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CreatorTitleDescriptionSubjectDate
226 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
227 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
228 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
229 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
230 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
231 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
232 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
233 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
234 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
235 Adler, Frederick R.Effect of 1918 PB1-F2 expression on influenza A virus infection kineticsRelatively little is known about the viral factors contributing to the lethality of the 1918 pandemic, although its unparalleled virulence was likely due in part to the newly discovered PB1-F2 protein. This protein, while unnecessary for replication, increases apoptosis in monocytes, alters viral po...2011
236 Vardeny, Zeev ValentineTransient spectroscopy of Frenkel and charge transfer excitons in α-sexithienyl filmsPhotoexcitations dynamics are investigated in a-sexithienyl nanocrystalline films using transient photomodulation in a spectral range from 0.4 to 2.5 eV and time domain from 200 fs to 50 ms. We identify intrachain and interchain excitations. The former are even parity excitons with ultrafast dynami...Transient spectroscopy; Excitons; Frenkel exciton; Charge transfer exciton; Transient photomodulation1997-10
237 Sperry, John S.Relationship between xylem conduit diameter and cavitation caused by freezingThe centrifuge method for measuring the resistance of xylem to cavitation by water stress was modified to also account for any additional cavitation that might occur from a freeze-thaw cycle. A strong correlation was found between cavitation by freezing and mean conduit diameter.Embolism; freezing stress; hydraulic conductivity1999
238 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Photomodulation spectroscopy of iodine-doped polyacetylene; phase transition from soliton lattice to metalUsing the photomodulation technique for iodine I3-)-doped polyacetylene, we have found spectroscopic evidence for an abrupt phase transition at 5% I3-. The transition is from the lightly doped phase best described as soliton lattice to the heavily doped metallic phase. The phase transition is chara...Photomodulation spectroscopy; Iodine-doped polyacetylene1986-10
239 Vardeny, Zeev ValentinePlastic microring lasers on fibers and wiresPhotopumped, pulsed, narrow line laser emission is demonstrated using cylindrical microcavities formed by p-conjugated polymer thin films wrapped around thin glass optical fibers and metal wires with various diameters D. A variety of cavity-dependent resonant laser mode structures were observed, whi...Microring lasers; pi-conjugated polymers; pi-conjugated polymer thin films; Microcavities1998
240 Bastiani, MichaelPathfinding by growth cones in the central nervous system of the grasshopper embryoIn the grasshopper embryo the morphological development of individually identified neurons can be traced prior to the onset of axonogenesis on through maturity (eg., Goodman and Spitzer, 1979). The behavior of individual growth cones can be characterized in their natural environment as they extend t...1982-06-03
241 Vardeny, Zeev ValentineOptical bias control of dispersive relaxations in α-Si:HRelaxation of the photoinduced ir absorption band in α-Si:H was studied in the microsecond time domain as a function of cw bias illumination. The decays follow a power law t-α where the dispersion parameter a increases with bias illumination. At low temperatures, a increases linearly with the st...Optical bias control; Dispersive relaxations; a-Si:H; Amorphous silicon1984-01
242 Mattis, Daniel C.New mapping for particles on lattices with hard-core interactionsA novel mapping between Hilbert spaces of unequal dimensionalities yields many-body states which exactly satisfy the no-double-occupancy constraints for particles on lattices in arbitrary spatial dimensions. After proving the states are complete, we apply them to Nagaoka's theorem and the t-J model...Ferromagnetism; Spin; Dimensions1996
243 Poulter, Charles Dale; Jiang, YunfengBTS1 encodes a geranylgeranyl diphosphate synthase in Saccharomyces cerevisiaeProtein prenylation utilizes different types of isoprenoids groups, namely farnesyl and geranylgeranyl, to modify proteins. These lipophilic moieties attach to carboxyl-terminal cysteine residues to promote the association of soluble proteins to membranes. Most prenylated proteins are geranylgeranyl...Amino Acid Sequence; Cloning, Molecular; Gene Expression1995-09-15
244 Symko, Orest GeorgeMicrowave absorption in the superconducting and normal phases of Y-Ba-Cu-OMicrowave absorption in a dc magnetic field up to 12 kG, attributed to nonequilibrium contributions to the ac susceptibility, appears at Tc as the sample is cooled. ESR measurements of YBa-Cu-O show that Cu2+ exists only in the fraction of the sample which is not superconducting in a distorted octa...Microwave absorption; Superconducting phase; YBCO; High Tc1987-08
245 Miller, Joel Steven; Epstein, Arthur J.Local structural order in the disordered vanadium tetracyanoethylene room-temperature molecule-based magnetWe determined the vanadium oxidation state and local coordination environment in disordered samples of magnetic V[TCNE]x(x=2) prepared by chemical vapor deposition (CVD). Systematic studies of the x-ray absorption near-edge structure (XANES) in this material and reference compounds show that V ions ...Magnetic; Solvent; Structure2004
246 Morse, Michael DavidSpectroscopy and electronic structure of jet-cooled NiCuDiatomic nickel-copper, NiCu, has been investigated by resonant two-photon ionization spectroscopy in a jet-cooled molecular beam. Six band systems have been identified over the range 11 500-16 500 cm-1. The ground state of NiCu has been determined to be X 2?5/2, with ?"e = 273.01 ? 1.15 cm-1, ?"exe...1988
247 Wu, Yong-ShiRemarks on noncommutative open string theory: V duality and holographyIn this paper we study the interplay of electric and magnetic backgrounds in determining the decoupling limit of coincident D branes towards a noncommutative Yang-Mills (NCYM) or open string (NCOS) theory. No decoupling limit has been found for the NCYM model with space-time noncommutativity. It i...Hubbard operator; Bosonization; Deformation; t-J model2001-03
248 Voth, Gregory AlanQuantitative assessment of the accuracy of centroid molecular dynamics for the calculation of the infrared spectrum of liquid waterA detailed analysis of the infrared lineshapes corresponding to the intramolecular bond vibrations of HOD in either H2O or D2O is presented here in order to quantitatively assess the accuracy of centroid molecular dynamics in reproducing the correct features of the infrared spectrum of water at amb...2010
249 Capecchi, Mario R.Lack of angiotensin II-facilitated erythropoiesis causes anemia in angiotensin-converting enzyme-deficient miceWhile nephrologists often observe reduced hematocrit associated with inhibitors of angiotensin-converting enzyme (ACE), the basis for this effect is not well understood. We now report that two strains of ACE knockout mice have a normocytic anemia associated with elevated plasma erythropoietin level...2000
250 Armentrout, Peter B.The simplest b 2 + ion: determining its structure from its energetics by a direct comparison of the threshold collision-induced dissociation of protonated oxazolone and diketopiperazineEnergy-resolved collision-induced dissociation of b2 + ions derived from protonated GGG and GAG are compared with that of protonated diketopiperazine (H+DKP). Absolute dissociation cross sections are obtained using a guided ion beam tandem mass spectrometer and analyzed using statistical methods. T...2012
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