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CreatorTitleDescriptionSubjectDate
326 Dawson, KyleRadiation tolerance of fully-depleted P-channel CCDs designed for the SNAP satelliteThick, fully depleted p-channel charge-coupled devices (CCDs) have been developed at the Lawrence Berkeley National Laboratory (LBNL). These CCDs have several advantages over conventional thin, n-channel CCDs, including enhanced quantum efficiency and reduced fringing at near-infrared wavelengths an...P-Channel CCDs; SNAP satellite; Space-based telescopes2008-06
327 Beckerle, Mary C.Molecular dissection of zyxin function reveals its involvement in cell motilitySpatially controlled actin filament assembly is critical for numerous processes, including the vectorial cell migration required for wound healing, cell-mediated immunity, and embryogenesis. One protein implicated in the regulation of actin assembly is zyxin, a protein concentrated at sites where t...Zyxin; Actinin; Ena/VASP1999
328 Gondolo, PaoloAGAPEROS: searching for microlensing in the LMC with the pixel method. I. Data treatment and pixel light curves productionRecent surveys monitoring millions of light curves of resolved stars in the LMC have discovered several microlensing events. Unresolved stars could however signi _x000C_cantly contribute to the microlensing rate towards the LMC. Monitoring pixels, as opposed to individual stars, should be able to ...Data analysis techniques; Halo; Galaxies; Gravitational lensing; Pixel method; Large Magellanic Cloud; LMC1999
329 Gerton, JordanDipolar relaxation collisions in magnetically trapped 7LiWe report the measurement of the rate constant for dipolar relaxation from the (F=2, mF=2) hyperfine state of 7Li. The atoms are confined in a permanent magnet trap at a field of 10^3 G. The measured value of (1.05±0.10)X10^-14 cm3/s agrees well with theory. Additionally, we determine an upper bo...1999-02
330 Symko, Orest GeorgeTunneling studies of mesoscopic all-NBN junctionsA scanning tunneling microscope (STM) was used to position a NbN tip near a NbN thin film sputtered on a Si substrate. Measurements at 4.2 K clearly show an energy gap of 5.0 mV. The Coulomb blockade of tunneling and the Coulomb staircase, formed by single-electron charging of the central electrod...All-NbN junctions; NbN1993-03
331 Vardeny, Zeev Valentine; Symko, Orest GeorgeQuasiparticle relaxation in high-Tc superconductorRecent measurements by Eesley et al. [1] of transient reflectivity in superconducting Tl2Ba2Ca2Cu30io were interpreted as evidence for order-parameter relaxation in the vicinity of Tc, which was analyzed in terms of BCS weak coupling for ?(r)/?(0). In this Comment we question this interpretation ...Quasiparticle relaxation1991
332 Armentrout, Peter B.Translational energy dependence of O+(4S) + N2 → NO+ + N from thermal energies to 30 eV c.m.Guided ion beam mass spectrometry is used to examine the kinetic energy dependence of the reaction of ground state atomic oxygen ion with molecular nitrogen. An 0 + (4S) source which produces less than 0.06% excited states is described. Cross sections for the NO+ + N product channel decrease with...Ion-molecule reactions; Translational energy; Threshold behavior; Endothermic reactions; Nitrogen; Oxygen1987
333 Gondolo, PaoloStellar orbit constraints on neutralino annihilation at the galactic centerDark matter annihilation has been proposed to explain the TeV gamma rays observed from the Galactic Center. We study constraints on this hypothesis coming from the mass profile around the Galactic Center measured by observing stellar dynamics. We show that for several proposed WIMP candidates, the...Neutralinos; Annihilation2006-09
334 Adler, Frederick R.; Jackson, Brian Richard; Carroll, Karen C.; Samore, Matthew H.Use of strain typing data to estimate bacterial transmission rates in healthcare settingsOBJECTIVE: To create an affordable and accurate method for continuously monitoring bacterial transmission rates in healthcare settings. DESIGN: We present a discrete simulation model that relies on the relationship between in-hospital transmission rates and strain diversity. We also present a proof...Strain typing; Infection control; Transmission model2005
335 Vardeny, Zeev ValentineUltrafast spectroscopy of excitons in single-walled carbon nanotubesWe studied the femtosecond dynamics of photoexcitations in films containing semiconducting and metallic single-walled carbon nanotubes (SWNTs), using various pump-probe wavelengths and intensities.We found that confined excitons and charge carriers with subpicosecond dynamics dominate the ultrafas...Ultrafast spectroscopy; Excitons; Single-walled carbon nanotubes; SWNT2004-01
336 Gondolo, PaoloDetectability of the Sgr dwarf leading tidal stream with Auger, EUSO, or OWLWe point out that if heavy metastable particles composing the dark matter of our galaxy are responsible for the ultrahigh energy cosmic rays (UHECR) then the leading tidal stream of the Sagittarius dwarf galaxy could be detected through UHECR. The signal would be an anisotropy in the UHECR flux sma...Sagittarius dwarf galaxy; Sgr stream; anisotropy2004-07
337 Sokolsky, PierreFirst observation of the Greisen-Zatsepin-Kuzmin suppressionThe High Resolution Fly's Eye (HiRes) experiment has observed the Greisen-Zatsepin-Kuzmin suppression (called the GZK cutoff) with a statistical significance of five standard deviations. HiRes' measurement of the flux of ultrahigh energy cosmic rays shows a sharp suppression at an energy of 6 x 10^1...Extensive air showers; Suppression; Energy spectrum; Fluorescence; GZK cutoff2008-03
338 Davidson, Diane W.Pruning of host plant neighbors by ants: an experimental approachSome ants of myrmecophytic plants either obligately or facultatively prune vegetation surrounding their host trees. Pruning behavior occurs at higher frequency in ants with sting defenses than in those with chemical defenses, which may generally convey an advantage in aggressive encounters between a...Allelopathy; Allomerus demararae; Ant-plant interactions; Ants; Cordia nodosa; Crematogaster; Mutualism; Peru; Plant-animal interaction; Pseudomyrmex; Triplaris americana1988
339 Carter, Tony M.Cascade: hardware for high/variable precision arithmeticThe Cascade hardware architecture for high/variable precision arithmetic is described. It uses a radix-16 redundant signed-digit number representation and directly supports single or multiple precision addition, subtraction, multiplication, division, extraction of the square root and computation...1989
340 Miller, Joel StevenCharacterization of novel TCNQ and TCNE 1 : 1 and 1 : 2 salts of the tetrakis(dimethyamino) ethylene dication, [{(CH3)2N}2C-C{N(CH3)2}2]2+Addition of TCNQ to a solution of tetrakis(dimethylamino)ethylene in MeCN produces the salt [TDAE][TCNQ]2; the dipositive cation, [{(CH3)2N}2C-C{N(CH3)2}2]2+, is nonplanar, with a dihedral angle of 63.9(o), while the TCNQ anions crystallize as [TCNQ]2 2- dimers with an interplanar separation of 3.1...Electron; Oxidations; Transfer1996
341 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
342 Symko, Orest GeorgeBackground signals in SQUID magnetometersSince a SQUID magnetometer is an extremely sensitive device capable of detecting minute magnetic flux changes in a sample, it will also detect unwanted signals from materials near the magnetometer. The presence of temperature dependent "background signals" limits the accuracy of measurements of ...SQUID magnetometer; Background signals1974
343 Symko, Orest GeorgeSpin-glass behavior in dilute magnetic alloys with hcp structureA simple physical model is presented for calculating the magnetization of dilute magnetic systems with hep hosts which incorporates elements of both crystal-field theory and the molecular-field theory of spin-glasses. To permit the computation of the Ruderman-Kittel-Kasuya-Yosida contribution, the i...Spin-glass behavior; HCP structure; HCP alloys; Dilute magnetic systems; Molecular-field theory; MgMn; ZnMn1982-05
344 Gerton, JordanPhase-contrast imaging of atomic superfluid state in degenerate gas of 6Li atomsThe recent experimental realizations of Bose-Einstein condensation in trapped ultracold atomic gases composed of bosonic alkali atoms has generated a broad interest in studying different properties of these degenerate atomic Bose systems. Although the degenerate atomic gas composed of fermionic atom...1998
345 Mattis, Daniel C.Phonons and phase transitions of heliumWe find a new collective shear-wave-like mode above Tλ, merging with the longitudinal acoustic mode at a higher critical temperature. The speed of the new sound wave is predicted to vanish near Tλ as s ∞ (T -Tλ)½ .1973-06
346 Vardeny, Zeev ValentineDetection of electronic excited states in conjugated polymers by picosecond transient strain spectroscopyWe describe a new type of spectroscopy based on picosecond transient strain in absorption photomodulation that can be used to detect and identify both allowed and forbidden optical transitions in solid thin films. We have applied the new spectroscopy to a variety of conducting polymer films such as ...Picosecond transient strain spectroscopy1995-02
347 Jorgensen, ErikNeural plasticityNeural plasticity refers to functional changes in the nervous system and therefore encompasses a range of phenomena from changes at synapses observed on a microscopic scale to changes in behavior observed in the whole animal. These diverse phenomena are related since changes in synapses are believ...Synapses; Nervous System; Development1997
348 Vardeny, Zeev ValentineMagneto-optical studies of photoexcitations in C61We have used a variety of cw optical and optically detected magnetic-resonance techniques to characterize long-lived photoexeitations in methanofullerene (C6 1) as a dispersion in polystyrene glass, at temperatures below 10 K. We identify triplet excitons with zero-field-splitting (ZFS) parameters...Photoexcitations; C61; Methanofullerene1993-12
349 Wu, Yong-ShiRemarks on fractional statisticsSome issues in the theory of fractional (or intermediate) statistics are discussed with an eye on possible applications to the quantum Hall effect: spins and statistics of clusters, invariant characterization of statistics, and the effect of space topology.Fractional statistics1985-01
350 Kieda, David B.High resolution charge measurements of UH cosmic ray nuclei using a direct imaging Cherenkov ground-based observatoryThe accurate determination of the elemental composition of cosmic rays at high energies is expected to provide crucial clues on the origin of these particles. Here we discuss a technique that has become possible through the use of modern ground-based Cherenkov imaging detectors. We combine a measure...Cherenkov light; Quark star; UH nuclei; Magnetic monopole2003
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