26 research outputs found
The spinning artificial gravity environment: A design project
The SAGE, or Spinning Artificial Gravity Environment, design was carried out to develop an artificial gravity space station which could be used as a platform for the performance of medical research to determine the benefits of various, fractional gravity levels for astronauts normally subject to zero gravity. Desirable both for its medical research mission and a mission for the study of closed loop life-support and other factors in prolonged space flight, SAGE was designed as a low Earth orbiting, solar powered, manned space station
The GALEX Ultraviolet Atlas of Nearby Galaxies
We present images, integrated photometry, and surface-brightness and color profiles for a total of 1034 nearby galaxies recently observed by the Galaxy Evolution Explorer (GALEX) satellite in its far-ultraviolet (FUV; λ_(eff) = 1516 Å) and near-ultraviolet (NUV; λ_(eff) = 2267 Å) bands. Our catalog of objects is derived primarily from the GALEX Nearby Galaxies Survey (NGS) supplemented by galaxies larger than 1' in diameter serendipitously found in these fields and in other GALEX exposures of similar of greater depth. The sample analyzed here adequately describes the distribution and full range of properties (luminosity, color, star formation rate [SFR]) of galaxies in the local universe. From the surface brightness profiles obtained we have computed asymptotic magnitudes, colors, and luminosities, along with the concentration indices C31 and C42. We have also morphologically classified the UV surface brightness profiles according to their shape. This data set has been complemented with archival optical, near-infrared, and far-infrared fluxes and colors. We find that the integrated (FUV − K) color provides robust discrimination between elliptical and spiral/irregular galaxies and also among spiral galaxies of different subtypes. Elliptical galaxies with brighter K-band luminosities (i.e., more massive) are redder in (NUV − K) color but bluer in (FUV − NUV) (a color sensitive to the presence of a strong UV upturn) than less massive ellipticals. In the case of the spiral/irregular galaxies our analysis shows the presence of a relatively tight correlation between the (FUV − NUV) color (or, equivalently, the slope of the UV spectrum, β) and the total infrared-to-UV ratio. The correlation found between (FUV − NUV) color and K-band luminosity (with lower luminosity objects being bluer than more luminous ones) can be explained as due to an increase in the dust content with galaxy luminosity. The images in this Atlas along with the profiles and integrated properties are publicly available through a dedicated Web page
The GALEX Ultraviolet Atlas of Nearby Galaxies
We present images, integrated photometry, surface-brightness and color
profiles for a total of 1034 nearby galaxies recently observed by the GALEX
satellite in its far-ultraviolet (FUV; 1516A) and near-ultraviolet (NUV; 2267A)
bands. (...) This data set has been complemented with archival optical,
near-infrared, and far-infrared fluxes and colors. We find that the integrated
(FUV-K) color provides robust discrimination between elliptical and
spiral/irregular galaxies and also among spiral galaxies of different
sub-types. Elliptical galaxies with brighter K-band luminosities (i.e. more
massive) are redder in (NUV-K) color but bluer in (FUV-NUV) than less massive
ellipticals. In the case of the spiral/irregular galaxies our analysis shows
the presence of a relatively tight correlation between the (FUV-NUV) color and
the total infrared-to-UV ratio. The correlation found between (FUV-NUV) color
and K-band luminosity (with lower luminosity objects being bluer than more
luminous ones) can be explained as due to an increase in the dust content with
galaxy luminosity.
The images in this Atlas along with the profiles and integrated properties
are publicly available through a dedicated web page at
http://nedwww.ipac.caltech.edu/level5/GALEX_Atlas/Comment: 181 pages, 10 figures, accepted for publication in ApJS (abstract
abridged
The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe
The preponderance of matter over antimatter in the early Universe, the
dynamics of the supernova bursts that produced the heavy elements necessary for
life and whether protons eventually decay --- these mysteries at the forefront
of particle physics and astrophysics are key to understanding the early
evolution of our Universe, its current state and its eventual fate. The
Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed
plan for a world-class experiment dedicated to addressing these questions. LBNE
is conceived around three central components: (1) a new, high-intensity
neutrino source generated from a megawatt-class proton accelerator at Fermi
National Accelerator Laboratory, (2) a near neutrino detector just downstream
of the source, and (3) a massive liquid argon time-projection chamber deployed
as a far detector deep underground at the Sanford Underground Research
Facility. This facility, located at the site of the former Homestake Mine in
Lead, South Dakota, is approximately 1,300 km from the neutrino source at
Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino
charge-parity symmetry violation and mass ordering effects. This ambitious yet
cost-effective design incorporates scalability and flexibility and can
accommodate a variety of upgrades and contributions. With its exceptional
combination of experimental configuration, technical capabilities, and
potential for transformative discoveries, LBNE promises to be a vital facility
for the field of particle physics worldwide, providing physicists from around
the globe with opportunities to collaborate in a twenty to thirty year program
of exciting science. In this document we provide a comprehensive overview of
LBNE's scientific objectives, its place in the landscape of neutrino physics
worldwide, the technologies it will incorporate and the capabilities it will
possess.Comment: Major update of previous version. This is the reference document for
LBNE science program and current status. Chapters 1, 3, and 9 provide a
comprehensive overview of LBNE's scientific objectives, its place in the
landscape of neutrino physics worldwide, the technologies it will incorporate
and the capabilities it will possess. 288 pages, 116 figure
Individual, family, and social correlates of flourishing outcomes among youth: Findings from the 2016-2017 National Survey of Children\u27s Health.
BACKGROUND: Flourishing is considered an optimal state of well-being and is associated with positive psychological outcomes. Although, individual, family, and social factors may either facilitate or impede flourishing, their unique influence on flourishing outcomes is not well-understood among youth.
OBJECTIVE: Using data from the 2016-2017 National Survey of Children\u27s Health (NSCH), this study investigated cross-sectional associations among adverse family experiences (AFE), community safety, family resilience, parental aggravation, and flourishing among youth.
PARTICIPANTS AND SETTING: Data from the 2016-2017 NSCH (N = 51,156) were analyzed. Participants included males (n = 26,124) and females (n = 25,032) whose ages ranged from 6 to 17 years old (M = 12.14, SD = 3.45).
METHODS: After controlling for relevant demographics, adjusted odds ratios (AORs) using a single-block logistic regression determined the relative likelihood of flourishing.
RESULTS: Youth who experienced zero to one AFE (AOR = 2.10; 95% CI [1.95, 2.26]) and two to three AFEs (1.32 [1.20, 1.45]) were more likely to flourish than youth with four or more AFEs. Youth whose parents endorsed low parental aggravation (6.80 [6.41, 7.22]) and moderate parental aggravation (3.70 [3.51, 3.89]) were more likely to be flourishing than youth whose parents endorsed high parental aggravation.
CONCLUSIONS: Findings suggest that high parental aggravation is related to poorer flourishing outcomes, after considering community safety, family adversity, family resilience, and demographic characteristics. Providers should consider interventions to support the emotional regulation of parental systems as a means of maximizing developmental outcomes among youth
The GALEX Ultraviolet Atlas of Nearby Galaxies
181 pages, 10 figures, accepted for publication in ApJS (abstract abridged)We present images, integrated photometry, surface-brightness and color profiles for a total of 1034 nearby galaxies recently observed by the GALEX satellite in its far-ultraviolet (FUV; 1516A) and near-ultraviolet (NUV; 2267A) bands. (...) This data set has been complemented with archival optical, near-infrared, and far-infrared fluxes and colors. We find that the integrated (FUV-K) color provides robust discrimination between elliptical and spiral/irregular galaxies and also among spiral galaxies of different sub-types. Elliptical galaxies with brighter K-band luminosities (i.e. more massive) are redder in (NUV-K) color but bluer in (FUV-NUV) than less massive ellipticals. In the case of the spiral/irregular galaxies our analysis shows the presence of a relatively tight correlation between the (FUV-NUV) color and the total infrared-to-UV ratio. The correlation found between (FUV-NUV) color and K-band luminosity (with lower luminosity objects being bluer than more luminous ones) can be explained as due to an increase in the dust content with galaxy luminosity. The images in this Atlas along with the profiles and integrated properties are publicly available through a dedicated web page at http://nedwww.ipac.caltech.edu/level5/GALEX_Atlas
Radar rainfall uncertainty modelling influenced by wind
Radar-based estimates of rainfall are affected by many sources of uncertainties, which would propagate through the hydrological model when radar rainfall estimates are used as input or initial conditions. An elegant solution to quantify these uncertainties is to model the empirical relationship between radar measurements and rain gauge observations (as the ‘ground reference’). However, most current studies only use a fixed and uniform model to represent the uncertainty of radar rainfall, without consideration of its variation under different synoptic regimes. Wind is such a typical weather factor, as it not only induces error in rain gauge measurements but also causes the raindrops observed by weather radar to drift when they reach the ground. For this reason, as a first attempt, this study introduces the wind field into the uncertainty model and designs the radar rainfall uncertainty model under different wind conditions. We separate the original dataset into three subsamples according to wind speed, which are named as WDI (0–2 m/s), WDII (2–4 m/s) and WDIII (>4 m/s). The multivariate distributed ensemble generator is introduced and established for each subsample. Thirty typical events (10 at each wind range) are selected to explore the behaviours of uncertainty under different wind ranges. In each time step, 500 ensemble members are generated, and the values of 5th to 95th percentile values are used to produce the uncertainty bands. Two basic features of uncertainty bands, namely dispersion and ensemble bias, increase significantly with the growth of wind speed, demonstrating that wind speed plays a considerable role in influencing the behaviour of the uncertainty band. On the basis of these pieces of evidence, we conclude that the radar rainfall uncertainty model established under different wind conditions should be more realistic in representing the radar rainfall uncertainty. This study is only a start in incorporating synoptic regimes into rainfall uncertainty analysis, and a great deal of more effort is still needed to build a realistic and comprehensive uncertainty model for radar rainfall data. Copyright © 2014 John Wiley & Sons, Ltd