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CreatorTitleDescriptionSubjectDate
226 Ailion, David CharlesCommensurability and defect-induced phason gaps in incommensurate systemsThe phason energy gap has been observed to increase on going from the incommensurate to higher-order commensurate phases in the "devil's staircase" compound [N(CH3)4]2ZnCl4. The gap was determined via the phason-induced 1 4N spin-lattice relaxation contribution, which was obtained from the variati...Phasons; Commensurate; Incommensurate; Lattices; Modulation1985
227 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Comment on "Frequency response and origin of the spin-½ photoluminescence-detected magnetic resonance in a ∏-conjugated polymerIn a recent paper, Segal et al. [Phys. Rev. B 71, 245201 (2005)] advanced a new explanation for the dynamics of spin-1/2 photoluminescence-detected magnetic resonance (PLDMR) in films of a rr-conjugated polymer, namely, a soluble derivative of poly(phenylene-vinylene) (MEH-PPV), using a model [dubbe...Photoluminescence-detected magnetic resonance; PLDMR; pi-conjugated polymers; Poly(phenylene-vinylene); MEH-PPV2007-06
228 Mattis, Daniel C.Comment on "Ground-state properties of a spin-1 antiferromagnetic chainBotet and Jullien [Phys. Rev. B 27, 613 (1983)] and Botet, Jullien, and Kolb [Phys. Rev. B 28, 3914 (1983)] performed a finite-size scaling analysis of the spin-1 antiferromagnetic Heisenberg-Ising chain. Their work was criticized by Bonner and Mtiller [Phys. Rev. B 29, 5216 (1984)] on the grounds...Antiferromagnets; Ground-state; Ising chain; Energy gap1985-04
229 Vardeny, Zeev ValentineComment on "Large optical nonlinearity of semiconducting single-walled carbon nanotubes under resonant excitations"In a recent Letter Maeda et al. studied the optical nonlinearities of single-walled carbon nanotubes (SWNT) films using both ??Z-scan?? and ??pump and probe?? (PP) techniques with ~100 fs time resolution [1]. They found that SWNTs have a large resonant third-order nonlinear optical susceptibili...SWNT; Coherent artifact2006
230 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Comment on "Yield of singlet excitons in organic light-emitting devices: a double modulation photoluminescence-detected magnetic resonance study"In a recent Letter [1] Lee et al. studied the spin 1/2 photoluminescence-detected magnetic resonance (PLDMR) of a soluble derivative of poly-phenylene vinylene [MEH-PPV] using a double modulation scheme, where both the laser excitation intensity and the microwave power were modulated at ?ex and ?...Singlet excitons; PLDMR; Poly-phenylene vinylene; MEH-PPV; Quenching; Spin dependent recombination; OLED2006
231 Saam, BrianComment on pressure dependence of wall relaxation in polarized 3He gaseous cellsZheng et al. [Zheng, Gao, Ye, and Zhang, Phys. Rev. A 83, 061401(R) (2011)] have measured a strong linear pressure dependence of the nuclear relaxation rate of 3He in glass cells typically used to generate and/or store polarized 3He at room and cryogenic temperatures. Their interpretation is that th...2012-01-01
232 Saam, BrianComment on: New limit on lorentz-invariance- and CPT-violating neutron spin interactions using a free-spin-precession 3He- 129Xe comagnetometerIn Ref. [1], the authors use a classical result for the magnetic field created by a uniform magnetization to analyze the effects of magnetic interactions between 3He and 129Xe nuclear spins. We point out that the classical result is not applicable for interaction between nuclear spins: the actual in...2014-01-01
233 Clayton, Dale H.Common grackle anting with lime fruit and its effect on ectoparasitesAnting is stereotyped behavior in which birds ex- pose themselves to fluid-secreting ants or other pun- gent substances. During "active" anting a bird crush- es an ant in the bill and rubs it frenetically through its plumage (Rothschild and Clay 1952). During "passive" anting a bird entices ants to ...Quiscalus quiscala; Columbicola columbae; Anting; Ectoparasites1993
234 Armentrout, Peter B.Communication: Theoretical exploration of Au++ H2, D2, and HD reactive collisionsA quasi-classical study of the endoergic Au+(¹S) + H₂(X¹Σ+g) → AuH+ (²Σ+) + H(²S) reaction, and isotopic variants, is performed to compare with recent experimental results [F. Li, C. S. Hinton, M. Citir, F. Liu, and P. B. Armentrout, J. Chem. Phys. 134, 024310 (2011)]. For this purpose, a ...2011
235 Clayton, Dale H.Comparative effects of mites and lice on the reproductive success of rock doves (Columba livia)We report experimental data comparing the effects of Mesostigmatid mites and Ischnoceran lice on the reproductive performance of a single group of captive rock doves (Columba livid). Several components of host reproductive success were compared for the two groups, including number of eggs laid, hatc...Ectoparasites; Reproduction; Rock doves; Columba livia; Ischnocera; Mites; Lice1995
236 Davidson, Diane W.Comparative structure of harvester ant communities in arid Australia and North AmericaIn the Australian arid zone, the species richness of ants is greater and that of mammalian granivores is less than in North American deserts. This study aimed to determine if the structure of harvester ant communities differs from that seen in North American deserts, focussing on differences relate...Species; Rodents; Diversity1988
237 Clayton, Dale H.; Bush, Sarah ElizabethComparative transmission dynamics of competing parasite speciesCompetition-colonization trade-off models explain the coexistence of competing species in terms of a trade-off between competitive ability and the ability to colonize competitor-free patches of habitat. A simple prediction of these models is that inferior competitors will be superior dispersers. Thi...Bird lice; Campanulotes compar; Coexistence; Colonization; Columba livia; Columbicola columbae; Competition; Dispersal; Parasite; Phoresis; Specificity; Pseudolynchia canariensis; Phthiraptera2008
238 Sokolsky, PierreComparison of air fluorescence and ionization measurements of E.M. shower depth profiles: test of a UHECR detector techniqueMeasurements are reported on the fluorescence of air as a function of depth in electromagnetic showers initiated by bunches of 28.5 GeV electrons. The light yield is compared with the expected and observed depth profiles of ionization in the showers. It validates the use of atmospheric fluorescence...Air fluorescence; Electromagnetic shower; Ultra-high energy cosmic rays; Ionization2006-02
239 Hultine, KevinComparison of methods to estimate Ephemeral Channel Recharge, Walnut Gulch, San Pedro River Basin, ArizonaEphemeral channel transmission loss represents an important groundwater surface water exchange in arid and semiarid regions and is potentially a significant source of recharge at the basin scale. Copyright [year] American Geophysical Union. Reproduced by permission of American Geophysical Union. ...Transport; Transmission; Balance2004
240 Beckerle, Mary C.Comparison of three members of the cysteine-rich protein family reveals functional conservation and divergent patterns of gene expressionMembers of the cysteine-rich protein (CRP) family are evolutionarily conserved proteins that have been implicated in the processes of cell proliferation and differentiation. In particular, one CRP family member has been shown to be an essential regulator of cardiac and skeletal muscle development.LIM domains; Chicken fibroblasts; Zyxin; Actinin; Protein expression; Cysteine-rich proteins1997
241 Gondolo, PaoloCompatibility of DAMA dark matter detection with other searchesWe present two examples of velocity distributions for light dark matter particles that reconcile the annual modulation signal observed by DAMA with all other negative results from dark matter searches. They are: (1) a conventional Maxwellian distribution for particle masses around 5 to 9 GeV; (2) ...DAMA; CDMS; Neutralinos; WIMP; Weakly interacting massive particles; Halo models; Dark matter stream2005-06
242 Davidson, Diane W.Competition and the structure of granivore communitiesWe trace the development of our investigations of granivory in desert ecosystems, illustrating the synthesis of the comparative and experimental approaches and noting the essential contributions of both. In the process, we also call attention to several major difficulties inherent to experimentatio...Granivory; Competition; Desert Ecosystems; Competitive investigations; Experimental investigations1980
243 Miller, Joel Steven; Epstein, Arthur J.Complex ac susceptibility studies of the disordered molecular based magnets V(TCNE)x: role of spinless solventThe effect of different spinless solvents on the magnetism of V(TCNE)x . y(solvent) (TCNE= tetracyanoethylene) is studied by temperature (T) dependent ac susceptibility above 2.3 K. Though V(TCNE)x.y(CH2Cl2) has a critical temperature Tc -400 K, for V(TCNEx.y(C4H8O), Tc -205 K and the coercive field...Magnetization; Spin; Temperature1993
244 Greene, Stephen Andrew; Golden, Kenneth M.Composite microstructures and climate changeDevelop mathematical models to better understand the changes in sea ice as it pertains to global climate. Compare Diffusion Limited Aggregates (DLA) and Electrorheological (ER) fluids to sea ice microstructures.Composite microstructures; Climate change; Effect on climate; Trapeze Interactive Poster2010-03-15
245 Fleming Aaron M.Computational studies of electronic circular dichroism spectra predict absolute configuration assignments for the guanine oxidation product 5-carboxamido-5-formamido-2-iminohydantoinOxidation of the guanine heterocycle by two electrons can yield the chiral product 5-carboxamido-5-formamido-2-iminohydantoin (2Ih). The 2Ih free base enantiomers were synthesized from 2'-deoxyguanosine oxidized with a Cu(II)/H2O2 oxidant system followed by hydrolysis of the N-glycosidic bond. These...Guanine oxidation; 2-Iminohydantoin; Electronic circular dichroism; Time-dependent density functional theory2014-12-15
246 Olivera, Baldomero M.; Parks, Thomas N.Conantokin-T: a γ-carboxyglutamate containing peptide with N-methyl-D-aspartate antagonist activityConantokin-T, a 21-amino acid peptide which induces sleep-like symptoms in young mice was purified from the venom of the fish-hunting cone snail, Conus tulipa. The amino acid sequence of the peptide was determined and verified by chemical synthesis. The peptide has 4 residues of the modified amino ...Conotoxins; Conantokin-T; N-methyl-D-aspartate antagonist; Conus tulipa1990
247 Seger, JonConditional relatedness, recombination, and the chromosome numbers of insectsIf two polymorphic loci are out of phase equilibrium, a homozygote at one of these loci is more highly related to its kin, at the other locus, than is an equivalent heterozygote. As a result, selection can favor (1) phenotypic responses to relative heterozygosity, and (2) increased recombination bet...Coefficients of relatedness; Conditional relatedness1983
248 Mattis, Daniel C.Conductivity of one-dimensional interacting fermions*Using an exactly soluble model, the decay rate of a current-carrying state of one-dimensional fermions is calculated in the presence of random scatterers at finite temperature and the dc conductivity thereby inferred. For interacting fermions it is modified by a factor (T/T + θ)g, where g is a posi...Fermi gas1974-04
249 Vardeny, Zeev ValentineConfined and delocalized polarons in ∏-conjugated oligomers and polymers: a study of the effective conjugation lengthWe studied optical absorption of polarons in ∏-conjugated oligomers and polymers using the photoinduced absorption technique as well as chemical doping spectra from the literature. We find that the photon energy of the polaron low-energy transition obeys a relationship that depends only on the oli...Confined polarons; Delocalized polarons; pi-conjugated oligomers; pi-conjugated polymers; Effective conjugation length2004-06
250 Blumenthal, Donald K.; Trewhella, JillConformationally dynamic C helix of the RIalpha subunit of protein kinase A mediates isoform-specific domain reorganization upon C subunit binding.Different isoforms of the full-length protein kinase A (PKA) regulatory subunit homodimer (R2) and the catalytic (C) subunit-bound holoenzyme (R2C2) have very different global structures despite similar molecular weights and domain organization within their primary sequences. To date, it has been th...Protein Isoforms; Global Structures; cAMP2005-10-21
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