673 research outputs found
Literacy, Poverty, and Brain Development: Toward a New, Place-Based Educational Intervention
This paper provides an overview of emerging research focused on how living in an area of concentrated poverty can impact brain development and explores some possible applications of this research to education policy. One of the key findings is that state and federal policy-makers may need to adopt programs that integrate educational policy with housing and planning policy in order to protect and fulfill each child\u27s educational rights. In order to impress upon readers the scale of the nation\u27s current educational failures and the need for a significant change in policy, this paper first addresses adult illiteracy in the United States. After defining functional illiteracy according to metrics derived from the National Adult Literacy Survey, this paper then explores the various ways in which high rates of functional illiteracy negatively impact our society. The negative effects of living in an area of concentrated poverty, which correlates with functional illiteracy, and the difficulty inherent in escaping such areas of concentrated poverty are also briefly examined. The paper then proceeds to discuss the evolution of educational rights, and how federal and state courts have interpreted state obligations to provide a fair, equal, and meaningful opportunity to a sound basic education. The paper also examines the effectiveness of various remedies instituted as a result of successful education litigation. This discussion aims to establish not only the existence of educational rights, but also the inadequacy of previous efforts to implement and enforce such rights. The key problem identified in the paper is that previous approaches to effectuate educational rights, including court-ordered remedies, have failed to account for circumstantial factors relating to the socio-economic conditions within particular school districts. Finally, the paper provides an overview of emerging neuroscience research related to cognitive development and socioeconomic status, which illustrates how the circumstances in which a child is raised can significantly inhibit that child\u27s educational opportunities. While the field of neuroscience has only just begun to investigate the effects of socioeconomic status, including both family and community wealth, on brain development and function, preliminary studies indicate a correlation between socioeconomic status and some aspects of brain development which may have an impact on student performance in typical school settings
Superradiant Decay of Cyclotron Resonance of Two-Dimensional Electron Gases
We report on the observation of collective radiative decay, or superradiance,
of cyclotron resonance (CR) in high-mobility two-dimensional electron gases in
GaAs quantum wells using time-domain terahertz magnetospectroscopy. The decay
rate of coherent CR oscillations increases linearly with the electron density
in a wide range, which is a hallmark of superradiant damping. Our fully quantum
mechanical theory provides a universal formula for the decay rate, which
reproduces our experimental data without any adjustable parameter. These
results firmly establish the many-body nature of CR decoherence in this system,
despite the fact that the CR frequency is immune to electron-electron
interactions due to Kohn's theorem.Comment: 5 pages, 4 figure
Cape Sable Seaside Sparrow Habitat Monitoring and Assessment - 2010 Final Report
For the last two decades, the Cape Sable seaside sparrow (CSSS), a federally endangered species, has been a pivot point for water management operations in the Everglades, primarily because a decline in sparrow population in the early 1990s was attributed in part to managementinduced alterations in hydrologic regimes. With a goal of understanding the response of landscape-level processes to hydrological restoration and its interaction with fire, a study intended to monitor vegetation structure and composition throughout the marl prairie landscape has been conducted since 2003 with funding from U.S. Army Corps of Engineers (USACE). In the first three years (2003-2005), vegetation structure and composition was characterized in relation to the existing hydrologic regime and fire history. During 2006-2010, vegetation was resampled to assess vegetation change within the sparrow habitat. This document summarizes the vegetation change pattern observed between the two sampling periods in sub-population A, C, E and F, emphasizing the work accomplished in FY 2010
The XMM Cluster Survey: The Dynamical State of XMMXCS J2215.9-1738 at z=1.457
We present new spectroscopic observations of the most distant X-ray selected
galaxy cluster currently known, XMMXCS J2215.9-1738 at z=1.457, obtained with
the DEIMOS instrument at the W. M. Keck Observatory, and the FORS2 instrument
on the ESO Very Large Telescope. Within the cluster virial radius, as estimated
from the cluster X-ray properties, we increase the number of known
spectroscopic cluster members to 17 objects, and calculate the line of sight
velocity dispersion of the cluster to be 580+/-140 km/s. We find mild evidence
that the velocity distribution of galaxies within the virial radius deviates
from a single Gaussian. We show that the properties of J2215.9-1738 are
inconsistent with self-similar evolution of local X-ray scaling relations,
finding that the cluster is underluminous given its X-ray temperature, and that
the intracluster medium contains ~2-3 times the kinetic energy per unit mass of
the cluster galaxies. These results can perhaps be explained if the cluster is
observed in the aftermath of an off-axis merger. Alternatively, heating of the
intracluster medium through supernovae and/or Active Galactic Nuclei activity,
as is required to explain the observed slope of the local X-ray
luminosity-temperature relation, may be responsible.Comment: 13 pages, 6 figures, accepted for publication in Ap
The XMM Cluster Survey: a massive galaxy cluster at z = 1.45
We report the discovery of XMMXCS J2215.9-1738, a massive galaxy cluster at z=1.45, which was found in the XMM Cluster Survey. The cluster candidate was initially identified as an extended X-ray source in archival XMM data. Optical spectroscopy shows that six galaxies within a ~60" diameter region lie at z=1.45+/-0.01. Model fits to the X-ray spectra of the extended emission yield kT=7.4+2.7-1.8 keV (90% confidence); if there is an undetected central X-ray point source, then kT=6.5+2.6-1.8 keV. The bolometric X-ray luminosity is LX=4.4+0.8-0.6C 1044 ergs s-1 over a 2 Mpc radial region. The measured TX, which is the highest for any known cluster at z>1, suggests that this cluster is relatively massive for such a high redshift. The redshift of XMMXCS J2215.9-1738 is the highest currently known for a spectroscopically confirmed cluster of galaxies
Spacecraft materials studies on the Aerospace Corporation tray on EOIM-3
A passive tray was flown on the Effects of Oxygen Interaction with Materials experiment on STS-46 (EOIM-3) with 82 samples from The Aerospace Corporation. A variety of advanced materials related to potential uses on future spacecraft were included for evaluation representing optical coatings, lubricants, polymers, composites, carbon-carbon composite protective coatings, graphite protective coatings, thermal-control materials, and some samples of current materials. An overview of the available results from the investigations of these materials is presented
Photon-noise limited sensitivity in titanium nitride kinetic inductance detectors
We demonstrate photon-noise limited performance at sub-millimeter wavelengths
in feedhorn-coupled, microwave kinetic inductance detectors (MKIDs) made of a
TiN/Ti/TiN trilayer superconducting film, tuned to have a transition
temperature of 1.4~K. Micro-machining of the silicon-on-insulator wafer
backside creates a quarter-wavelength backshort optimized for efficient
coupling at 250~\micron. Using frequency read out and when viewing a variable
temperature blackbody source, we measure device noise consistent with photon
noise when the incident optical power is ~0.5~pW, corresponding to noise
equivalent powers ~3 W/. This
sensitivity makes these devices suitable for broadband photometric applications
at these wavelengths
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