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Lepidobatrachus laevis
Number of Pages: 16Integrative BiologyGeological Science
A Holographic Prediction of the Deconfinement Temperature
We argue that deconfinement in AdS/QCD models occurs via a first order
Hawking-Page type phase transition between a low temperature thermal AdS space
and a high temperature black hole. Such a result is consistent with the
expected temperature independence, to leading order in 1/N_c, of the meson
spectrum and spatial Wilson loops below the deconfinement temperature. As a
byproduct, we obtain model dependent deconfinement temperatures T_c in the hard
and soft wall models of AdS/QCD. Our result for T_c in the soft wall model is
close to a recent lattice prediction.Comment: 4 pages, 1 figure; v2 ref added, minor changes; v3 refs added,
discussion modified, to appear in PR
Observations of the plasma flow in comet P/SwiftâTuttle
We present direct ground based observations of the plasma flow sunward and tailward of the nucleus of comet P/SwiftâTuttle. The observations are longâslit high resolution spectra of the H_2O^+ emission centered at 6199Ă
with a velocity resolution of about 7 km s^(â1) (FWHM) and a spatial resolution of about 10^4 km at the comet. Emission is visible from just inside the predicted position of the cometopause on the sunward side of the nucleus out to 5 Ă 10^5 km on the tailward side. The deceleration of the solar plasma on the sunward side is clearly observed as is the acceleration of cometary ions into the tail. These observations show the effectiveness of ground based methods for the systematic study of cometary plasmas and point to the need for a better theoretical understanding of their acceleration mechanisms
Ion beam sputter etching of orthopedic implanted alloy MP35N and resulting effects on fatigue
The effects of two types of argon ion sputter etched surface structures on the tensile stress fatigue properties of orthopedic implant alloy MP35N were investigated. One surface structure was a natural texture resulting from direct bombardment by 1 keV argon ions. The other structure was a pattern of square holes milled into the surface by a 1 keV argon ion beam through a Ni screen mask. The etched surfaces were subjected to tensile stress only in fatigue tests designed to simulate the cyclic load conditions experienced by the stems of artificial hip joint implants. Both types of sputter etched surface structures were found to reduce the fatigue strength below that of smooth surface MP35N
Effects of Isolated Hip Abductor Fatigue on Frontal Plane Knee Mechanics
Purpose: Anterior cruciate ligament injuries and patellofemoral pain syndrome are both common and significant injuries to the knee that have been associated with hip weakness. Prospective studies have linked the risk of experiencing either injury to alterations in the frontal plane knee angle and moment during activity. These components of knee mechanics are theorized to be affected by hip abductor weakness. The purpose of this study was to identify the effects of isolated hip abductor fatigue-induced weakness on lower extremity kinematics and kinetics in recreationally active women
Spitzer Observations of Black Hole Low-mass X-ray Binaries: Assessing the Non-stellar Infrared Component
We have combined ground-based optical and near-infrared data with Spitzer Space Telescope mid-infrared data for five black hole (BH) soft X-ray transients (SXTs) in order to determine the levels of near- and mid-infrared emission from sources other than the secondary star. Mid-infrared emission from an accretion disk, circumbinary dust, and/or a jet could act as sources of near-infrared contamination, thereby diluting ellipsoidal variations of the secondary star and affecting determined BH mass estimates. Based on optical to mid-infrared spectral energy distribution modeling of the five SXTs along with the prototype, V616 Mon, we detected mid-infrared excesses in half of the systems, and suggest that the excesses detected from these systems arise from non-thermal synchrotron jets rather than circumbinary dust disks
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