3,967 research outputs found
Quantitative uniqueness for elliptic equations with singular lower order terms
We use a Carleman type inequality of Koch and Tataru to obtain quantitative
estimates of unique continuation for solutions of second order elliptic
equations with singular lower order terms. First we prove a three sphere
inequality and then describe two methods of propagation of smallness from sets
of positive measure.Comment: 23 pages, v2 small changes are done and some mistakes are correcte
Contributors to the June Issue/Notes
Notes by David S. Landis, Thomas F. Bremer, John F. Power, L. E. Merman, Francis J. Paulson, Arthur M. Diamond, Harold Berliner, Robert A. Oberfell, Eugene Charles Wohlhorn, and Roger D. Gustafson
Contributors to the June Issue/Notes
Notes by David S. Landis, Thomas F. Bremer, John F. Power, L. E. Merman, Francis J. Paulson, Arthur M. Diamond, Harold Berliner, Robert A. Oberfell, Eugene Charles Wohlhorn, and Roger D. Gustafson
Ciliary neurotrophic factor coordinately activates transcription of neuropeptide genes in a neuroblastoma cell line.
The Volume of a Local Nodal Domain
Let M either be a closed real analytic Riemannian manifold or a closed smooth
Riemannian surface. We estimate from below the volume of a nodal domain
component in an arbitrary ball provided that this component enters the ball
deeply enough.Comment: 21 pages; introduction improved putting the problem in a larger
context
Three-dimensional structural interrelations between cells, extracellular matrix and mineral in normally mineralizing Aavian leg tendon
The spatial-temporal relationship between cells, extracellular matrices, and mineral deposits is fundamental for an improved understanding of mineralization mechanisms in vertebrate tissues. By utilizing focused ion beam-scanning electron microscopy with serial surface imaging, normally mineralizing avian tendons have been studied with nanometer resolution in three dimensions with volumes exceeding tens of micrometers in range. These parameters are necessary to yield sufficiently fine ultrastructural details while providing a comprehensive overview of the interrelationships between the tissue structural constituents. Investigation reveals a complex lacuno-canalicular network in highly mineralized tendon regions, where ∼100 nm diameter canaliculi emanating from cell (tenocyte) lacunae surround extracellular collagen fibril bundles. Canaliculi are linked to smaller channels of ∼40 nm diameter, occupying spaces between fibrils. Close to the tendon mineralization front, calcium-rich deposits appear between the fibrils and, with time, mineral propagates along and within them. These close associations between tenocytes, tenocyte lacunae, canaliculi, small channels, collagen, and mineral suggest a concept for the mineralization process, where ions and/or mineral precursors may be transported through spaces between fibrils before they crystallize along the surface of and within the fibrils
Natural Wormholes as Gravitational Lenses
Visser has suggested traversable 3-dimensional wormholes that could plausibly
form naturally during Big Bang inflation. A wormhole mouth embedded in high
mass density might accrete mass, giving the other mouth a net *negative* mass
of unusual gravitational properties. The lensing of such a gravitationally
negative anomalous compact halo object (GNACHO) will enhance background stars
with a time profile that is observable and qualitatively different from that
recently observed for massive compact halo objects (MACHOs) of positive mass.
We recommend that MACHO search data be analyzed for GNACHOs.Comment: 4 pages; plus 4 figures; ReV_TeX 3.0; DOE/ER/40537-001/NPL94-07-01
Large-Mass Ultra-Low Noise Germanium Detectors: Performance and Applications in Neutrino and Astroparticle Physics
A new type of radiation detector, a p-type modified electrode germanium
diode, is presented. The prototype displays, for the first time, a combination
of features (mass, energy threshold and background expectation) required for a
measurement of coherent neutrino-nucleus scattering in a nuclear reactor
experiment. The device hybridizes the mass and energy resolution of a
conventional HPGe coaxial gamma spectrometer with the low electronic noise and
threshold of a small x-ray semiconductor detector, also displaying an intrinsic
ability to distinguish multiple from single-site particle interactions. The
present performance of the prototype and possible further improvements are
discussed, as well as other applications for this new type of device in
neutrino and astroparticle physics (double-beta decay, neutrino magnetic moment
and WIMP searches).Comment: submitted to Phys. Rev.
Al0.52In0.48P 55Fe x-ray-photovoltaic battery
An Al0.52In0.48P 55Fe radioisotope microbattery is demonstrated over the temperature range −20 °C to 160 °C. Al0.52In0.48P p+-i-n+ mesa structures were used to collect the photons from a 238 MBq 55Fe radioisotope x-ray source. The effects of temperature on the key microbattery parameters were studied. Increasing the temperature, the saturation current increased; whilst the open circuit voltage, the maximum power and the conversion efficiency decreased. An open circuit voltage of 0.97V and a conversion efficiency of 22% were measured in a single p+-i-n+ mesa structure at −20 °C. The highest total microbattery maximum output power using two mesa structures was 1.2 pW at −20 °C
Glecaprevir and Pibrentasvir for 12 Weeks for Hepatitis C Virus Genotype 1 Infection and Prior Direct-Acting Antiviral Treatment
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