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CreatorTitleDescriptionSubjectDate
251 Malloy, Thomas E.Logic of logic and the logic of dreams.For Bateson explanation is the mapping of description onto tautology. "An explanation has to provide something more than a description provides, and in the end, an explanation appeals to a tautology, which as I have defined it, is a body of propositions so linked together that the links between the ...Science; Psychology; Dreams2006-02
252 Rogachev, AndreyMagnetic-field enhancement of superconductivity in ultranarrow wiresWe study the effect of an applied magnetic field on sub-10-nm wide MoGe and Nb superconducting wires. We find that magnetic fields can enhance the critical supercurrent at low temperatures, and do so more strongly for narrower wires. We conjecture that magnetic moments are present, but their pair-...Ultranarrow wires; Magnetic-field enhancement2006-09
253 Harrison, Reid R.; Tabib-Azar, MassoodMicrocontroller-based wireless recording unit for neurodynamic studies in saltwaterThis paper presents the design of a biocompatible implantable neural-recording unit for Aplysia californica, which is a common sea slug. Low-voltage extracellular neural signals (< 250 μV) are recorded using a high-performance low-power low-noise preamplifier that is packaged with programmable dig...Sea slug; Data acquisition; Implantable; Low-noise amplifier; Low-power circuits; Neural sensor; Telemetry2006-10
254 Horch, Kenneth W.Microfabricated cylindrical multielectrodes for neural stimulationThe effects of spinal cord injuries are likely to be ameliorated with the help of functional electrical stimulation of the spinal cord, a technique that may benefit from a new style of electrode: the cylindrical multielectrode. This paper describes the specifications for, fabrication techniques for...Cylindrical multielectrode; Depth electrodes; Impedance testing; Microelectromechanical systems (MEMS); Microstimulation; Impedance testing; Neural prosthesis2006-02
255 Furse, Cynthia M.Multicarrier reflectometryA new reflectometry method called multicarrier reflectometry (MCR) for fault location in cables is proposed. MCR combines a weighted set of sinusoidal excitations into a signal that is sent down the wire. The reflected signal from the cable under test is analyzed in order to determine the length of ...Multicarrier reflectometry; MCR; Fault location2006-06
256 Khan, Faisal HabibMultilevel modular capacitor clamped DC-DC converterA novel topology of multilevel modular capacitor clamped dc-dc converter (MMCCC) will be presented in this paper. In contrast to the conventional flying capacitor multilevel dc-dc converter (FCMDC), this new topology is completely modular and requires a simpler gate drive circuit. Moreover, the new ...Capacitor-clamped converter; DC-DC converter; MMCCC; Multilevel modular capacitor2006-12
257 Gondolo, PaoloNeutralino with the right cold dark matter abundance in (almost) any supersymmetric modelWe consider nonstandard cosmological models in which the late decay of a scalar field Ø reheats the Universe to a low reheating temperature, between 5 MeV and the standard freeze-out temperature of neutralinos of mass mx. We point out that in these models all neutralinos with standard density Ώstd...Neutralinos; Reheating temperature2006-07
258 Bernstein, Paul S.; Gellermann, WernerNonmydriatic fluorescence-based quantitative imaging of human macular pigment distributions.We have developed a CCD-camera-based nonmydriatic instrument that detects fluorescence from retinal lipofuscin chromophores ("autofluorescence") as a means to indirectly quantify and spatially image the distribution of macular pigment (MP). The lipofuscin fluorescence intensity is reduced at all ret...Cytology; Sensitivity and Specificity2006-10
259 Saam, Brian; Laicher, GernotNuclear spin relaxation of 129Xe due to persistent xenon dimersWe have measured longitudinal nuclear relaxation rates of 129Xe in Xe-N2 mixtures at densities below 0.5 amagats in a magnetic field of 8.0 T. We find that intrinsic spin relaxation in this regime is principally due to fluctuations in the intramolecular spin-rotation (SR) and chemical-shift-anisot...Nuclear spin relaxation; Xe129; Xenon dimmers2006-12
260 Wu, Yong-ShiNumerical study of the three-dimensional random-field Ising model at zero and positive temperatureIn this paper the three-dimensional random-field Ising model is studied at both zero temperature and positive temperature. Critical exponents are extracted at zero temperature by finite size scaling analysis of large discontinuities in the bond energy. The heat capacity exponent α is found to be n...Bond energies; Ground states2006-08
261 Mishchenko, EugeneOptical conductivity of a two-dimensional electron liquid with spin-orbit interactionThe interplay of electron-electron interactions and spin-orbit coupling leads to a new contribution to the homogeneous optical conductivity of the electron liquid. The latter is known to be insensitive to many-body effects for a conventional electron system with parabolic dispersion. The parabolic...Optical conductivity; Electron liquid; Spin-orbit coupling2006-08
262 Furse, Cynthia M.Optimization of a buried microstrip antenna for simultaneous communication and sensing of soil moistureImbedded microstrip antennas have been previously demonstrated for use either as sensing elements or as components of a wireless communication system. This paper presents a method and dual use designs for simultaneous sensing of soil moisture and communication from the buried antenna to an external...Finite-difference time domain; FDTD; Automatic sprinkler control systems2006-03
263 Liu, FengOrigin of intergranular embrittlement of Al alloys induced by Na and Ca segregation: grain boundary weakeningUsing a first-principles computational tensile test, we show that the ideal tensile strength of an Al grain boundary (GB) is reduced with both Na and Ca GB segregation. We demonstrate that the fracture occurs in the GB interface, dominated by the break of the interfacial bonds. Experimentally, we f...Intergranular embrittlement; Grain boundary; Intergranular fracture2006-06
264 Mishchenko, Eugene; Raikh, Mikhail E.Penetration of external field into regular and random arrays of nanotubes: implications for field emissionWe develop an analytical theory of polarization of a vertically aligned array of carbon nanotubes (NTs) in external electric field. Such arrays are commonly utilized in field-emission devices, due to the known electrostatic effect of strong field enhancement near the tip of an individual NT. A sma...Field-emission current; Fowler-Nordheim law2006-06
265 Gondolo, PaoloPhase-space distribution of unbound dark matter near the sunWe resolve discrepancies in previous analyses of the flow of collisionless dark matter particles in the Sun's gravitational field. We determine the phase-space distribution of the flow both numerically, tracing particle trajectories back in time, and analytically, providing a simple correct relati...Phase-space distribution; Gravitational field; Velocity functions2006-10
266 Couldwell, William T.Photophobia in a blind patient: an alternate visual pathwayPhotophobia is a common neurological and ophthalmological symptom that has been associated with a growing number of neurosurgical conditions, especially compressive lesions. The exact signaling pathways and neurophysiological features of the disorder are not well understood; however, data from mult...2006-11
267 Vardeny, Zeev ValentinePhotophysics of excitons in quasi-one-dimensional organic semiconductors: single-walled carbon nanotubes and ∏-conjugated polymersThe nature of the primary photoexcitations in semiconducting single-walled carbon nanotubes (S-SWCNTs) is of strong current interest. We have studied the emission spectra of S-SWCNTs and two different rr-conjugated polymers in solutions and films, and have also performed ultrafast pump-probe spectro...Photophysics; Excitons; Quasi-one-dimensional; Single-walled carbon nanotubes; pi-conjugated polymers2006-02
268 Couldwell, William T.Pituitary apoplexy in the magnetic resonance imaging era: clinical significance of sphenoid sinus mucosal thickeningObject. The authors report their experience with pituitary apoplexy and evaluate the clinical significance of sphenoid sinus mucosal thickening found on magnetic resonance (MR) imaging. Methods. The cases of 28 patients (19 males and nine females) with pituitary apoplexy were reviewed retrospectiv...2006-06
269 Mishchenko, Eugene; Raikh, Mikhail E.Planar array of semiconducting nanotubes in an external electric field: collective screening and polarizabilityWe study theoretically the charge separation in a planar array of semiconducting nanotubes (NTs) of length, 2h, placed in an external electric field, F, parallel to their axes. By employing the conformal mapping, we find analytically the exact distribution of the induced charge density for the arb...Planar array2006-12
270 Mishchenko, EugenePolarized electric current in semiclassical transport with spin-orbit interactionSemiclassical solutions of two-dimensional Schrödinger equation with spin-orbit interaction and smooth potential are considered. In the leading order, spin polarization is in-plane and follows the evolution of the electron momentum for a given subband. Out-of-plane spin polarization appears as a ...Spin-polarized current; Sharvin conductance; Spin-orbit coupling2006-10
271 Harrison, Reid R.;Normann, Richard A.Preliminary study of thermal impact of a microelectrode array implanted in the brainOne requirement of a chronically implantable, wireless neural interface device is the integration of electronic circuitry with the microelectrode array. Since the electronic IC dissipates a certain amount of power, it will affect the temperature in the tissues surrounding the implant site. In this ...Microelectrode arrays; Neural recording; Utah Electrode Array; Thermal impact2006-08
272 Liu, FengPressure-induced transition in magnetoresistance of single-walled carbon nanotubesWe applied hydrostatic pressure (up to 10 GPa) to single-walled carbon nanotube bundles at low temperature (down to 2 K) to measure their magnetoresistance (MR) in a field up to 12 T. We found a pressure-induced transition in MR from positive to negative in the high-field regime. The onset of the tr...Single-walled carbon nanotubes; Pressure-induced2006-07
273 Liu, FengQuantum size effect on adatom surface diffusionUsing scanning tunneling microscopy, we demonstrate that the nucleation density of Fe islands on the surface of nanoscale Pb films oscillates with the film thickness, providing a direct manifestation of the quantum size effect on surface diffusion. The Fe adatom diffusion barriers were derived to be...Quantum size effect; QSE; Adatoms; Surface diffusion; Fe islands; Nanoscale metallic structures; Epitaxial growth; Pb films2006-12
274 Dawson, KyleRadiation tolerance of high-resistivity LBNL CCDsThick, 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 n-channel CCDs, including enhanced quantum efficiency and reduced fringing at near-infrared wavelengths, a smal...P-Channel CCDs; Astrophysics instrumentation; Space instrumentation; SNAP satellite; Space-based telescopes2006-10
275 Varner, Michael W.Risk of uterine rupture with a trial of labor in women with multiple and single prior cesarean delivery.OBJECTIVE: To determine whether the risk for uterine rupture is increased in women attempting vaginal birth after multiple cesarean deliveries. METHODS: We conducted a prospective multicenter observational study of women with prior cesarean delivery undergoing trial of labor and elective repeat oper...Cesarean Section, Repeat; Uterine Rupture; Vaginal Birth after Cesarean; Obstetric Labor Complications/surgery2006-07
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