34,507 research outputs found
Publications of the exobiology program for 1984: A special bibliography
A bibliography of NASA exobiology programs is given. Planetary environments; chemical evolution; organic geochemistry; extraterrestrial intelligence; and the effect of planetary solar and astrophysical phenomena on the evolution of complex life in the universe are among the topics listed
Observation of Single Transits in Supercooled Monatomic Liquids
A transit is the motion of a system from one many-particle potential energy
valley to another. We report the observation of transits in molecular dynamics
(MD) calculations of supercooled liquid argon and sodium. Each transit is a
correlated simultaneous shift in the equilibrium positions of a small local
group of particles, as revealed in the fluctuating graphs of the particle
coordinates versus time. This is the first reported direct observation of
transit motion in a monatomic liquid in thermal equilibrium. We found transits
involving 2 to 11 particles, having mean shift in equilibrium position on the
order of 0.4 R_1 in argon and 0.25 R_1 in sodium, where R_1 is the nearest
neighbor distance. The time it takes for a transit to occur is approximately
one mean vibrational period, confirming that transits are fast.Comment: 19 pages, 8 figure
Conceptualizing Student Practice for the 21st Century: Educational and Ethical Considerations in Modernizing the District of Columbia Student Practice Rules
This article traces the history of the amendment process. It provides a short history of student practice rules and then, using the student practice rule in effect in the District of Columbia prior to the 2014 amendments, describes the various components of those rules that courts and bars across the nation have implemented to assist courts, advance legal education, and preserve advocates’ ethical obligations to clients. It then describes some of the comments to the proposed amendments offered by the District of Columbia Bar and other D.C. lawyers during the public comment period and the modifications to the District of Columbia student practice rule that the District of Columbia Court of Appeals accepted. Finally, it discusses some areas of disagreement that arose during the process and a description of the reasons for those disagreements
Low-energy interaction of composite spin-half systems with scalar and vector fields
We consider a composite spin-half particle moving in spatially-varying scalar
and vector fields. The vector field is assumed to couple to a conserved charge,
but no assumption is made about either the structure of the composite or its
coupling to the scalar field. A general form for the piece of the spin-orbit
interaction of the composite with the scalar and vector fields which is
first-order in momentum transfer and second-order in the fields is
derived.Comment: 10 pages, RevTe
A covariant gauge-invariant three-dimensional description of relativistic bound-states
A formalism is presented which allows covariant three-dimensional bound-state
equations to be derived systematically from four-dimensional ones without the
use of delta-functions. The amplitude for the interaction of a bound state
described by these equations with an electromagnetic probe is constructed. This
amplitude is shown to be gauge invariant if the formalism is truncated at the
same coupling-constant order in both the interaction kernel of the integral
equation and the electromagnetic current operator.Comment: 17 pages, RevTeX, uses BoxedEPS.te
A summary of the test procedures and operational details of an ocean dumping pollution monitoring experiment conducted 7 October 1976
A remote sensor experiment was conducted at a sewage sludge dump site off the Delaware/Maryland coast. Two aircraft serving as remote sensor platforms flew over the dump site during a sludge dump. One aircraft carried a multispectral scanner and the other aircraft carried a rapid scanning spectrometer. Data from sea-truth stations were collected concurrent with overpasses of the aircraft. All sensors were operational and produced good digital data
Raised cortisol excretion rate in urine and contamination by topical steroids
No abstract available
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