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CreatorTitleDescriptionSubjectDate
476 Lupton, John MarkEnergetic disorder limits energy transfer in semiconductor nanocrystal-DNA-dye conjugatesWe demonstrate the influence of spectral linewidths of individual donor-acceptor couples on energy transfer efficiency in semiconductor nanocrystal-DNA-organic dye conjugates. Temperature-dependent single molecule and ensemble spectroscopy data are analyzed using the Förster theory within the mac...2009
477 Armentrout, Peter B.Energetics and dynamics in the reaction of Si+ with SiF4. Thermochemistry of SiFx and SiFx+ (x=1,2,3)The title reaction is studied using guided ion beam mass spectrometry. Absolute reaction cross sections are measured as a function of kinetic energy from thermal to 40 eV, and three endothermic product channels are observed. The dominant SiF+ + SiF3 channel is only slightly endothermic, while the ...Silicon fluoride; Ion-molecule reactions; Kinetic energy; Threshold behavior; Endothermic reactions1988
478 Symko, Orest GeorgeEnergy conversion using thermoacoustic devicesThermoacoustic engines offer the possibility for simple and efficient energy convmiondevices. They can be prime movers where heat produces sound or heat pumps and refrigerators where sound pump heat. An important element in such engines is the secondary thermodynamic medium, the stack which provides...Thermoacoustic devices; Thermoacoustics1999
479 Armentrout, Peter B.Energy dependence, kinetic isotope effects, and thermochemistry of the nearly thermoneutral reactions of N+(3P) + H2(HD, D2) → NH+(ND+) + H(D)The reactions of N + (3P) ions with H2 , HD, D2 are examined using guided ion beam tandem mass spectroscopy. Absolute reaction cross sections are measured from near thermal energies to 30 eV relative energy. The low energy cross section behavior is analyzed using empirical threshold models and ph...Thermoneutral reactions; Ion-molecule reactions; Translational energy; Bond energy; Threshold behavior; Phase space theory1987
480 Sokolsky, PierreEnergy estimation of UHE cosmic rays using the atmospheric fluorescence techniqueWe use the CORSIKA air shower simulation program to review the method for assigning energies to ultra-high energy (UHE) cosmic rays viewed with the air fluorescence technique. This technique uses the atmosphere as a calorimeter, and we determine the corrections that must be made to the calorimetric ...Fluorescence; Energy estimation; Ultra-high energy cosmic rays2000-08
481 Rogachev, AndreyEnhancing superconductivity: magnetic impurities and their quenching by magnetic fieldsMagnetic fields and magnetic impurities are each known to suppress superconductivity. However, as the field quenches (i.e. polarizes) the impurities, rich consequences, including field-enhanced superconductivity, can emerge when both effects are present. For the case of superconducting wires and th...Thermal phase slippage; Coulomb blockade2006-09-01
482 Ehleringer, James R.ENSO effects on primary productivity in Southern Atacama desertIn the winter-rain southern Atacama Desert of the Coquimbo Region of Chile, El Niño - Southern Oscillation (ENSO) events modulate primary productivity. In this region, there are important changes in water availability between La Niña (dry) and El Niño (rainy) years. Using interannual comparison...El Niño; Atacama Desert; Terrestrial ecosystems; Plant productivity2006
483 Poulter, Charles DaleEnzymes encoded by the farnesyl diphosphate synthase gene family in the big sagebrush Artemisia tridentata ssp. spiciformisFarnesyl diphosphate synthase catalyzes the sequential head-to-tail condensation of two molecules of isopentenyl diphosphate with dimethylallyl diphosphate. In plants the presence of farnesyl diphosphate synthase isozymes offers the possibility of differential regulation. Three full-length cDNAs enc...Amino Acid Sequence; Base Sequence; Molecular Sequence Data2003-08-22
484 DeTar, CarletonEquation of state and QCD transition at finite temperatureWe calculate the equation of state in 2 + 1 flavor QCD at finite temperature with physical strange quark mass and almost physical light quark masses using lattices with temporal extent Nr = 8. Calculations have been performed with two different improved staggered fermion actions, the asqtad and p4 a...Deconfinement; Chiral symmetry; Staggered fermions; Phase transitions; Polyakov loop2009-07
485 DeTar, CarletonEquation of state for two flavor QCD at Nt=6We calculate the two flavor equation of state for QCD on lattices with lattice spacing a=(6T)21 and find that cutoff effects are substantially reduced compared to an earlier study using a=(4T)21. However, it is likely that significant cutoff effects remain. We fit the lattice data to expected forms ...Phase transitions; Quark-gluon plasma; Dynamical quarks1997-06
486 DeTar, CarletonEquation of state for two flavor QCD at Nt=6We calculate the two flavor equation of state for QCD on lattices with lattice spacing a=(6T)21 and find that cutoff effects are substantially reduced compared to an earlier study using a=(4T)21. However, it is likely that significant cutoff effects remain. We fit the lattice data to expected forms ...Phase transitions; Quark-gluon plasma; Chiral symmetry1997-06
487 Mishchenko, EugeneEquilibrium currents in chiral systems with nonzero Chern numberWe describe a simple quantum-mechanical approach to calculating equilibrium particle current along the edge of a system with nontrivial band spectrum topology. The approach does not require any a priori knowledge of the band topology and, as a matter of fact, treats topological and nontopological co...2014-01-01
488 Capecchi, Mario R.Establishment of mammalian cell lines containing multiple nonsense mutations and functional suppressor tRNA genes.We describe the generation of mammalian cell lines carrying amber suppressor genes. Nonsense mutants in the herpes simplex virus thymidine kinase (HSV tk) gene, the Escherichia coli xanthine-guanine phosphoribosyl transferase (Eco-gpt) gene and the aminoglycoside 3' phosphotransferase gene of the Tn...Cercopithecus aethiops; Escherichia coli; Xenopus1982-11-30
489 Bohs, Lynn A.Ethnobotany of the genus Cyphomandra (Solanaceae)Plants of the genus Cyphomandra (Solanaceae) have long been utilized for their edible fruits in their native Latin America. The best-known species is the domesticated tree tomato or tamarillo, Cyphomandra betacea. This species, popular as a raw or cooked fruit, is widely cultivated in Andean South ...Cyphomandra; Cyphomandra betacea; Alkaloids1989
490 Ehleringer, James R.Evaluación de la capacidad estacional de utilizar eventos de preciptación en tres especies de arbustos nativos de Chile con distintos sistemas radicularesSe evaluó la capacidad estacional de utilizar un evento de precipitación en tres especies arbustivas con diferentes sistemas radiculares (dimórficos: Balbisia peduncularis, Senna cumingii; profundo: Haplopappus parvifolius) en la Quebrada El Romeral, norte-centro de Chile. El sitio posee un clima...Fuentes de agua; Proporción de isótopos estables; Sistema radicular; Desertificación; Zonas áridas; Chile; Water sources; Stable isotopes ratio; Root system; Arid zone; Balbisia peduncularis; Senna cummingii; Haplopappus parvifolius2002
491 Sperry, John S.Evaluation of Murray's law in Psilotum nudum (Psilotaceae), an analogue of ancestral vascular plantsPrevious work has shown that the xylem of seed plants follows Murray's law when conduits do not provide structural support to the plant. Here, compliance with Murray's law was tested in the stem photosynthesizer Psilotum nudum, a seedless vascular plant. Psilotum nudum was chosen because the central...Conduit furcation number; hydraulic architecture; Murray's law2005
492 Gondolo, PaoloEvidence for "sterile neutrino" dark matter?I show that it may be possible to explain the present evidence for a gamma-ray emission from the galactic halo as due to halo WIMP annihilations. Not only the intensity and spatial pattern of the halo emission can be matched but also the relic density of the candidate WIMP can be in the cosmologica...Sterile neutrino; WIMP; Weakly interacting massive particles; Annihilations; Z boson; Higgs sector1998
493 Sokolsky, PierreEvidence for 10^18-eV neutral particles from the direction of Cygnus X-3Analysis of the cumulative Fly's Eye data reveals an excess of air showers from the direction of Cygnus X-3 at energies above 0.5 x 10^18 eV. No point source has previously been identified at such high energies. The probability of this excess arising as a chance clustering of isotropic cosmic rays i...Cygnus X-3; Extensive air showers; Neutral particles1989-01
494 Seger, JonEvidence for a cryptic species complex in the ant parasitoid Apocephalus paraponerae (Diptera: Phoridae)Cryptic species complexes occur in many taxa, in particular in the insect order Diptera. Here we describe a possible new cryptic species complex in the family Phoridae. Three lines of evidence suggest that Apocephalus paraponerae, an ant parasitoid, is actually a complex of at least four genetically...Host; Sequence; Populations2001
495 Sokolsky, Pierre; Cassiday, George L.Evidence for a high-energy cosmic-ray spectrum cutoffWe report a measurement of the ultrahigh-energy cosmic-ray spectrum using an atmospheric fluorescence technique for extensive-air-shower detection. The differential spectrum between 0.1 and 10 EeV (1 EeV = 10^18 eV) is well fitted by a power law with slope 2.94 ±0.02. Above 10 EeV evidence is prese...Energy spectrum; Extensive air showers; Spectral cutoff1985-04
496 Vardeny, Zeev Valentine; Raikh, Mikhail E.Evidence for braggoriton excitations in opal photonic crystals infiltrated with highly polarizable dyesWe studied angle-dependent reflectivity spectra of opal photonic crystals infiltrated with cyanine dye aggregates, which are highly polarizable media with very large Rabi frequency. We show that, at resonance condition between the exciton-polariton of the dye aggregate and the Bragg gap, the Bragg s...Braggoriton excitations; Opal photonic crystals; Cyanine dye aggregates; Bragg; Photonic band-gap; PBG; Polarizable dyes2002
497 Kieda, David B.Evidence for changing of cosmic ray composition between 10(17) and 10(18) eV from multicomponent measurementsThe average mass composition of cosmic rays with primary energies between 1017 and 1018 eV has been studied using a hybrid detector consisting of the High Resolution Fly's Eye (HiRes) prototype and the MIA muon array. Measurements have been made of the change in the depth of shower maximum and the ...Cosmic rays; Particle energy; Muon array2000
498 Sokolsky, PierreEvidence for changing of cosmic ray composition between 10^17 and 10^18 eV from multicomponent measurementsThe average mass composition of cosmic rays with primary energies between 1017 and 1018 eV has been studied using a hybrid detector consisting of the High Resolution Fly's Eye (HiRes) prototype and the MIA muon array. Measurements have been made of the change in the depth of shower maximum and the...Extensive air showers; Fluorescence; Energy spectrum; Muon density; Cherenkov light2000-05
499 Sokolsky, PierreEvidence for correlated changes in the spectrum and composition of cosmic rays at extremely high energiesThe Utah Fly's Eye detector has revealed a change in the cosmic ray composition which is correlated with structure in the all-particle energy spectrum. The data can be fitted by a simple model of a steep power law spectrum of heavy nuclei which is overtaken at high energies by a flatter spectrum of ...Energy spectrum; Extensive air showers1993-11
500 Kieda, David B.; Gaisser, Thomas K.; Sokolsky, PierreEvidence for correlated changes in the spectrum and composition of cosmic rays at extremely high energiesThe Utah Fly's Eye detector has revealed a change in the cosmic ray composition which is correlated with structure in the all-particle energy spectrum. The data can be fitted by a simple model of a steep power law spectrum of heavy nuclei which is overtaken at high energies by a flatter spectrum o...Ultrahigh energy cosmic rays; Fly's Eye; Cosmic ray composition; Cosmic ray spectrum1993-11
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