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Reports and Maps of the Geological Survey Released Only in the Open Files, 1966
There is a reference to the Espey "Some effects on urbanization on storm runoff, Waller Creek".Waller Creek Working Grou
Outer planet probe engineering model structural tests
A series of proof of concept structural tests was performed on an engineering model of the Outer Planets Atmospheric Entry Probe. The tests consisted of pyrotechnic shock, dynamic and static loadings. The tests partially verified the structural concept
Probing strongly interacting atomic gases with energetic atoms
We investigate properties of an energetic atom propagating through strongly
interacting atomic gases. The operator product expansion is used to
systematically compute a quasiparticle energy and its scattering rate both in a
spin-1/2 Fermi gas and in a spinless Bose gas. Reasonable agreement with recent
quantum Monte Carlo simulations even at a relatively small momentum k/kF>1.5
indicates that our large-momentum expansions are valid in a wide range of
momentum. We also study a differential scattering rate when a probe atom is
shot into atomic gases. Because the number density and current density of the
target atomic gas contribute to the forward scattering only, its contact
density (measure of short-range pair correlation) gives the leading
contribution to the backward scattering. Therefore, such an experiment can be
used to measure the contact density and thus provides a new local probe of
strongly interacting atomic gases.Comment: 35 pages, 11 figures; (v4) published with the new titl
Planets in triple star systems--the case of HD188753
We consider the formation of the recently discovered ``hot Jupiter'' planet
orbiting the primary component of the triple star system HD188753. Although the
current outer orbit of the triple is too tight for a Jupiter-like planet to
have formed and migrated to its current location, the binary may have been much
wider in the past. We assume here that the planetary system formed in an open
star cluster, the dynamical evolution of which subsequently led to changes in
the system's orbital parameters and binary configuration. We calculate cross
sections for various scenarios that could have led to the multiple system
currently observed, and conclude that component A of HD188753 with its planet
were most likely formed in isolation to be swapped in a triple star system by a
dynamical encounter in an open star cluster. We estimate that within 500pc of
the Sun there are about 1200 planetary systems which, like Hd188753, have
orbital parameters unfavorable for forming planets but still having a planet,
making it quite possible that the HD188753 system was indeed formed by a
dynamical encounter in an open star cluster.Comment: ApJ Letters in pres
Systematic review of the current status of cadaveric simulation for surgical training
Background:
There is growing interest in and provision of cadaveric simulation courses for surgical trainees. This is being driven by the need to modernize and improve the efficiency of surgical training within the current challenging training climate. The objective of this systematic review is to describe and evaluate the evidence for cadaveric simulation in postgraduate surgical training.
Methods:
A PRISMA‐compliant systematic literature review of studies that prospectively evaluated a cadaveric simulation training intervention for surgical trainees was undertaken. All relevant databases and trial registries were searched to January 2019. Methodological rigour was assessed using the widely validated Medical Education Research Quality Index (MERSQI) tool.
Results:
A total of 51 studies were included, involving 2002 surgical trainees across 69 cadaveric training interventions. Of these, 22 assessed the impact of the cadaveric training intervention using only subjective measures, five measured impact by change in learner knowledge, and 23 used objective tools to assess change in learner behaviour after training. Only one study assessed patient outcome and demonstrated transfer of skill from the simulated environment to the workplace. Of the included studies, 67 per cent had weak methodology (MERSQI score less than 10·7).
Conclusion:
There is an abundance of relatively low‐quality evidence showing that cadaveric simulation induces short‐term skill acquisition as measured by objective means. There is currently a lack of evidence of skill retention, and of transfer of skills following training into the live operating theatre
Statistical quality control applied to a telemetry system acceptance prodedure Technical report no. 13
Statistical quality control applied to telemetry system acceptance procedur
Surface Contribution to Raman Scattering from Layered Superconductors
Generalizing recent work, the Raman scattering intensity from a semi-infinite
superconducting superlattice is calculated taking into account the surface
contribution to the density response functions. Our work makes use of the
formalism of Jain and Allen developed for normal superlattices. The surface
contributions are shown to strongly modify the bulk contribution to the
Raman-spectrum line shape below , and also may give rise to additional
surface plasmon modes above . The interplay between the bulk and
surface contribution is strongly dependent on the momentum transfer
parallel to layers. However, we argue that the scattering
cross-section for the out-of-phase phase modes (which arise from interlayer
Cooper pair tunneling) will not be affected and thus should be the only
structure exhibited in the Raman spectrum below for relatively large
. The intensity is small but perhaps observable.Comment: 14 pages, RevTex, 6 figure
Thermalization of magnons in yttrium-iron garnet: nonequilibrium functional renormalization group approach
Using a nonequilibrium functional renormalization group (FRG) approach we
calculate the time evolution of the momentum distribution of a magnon gas in
contact with a thermal phonon bath. As a cutoff for the FRG procedure we use a
hybridization parameter {\Lambda} giving rise to an artificial damping of the
phonons. Within our truncation of the FRG flow equations the time evolution of
the magnon distribution is obtained from a rate equation involving
cutoff-dependent nonequilibrium self-energies, which in turn satisfy FRG flow
equations depending on cutoff-dependent transition rates. Our approach goes
beyond the Born collision approximation and takes the feedback of the magnons
on the phonons into account. We use our method to calculate the thermalization
of a quasi two-dimensional magnon gas in the magnetic insulator yttrium-iron
garnet after a highly excited initial state has been generated by an external
microwave field. We obtain good agreement with recent experiments.Comment: 16 pages, 6 figures, final versio
Two-fluid dynamics for a Bose-Einstein condensate out of local equilibrium with the non-condensate
We extend our recent work on the two-fluid hydrodynamics of a Bose-condensed
gas by including collisions involving both condensate and non-condensate atoms.
These collisions are essential for establishing a state of local thermodynamic
equilibrium between the condensate and non-condensate. Our theory is more
general than the usual Landau two-fluid theory, to which it reduces in the
appropriate limit, in that it allows one to describe situations in which a
state of complete local equilibrium between the two components has not been
reached. The exchange of atoms between the condensate and non-condensate is
associated with a new relaxational mode of the gas.Comment: 4 pages, revtex, 1 postscript figure, Fig.1 has been correcte
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