160 research outputs found
Comparison of physical fitness between healthy and mildâtoâmoderate asthmatic children with exercise symptoms: A crossâsectional study
.Objective
Asthma is a chronic disease that may affect physical fitness, although its primary effects on exercise capacity, muscle strength, functionality and lifestyle, in children and adolescents, are still poorly understood. This study aimed to evaluate the differences in cardiorespiratory fitness, muscle strength, lifestyle, lung function, and functionality between asthmatics with exercise symptoms and healthy children. In addition, we have analyzed the association between clinical history and the presence of asthma.
Study Design
Cross-sectional study including 71 patients with a diagnosis of asthma and 71 healthy children and adolescents (7â17 years of age). Anthropometric data, clinical history, disease control, lifestyle (KIDMED and physical activity questionnaires), lung function (spirometry), exercise-induced bronchoconstriction test, aerobic fitness (cardiopulmonary exercise test), muscle strength and functionality (timed up and go; timed up and down stairs) were evaluated.
Results
Seventy-one patients with asthma (mean age 11.5â±â2.7) and 71 healthy subjects (mean age 10.7â±â2.5) were included. All asthmatic children had mild to moderate and stable asthma. EIB occurred in 56.3% of asthmatic children. Lung function was significantly (pâ<â.05) lower in the asthmatic group when compared to healthy peers, as well as the cardiorespiratory fitness, muscle strength, lifestyle and functionality. Moreover, asthmatic children were more likely to have atopic dermatitis, allergic reactions, food allergies, and a family history of asthma when compared to healthy children.
Conclusions
Children with mild-to-moderate asthma presenting exercise symptoms show a reduction in cardiorespiratory fitness, muscle strength, lung function, functionality, and lifestyle when compared to healthy peers. The study provides data for pediatricians to support exercise practice aiming to improve prognosis and quality of life in asthmatic children.S
Euclid preparation: XVI. Exploring the ultra-low surface brightness Universe with Euclid /VIS
Context. While Euclid is an ESA mission specifically designed to investigate the nature of dark energy and dark matter, the planned unprecedented combination of survey area (âŒ15Ăą 000 deg2), spatial resolution, low sky-background, and depth also make Euclid an excellent space observatory for the study of the low surface brightness Universe. Scientific exploitation of the extended low surface brightness structures requires dedicated calibration procedures that are yet to be tested. Aims. We investigate the capabilities of Euclid to detect extended low surface brightness structure by identifying and quantifying sky-background sources and stray-light contamination. We test the feasibility of generating sky flat-fields to reduce large-scale residual gradients in order to reveal the extended emission of galaxies observed in the Euclid survey. Methods. We simulated a realistic set of Euclid/VIS observations, taking into account both instrumental and astronomical sources of contamination, including cosmic rays, stray-light, zodiacal light, interstellar medium, and the cosmic infrared background, while simulating the effects of background sources in the field of view. Results. We demonstrate that a combination of calibration lamps, sky flats, and self-calibration would enable recovery of emission at a limiting surface brightness magnitude of ÎŒlim = 29.5-0.27+0.08 mag arcsec-2 (3Ï, 10Ăą ĂĂą 10 arcsec2) in the Wide Survey, and it would reach regions deeper by 2 mag in the Deep Surveys. Conclusions.Euclid/VIS has the potential to be an excellent low surface brightness observatory. Covering the gap between pixel-To-pixel calibration lamp flats and self-calibration observations for large scales, the application of sky flat-fielding will enhance the sensitivity of the VIS detector at scales larger than 1âł, up to the size of the field of view, enabling Euclid to detect extended surface brightness structures below ÎŒlimĂą =Ăą 31 mag arcsec-2 and beyond
Euclid preparation: XV. Forecasting cosmological constraints for the Euclid and CMB joint analysis
The combination and cross-correlation of the upcoming Euclid data with cosmic microwave background (CMB) measurements is a source of great expectation since it will provide the largest lever arm of epochs, ranging from recombination to structure formation across the entire past light cone. In this work, we present forecasts for the joint analysis of Euclid and CMB data on the cosmological parameters of the standard cosmological model and some of its extensions. This work expands and complements the recently published forecasts based on Euclid-specific probes, namely galaxy clustering, weak lensing, and their cross-correlation. With some assumptions on the specifications of current and future CMB experiments, the predicted constraints are obtained from both a standard Fisher formalism and a posterior-fitting approach based on actual CMB data. Compared to a Euclid-only analysis, the addition of CMB data leads to a substantial impact on constraints for all cosmological parameters of the standard Î-cold-dark-matter model, with improvements reaching up to a factor of ten. For the parameters of extended models, which include a redshift-dependent dark energy equation of state, non-zero curvature, and a phenomenological modification of gravity, improvements can be of the order of two to three, reaching higher than ten in some cases. The results highlight the crucial importance for cosmological constraints of the combination and cross-correlation of Euclid probes with CMB data
Euclid preparation: XIII. Forecasts for galaxy morphology with the Euclid Survey using deep generative models
We present a machine learning framework to simulate realistic galaxies for the Euclid Survey, producing more complex and realistic galaxies than the analytical simulations currently used in Euclid. The proposed method combines a control on galaxy shape parameters offered by analytic models with realistic surface brightness distributions learned from real Hubble Space Telescope observations by deep generative models. We simulate a galaxy field of 0.4 deg2 as it will be seen by the Euclid visible imager VIS, and we show that galaxy structural parameters are recovered to an accuracy similar to that for pure analytic SĂ©rsic profiles. Based on these simulations, we estimate that the Euclid Wide Survey (EWS) will be able to resolve the internal morphological structure of galaxies down to a surface brightness of 22.5 mag arcsec-2, and the Euclid Deep Survey (EDS) down to 24.9 mag arcsec-2. This corresponds to approximately 250 million galaxies at the end of the mission and a 50% complete sample for stellar masses above 1010.6 M (resp. 109.6 M) at a redshift z ⌠0.5 for the EWS (resp. EDS). The approach presented in this work can contribute to improving the preparation of future high-precision cosmological imaging surveys by allowing simulations to incorporate more realistic galaxies
Euclid Preparation. XXVIII. Forecasts for ten different higher-order weak lensing statistics
Recent cosmic shear studies have shown that higher-order statistics (HOS)
developed by independent teams now outperform standard two-point estimators in
terms of statistical precision thanks to their sensitivity to the non-Gaussian
features of large-scale structure. The aim of the Higher-Order Weak Lensing
Statistics (HOWLS) project is to assess, compare, and combine the constraining
power of ten different HOS on a common set of -like mocks, derived from
N-body simulations. In this first paper of the HOWLS series, we computed the
nontomographic (, ) Fisher information for the
one-point probability distribution function, peak counts, Minkowski
functionals, Betti numbers, persistent homology Betti numbers and heatmap, and
scattering transform coefficients, and we compare them to the shear and
convergence two-point correlation functions in the absence of any systematic
bias. We also include forecasts for three implementations of higher-order
moments, but these cannot be robustly interpreted as the Gaussian likelihood
assumption breaks down for these statistics. Taken individually, we find that
each HOS outperforms the two-point statistics by a factor of around two in the
precision of the forecasts with some variations across statistics and
cosmological parameters. When combining all the HOS, this increases to a
times improvement, highlighting the immense potential of HOS for cosmic shear
cosmological analyses with . The data used in this analysis are
publicly released with the paper.Comment: 33 pages, 24 figures, main results in Fig. 19 & Table 5, version
published in A&
Euclid preparation XVIII. The NISP photometric system
Euclid will be the first space mission to survey most of the extragalactic sky in the 0.95â2.02 ”m range, to a 5 Ï point-source median depth of 24.4 AB mag. This unique photometric dataset will find wide use beyond Euclidâs core science. In this paper, we present accurate computations of the Euclid YE, JE, and HE passbands used by the Near-Infrared Spectrometer and Photometer (NISP), and the associated photometric system. We pay particular attention to passband variations in the field of view, accounting for, among other factors, spatially variable filter transmission and variations in the angle of incidence on the filter substrate using optical ray tracing. The response curvesâ cut-on and cut-off wavelengths â and their variation in the field of view â are determined with âŒ0.8 nm accuracy, essential for the photometric redshift accuracy required by Euclid. After computing the photometric zero points in the AB mag system, we present linear transformations from and to common ground-based near-infrared photometric systems, for normal stars, red and brown dwarfs, and galaxies separately. A Python tool to compute accurate magnitudes for arbitrary passbands and spectral energy distributions is provided. We discuss various factors, from space weathering to material outgassing, that may slowly alter Euclidâs spectral response. At the absolute flux scale, the Euclid in-flight calibration program connects the NISP photometric system to Hubble Space Telescope spectrophotometric white dwarf standards; at the relative flux scale, the chromatic evolution of the response is tracked at the milli-mag level. In this way, we establish an accurate photometric system that is fully controlled throughout Euclidâs lifetime
Euclid Preparation TBD. Characterization of convolutional neural networks for the identification of galaxy-galaxy strong lensing events
Forthcoming imaging surveys will potentially increase the number of known
galaxy-scale strong lenses by several orders of magnitude. For this to happen,
images of tens of millions of galaxies will have to be inspected to identify
potential candidates. In this context, deep learning techniques are
particularly suitable for the finding patterns in large data sets, and
convolutional neural networks (CNNs) in particular can efficiently process
large volumes of images. We assess and compare the performance of three network
architectures in the classification of strong lensing systems on the basis of
their morphological characteristics. We train and test our models on different
subsamples of a data set of forty thousand mock images, having characteristics
similar to those expected in the wide survey planned with the ESA mission
\Euclid, gradually including larger fractions of faint lenses. We also evaluate
the importance of adding information about the colour difference between the
lens and source galaxies by repeating the same training on single-band and
multi-band images. Our models find samples of clear lenses with
precision and completeness, without significant differences in the performance
of the three architectures. Nevertheless, when including lenses with fainter
arcs in the training set, the three models' performance deteriorates with
accuracy values of to depending on the model. Our
analysis confirms the potential of the application of CNNs to the
identification of galaxy-scale strong lenses. We suggest that specific training
with separate classes of lenses might be needed for detecting the faint lenses
since the addition of the colour information does not yield a significant
improvement in the current analysis, with the accuracy ranging from
to for the different models
Euclid preparation. XVIII. The NISP photometric system
Euclid will be the first space mission to survey most of the extragalactic
sky in the 0.95-2.02 m range, to a 5 point-source median depth of
24.4 AB mag. This unique photometric data set will find wide use beyond
Euclid's core science. In this paper, we present accurate computations of the
Euclid Y_E, J_E and H_E passbands used by the Near-Infrared Spectrometer and
Photometer (NISP), and the associated photometric system. We pay particular
attention to passband variations in the field of view, accounting among others
for spatially variable filter transmission, and variations of the angle of
incidence on the filter substrate using optical ray tracing. The response
curves' cut-on and cut-off wavelengths - and their variation in the field of
view - are determined with 0.8 nm accuracy, essential for the photometric
redshift accuracy required by Euclid. After computing the photometric
zeropoints in the AB mag system, we present linear transformations from and to
common ground-based near-infrared photometric systems, for normal stars, red
and brown dwarfs, and galaxies separately. A Python tool to compute accurate
magnitudes for arbitrary passbands and spectral energy distributions is
provided. We discuss various factors from space weathering to material
outgassing that may slowly alter Euclid's spectral response. At the absolute
flux scale, the Euclid in-flight calibration program connects the NISP
photometric system to Hubble Space Telescope spectrophotometric white dwarf
standards; at the relative flux scale, the chromatic evolution of the response
is tracked at the milli-mag level. In this way, we establish an accurate
photometric system that is fully controlled throughout Euclid's lifetime.Comment: 33 pages, 25 figures, accepted for publication in A&
Euclid preparation: I. the Euclid Wide Survey
Euclid is a mission of the European Space Agency that is designed to constrain the properties of dark energy and gravity via weak gravitational lensing and galaxy clustering. It will carry out a wide area imaging and spectroscopy survey (the Euclid Wide Survey: EWS) in visible and near-infrared bands, covering approximately 15 000 deg2 of extragalactic sky in six years. The wide-field telescope and instruments are optimised for pristine point spread function and reduced stray light, producing very crisp images. This paper presents the building of the Euclid reference survey: The sequence of pointings of EWS, deep fields, and calibration fields, as well as spacecraft movements followed by Euclid as it operates in a step-And-stare mode from its orbit around the Lagrange point L2. Each EWS pointing has four dithered frames; we simulated the dither pattern at the pixel level to analyse the effective coverage. We used up-To-date models for the sky background to define the Euclid region-of-interest (RoI). The building of the reference survey is highly constrained from calibration cadences, spacecraft constraints, and background levels; synergies with ground-based coverage were also considered. Via purposely built software, we first generated a schedule for the calibrations and deep fields observations. On a second stage, the RoI was tiled and scheduled with EWS observations, using an algorithm optimised to prioritise the best sky areas, produce a compact coverage, and ensure thermal stability. The result is the optimised reference survey RSD-2021A, which fulfils all constraints and is a good proxy for the final solution. The current EWS covers âŒ14.500 deg2. The limiting AB magnitudes (5Ïpoint-like source) achieved in its footprint are estimated to be 26.2 (visible band IE) and 24.5 (for near infrared bands YE, JE, HE); for spectroscopy, the Hα line flux limit is 2.10-16 erg-1 cm-2 s-1 at 1600 nm; and for diffuse emission, the surface brightness limits are 29.8 (visible band) and 28.4 (near infrared bands) mag arcsec-2
Euclid preparation. XXV. The Euclid Morphology Challenge -- Towards model-fitting photometry for billions of galaxies
The ESA Euclid mission will provide high-quality imaging for about 1.5
billion galaxies. A software pipeline to automatically process and analyse such
a huge amount of data in real time is being developed by the Science Ground
Segment of the Euclid Consortium; this pipeline will include a model-fitting
algorithm, which will provide photometric and morphological estimates of
paramount importance for the core science goals of the mission and for legacy
science. The Euclid Morphology Challenge is a comparative investigation of the
performance of five model-fitting software packages on simulated Euclid data,
aimed at providing the baseline to identify the best suited algorithm to be
implemented in the pipeline. In this paper we describe the simulated data set,
and we discuss the photometry results. A companion paper (Euclid Collaboration:
Bretonni\`ere et al. 2022) is focused on the structural and morphological
estimates. We created mock Euclid images simulating five fields of view of 0.48
deg2 each in the band of the VIS instrument, each with three realisations
of galaxy profiles (single and double S\'ersic, and 'realistic' profiles
obtained with a neural network); for one of the fields in the double S\'ersic
realisation, we also simulated images for the three near-infrared ,
and bands of the NISP-P instrument, and five Rubin/LSST optical
complementary bands (, , , , and ). To analyse the results we
created diagnostic plots and defined ad-hoc metrics. Five model-fitting
software packages (DeepLeGATo, Galapagos-2, Morfometryka, ProFit, and
SourceXtractor++) were compared, all typically providing good results. (cut)Comment: 29 pages, 33 figures. Euclid pre-launch key paper. Companion paper:
Bretonniere et al. 202
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