1,402 research outputs found
A checklist of the Limnichidae and the Lutrochidae (Coleoptera) of the world
A checklist of the world species of Limnichidae (35 genera, 345 species) and Lutrochidae (1 genus, 11 species) is presented. The author, year of publication and page number, synonyms, distribution by country, and a terminal bibliography are given for each genus and species. Biological information is also reviewed
Rediscovery and redescription of Ceradryops punctatus Hinton, 1937 (Coleoptera: Dryopidae)
Ceradryops punctatus Hinton from Sri Lanka is redescribed and illustrated. Notes are made on the habitat of the species
Luchoelmis : a new genus of Elmidae (Coleoptera) from Chile and Argentina
Luchoelmis New Genus is described with four new species: aequalis, magallanensis, and penai from Chile and cekalovici from Argentina and Chile. Luchoelmis penai is designated as the type species of the genus. A key to the four species is presented
Three new species of Hexanchorus Sharp, 1882 (Coleoptera: Elmidae: Larainae) from South America
Three new species of Hexanchorus Sharp, H. dimorphus and H. shannoni from Argentina, and H. mcdiarmidi from Venezuela, are described and illustrated
Computer Simulation of Cytoskeleton-Induced Blebbing in Lipid Membranes
Blebs are balloon-shaped membrane protrusions that form during many
physiological processes. Using computer simulation of a particle-based model
for self-assembled lipid bilayers coupled to an elastic meshwork, we
investigated the phase behavior and kinetics of blebbing. We found that blebs
form for large values of the ratio between the areas of the bilayer and the
cytoskeleton. We also found that blebbing can be induced when the cytoskeleton
is subject to a localized ablation or a uniform compression. The results
obtained are qualitatively in agreement with the experimental evidence and the
model opens up the possibility to study the kinetics of bleb formation in
detail.Comment: To appear in Physical Review
Intra-Day Variability and the Interstellar Medium Towards 0917+624
The intra-day variable source 0917+624 displays annual changes in its
timescale of variability. This is explained in terms of a scintillation model
in which changes in the variability timescale are due to changes in the
relative velocity of the scintillation pattern as the Earth orbits the sun.
(see also astro-ph/0102050)Comment: 4 pages, 1 figure. Accepted for A&A Letter
Plasma Electronics
Contains reports on four research projects.United States ArmyUnited States NavyUnited States Air Force (Contract AF19(604)-7400)Lincoln Laboratory (Purchase Order DDL BB-107)National Science Foundation (Grant G-24073
Dissipative Dynamics of Collisionless Nonlinear Alfven Wave Trains
The nonlinear dynamics of collisionless Alfven trains, including resonant
particle effects is studied using the kinetic nonlinear Schroedinger (KNLS)
equation model. Numerical solutions of the KNLS reveal the dynamics of Alfven
waves to be sensitive to the sense of polarization as well as the angle of
propagation with respect to the ambient magnetic field. The combined effects of
both wave nonlinearity and Landau damping result in the evolutionary formation
of stationaryOA S- and arc-polarized directional and rotational
discontinuities. These waveforms are freqently observed in the interplanetary
plasma.Comment: REVTeX, 6 pages (including 5 figures). This and other papers may be
found at http://sdphpd.ucsd.edu/~medvedev/papers.htm
The spectra and energies of classical double radio lobes
We compare two temporal properties of classical double radio sources: i)
radiative lifetimes of synchrotron-emitting particles and ii) dynamical source
ages. We discuss how these can be quite discrepant from one another, rendering
use of the traditional spectral ageing method inappropriate: we contend that
spectral ages give meaningful estimates of dynamical ages only when these ages
are << 10^7 years. In juxtaposing the fleeting radiative lifetimes with source
ages which are significantly longer, a refinement of the paradigm for radio
source evolution is required. The changing spectra along lobes are explained,
not predominantly by synchrotron ageing but, by gentle gradients in a magnetic
field mediated by a low-gamma matrix which illuminates an energy-distribution
of particles, controlled largely by classical synchrotron loss in the high
magnetic field of the hotspot. The energy in the particles is an order of
magnitude higher than that inferred from the minimum-energy estimate, implying
that the jet-power is of the same order as the accretion luminosity produced by
the quasar central engine. This refined paradigm points to a resolution of the
findings of Rudnick et al (1994) and Katz-Stone & Rudnick (1994) that both the
Jaffe-Perola and Kardashev-Pacholczyk model spectra are invariably poor
descriptions of the curved spectral shape of lobe emission, and indeed that for
Cygnus A all regions of the lobes are characterised by a `universal spectrum'.
[abridged]Comment: LaTeX, 4 figures. To appear in A
Two-soliton solution for the derivative nonlinear Schr\"odinger equation with nonvanishing boundary conditions
An explicit two-soliton solution for the derivative nonlinear Schr\"odinger
equation with nonvanishing boundary conditions is derived, demonstrating
details of interactions between two bright solitons, two dark solitons, as well
as one bright soliton and one dark soliton. Shifts of soliton positions due to
collisions are analytically obtained, which are irrespective of the bright or
dark characters of the participating solitons.Comment: 11 pages, 4 figures. Phys. Lett. A 2006 (in press
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