17,209 research outputs found
AdS Solutions of 2D Type 0A
We present a two-parameter family of AdS solutions to the two-dimensional
type 0A effective action.Comment: 9 page
Is the Internet a Viable Threat to Representative Democracy?
The Internet, despite its relatively recent advent, is critical to millions of Americans’ way of life. Although the Internet arguably opens new opportunities for citizens to become more directly involved in their government, some scholars fear this direct involvement poses a risk to one of the Constitution’s most precious ideals: representative democracy. This iBrief explores whether the constitutional notion of representation is vulnerable to the Internet’s capacity to open new vistas for a more direct democracy by analyzing statistics and theories about why voters in the United States do or do not vote and by examining the inherent qualities of the Internet itself. This iBrief concludes that the Constitution will adapt to the Internet and the Internet to the Constitution, such that even if there are advances in direct democracy, representative democracy will not be unduly threatened
Keck Deep Fields. I. Observations, Reductions, and the Selection of Faint Star-Forming Galaxies at Redshifts z~4, 3, and 2
We introduce a very deep, R_lim~27, multicolor imaging survey of very faint
star-forming galaxies at z~4, z~3, z~2.2, and z~1.7. This survey, carried out
on the Keck I telescope, uses the very same UGRI filter system that is employed
by the Steidel team to select galaxies at these redshifts, and thus allows us
to construct identically-selected, but much fainter, samples. However, our
survey reaches ~1.5 mag deeper than the work of Steidel and his group, letting
us probe substantially below the characteristic luminosity L* and thus study
the properties and redshift evolution of the faint component of the high-z
galaxy population. The survey covers 169 square arcminutes in three spatially
independent patches on the sky and -- to R<~27 -- contains 427 GRI-selected z~4
LBGs, 1481 UGR-selected z~3 LBGs, 2417 UGR-selected z~2.2 star-forming
galaxies, and 2043 UGR-selected z~1.7 star-forming galaxies. In this paper, the
first in a series, we introduce the survey, describe our observing and data
reduction strategies, and outline the selection of our z~4, z~3, z~2.2, and
z~1.7 samples.Comment: To appear in Ap
Cougar Dispersal and Natal Homing in a Desert Environment
We present a review of cougar dispersal literature and the first evidence of natural (i.e., unmanipulated) homing behavior by a dispersing male cougar (Puma concolor) that sustained severe injuries crossing the northern Mojave Desert. Based on Global Positioning System and ground tracking data, the male traveled a total distance of 981.1 km at 5.03 km/d, including 170.31 km from the Desert National Wildlife Refuge to the northwestern Grand Canyon, where he sustained severe injuries. The interkill interval increased from 7.1 ± 2.7 d while he was in his natal range to 17.5 ± 4.9 d during dispersal. While homing, the male appeared to consume only reptiles until he died, 33.7 km from his capture site. In desert environments where prey availability is low, homing behavior may be an important strategy for dispersing cougars, providing a mechanism for persistence when the best quality habitats they encounter are already occupied by adult residents. Therefore, managing for habitat connectivity can ensure successful homing as well as dispersal on a greater scale than has been previously suggested. Elucidating the mechanisms that trigger homing during dispersal may provide critical insight into animal movements often overlooked as mundane behavior
SGR 1806-20 Is a Set of Independent Relaxation Systems
The Soft Gamma Repeater 1806-20 produced patterns of bursts during its 1983
outburst that indicate multiple independent energy accumulation sites, each
driven by a continuous power source, with sudden, incomplete releases of the
accumulated energy. The strengths of the power sources and their durations of
activity vary over several orders of magnitude.Comment: Accepted ApJLett, 15 pages, 3 figure
USAF Aircraft Maintenance Officer Knowledge, Skills and Abilities and Commonalities among the Logistics Officer Corps
This study investigated options to improve 21A training and education by first validating the Air Force\u27s logistics mission sets as Deployment, Distribution, Supply Management, Repair Network Integration, Mission Generation, Lifecycle Logistics and Joint Logistics. Then, the Knowledge, Skills, and Abilities (KSAs) considered important to execute each mission set were gathered from a representative sample of Air Force Logistics Officers via field interviews and focus groups. An analysis of results categorizes probable needs (high, medium, low) of KSAs for each mission set and assesses how well they are currently taught, if at all. Additionally, lists of KSAs that overlap multiple mission sets were created along with process options for integrating them into training and education. Based on a discussion of the synergistic effects on acquiring these KSAs, it is also recommended that the Logistics Readiness Squadron be realigned under a common group at the operational wing with the rest of the Logistics Units (presently the Maintenance Group). Finally, a career tracking model is proposed to deliberately build experts in strategic 21A career paths, which this study identifies as Career Maintenance Officers, Air Force Materiel Managers and Joint Logistics Officers
Diagnosing magnetars with transient cooling
Transient X-ray emission, with an approximate t^{-0.7} decay, was observed
from SGR 1900+14 over 40 days following the the giant flare of 27 Aug 1998. We
calculate in detail the diffusion of heat to the surface of a neutron star
through an intense 10^{14}-10^{15} G magnetic field, following the release of
magnetic energy in its outer layers. We show that the power law index, the
fraction of burst energy in the afterglow, and the return to persistent
emission can all be understood if the star is composed of normal baryonic
material.Comment: 9 pages, 1 eps figur
Coherent Emission from Magnetars
It is proposed that magnetospheric currents above the surfaces of magnetars
radiate coherent emission in analogy to pulsars. Scaling the magnetospheric
parameters suggests that the coherent emission from magnetars would emerge in
the infra-red or optical
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