation is favored in films with poor optical confinement, directional stimula...pi-conjugated polymers; PPV; Spectral narrowing1998-04
290 Vardeny, Zeev Valentine; Raikh, Mikhail E.Cooperative emission from a disordered system: a classical modelThe effect of disorder on the collective emission from a system of classical oscillators is studied theoretically. Three types of disorder are considered: random orientation of dipole moments, finite spread in frequencies of the individual oscillators (diagonal disorder), and dipole-dipole interacti...Cooperative emission; Disordered system; Dipole-dipole interaction; Oscillators1997
291 Vardeny, Zeev ValentineCooperative emission in ∏-conjugated polymer thin filmsPicosecond dynamics of exciton emission and absorption have been studied in neat thin films of a variety of poly (phenylene vinylene) derivatives. We found that the stimulated emission band of 120 nm width and ~1 ns duration, which is observed at low exciton density n, collapses at n > 1017 cm-3 int...Pi-conjugated polymers; Poly (phenylene vinylene) derivatives; PPV derivatives; Cooperative emission1997-01
292 Goller, FranzCoordination and synergism between visual and vocal display in the brown-headed cowbirdsSexually selected acoustic signaling is accompanied by visual displays in many birds. The motor integration of visual and vocal displays has not been extensively studied. Brown-headed cowbirds (Molothrus ater) "puff up" prior to song, move their wings during the song and conclude with a bow. The ...Acoustic signaling; Wing display; Synergistic interaction2003
293 Sekercioglu, CaganCorrelates of elevational specialisation in Southeast Asian tropical birdsThe understanding of elevational selectivity in extremely rich tropical biotas is critical to the study of accelerating human-mediated environmental changes (e.g., deforestation and global climate warming). This paper explores the characteristics of Southeast Asian birds that are altitudinal special...2012-01-01
294 Gondolo, PaoloCosmic ray positron excess and neutralino dark matterUsing a new instrument, the HEAT Collaboration has confirmed the excess of cosmic ray positrons that they first detected in 1994. We explore the possibility that this excess is due to the annihilation of neutralino dark matter in the galactic halo. We confirm that neutralino annihilation can produ...Neutralinos; Supersymmetric models; Positron flux; Annihilations2002-02
295 Kieda, David B.; Gaisser, Thomas K.; Sokolsky, PierreCosmic-ray composition around 10^18 eVWe use the depth of maximum distribution as measured by the stereo Fly's Eye detector to study the chemical composition of the primary cosmic radiation between 3x 1017 eV and 1019 eV. The analysis depends on the use of simulations to study the response of the detector as well as sensitivity to assum...Fly's Eye; Cosmic ray composition; Cosmic ray nuclei; Chemical composition1993-03
296 Sokolsky, PierreCosmic-ray composition around 10^18 eVWe use the depth of maximum distribution as measured by the stereo Fly's Eye detector to study the chemical composition of the primary cosmic radiation between 3 x 10^17 eV and 10^19 eV. The analysis depends on the use of simulations to study the response of the detector as well as sensitivity to as...Energy spectrum; Extensive air showers; Inelasticity; Hadronic interactions1993-03
297 Mishchenko, EugeneCoulomb drag by small momentum transfer between quantum wiresWe demonstrate that in a wide range of temperatures Coulomb drag between two weakly coupled quantum wires is dominated by processes with a small interwire momentum transfer. Such processes, not accounted for in the conventional Luttinger liquid theory, cause drag only because the electron dispersion...Coulomb drag; Quantum wires; Luttinger liquid2003-09
298 Carrier, David R.Coupled evolution of breathing and locomotion as a game of leapfrogBecause the increase in metabolic rate related to locomotor activity places demands on the cardiorespiratory apparatus, it is not surprising that the evolution of breathing and of locomotion are coupled. As the respiratory faculty becomes more refined, increasingly aerobic life strategies can be exp...Evolution; Coupled evolution; Breathing; Locomotion; Cardiorespiratory apparatus2006
299 Capecchi, Mario R.Creating mice with targeted disruptions in protooncogenes and homeobox genes, NIH Director's Lecture given May 21, 1992This is an audio transcript of a 1 hour, 2 minutes and 12 seconds lecture given at the National Institutes of Health by Mario Capecchi on 1992/05/21. Beginning with a short summary of the mechanics of gene transfer and the ability to create germline chimera with mutations that become hereditary wit...Transgenic mice; Gene targeting; Genetic engineering; Molecular genetics; Mutagenesis; Homeobox genes; Histology - Pathological; Gene expression; Gene regulation; Genotype; Phenotype1992
300 DeTar, CarletonCritical behavior at the chiral phase transitionIt is generally expected that two-flavor QCD undergoes a high temperature chiral symmetry restoring phase transition at zero quark mass, with O(4) critical behavior[1]. Verifying this expectation is important for understanding the phenomenology of the transition and for facilitating an extrapolation...Phase transitions; Staggered fermions1998-04
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