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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 ...
Functional Imaging Using InGaAs/GaAs Photorefractive Multiple Quantum Wells
(American Institute of Physics, 2005)
We propose the use of an InGaAs/GaAs photorefractive quantum well (PRQW) as an adaptive beam combiner for holographic optical coherence imaging applications. Holograms have been observed by using a diode laser and an ...
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 ...
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 ...
Pressure Raman effects and internal stress in network glasses
(American Physical Society, 2005)
Raman scattering from binary GexSe1−x glasses under hydrostatic pressure shows onset of a steady increase in the frequency of modes of corner-sharing GeSe4 tetrahedral units when the external pressure P exceeds a threshold ...
Lifetime of a quasiparticle in an electron liquid
(American Physical Society, 2005)
We calculate the inelastic lifetime of an electron quasiparticle due to Coulomb interactions in an electron liquid at low (or zero) temperature in two and three spatial dimensions. The contribution of “exchange” processes ...
Note on the relationship between the speed of light and gravity in the bi-metric theory of gravity
(arXiv, 2005)
Relationship between the speed of gravity c_g and the speed of light c_e in the bi-metric theory of gravity is discussed. We reveal that the speed of light is a function of the speed of gravity which is a primary fundamental ...
Shapiro Effect as a Possible Cause of the Low-Frequency Pulsar Timing Noise in Globular Clusters
(arXiv, 2005)
A prolonged timing of millisecond pulsars has revealed low-frequency uncorrelated noise, presumably of astrophysical origin, in the pulse arrival time (PAT) residuals for some of them. In most cases, pulsars in globular ...
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 ...
Astrometric Effects of Secular Aberration
(arXiv, 2005)
One of the main endeavors of fundamental astrometry is to establish a practical realization of an inertial reference frame anchored to celestial objects whose positions are defined in the barycentric coordinates of the ...
Towards a High Diffraction Efficiency of Photorefractive Multiple Quantum Wells
(American Institute of Physics, 2005)
We propose a method to improve the diffraction efficiency of photorefractive multiple quantum well devices in the transverse-field geometry. Higher efficiencies have been achieved through systematic electrical modulation studies.
Quasiparticle self-energy and many-body effective mass enhancement in a two-dimensional electron liquid
(American Physical Society, 2005)
Motivated by a number of recent experimental studies we have revisited the problem of the microscopic calculation of the quasiparticle self-energy and many-body effective mass enhancement in an unpolarized two- dimensional ...
RKKY range function of a one-dimensional noninteracting electron gas
(American Physical Society, 2005)
We show that the pitfalls encountered in earlier calculations of the RKKY range function for a noninteracting one- dimensional electron gas at zero temperature can be unraveled and successfully dealt with through a proper ...
Role of Physical Mechanisms in Biological Self-Organization
(American Physical Society, 2005)
Organs form during morphogenesis, the process that gives rise to specialized biological structures of specific shape and function in early embryonic development. Morphogenesis is under strict genetic control, but shape ...
Inertia of Intrinsic Spin
(arXiv, 2005)
The state of a particle in space and time is characterized by its mass and spin, which therefore determine the inertial properties of the particle. The coupling of intrinsic spin with rotation is examined and the corresponding ...
Beyond Gravitoelectromagnetism: Critical Speed in Gravitational Motion
(arXiv, 2005)
A null ray approaching a distant astronomical source appears to slow down, while a massive particle speeds up in accordance with Newtonian gravitation. The integration of these apparently incompatible aspects of motion in ...
A Mission to Explore the Pioneer Anomaly
(arXiv, 2005)
The Pioneer 10 and 11 spacecraft yielded the most precise navigation in deep space to date. These spacecraft had exceptional acceleration sensitivity. However, analysis of their radio-metric tracking data has consistently ...