UScholar Works
 
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226 - 250 of 1,938
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CreatorTitleDescriptionSubjectDate
226 Linton, Matthew J.Magnitude and mechanisms of disequilibrium between predawn plant and soil water potentialsPredawn plant water potential (Uw, measured with leaf psychrometers) and surrogate measurements made with the pressure chamber (termed Upc here) are used to infer comparative ecological performance, based on the expectation that these plant potentials reflect the wettest soil Uw accessed by roots. T...Roots; Transpiration; Solutes2003
227 Mattis, Daniel C.Theory of paramagnetic impurities in semiconductorsIn this paper, a model of a paramagnetic impurity in a semiconductor (or of an F' center in an alkali halide) is proposed. It is an exactly soluble form of the quantum-mechanical 3-body problem. Specifically, we deal with 2 interacting particles in any number of dimensions in an attractive external ...Paramagnetic impurities; Eigenstates1966
228 Mishchenko, EugeneFrequency dependence of the photonic noise spectrum in an absorbing or amplifying diffusive mediumA theory is presented for the frequency dependence of the power spectrum of photon current fluctuations originating from a disordered medium. Both the cases of an absorbing medium ("grey body") and of an amplifying medium ("random laser") are considered in a waveguide geometry. The semiclassical ap...Random laser; Noise power spectrum; Frequency dependence; Waveguide geometry2001-01
229 Adler, Frederick R.Alternating host cell tropism shapes the persistence, evolution and coexistence of Epstein-Barr virus infections in humanEpstein-Barr virus (EBV) infects and can persist in a majority of people worldwide. Within an infected host, EBV targets two major cell types, B cells and epithelial cells, and viruses emerging from one cell type preferentially infect the other. We use mathematical models to understand why EBV infec...2011
230 Gerton, JordanSinglet s-wave scattering lengths of 6Li and 7LiPhotoassociation of ultracold lithium atoms into bound vibrational levels of the A 1Σu+ excited state is used to probe the X1Σg+ ground-state interaction potential of 6Li2 and 7Li2 . It had been predicted that the s-wave photoassociation signal strength would pass through a minimum as a function...1996-06
231 Gerton, JordanTip-enhanced fluorescence microscopy at 10 nanometer resolutionWe demonstrate unambiguously that the field enhancement near the apex of a laser-illuminated silicon tip decays according to a power law that is moderated by a single parameter characterizing the tip sharpness. Oscillating the probe in intermittent contact with a semiconductor nanocrystal strongly...2004-10
232 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
233 Lupton, John MarkLinewidth-limited energy transfer in single conjugated polymer moleculesUsing low temperature single molecule spectroscopy on rigid-rod conjugated polymers we are able to identify homogeneously broadened, strongly polarized emission from individual chromophore units on a single chain. Gated fluorescence spectroscopy allows real time imaging of intramolecular energy tran...Linewidth-limited; Energy transfer; Rigid-rod; Single molecule spectroscopy; Gated fluorescence spectroscopy; Chromophores; Intramolecular energy transfer; Spectral linewidth2003-12
234 Goller, FranzRespiratory motor correlates of song plasticity in young adult zebra finchesYoung adult zebra finches (Taeniopygia guttata, 90150 phd) sing a stereotyped song, but can show rapid changes in song structure if sensory feedback is disrupted. The vocal motor correlates accompanying induced song plasticity have not yet been examined. To investigate motor changes underlying song ...Pattern; Muting; Sound2002
235 Kieda, David B.Overview of the ANITA projectThe ANITA project is designed to investigate ultra-high energy (>1017 eV) cosmic ray interactions throughout the universe by detecting the neutrinos created in those interactions. These high energy neutrinos are detectable through their interactions within the Antarctic ice sheet, which ANITA will u...ANITA; Antarctic Impulsive Transient Antenna; High energy neutrinos; Antarctica; Balloon2003
236 Miller, Joel StevenSynthesis, structural, and magnetic characterization of substituted benzoimidazole-l-yl N,N'-dioxidesThe crystal structures, EPR spectra and magnetic properties of the novel halogen- and cyano-substituted nitronyl nitroxide radicals 2-(2,6-dichlorophenyl)benzimidazolyl N,N'-dioxide, 6, 2-(2,6-difluorophenyl)benzimidazolyl N,N'- dioxide, 7, 2-(2-chloro-6-fluorophenyl)benzimidazolyl N,N'-dioxide, 8,...Organic; Ferromagnetic; Coupling2004
237 Miller, Joel StevenPhotoelectron spectra of transition-metal carbonyl complexes: comparison with the spectra of adsorbed COThe uv and x-ray photoelectron spectra of carbon monoxide and transition-metal (TM) carbonyl complexes have been studied. The systematic changes in these spectra were recorded as the number of metal atoms in the complexes was increased and as the bonding configuration of the CO changed. The observat...TM carbonyl complexes; electron binding energies; metal atoms1978
238 Capecchi, Mario R.Hox genes and mammalian developmentWe have examined the interactions of Hox genes in forming a cervical vertebrae, hindbrain, and limbs. In each case, it is apparent that individual Hox genes are performing individual functions but that more profound roles are apparent when they act in combination with others Hox genes. The observed ...Drosophila; Gene Expression Regulation, Developmental; Homozygote1997
239 Gondolo, PaoloDark matter axions revisitedWe study for what specific values of the theoretical parameters the axion can form the totality of cold dark matter. We examine the allowed axion parameter region in the light of recent data collected by the WMAP5 mission plus baryon acoustic oscillations and supernovae, and assume an inflationary...WMAP5 mission; PQ symmetry; Anharmonicity; Misalignment angle2009-08
240 Armentrout, Peter B.Infrared multiple photon dissociation spectroscopy of cationized cysteine: effects of metal cation size on gas-phase conformationAbstract The gas-phase structures of cationized cysteine (Cys) including complexes with Li+, Na+, K+, Rb+, and Cs+, as well as protonated Cys, are examined by infrared multiple photon dissociation (IRMPD) action spectroscopy utilizing light generated by a free electron laser, in conjunction with q...2010
241 Morse, Michael DavidResonant two-photon ionization spectroscopy of BNBTriatomic BNB has been produced by laser ablation of a boron nitride rod in a supersonic expansion of helium carrier gas and has been investigated using resonant two-photon ionization spectroscopy in the visible region. The B? 2IIg?X? 2?u + band system has been recorded near 514 nm and is dominated ...2006
242 Symko, Orest GeorgeMagnetic anisotropy of Zn-Cr alloys at very low temperaturesThe temperature dependent magnetization of Zn-Cr single crystals was measured from 2K down to 10 mK using a SQUID magnetometer. A large anisotropy is observed for the magnetization along the parallel and perpendicular axes of the crystal. For low concentrations impurity-impurity reactions do not do...Magnetic anisotropy; Zn-Cr alloys; Temperature dependent magnetization1978
243 Olivera, Baldomero M.; Hillyard, David R.; Gray, William Robertĸ-Conotoxin PVIIA is a peptide inhibiting the Shaker K+ channelĸ-Conotoxin PVIIA (k-PVIIA), a 27-amino acid toxin from Conus purpurascens venom that inhibits the Shaker potassium channel, was chemically synthesized in a biologically active form. The disulfide connectivity of the peptide was determined. ĸ-Conotoxin PVIIA has the following structure.Conotoxins; k-Conotoxin PVIIA; Conus purpurascens1998
244 Frederick, Jeanne M.; Baehr, WolfgangReceptor for advanced glycation end products and age-related macular degeneration.Advanced glycation end products (AGE) exacerbate disease progression through two general mechanisms: modifying molecules and forming nondegradable aggregates, thus impairing normal cellular/tissue functions, and altering cellular function directly through receptor-mediated activation. In the present...Optic Atrophies, Hereditary; Apoptosis; Pigment Epithelium of Eye2004
245 Vardeny, Zeev ValentineOptically-detected magnetic-resonance study of triplet state dynamics in C70We present studies of fluorescence, phosphorescence, photoinduced absorption, and their respective optically detected magnetic resonance of C70 molecules dispersed in polystyrene glasses. Two distinct triplet excitons are identified with principle zero-field splitting parameters (D≈0.0089 and 0.0...Ttriplet state dynamics; C70; Polystyrene glasses1996-03
246 Gondolo, PaoloCan WIMP spin dependent couplings explain DAMA data, in light of null results from other experiments?We examine whether the annual modulation found by the DAMA dark matter experiment can be explained by Weakly Interacting Massive Particles (WIMPs), in light of new null results from other experiments. CDMS II has already ruled out most WIMP-nucleus spin-independent couplings as an explanation for DA...WIMP; Weakly interacting massive particles; DAMA; CDMS II; Parameter space2004-12
247 Mishchenko, Eugene; Raikh, Mikhail E.Zero-bias tunneling anomaly in a clean 2D electron gas caused by smooth density variationsWe show that smooth variations, δn(r), of the local electron concentration in a clean 2D electron gas give rise to a zero-bias anomaly in the tunnel density of states, v(ω), even in the absence of scatterers, and thus, without the Friedel oscillations. The energy width, ω0, of the anomaly scale...Tunnel density of states; Disordered metals2007-11
248 Miller, Joel StevenCollinear ferromagnetism and spin orientation in the molecule-based magnets M[N(CN)2]2 (M=Co,Ni)Zero-field unpolarized neutron powder diffraction has been used to study the low-T magnetic structure and T-dependent crystal structure of M[N(CN)2]2 (M=Co,Ni). Both compounds show collinear ferromagnetism with spin orientation along the c axis. The results provide the determination of a complete ma...Magnetic; Diffraction; Structure1999
249 Mattis, Daniel C.Anomaly in spin-wave spectrum of magnetic metalsIt is pointed out that in the band theory of magnetism the magnons have frequencies comparable to the Fermi energy. Therefore, in the calculation of the magnon spectrum of iron, nickel, cobalt, etc., it is the time- or frequency-dependent response function of the electrons which is used, and this ...Magnetic metals1966-11
250 Miller, Joel Steven; Epstein, Arthur J.Quest for molecule-based magnetsIn the past decade a new class of magnets possessing spins on organic species have been discovered and studied. These magnets can be fabricated at room temperature and may enable useful devices and/or processes. Herein we discuss several of the mechanisms that can enable the stabilization of magn...Mechanisms; Ferromagnetic; Spin coupling1996
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