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CreatorTitleDescriptionSubjectDate
301 Ehleringer, James R.Carbon isotope dynamics in Abies amabilis stands in the CascadesCarbon isotope ratios (d13C) of canopy air and carbon isotope discrimination at the ecosystem level were studied in three montane Pacific silver fir (Abies amabilis (Dougl. ex Loud.) Dougl. ex J. Forbes) stands, an old-growth and two younger stands. Spatial and temporal variations of canopy CO2 con...Carbon isotopes; Pacific silver fir; Carbon budget; Soil respiration; Cascade Mountains1998
302 Miller, Joel Steven; Epstein, Arthur J.Elastic properties of (N(CH3)3H) (I) (TCNQ)We present the results of a study of the temperature dependence of the Young's modulus and internal friction of (N(CH3 )3H)(I)(TCNQ). The Young's modulus was measured in a direction parallel to the TCNQ (tetracyanoquinodimethane) stacking axis using a vibrating reed technique. The results confirmed ...Metal-like, Conductivity, Magnetic1979
303 DeTar, CarletonLight quark spectrum with improved gauge and fermion actionsWe report on a study of the light quark spectrum using an improved gauge action and both Kogut-Susskind and Naik quark actions. We have studied six different lattice spacings, corresponding to plaquette couplings ranging from 6.8 to 7.9, with five to six quark masses per coupling. We compare the t...Quark spectrum; Kogut-Susskind quarks; Naik quarks1998-04
304 Blair, David F.Metal centers of cytochrome c oxidase: structures and interactionsStudies directed toward the elucidation of the structures of the metal centers in cytochrome c oxidase are reviewed. Progress towards an understanding of the interactions between these centers and their spatial distributions within the protein will also be presented. Our studies are based primarily...1983
305 Wu, Yong-ShiQuantum phase transition in a multicomponent Bose-Einstein condensate in optical latticesWe present a general lattice model for a multicomponent atomic Bose-Einstein system in an optical lattice. Using the model, we analytically study the quantum phase transition between the Mott insulator and a superfluid. A mean-field theory is developed from the Mott-insulator ground state. When the...Quantum phase transitions; Optical lattices; Bose-Einstein condensation; Boson-Hubbard model; Superfluids2003-01
306 Symko, Orest GeorgeTemperature dependence of the order parameter in a dilute AgMn spin glassThe magnetization of a dilute AgMn spin glass containing 150 ppm Mn has been measured over the temperature range from 20 mK to 2 K in an applied field of 0.9 Oe, using a SQUID magnetometer. A comparison of the measured magnetization with numerical calculations of the magnetization based on the Mean ...AgMn spin glass; Mean random field; MRF; Temperature dependence; Order parameter; RKKY interactions1982
307 Miller, Joel Steven; Epstein, Arthur J.Three-dimensional ordering, spin excitations, and dilution effects in the quasi-1-D ferromagnetic (DMeFc)(TCNE)The linear chain S = (1/2) molecular ferromagnet decamethylferrocenium tetracyanoethanide [(DMeFc) (TCNE)] has been studied by frequency-dependent ac susceptibility experiments. (X')(T) and (X") (T) exhibit maxima in the temperature range of 4.8 - 4.9 K, which corresponds to the transition tempe...Temperature; Transition; Magnetic1991
308 Hansen, Mark S.; Coffin, Cheryl M.; Capecchi, Mario R.Pax3:Fkhr interferes with embryonic Pax3 and Pax7 function: implications for alveolar rhabdomyosarcoma cell of origin.To investigate the role of the translocation-associated gene Pax3:Fkhr in alveolar rhabdomyosarcomas, we generated a Cre-mediated conditional knock-in of Pax3:Fkhr into the mouse Pax3 locus. Exploring embryonic tumor cell origins, we replaced a Pax3 allele with Pax3:Fkhr throughout its expression do...Neuroprogenitor; Embryogenesis2004-11-01
309 Vardeny, Zeev ValentineMagnetic field effects in ∏-conjugated polymer-fullerene blends: evidence for multiple componentsWe studied magnetoconductance (MC) and magnetoelectroluminescence (MEL) in organic diodes from blends of ∏-conjugated polymers and fullerenes at various concentrations, c. The MC response is composed of several components that depend on the applied bias voltage and c. A dominant positive low-field...pi-conjugated polymers; Fullerene blends; Magnetic field effects; Magnetoconductance; Magnetoelectroluminescence; MC; MEL; Organic magnetoresistance; OMAR; Organic diodes2008-12
310 Olivera, Baldomero M.; Bulaj, GrzegorzNovel conantokins from Conus parius venom are specific antagonists of N-methyl-D-aspartate receptorsWe report the discovery and characterization of three conantokin peptides from the venom of Conus parius. Each peptide (conantokin-Pr1, -Pr2, and -Pr3) contains 19 amino acids with three γ-carboxyglutamate (Gla) residues, a post-translationally modified amino acid characteristic of conantokins. The...Conotoxins; Conantokins; Conus parius; Antagonists; n-methyl-D-aspartate receptors2007
311 Vardeny, Zeev ValentinePhotoexcitation dynamics in regioregular and regiorandom polythiophene filmsUsing a variety of optical probes techniques we studied the photoexcitation dynamics in thin films of poly-3-hexyl thiophene with regioregular order that forms lamellae structures with increased interchain interaction, as well as regiorandom order that keeps a chainlike morphology. In regiorandom fi...Photoexcitation dynamics; Regio-regular; Regio-random; Polythiophene films2001-11
312 Wu, Yong-ShiMultisheet configuration space and fractional quantum statisticsWe show that if one uses a multisheet configuration space for a system of identical particles, then fractional quantum statistics in two dimensions can be geometrically characterized as a topological quantum number for going from one sheet to the next. Furthermore, the spectrum of such a g-sheet s...1992-05
313 Capecchi, Mario R.Male fertility is dependent on dipeptidase activity of testis ACE.Testis angiotensin-converting enzyme (ACE) is an isozyme exclusively expressed by developing sperm. This protein has only a single catalytic domain containing the HEXXH consensus-site motif typical of zinc metallopeptidases. The exact role of testis ACE is unknown, but male mice lacking the protein ...Amino Acid Motifs; Blotting, Western; Catalytic Domain; Comparative Study; Isoenzymes; Protein Structure, Tertiary2005-11-11
314 Miller, Joel Steven; Epstein, Arthur J.Photoinduced magnetization in the organic-based magnet Mn(TCNE)x.y(CH2Cl2)Photoinduced magnetization in a magnet based on organic species is reported for the first time. Upon optical excitation in the blue region of spectrum, Mn (tetracyanoethylene)x .y(CH2Cl2) (x=2,y-0.8) exhibits increased magnetic susceptibility at temperatures as high as 75 K, accompanied with photo-i...Absorption; Magnetic; Infrared2002
315 Armentrout, Peter B.Collision-induced dissociation dynamics of the [OCS • C2H2]+ complex. A combined experimental and theoretical studyCollision-induced dissociation (CID) of the [OCS • C2H2]+ complex ion with both Xe and Ar over an energy range of 0 to 10 eV in the center of mass frame is studied using a guided ion beam tandem mass spectrometer. The cross sections of the ionic products observed (C,H2S+, OCS+, C2HJ, and S+) are ...Collision-induced dissociation; Competitive shift; Ethylene Sulfide cation; Kinetic shift; Thioketene cation; Potential energy surface2000
316 Williams, Clayton C.High-resolution photothermal laser probeAn advance in photothermal imaging is described. A photothermal laser probe is presented that operates at a frequency of 1 GHz. At this frequency the spacial resolution is limited only by the optical spot size of the probe beam. The photothermal sensitivity of the probe is 1.2 X 10-4 degrees Celsiu...Laser probes1985
317 Coley, Phyllis D.Guía de los arboles comunes del Parque Nacional Soberanía, PanamáEsta es una guía con dibujos para las cincuenta especies de árboles más comunes del bosque tropical en los alrededores del Parque Soberanía, Panamá. También se incluyen siete especies de hierbas y cuatro herbáceas grandes que sobresalen en el sotobosque (bosque bajo). Aunque en el área del p...Arboles; Arbustos1984
318 Vardeny, Zeev ValentineRandom lasing in human tissuesA random collection of scatterers in a gain medium can produce coherent laser emission lines dubbed "random lasing." We show that biological tissues, including human tissues, can support coherent random lasing when infiltrated with a concentrated laser dye solution. To extract a typical random reson...Random lasing; Gain medium; Human tissues; Malignant tissues2004
319 Goller, FranzBilateral syringeal contributions to song in the zebra finchAlthough central control of song production has been investigated extensively in the zebra finch (Taeniopygia guttata), much less is known about peripheral vocal motor dynamics during song.Electromyographic activity; Sound souces; Unilateral2004
320 Wu, Yong-ShiQuiver matrix mechanics for IIB string theory (II): generic dual tori, fractional matrix membrane and SL(2, Z) dualityWith the deconstruction technique, the geometric information of a torus can be encoded in a sequence of orbifolds. By studying the Matrix Theory on these orbifolds as quiver mechanics, we present a formulation that (de)constructs the torus of generic shape on which Matrix Theory is "compactified". T...2005-02
321 Morse, Michael DavidOptical spectroscopy of jet-cooled NiSiThe electronic states of gaseous diatomic NiSi have been investigated using the combined techniques of resonant two-photon ionization spectroscopy, dispersed fluorescence spectroscopy, and density functional computations. A single electronic band system, designated as the [8.0]1?X 1?+ system, has be...2003
322 Symko, Orest GeorgeSpin-glass transition of a dilute Ag-Mn alloy in a magnetic fieldThe spin-glass state in a magnetic field is studied in a very dilute Ag-Mn sample containing 150 ppm of Mn. The field-cooled magnetization of this system is investigated over temperatures ranging from 4 down to 0.01 K in magnetic fields from 932 to 1 Oe. Scaling is observed in the nonlinear suscepti...Spin-glass transition; Spin-glass state; Ag-Mn alloy; Silver-manganese alloy1986-01
323 Capecchi, Mario R.Choose your target.The technology of modifying endogenous genes has recently been extended from mice to Drosophila and sheep. Concurrently, genomic sequencing is uncovering thousands of previously uncharacterized genes. Armed with today's technologies, what are our best options for delineating the functions of these n...Animals; Mice; Sheep2000-09-13
324 DeTar, CarletonLattice calculation of 1-+ hybrid mesons with improved Kogut-Susskind fermionsWe report on a lattice determination of the mass of the exotic 1-+ hybrid meson using an improved Kogut-Susskind action. Results from both quenched and dynamical quark simulations are presented. We also compare with earlier results using Wilson quarks at heavier quark masses. The results on lattice...Staggered quarks; Kogut-Susskind fermions2003-10
325 Vardeny, Zeev ValentineLaser action in polydialkylfluorene films: influence of low-temperature thermal treatmentWe have used a variety of optical probes to investigate the changes occurring upon low-temperature thermal treatment to the emissive properties of dialkyl substituted polyfluorene thin films. We found that the low-temperature-driven morphological changes involving aggregates formation, which are ob...Laser action; Polydialkylfluorene films; pi-conjugated polymers; Thermal treatment1999
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