835 research outputs found
National Patient Safety Initiatives: Moving beyond What Is Necessary
Ilan and Donchin have compared Israel and Canada's experiences in setting a national patient safety agenda. We broaden this comparison to include the U.S. experience, and suggest that there are three additional key steps which will be important in any national patient safety agenda, and which Israel in particular should consider. These are 1) using health information technology (HIT) to directly improve patient safety, 2) dissemination and broad use of checklists, and 3) measuring patient safety over time at the national level. Especially because of its already substantial commitment to HIT and well-developed HIT sector, Israel has a major opportunity to move forward rapidly in this area and to achieve broad impact on the safety front. This is a commentary on http://www.ijhpr.org/content/1/1/19
Strikes and Lockouts in Germany and Under Federal Legislation in the United States: A Comparative Analysis
The Disk Mass project; science case for a new PMAS IFU module
We present our Disk Mass project as the main science case for building a new
fiber IFU-module for the PMAS spectrograph, currently mounted at the Cassegrain
focus of the 3.5m telescope on Calar Alto. Compared to traditional long-slit
observations, the large light collecting power of 2-dimensional Integral Field
Units dramatically improves the prospects for performing spectroscopy on
extended low surface brightness objects with high spectral resolution. This
enables us to measure stellar velocity dispersions in the outer disk of normal
spiral galaxies. We describe some results from a PMAS pilot study using the
existing lenslet array, and provide a basic description of the new fiber
IFU-module for PMAS.Comment: 4 pages, 5 figures. Refereed proceeding for the `Euro3D Science
Workshop'. Contains updated layout of PPAK fibers, and improved M/L value for
N398
The DiskMass Survey. VIII. On the Relationship Between Disk Stability and Star Formation
We study the relationship between the stability level of late-type galaxy
disks and their star-formation activity using integral-field gaseous and
stellar kinematic data. Specifically, we compare the two-component (gas+stars)
stability parameter from Romeo & Wiegert (Q_RW), incorporating stellar
kinematic data for the first time, and the star-formation rate estimated from
21cm continuum emission. We determine the stability level of each disk
probabilistically using a Bayesian analysis of our data and a simple dynamical
model. Our method incorporates the shape of the stellar velocity ellipsoid
(SVE) and yields robust SVE measurements for over 90% of our sample. Averaging
over this subsample, we find a meridional shape of sigma_z/sigma_R =
0.51^{+0.36}_{-0.25} for the SVE and, at 1.5 disk scale lengths, a stability
parameter of Q_RW = 2.0 +/- 0.9. We also find that the disk-averaged
star-formation-rate surface density (Sigma-dot_e,*) is correlated with the
disk-averaged gas and stellar mass surface densities (Sigma_e,g and Sigma_e,*)
and anti-correlated with Q_RW. We show that an anti-correlation between
Sigma-dot_e,* and Q_RW can be predicted using empirical scaling relations, such
that this outcome is consistent with well-established statistical properties of
star-forming galaxies. Interestingly, Sigma-dot_e,* is not correlated with the
gas-only or star-only Toomre parameters, demonstrating the merit of calculating
a multi-component stability parameter when comparing to star-formation
activity. Finally, our results are consistent with the Ostriker et al. model of
self-regulated star-formation, which predicts
Sigma-dot_e,*/Sigma_e,g/sqrt(Sigma_e,*). Based on this and other theoretical
expectations, we discuss the possibility of a physical link between disk
stability level and star-formation rate in light of our empirical results.Comment: Accepted for publication in ApJ. 15 pages, 6 figures, 2 tables. An
electronic version of Table 1 is available by request, or at
http://www.astro.rug.nl/~westfall/research/dmVIII_table1.tx
The DiskMass Survey. X. Radio synthesis imaging of spiral galaxies
We present results from 21 cm radio synthesis imaging of 28 spiral galaxies
from the DiskMass Survey obtained with the VLA, WSRT, and GMRT facilities. We
detail the observations and data reduction procedures and present a brief
analysis of the radio data. We construct 21 cm continuum images, global HI
emission-line profiles, column-density maps, velocity fields, and
position-velocity diagrams. From these we determine star formation rates
(SFRs), HI line widths, total HI masses, rotation curves, and
azimuthally-averaged radial HI column-density profiles. All galaxies have an HI
disk that extends beyond the readily observable stellar disk, with an average
ratio and scatter of R_{HI}/R_{25}=1.35+/-0.22, and a majority of the galaxies
appear to have a warped HI disk. A tight correlation exists between total HI
mass and HI diameter, with the largest disks having a slightly lower average
column density. Galaxies with relatively large HI disks tend to exhibit an
enhanced stellar velocity dispersion at larger radii, suggesting the influence
of the gas disk on the stellar dynamics in the outer regions of disk galaxies.
We find a striking similarity among the radial HI surface density profiles,
where the average, normalized radial profile of the late-type spirals is
described surprisingly well with a Gaussian profile. These results can be used
to estimate HI surface density profiles in galaxies that only have a total HI
flux measurement. We compare our 21 cm radio continuum luminosities with 60
micron luminosities from IRAS observations for a subsample of 15 galaxies and
find that these follow a tight radio-infrared relation, with a hint of a
deviation from this relation at low luminosities. We also find a strong
correlation between the average SFR surface density and the K-band surface
brightness of the stellar disk.Comment: 22 pages + Appendix, 16 figures + Atlas, 5 tables. Accepted for
publication in Astronomy & Astrophysic
SparsePak: A Formatted Fiber Field-Unit for The WIYN Telescope Bench Spectrograph. II. On-Sky Performance
We present a performance analysis of SparsePak and the WIYN Bench
Spectrograph for precision studies of stellar and ionized gas kinematics of
external galaxies. We focus on spectrograph configurations with echelle and
low-order gratings yielding spectral resolutions of ~10000 between 500-900nm.
These configurations are of general relevance to the spectrograph performance.
Benchmarks include spectral resolution, sampling, vignetting, scattered light,
and an estimate of the system absolute throughput. Comparisons are made to
other, existing, fiber feeds on the WIYN Bench Spectrograph. Vignetting and
relative throughput are found to agree with a geometric model of the optical
system. An aperture-correction protocol for spectrophotometric standard-star
calibrations has been established using independent WIYN imaging data and the
unique capabilities of the SparsePak fiber array. The WIYN
point-spread-function is well-fit by a Moffat profile with a constant power-law
outer slope of index -4.4. We use SparsePak commissioning data to debunk a
long-standing myth concerning sky-subtraction with fibers: By properly treating
the multi-fiber data as a ``long-slit'' it is possible to achieve precision sky
subtraction with a signal-to-noise performance as good or better than
conventional long-slit spectroscopy. No beam-switching is required, and hence
the method is efficient. Finally, we give several examples of science
measurements which SparsePak now makes routine. These include H
velocity fields of low surface-brightness disks, gas and stellar
velocity-fields of nearly face-on disks, and stellar absorption-line profiles
of galaxy disks at spectral resolutions of ~24,000.Comment: To appear in ApJSupp (Feb 2005); 19 pages text; 7 tables; 27 figures
(embedded); high-resolution version at
http://www.astro.wisc.edu/~mab/publications/spkII_pre.pd
Three Tributaries, Exploring the Reformed, Baptist, and Catholic Branches: A Review of The Church\u27s Book
If our conversations about the Bible, its meaning, and its authority seem always to prove fruitless, perhaps this is a better place to start.
Posting about the book The Church\u27s Book from In All Things - an online journal for critical reflection on faith, culture, art, and every ordinary-yet-graced square inch of God’s creation.
https://inallthings.org/three-tributaries-exploring-the-reformed-baptist-and-catholic-branches-a-review-of-the-churchs-book
Forcing Incidents of Marriage on Unmarried Cohabitants: The American Law Institute\u27s Principles of Family Dissolution
Forcing Incidents of Marriage on Unmarried Cohabitants: The American Law Institute\u27s Principles of Family Dissolution
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