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Nonlinear Intersubband Photoabsorption in Asymmetric Single Quantum Wells
(American Institute of Physics, 2005)
A density-matrix approach combined with time-dependent density-functional theory is used to calculate the intersubband photoabsorption in a strongly driven, DC-biased GaAs/AlGaAs single quantum well. For certain frequencies ...
Non- V -representability of currents in time-dependent many-particle systems
(American Physical Society, 2005)
We argue that an arbitrarily chosen time-dependent current density is generically non-V-representable in a many-particle system; i.e., it cannot be obtained by applying only a time-dependent scalar potential to the system. ...
Temperature Dependence of the Tunneling Amplitude between Quantum Hall Edges
(American Physical Society, 2005)
Recent experiments have studied the tunneling current between the edges of a fractional quantum Hall liquid as a function of temperature and voltage. The results of the experiment are puzzling because at “high” temperature ...
Observing the spin Coulomb drag in spin-valve devices
(American Physical Society, 2005)
The Coulomb interaction between electrons of opposite spin orientations in a metal or in a doped semiconductor results in a negative off-diagonal component of the electrical resistivity matrix—the so-called “spin-drag ...
Heterostructure unipolar spin transistors
(American Institute of Physics, 2005)
We extend the analogy between charge-based bipolar semiconductor electronics and spin-based unipolar electronics by considering unipolar spin transistors with different equilibrium spin splittings in the emitter, base, and ...
Erratum: Dynamical exchange-correlation potentials for an electron liquid [Phys. Rev. B 65, 235121 (2002)]
(American Physical Society, 2005)
Erratum concerning Dynamical exchange-correlation potentials for an electron liquid [Phys. Rev. B 65, 235121 (2002)]
Integration of NOS Instruction into a Physical Science Content Course for Elementary Teachers: Enhancing Efforts of Teacher Education Programs?
(2005)
This study investigated the effectiveness of integrating explicit-and-reflective NOS instruction into a physics course for pre-service elementary teachers. Reflective discussions, student scenarios, and content-generic NOS ...
The Effect of Stellar Evolution on SiC Dust Grain Sizes
(American Astronomical Society, 2005)
Stars on the asymptotic giant branch (AGB) produce dust in their circumstellar shells. The nature of the dust-forming environment is influenced by the evolution of the stars, in terms of both chemistry and density, leading ...
The Multitude of Molecular Hydrogen Knots in the Helix Nebula
(Institute of Physics, 2005)
We present Hubble Space Telescope NICMOS imaging of the H2 2.12 μm emission in five fields in the Helix Nebula ranging in radial distance from 250'' to 450'' from the central star. The images reveal arcuate structures with ...
The Nature and Origin of Molecular Knots in Planetary Nebulae
(American Institute of Physics, 2005)
Planetary Nebulae (PNe) are major contributors to the enrichment of the interstellar medium (ISM). Knots and filaments in the ionized gas images of PNe are common, if not ubiquitous. Additionally, it has been shown that ...
Decrease in Anogenital Distance among Male Infants with Prenatal Phthalate Exposure
(Environmental Health Perspectives, 2005-05)
Prenatal phthalate exposure impairs testicular function and shortens anogenital distance (AGD) in male rodents. We present data from the first study to examine AGD and other genital measurements in relation to prenatal ...
Transillumination Optical Tomography of Tissue-Engineered Blood Vessels: A Monte Carlo Simulation
(The Optical Society of America, 2005-07)
A Monte Carlo technique has been developed to simulate the transillumination laser computed tomography of tissue-engineered blood vessels. The blood vessel was modeled as a single cylinder layer mounted on a tubular mandrel. ...
Imaging Obscured Subsurface Inhomogeneity Using Laser Speckle
(The Optical Society of America, 2005-12)
We have developed a laser speckle imaging method to reveal obscured subsurface inhomogeneities that cannot be seen under incoherent illumination. Speckle images of a scattering object were generated under
coherent ...
For a Sustainable Agriculture, We Need More Adam Smith, Not Less
(2005-06)
There are two competing approaches to sustainability in agriculture. One stresses a strict economic approach in which market forces should be allowed to guide the activities of agricultural producers. The other advocates ...
Lowpass Filtering of Rate-Distortion Functions for Quality Smoothing in Real-Time Video Communication
(IEEE, 2005)
In variable-bit-rate (VBR) video coding, the video is pre-processed to collect sequence-level statistics, which are used
for global bit allocation in the actual encoding stage to obtain a smoothed video presentation ...
Accurate 3D Tracking of Rigid Objects with Occlusion Using Active Appearance Models
(IEEE, 2005)
In this paper we present a new method for tracking rigid objects using a modified version of the Active Appearance Model. Unlike most of the other appearance-based methods
in the literature, such as [3,5,6,9,11], our ...
Influence of subunit structure on the oligomerization state of light harvesting complexes: a free energy calculation study
(arXiv, 2005)
Light harvesting complexes 2 (LH2) from Rhodospirillum (Rs.) molischianum and Rhodopseudomonas (Rps.) acidophila form ring complexes out of eight or nine identical subunits, respectively. Here, we investigate computationally ...
Trust in Scientists and Food Manufacturers, with Implications for the Public Support of Biotechnology
(2005-07)
The purpose of this paper is to determine what factor affect trust in scientists and food manufacturers, and to examine how trust in these institutions affects public support for biotechnology. Data from the U.S. Biotechnology ...
Mosaics Magazine, 2005 Winter
(University of Missouri--Columbia, College of Arts and Science, 2005)
Magazine of the College of Arts and Science. Subjects include Take Action, Adventures in Archaeometry, The Superman of Pop Culture, Nerds in Training, This Sun Shines in Statistics, Heartbreaking Work with Heartwarming ...
Expression of Target Optical Properties in Subsurface Polarization-gated Imaging
(The Optical Society of America, 2005-05)
We examined the expression of target optical properties in subsurface polarization imaging under linearly and circularly polarized illumination. Reflecting, scattering, and absorption targets were imaged in tissue mimic ...