10,244 research outputs found
Magnetization and Loss Measurements of YBCO CORC and Roebel Cables for Accelerators using ±T dipole Susceptometer
This CORC sample Magnetization reaches about 900 kA/m (cable volume) and 2200 kA/m (strand volume) near injection
This Roebel cable reaches about 2000 kA/m (cable volume) and 2400 kA/m (strand volume) near injection
These values agree well with individual tape values if (i) we normalize to strand volume, Correct CORC for twisting
These values can be compared to
NbTi Minj = 10 kA/m b3 = 3-6 units
Nb3Sn Minj = 100 kA/m b3 = 30 units
Here Minj is 100 X higher than NbTi and 10 X higher than NbTi
Not insurmountable, but must be considered when thinking about particle beam steering magnet qualit
Semi-Empirical Cepheid Period-Luminosity Relations in Sloan Magnitudes
In this paper we derive semi-empirical Cepheid period-luminosity (P-L)
relations in the Sloan ugriz magnitudes by combining the observed BVI mean
magnitudes from the Large Magellanic Cloud Cepheids (LMC) and theoretical
bolometric corrections. We also constructed empirical gr band P-L relations,
using the publicly available Johnson-Sloan photometric transformations, to be
compared with our semi-empirical P-L relations. These two sets of P-L relations
are consistent with each other.Comment: 4 pages, 2 tables and 2 figures, ApJ accepte
Modeling the IDV emissions of the BL Lac Objects with a Langevin type stochastic differential equation
In this paper, we introduce a simplified model for explaining the
observations of the optical intraday variability (IDV) of the BL Lac Objects.
We assume that the source of the IDV are the stochastic oscillations of an
accretion disk around a supermassive black hole. The Stochastic Fluctuations on
the vertical direction of the accretion disk are described by using a Langevin
type equation with a damping term and a random, white noise type force.
Furthermore, the preliminary numerical simulation results are presented, which
are based on the numerical analysis of the Langevin stochastic differential
equation.Comment: 4 pages, 4 figures, accepted for publication in J. Astrophys. Ast
Center Vortex Model for the Infrared Sector of SU(3) Yang-Mills Theory - Vortex Free Energy
The vortex free energy is studied in the random vortex world-surface model of
the infrared sector of SU(3) Yang-Mills theory. The free energy of a center
vortex extending into two spatial directions, which is introduced into
Yang-Mills configurations when acting with the 't Hooft loop operator, is
verified to furnish an order parameter for the deconfinement phase transition.
It is shown to exhibit a weak discontinuity at the critical temperature,
corresponding to the weak first order character of the transition.Comment: 13 pages, 2 figures containing 3 eps file
Protein sliding and hopping kinetics on DNA
Using Monte-Carlo simulations, we deconvolved the sliding and hopping
kinetics of GFP-LacI proteins on elongated DNA from their experimentally
observed seconds-long diffusion trajectories. Our simulations suggest the
following results: (1) in each diffusion trajectory, a protein makes on average
hundreds of alternating slides and hops with a mean sliding time of several
tens of ms; (2) sliding dominates the root mean square displacement of fast
diffusion trajectories, whereas hopping dominates slow ones; (3) flow and
variations in salt concentration have limited effects on hopping kinetics,
while in vivo DNA configuration is not expected to influence sliding kinetics;
furthermore, (4) the rate of occurrence for hops longer than 200 nm agrees with
experimental data for EcoRV proteins
Sulfur Status In Long Distance Runners
In sports medicine, sulfur plays an important role and its deficiency can cause muscle injury affecting the performance of the athletes. However, its evaluation is unusual in conventional clinical practice. In this study the sulfur levels were determined in Brazilian amateur athlete's blood using Neutron Activation Analyses (NAA) technique. Twenty six male amateur runners, age 18 to 36 years, participated of this study. The athletes had a balanced diet, without multivitamin/mineral supplements. The blood collection was performed at LABEX (Laboratorio de Bioquimica do Exercicio, UNICAMP-SP) and the samples were irradiated for 300 seconds in a pneumatic station in the nuclear reactor (IEA-R1, 3-4.5MW, pool type) at IPEN/CNEN-SP. The results were compared with the control group (subjects of same age but not involved with physical activities) and showed that the sulfur concentration was 44% higher in amateurs athletes than control group. These data can be considered for preparation of balanced diet, as well as contributing for proposing new protocols of clinical evaluation.63
A New Stellar Atmosphere Grid and Comparisons with HST/STIS Calspec Flux Distributions
The Space Telescope Imaging Spectrograph (STIS) has measured the spectral
energy distributions (SEDs) for several stars of types O, B, A, F, and G. These
absolute fluxes from the CALSPEC database are fit with a new spectral grid
computed from the ATLAS-APOGEE ATLAS9 model atmosphere database using a
chi-square minimization technique in four parameters. The quality of the fits
are compared for complete LTE grids by Castelli & Kurucz (CK04) and our new
comprehensive LTE grid (BOSZ). For the cooler stars, the fits with the MARCS
LTE grid are also evaluated, while the hottest stars are also fit with the NLTE
Lanz & Hubeny OB star grids. Unfortunately, these NLTE models do not transition
smoothly in the infrared to agree with our new BOSZ LTE grid at the NLTE lower
limit of Teff =15,000K.
The new BOSZ grid is available via the Space Telescope Institute MAST archive
and has a much finer sampled IR wavelength scale than CK04, which will
facilitate the modeling of stars observed by the James Webb Space Telescope
(JWST). Our result for the angular diameter of Sirius agrees with the ground-
based interferometric value.Comment: 11 figure
Clinical impact of double protease inhibitor boosting with Lopinavir/Ritonavir and Amprenavir as part of salvage antiretroviral therapy
Purpose: Double protease inhibitor (PI) boosting is being explored as a new strategy in salvage antiretroviral (ARV) therapy. However, if a negative drug interaction leads to decreased drug levels of either or both PIs, double PI boosting could lead to decreased virologic response. A negative drug interaction has been described between amprenavir (APV) and lopinavir/ritonavir (LPV/r). This observational cohort study assessed the virologic impact of the addition of APV to a salvage ARV regimen, which also contains LPV/r, compared to a regimen containing LPV/r alone. Method: Patients initiated on a salvage ARV regimen that included LPV/r obtained from the expanded access program in Toronto, Canada, were evaluated. APV (600-1,200 mg bid) was added at the discretion of the treating physician. Results: Using multivariate Cox proportional hazards models, we found that the addition of APV to a LPV/r-containing salvage regimen was not significantly associated with time to virologic suppression (< 50 copies/mL; adjusted hazard ratio [HR] = 0.75, p = .12) or with time to virologic rebound (adjusted HR = 1.46, p = .34). Those patients who received higher doses of APV had an increased chance of virologic suppression (p = .03). In a subset of 27 patients, the median LPV Ctrough was significantly lower in patients receiving APV (p = .04), and the median APV Ctrough was reduced compared to reported controls. Conclusion: Our data do not support an additional benefit in virologic reduction of double boosting with APV and LPV/r relative to LPV/r alone in salvage ARV therapy. Our study's limitations include its retrospective nature and the imbalance between the two groups potentially confounding the results. Although these factors were adjusted for in the multivariate analysis, a prospective randomized controlled trial is warranted to confirm our findings
Vibrational relaxation measurements in CO2 USING an induced fluorescence technique
Vibrational relaxation measurements in carbon dioxide using induced infrared fluorescence techniqu
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