530 research outputs found
Effect of residual stress on recrystallization behavior of mechanically alloyed steels
This paper presents a finite element modeling analysis of deformation on iron-base mechanically alloyed oxide dispersion
strengthened alloy by spherical indentations (Brinell test). Results of the model are used to interpret the role of residual shear stresses
on the development of recrystallized grain structure and the temperature at which recrystallization occurs.I. Toda Caraballo acknowledges the Spanish
Ministerio de Ciencia e Inovacio´n for financial support
in the form of Ph.D. research grant (FPI). The authors
acknowledge financial support for this investigation
from the Spanish Ministerio de Educacio´n y Ciencia
through the Plan Nacional 2006 ENE2006-15170-C02-
01/ALT.Peer reviewe
Factors associated with allergic rhinitis in colombian subpopulations aged 1 to 17 and 18 to 59
Background: Several studies have shown variations in the prevalence of allergic rhinitis (AR) around the world, and different potential predisposing factors. More studies are needed on risk factors, specifically in developing countries. This study explored the association of several factors and AR among urban residents in six cities of Colombia. Methodology: A cross-sectional study and a nested case-control study were carried out between 2009 and 2010 involving two Colombian subpopulations: children/adolescents and adults. Cases were affirmative respondents to “In the past 12 months, have you (or your child) had a problem with sneezing or a running or blocked nose, when you (or your child) did not have a cold or the flu?” “Controls” were subjects who never had been diagnosed with asthma, AR or atopic eczema by a physician, and whom did not report any symptoms in the past twelve months. Weighted logistic regression was used to assess the association of different factors with case/control status. Results: Factors associated with AR in children/adolescents were family history of AR, acetaminophen consumption and high socioeconomic status. Among adults, family history of asthma, AR and atopic eczema, and cetaminophen consumption were associated with AR. Consumption of cereals among children/adolescents and eating eggs among adults showed protective associations. Conclusions: Our findings suggest the presence of previously unknown cultural, environmental and family factors associated with the presence of AR in Colombia. © 2016, AMC. All rights reserved
Treatment of electrical status epilepticus in sleep : A pooled analysis of 575 cases
OBJECTIVE: Epileptic encephalopathy with electrical status epilepticus in sleep (ESES) is a pediatric epilepsy syndrome with sleep-induced epileptic discharges and acquired impairment of cognition or behavior. Treatment of ESES is assumed to improve cognitive outcome. The aim of this study is to create an overview of the current evidence for different treatment regimens in children with ESES syndrome. METHODS: A literature search using PubMed and Embase was performed. Articles were selected that contain original treatment data of patients with ESES syndrome. Authors were contacted for additional information. Individual patient data were collected, coded, and analyzed using logistic regression analysis. The three predefined main outcome measures were improvement in cognitive function, electroencephalography (EEG) pattern, and any improvement (cognition or EEG). RESULTS: The literature search yielded 1,766 articles. After applying inclusion and exclusion criteria, 112 articles and 950 treatments in 575 patients could be analyzed. Antiepileptic drugs (AEDs, n = 495) were associated with improvement (i.e., cognition or EEG) in 49% of patients, benzodiazepines (n = 171) in 68%, and steroids (n = 166) in 81%. Surgery (n = 62) resulted in improvement in 90% of patients. In a subgroup analysis of patients who were consecutively reported (585 treatments in 282 patients), we found improvement in a smaller proportion treated with AEDs (34%), benzodiazepines (59%), and steroids (75%), whereas the improvement percentage after surgery was preserved (93%). Possible predictors of improved outcome were treatment category, normal development before ESES onset, and the absence of structural abnormalities. SIGNIFICANCE: Although most included studies were small and retrospective and their heterogeneity allowed analysis of only qualitative outcome data, this pooled analysis suggests superior efficacy of steroids and surgery in encephalopathy with ESES
First Season QUIET Observations: Measurements of CMB Polarization Power Spectra at 43 GHz in the Multipole Range 25 <= ell <= 475
The Q/U Imaging ExperimenT (QUIET) employs coherent receivers at 43GHz and
95GHz, operating on the Chajnantor plateau in the Atacama Desert in Chile, to
measure the anisotropy in the polarization of the CMB. QUIET primarily targets
the B modes from primordial gravitational waves. The combination of these
frequencies gives sensitivity to foreground contributions from diffuse Galactic
synchrotron radiation. Between 2008 October and 2010 December, >10,000hours of
data were collected, first with the 19-element 43GHz array (3458hours) and then
with the 90-element 95GHz array. Each array observes the same four fields,
selected for low foregrounds, together covering ~1000deg^2. This paper reports
initial results from the 43GHz receiver which has an array sensitivity to CMB
fluctuations of 69uK sqrt(s). The data were extensively studied with a large
suite of null tests before the power spectra, determined with two independent
pipelines, were examined. Analysis choices, including data selection, were
modified until the null tests passed. Cross correlating maps with different
telescope pointings is used to eliminate a bias. This paper reports the EE, BB
and EB power spectra in the multipole range ell=25-475. With the exception of
the lowest multipole bin for one of the fields, where a polarized foreground,
consistent with Galactic synchrotron radiation, is detected with 3sigma
significance, the E-mode spectrum is consistent with the LCDM model, confirming
the only previous detection of the first acoustic peak. The B-mode spectrum is
consistent with zero, leading to a measurement of the tensor-to-scalar ratio of
r=0.35+1.06-0.87. The combination of a new time-stream double-demodulation
technique, Mizuguchi-Dragone optics, natural sky rotation, and frequent
boresight rotation leads to the lowest level of systematic contamination in the
B-mode power so far reported, below the level of r=0.1Comment: 19 pages, 14 figures, higher quality figures are available at
http://quiet.uchicago.edu/results/index.html; Fixed a typo and corrected
statistical error values used as a reference in Figure 14, showing our
systematic uncertainties (unchanged) vs. multipole; Revision to ApJ accepted
version, this paper should be cited as "QUIET Collaboration et al. (2011)
The QUIJOTE experiment: project overview and first results
QUIJOTE (Q-U-I JOint TEnerife) is a new polarimeter aimed to characterize the
polarization of the Cosmic Microwave Background and other Galactic and
extragalactic signals at medium and large angular scales in the frequency range
10-40 GHz. The multi-frequency (10-20~GHz) instrument, mounted on the first
QUIJOTE telescope, saw first light on November 2012 from the Teide Observatory
(2400~m a.s.l). During 2014 the second telescope has been installed at this
observatory. A second instrument at 30~GHz will be ready for commissioning at
this telescope during summer 2015, and a third additional instrument at 40~GHz
is now being developed. These instruments will have nominal sensitivities to
detect the B-mode polarization due to the primordial gravitational-wave
component if the tensor-to-scalar ratio is larger than r=0.05.Comment: To appear in "Highlights of Spanish Astrophysics VIII", Proceedings
of the XI Scientific Meeting of the Spanish Astronomical Society, Teruel,
Spain (2014
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