9,713 research outputs found
Taxonomy and Natural History of Nyctiphrynus rosenbergi (Caprimulgidae)
This is the published version. Copyright Central Ornithology Publication Offic
Holography and Cosmological Singularities
Certain null singularities in ten dimensional supergravity have natural
holographic duals in terms of Matrix Theory and generalizations of the AdS/CFT
correspondence. In many situations the holographic duals appear to be well
defined in regions where the supergravity develops singularities. We describe
some recent progress in this area.Comment: Anomaly equation corrected. References adde
First Description of the Nest and Eggs of the Moss-Backed Tanager (Buthraupis [Bangsia] Edwardsi)
This is the published version. Copyright Central Ornithology Publication Offic
Strain Hardening in Polymer Glasses: Limitations of Network Models
Simulations are used to examine the microscopic origins of strain hardening
in polymer glasses. While traditional entropic network models can be fit to the
total stress, their underlying assumptions are inconsistent with simulation
results. There is a substantial energetic contribution to the stress that rises
rapidly as segments between entanglements are pulled taut. The thermal
component of stress is less sensitive to entanglements, mostly irreversible,
and directly related to the rate of local plastic arrangements. Entangled and
unentangled chains show the same strain hardening when plotted against the
microscopic chain orientation rather than the macroscopic strain.Comment: 4 pages, 3 figure
An Overview of the Northern Gulf of Mexico Ecosystem
The Gulf of Mexico is a large marine ecosystem (LME) bordered by the southern United States, Mexico, and Cuba. This general overview of its northern portion covers physiography, significant oceanographic features, the influence of major rivers and freshwater, biological productivity, and food web characteristics. It then describes the pelagic and benthic components of the major habitats: oceanic (continental slope and abyssal plain), continental shelf and bays, estuaries, and marshes, with descriptions of prominent processes and some dominant organisms. For each habitat several species from a variety of trophic levels are introduced and their general role in the ecosystem discussed. In 2010 the northern portion of the Gulf was the site of the largest U.S. marine oil spill in history and is now the focus of an unprecedented restoration effort. Successful restoration of the northern Gulf will depend on an integrated view of this LME and the forces that maintain and change it. This introduction to the northern Gulf marine ecosystem should be useful for policy makers, informing decisions on proposed restoration actions
Geometric phases and anholonomy for a class of chaotic classical systems
Berry's phase may be viewed as arising from the parallel transport of a
quantal state around a loop in parameter space. In this Letter, the classical
limit of this transport is obtained for a particular class of chaotic systems.
It is shown that this ``classical parallel transport'' is anholonomic ---
transport around a closed curve in parameter space does not bring a point in
phase space back to itself --- and is intimately related to the Robbins-Berry
classical two-form.Comment: Revtex, 11 pages, no figures
Voice, plumage and natural history of Anthony's Nightjar (Caprimulgus anthonyi)
This is the published version. Copyright Central Ornithology Publication Offic
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