2,867 research outputs found
Vortex Glass is a Metal: Unified Theory of the Magnetic Field and Disorder-Tuned Bose Metals
We consider the disordered quantum rotor model in the presence of a magnetic
field. We analyze the transport properties in the vicinity of the multicritical
point between the superconductor, phase glass and paramagnetic phases. We find
that the magnetic field leaves metallic transport of bosons in the glassy phase
in tact. In the vicinity of the vicinity of the superconductivity-to-Bose metal
transition, the resistitivy turns on as with . This
functional form is in excellent agreement with the experimentally observed
turn-on of the resistivity in the metallic state in MoGe, namely , . The metallic state is also shown to presist in
three spatial dimensions. In addition, we also show that the metallic state
remains intact in the presence of Ohmic dissipation in spite of recent claims
to the contrary. As the phase glass in is identical to the vortex glass,
we conclude that the vortex glass is, in actuality, a metal rather than a
superconductor at T=0. Our analysis unifies the recent experiments on vortex
glass systems in which the linear resistivity remained non-zero below the
putative vortex glass transition and the experiments on thin films in which a
metallic phase has been observed to disrupt the direct transition from a
superconductor to an insulator.Comment: Published version with an appendix showing that the claim in
cond-mat/0510380 (and cond-mat/0606522) that Ohmic dissipation in the phase
glass leads to a superconducting state is false. A metal persists in this
case as wel
Equilibrium extraction characteristics of alkyl amines and nuclear fuel metals in nitrate systems: progress report for the period January 1 - September 31 [sic], 1963 : progress report XII
"December 2, 1963."Includes bibliographical references (pages 29-30)Progress report no. XII; January 1, 1963 - September 30, 1963Work performed under subcontract no. 1327 under contract no. W -7405 - Eng - 26 with Union Carbide Nuclear Corporation Oak Ridge, Tennesse
Equilibrium extraction characteristics of alkyl amines and nuclear fuel metals in nitrate systems: progress report for the period October 1 - May 30, 1964 : progress report XIII
"August 3, 1964."Includes bibliographical references (page 32)Progress report no. XIII; October 1, 1963 - May 30, 1964Work performed under subcontract no. 1327 under contract no. W -7405 - Eng - 26 with Union Carbide Nuclear Corporation Oak Ridge, Tennesse
Improving prostate cancer detection in veterans through the development of a clinical decision rule for prostate biopsy
BACKGROUND: We sought to improve prostate cancer (PC) detection through developing a prostate biopsy clinical decision rule (PBCDR), based on an elevated PSA and laboratory biomarkers. This decision rule could be used after initial PC screening, providing the patient and clinician information to consider prior to biopsy. METHODS: This case–control study evaluated men from the Tampa, Florida, James A. Haley (JH) Veteran’s Administration (VA) (N = 1,378), from January 1, 1998, through April 15, 2005. To assess the PBCDR we did all of the following: 1) Identified biomarkers that are related to PC and have the capability of improving the efficiency of PC screening; 2) Developed statistical models to determine which can best predict the probability of PC; 3) Compared each potential model to PSA alone using Receiver Operator Characteristic (ROC) curves, to evaluate for improved overall effectiveness in PC detection and reduction in (negative) biopsies; and 4) Evaluated dose–response relationships between specified lab biomarkers (surrogates for extra-prostatic disease development) and PC progression. RESULTS: The following biomarkers were related to PC: hemoglobin (HGB) (OR = 1.42 95% CI 1.27, 1.59); red blood cell (RBC) count (OR = 2.52 95% CI 1.67, 3.78); PSA (OR = 1.04 95% CI 1.03, 1.05); and, creatinine (OR = 1.55 95% CI 1.12, 2.15). Comparing all PC stages versus non-cancerous conditions, the ROC curve area under the curve (AUC) enlarged (increasing the probability of correctly classifying PC): PSA (alone) 0.59 (95% CI 0.55, 0.61); PBCDR model 0.68 (95% CI 0.65, 0.71), and the positive predictive value (PPV) increased: PSA 44.7%; PBCDR model 61.8%. Comparing PC (stages II, III, IV) vs. other, the ROC AUC increased: PSA (alone) 0.63 (95% CI 0.58, 0.66); PBCDR model 0.72 (95% CI 0.68, 0.75), and the PPV increased: 20.6% (PSA); PBCDR model 55.3%. CONCLUSIONS: These results suggest evaluating certain common biomarkers in conjunction with PSA may improve PC prediction prior to biopsy. Moreover, these biomarkers may be more helpful in detecting clinically relevant PC. Follow-up studies should begin with replicating the study on different U.S. VA patients involving multiple practices
High-throughput Saccharification Assay for Lignocellulosic Materials
Polysaccharides that make up plant lignocellulosic biomass can be broken down to produce a range of sugars that subsequently can be
used in establishing a biorefinery. These raw materials would constitute a new industrial platform, which is both sustainable and carbon neutral, to replace
the current dependency on fossil fuel. The recalcitrance to deconstruction observed in lignocellulosic materials is produced by several intrinsic properties
of plant cell walls. Crystalline cellulose is embedded in matrix polysaccharides such as xylans and arabinoxylans, and the whole structure is encased by the
phenolic polymer lignin, that is also difficult to digest 1. In order to improve the digestibility of plant materials we need to discover the main bottlenecks
for the saccharification of cell walls and also screen mutant and breeding populations to evaluate the variability in saccharification 2. These tasks require
a high throughput approach and here we present an analytical platform that can perform saccharification analysis in a 96-well plate format. This platform has
been developed to allow the screening of lignocellulose digestibility of large populations from varied plant species. We have scaled down the reaction volumes
for gentle pretreatment, partial enzymatic hydrolysis and sugar determination, to allow large numbers to be assessed rapidly in an automated system
Correcting the z~8 Galaxy Luminosity Function for Gravitational Lensing Magnification Bias
We present a Bayesian framework to account for the magnification bias from
both strong and weak gravitational lensing in estimates of high-redshift galaxy
luminosity functions. We illustrate our method by estimating the UV
luminosity function using a sample of 97 Y-band dropouts (Lyman break galaxies)
found in the Brightest of Reionizing Galaxies (BoRG) survey and from the
literature. We find the luminosity function is well described by a Schechter
function with characteristic magnitude of ,
faint-end slope of , and number density of
. These
parameters are consistent within the uncertainties with those inferred from the
same sample without accounting for the magnification bias, demonstrating that
the effect is small for current surveys at , and cannot account for the
apparent overdensity of bright galaxies compared to a Schechter function found
recently by Bowler et al. (2014a,b) and Finkelstein et al. (2014). We estimate
that the probability of finding a strongly lensed source in our sample
is in the range depending on limiting magnitude. We identify one
strongly-lensed candidate and three cases of intermediate lensing in BoRG
(estimated magnification ) in addition to the previously known
candidate group-scale strong lens. Using a range of theoretical luminosity
functions we conclude that magnification bias will dominate wide field surveys
-- such as those planned for the Euclid and WFIRST missions -- especially at
. Magnification bias will need to be accounted for in order to derive
accurate estimates of high-redshift luminosity functions in these surveys and
to distinguish between galaxy formation models.Comment: Accepted for publication in ApJ. 20 pages, 13 figure
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