509 research outputs found
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Accessible Creativity with a Comic Spin
Creativity and humour allow people to be expressive and to address topics which they might otherwise avoid or find deeply uncomfortable. One such way to express these sentiments is via comics. Comics have a highly-visual format with relatively little language.They therefore offer a promising opportunity for people who experience challenges with language to express creativity and humour. Most comic tools, however, are not accessible to people with language impairments. In this paper we describe ComicSpin, a comic app designed for people with aphasia. ComicSpin builds upon the literature on supporting creativity by constraining the creative space. We report both the design process and the results of a creative workshop where people with aphasia used ComicSpin. Participants were not only successful in using the app,but were able to create a range of narrative ,humorous and subversive comics
Effects of Non-Circular Motions on Azimuthal Color Gradients
Assuming that density waves trigger star formation, and that young stars
preserve the velocity components of the molecular gas where they are born, we
analyze the effects that non-circular gas orbits have on color gradients across
spiral arms. We try two approaches, one involving semi-analytical solutions for
spiral shocks, and another with magnetohydrodynamic (MHD) numerical simulation
data. We find that, if non-circular motions are ignored, the comparison between
observed color gradients and stellar population synthesis models would in
principle yield pattern speed values that are systematically too high for
regions inside corotation, with the difference between the real and the
measured pattern speeds increasing with decreasing radius. On the other hand,
image processing and pixel averaging result in systematically lower measured
spiral pattern speed values, regardless of the kinematics of stellar orbits.
The net effect is that roughly the correct pattern speeds are recovered,
although the trend of higher measured at lower radii (as expected
when non-circular motions exist but are neglected) should still be observed. We
examine the Martinez-Garcia et al. (2009) photometric data and confirm that
this is indeed the case. The comparison of the size of the systematic pattern
speed offset in the data with the predictions of the semi-analytical and MHD
models corroborates that spirals are more likely to end at Outer Lindblad
Resonance, as these authors had already found.Comment: 32 pages, 15 figures, accepted to Ap
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Comic Spin: A Comic Creation Tool Enabling Self-Expression for People with Aphasia
Comics, with their highly visual format, offer a promising opportunity for people who experience challenges with language to express humour and emotion. However, comic creation tools are not designed to be accessible to people with language impairments such as aphasia. We report the design and exploration of Comic Spin , an app for people with aphasia that supports the creation of comic strips by constraining the creative space. We explored the use of Comic Spin in two studies involving creative workshops. Findings showed that people were able to use Comic Spin successfully to create a range of narrative, humorous and subversive comic strips, and that these enabled people to self-express in ways that went beyond the content of the comic strips themselves
The dark matter halo shape of edge-on disk galaxies - I. HI observations
This is the first paper of a series in which we will attempt to put
constraints on the flattening of dark halos in disk galaxies. We observe for
this purpose the HI in edge-on galaxies, where it is in principle possible to
measure the force field in the halo vertically and radially from gas layer
flaring and rotation curve decomposition respectively. In this paper, we define
a sample of 8 HI-rich late-type galaxies suitable for this purpose and present
the HI observations.Comment: Accepted for publication by Astronomy & Astrophysics. For a higher
resolution version see
http://www.astro.rug.nl/~vdkruit/jea3/homepage/12565.pd
Specific Etiologies Associated With the Multiple Organ Dysfunction Syndrome in Children: Part 2
To describe a number of conditions and therapies associated with multiple organ dysfunction syndrome (MODS) presented as part of the Eunice Kennedy Shriver National Institute of Child Health and Human Development MODS Workshop (March 26–27, 2015). In addition, the relationship between burn injuries and MODS is also included although it was not discussed at the Workshop
The role of feedback in shaping the structure of the interstellar medium
We present an analysis of the role of feedback in shaping the neutral hydrogen (H I) content of simulated disc galaxies. For our analysis, we have used two realizations of two separate Milky Way-like (similar to L star) discs - one employing a conservative feedback scheme (McMaster Unbiased Galaxy Survey), the other significantly more energetic [Making Galaxies In a Cosmological Context (MaGICC)]. To quantify the impact of these schemes, we generate zeroth moment (surface density) maps of the inferred H I distribution; construct power spectra associated with the underlying structure of the simulated cold interstellar medium, in addition to their radial surface density and velocity dispersion profiles. Our results are compared with a parallel, self-consistent, analysis of empirical data from The H I Nearby Galaxy Survey (THINGS). Single power-law fits (P proportional to k(gamma)) to the power spectra of the stronger feedback (MaGICC) runs (over spatial scales corresponding to similar to 0.5 to similar to 20 kpc) result in slopes consistent with those seen in the THINGS sample (gamma similar to -2.5). The weaker feedback (MUGS) runs exhibit shallower power-law slopes (gamma similar to -1.2). The power spectra of the MaGICC simulations are more consistent though with a two-component fit, with a flatter distribution of power on larger scales (i.e. gamma similar to -1.4 for scales in excess of similar to 2 kpc) and a steeper slope on scales below similar to 1 kpc (gamma similar to -5), qualitatively consistent with empirical claims, as well as our earlier work on dwarf discs. The radial H I surface density profiles of the MaGICC discs show a clear exponential behaviour, while those of the MUGS suite are essentially flat; both behaviours are encountered in nature, although the THINGS sample is more consistent with our stronger (MaGICC) feedback runs
Tracing spiral density waves in M81
We use SPITZER IRAC 3.6 and 4.5micron near infrared data from the Spitzer
Infrared Nearby Galaxies Survey (SINGS), optical B, V and I and 2MASS Ks band
data to produce mass surface density maps of M81. The IRAC 3.6 and 4.5micron
data, whilst dominated by emission from old stellar populations, is corrected
for small-scale contamination by young stars and PAH emission. The I band data
are used to produce a mass surface density map by a B-V colour-correction,
following the method of Bell and de Jong. We fit a bulge and exponential disc
to each mass map, and subtract these components to reveal the non-axisymmetric
mass surface density. From the residual mass maps we are able to extract the
amplitude and phase of the density wave, using azimuthal profiles. The response
of the gas is observed via dust emission in the 8micron IRAC band, allowing a
comparison between the phase of the stellar density wave and gas shock. The
relationship between this angular offset and radius suggests that the spiral
structure is reasonably long lived and allows the position of corotation to be
determined.Comment: 15 pages, 17 figures, accepted for publication in MNRA
Spiral-Induced Star Formation in the Outer Disks of Galaxies
The outer regions of galactic disks have received increased attention since
ultraviolet observations with GALEX demonstrated that nearly 30% of galaxies
have UV emission beyond their optical extents, indicating star formation
activity. These galaxies have been termed extended UV (XUV) disks. Here, we
address whether these observations contradict the gas surface density threshold
for star formation inferred from Halpha radial profiles of galaxies. We run
smoothed particle hydrodynamics simulations of isolated disk galaxies with
fiducial star formation prescriptions and show that over-densities owing to the
presence of spiral structure can induce star formation in extended gas disks.
For direct comparison with observations, we use the 3-D radiative transfer code
Sunrise to create simulated FUV and K_s band images. We find that galaxies
classified as Type I XUV disks are a natural consequence of spiral patterns,
but we are unable to reproduce Type II XUV disks. We also compare our results
to studies of the Kennicutt-Schmidt relation in outer disks.Comment: Published in Ap
Numerical modelling of Auriga's Wheel - a new ring galaxy
We model the formation of Auriga's Wheel - a recently discovered collisional
ring galaxy. Auriga's Wheel has a number of interesting features including a
bridge of stars linking the neighbouring elliptical to the ring galaxy, and
evidence for components of expansion and rotation within the ring. Using
N-body/SPH modelling, we study collisions between an elliptical galaxy and a
late-type disk galaxy. A near direct collision, with a mildy inclined disk, is
found to reasonably reproduce the general system morphology ~50 Myr following
the collision. The collision must have a relatively low velocity (initially
~150 km s^{-1}) in order to form the observed bridge, and simultaneously match
the galaxies separation. Our best-match model suggests the total disk galaxy is
~5 times more massive than the elliptical. We find that the velocity of
expansion of the ring is sensitive to the mass of the elliptical, while
insensitive to the encounter velocity. We evolve our simulation beyond the
current epoch to study the future destiny of the galaxy pair. In our model, the
nucleus moves further away from the plane of the ring in the direction of the
stellar bridge. The nucleus eventually merges with the elliptical galaxy ~100
Myr after the present time. The ring continues to expand for ~200 Myr before
collapsing back. The low initial relative velocity of the two galaxies will
eventually result in a complete merger.Comment: Accepted to MNRAS, March 9th, 2012. 17 pages, 16 figures, no table
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