90 research outputs found
Does reperfusion injury still cause significant mortality after lung transplantation?
ObjectivesSevere reperfusion injury after lung transplantation has mortality rates approaching 40%. The purpose of this investigation was to identify whether our improved 1-year survival after lung transplantation is related to a change in reperfusion injury.MethodsWe reported in March 2000 that early institution of extracorporeal membrane oxygenation can improve lung transplantation survival. The records of consecutive lung transplant recipients from 1990 to March 2000 (early era, n = 136) were compared with those of recipients from March 2000 to August 2006 (current era, n = 155). Reperfusion injury was defined by an oxygenation index of greater than 7 (where oxygenation index = [Percentage inspired oxygen] × [Mean airway pressure]/[Partial pressure of oxygen]). Risk factors for reperfusion injury, treatment of reperfusion injury, and 30-day mortality were compared between eras by using χ2, Fisher's, or Student's t tests where appropriate.ResultsAlthough the incidence of reperfusion injury did not change between the eras, 30-day mortality after lung transplantation improved from 11.8% in the early era to 3.9% in the current era (P = .003). In patients without reperfusion injury, mortality was low in both eras. Patients with reperfusion injury had less severe reperfusion injury (P = .01) and less mortality in the current era (11.4% vs 38.2%, P = .01). Primary pulmonary hypertension was more common in the early era (10% [14/136] vs 3.2% [5/155], P = .02). Graft ischemic time increased from 223.3 ± 78.5 to 286.32 ± 88.3 minutes in the current era (P = .0001). The mortality of patients with reperfusion injury requiring extracorporeal membrane oxygenation improved in the current era (80.0% [8/10] vs 25.0% [3/12], P = .01).ConclusionImproved early survival after lung transplantation is due to less severe reperfusion injury, as well as improvements in survival with extracorporeal membrane oxygenation
The DEEP Groth Strip Galaxy Redshift Survey. III. Redshift Catalog and Properties of Galaxies
The Deep Extragalactic Evolutionary Probe (DEEP) is a series of spectroscopic
surveys of faint galaxies, targeted at the properties and clustering of
galaxies at redshifts z ~ 1. We present the redshift catalog of the DEEP 1 GSS
pilot phase of this project, a Keck/LRIS survey in the HST/WFPC2 Groth Survey
Strip. The redshift catalog and data, including reduced spectra, are publicly
available through a Web-accessible database. The catalog contains 658 secure
galaxy redshifts with a median z=0.65, and shows large-scale structure walls to
z = 1. We find a bimodal distribution in the galaxy color-magnitude diagram
which persists to z = 1. A similar color division has been seen locally by the
SDSS and to z ~ 1 by COMBO-17. For red galaxies, we find a reddening of only
0.11 mag from z ~ 0.8 to now, about half the color evolution measured by
COMBO-17. We measure structural properties of the galaxies from the HST
imaging, and find that the color division corresponds generally to a structural
division. Most red galaxies, ~ 75%, are centrally concentrated, with a red
bulge or spheroid, while blue galaxies usually have exponential profiles.
However, there are two subclasses of red galaxies that are not bulge-dominated:
edge-on disks and a second category which we term diffuse red galaxies
(DIFRGs). The distant edge-on disks are similar in appearance and frequency to
those at low redshift, but analogs of DIFRGs are rare among local red galaxies.
DIFRGs have significant emission lines, indicating that they are reddened
mainly by dust rather than age. The DIFRGs in our sample are all at z>0.64,
suggesting that DIFRGs are more prevalent at high redshifts; they may be
related to the dusty or irregular extremely red objects (EROs) beyond z>1.2
that have been found in deep K-selected surveys. (abridged)Comment: ApJ in press. 24 pages, 17 figures (12 color). The DEEP public
database is available at http://saci.ucolick.org
The DEEP Groth Strip Survey. I. The Sample
The Deep Extragalactic Exploratory Probe (DEEP) is a multi-phase research
program dedicated to the study of the formation and evolution of galaxies and
of large scale structure in the distant Universe. This paper describes the
first five-year phase, denoted DEEP1. A series of ten DEEP1 papers will discuss
a range of scientific topics (e.g., the study of photometric and spectral
properties of a general distant galaxy survey, the evolution observed in galaxy
populations of varied morphologies). The observational basis for these studies
is the Groth Survey Strip field, a 127 square arcminute region which has been
observed with the Hubble Space Telescope in both broad I-band and V-band
optical filters and with the Low Resolution Imaging Spectrograph on the Keck
Telescopes. Catalogs of photometric and structural parameters have been
constructed for 11,547 galaxies and stars at magnitudes brighter than 29, and
spectroscopy has been conducted for a magnitude-color weighted subsample of 818
objects. We evaluate three independent techniques for constructing an imaging
catalog for the field from the HST data, and discuss the depth and sampling of
the resultant catalogs. The selection of the spectroscopic subsample is
discussed, and we describe the multifaceted approach taken to prioritizing
objects of interest for a variety of scientific subprograms. A series of Monte
Carlo simulations then demonstrates that the spectroscopic subsample can be
adequately modeled as a simple function of magnitude and color cuts in the
imaging catalog.Comment: ApJS accepted, 15 pages, 12 figures. Version with higher-quality
figures available at http://astronomy.nmsu.edu/nicol
The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III
The Sloan Digital Sky Survey (SDSS) started a new phase in August 2008, with
new instrumentation and new surveys focused on Galactic structure and chemical
evolution, measurements of the baryon oscillation feature in the clustering of
galaxies and the quasar Ly alpha forest, and a radial velocity search for
planets around ~8000 stars. This paper describes the first data release of
SDSS-III (and the eighth counting from the beginning of the SDSS). The release
includes five-band imaging of roughly 5200 deg^2 in the Southern Galactic Cap,
bringing the total footprint of the SDSS imaging to 14,555 deg^2, or over a
third of the Celestial Sphere. All the imaging data have been reprocessed with
an improved sky-subtraction algorithm and a final, self-consistent photometric
recalibration and flat-field determination. This release also includes all data
from the second phase of the Sloan Extension for Galactic Understanding and
Evolution (SEGUE-2), consisting of spectroscopy of approximately 118,000 stars
at both high and low Galactic latitudes. All the more than half a million
stellar spectra obtained with the SDSS spectrograph have been reprocessed
through an improved stellar parameters pipeline, which has better determination
of metallicity for high metallicity stars.Comment: Astrophysical Journal Supplements, in press (minor updates from
submitted version
Genome size variation in diploid and tetraploid wild wheats
Low but significant intraspecific genome size variations were found in diploid and tetraploid wild wheats. This limited variation is not correlated with geographical and climate variables. It can be concluded that the genome size of Triticum species is generally stable, despite of the presence of many potentially active retroelements
CFHTLenS: Improving the quality of photometric redshifts with precision photometry
Here we present the results of various approaches to measure accurate colours
and photometric redshifts (photo-z's) from wide-field imaging data. We use data
from the Canada-France-Hawaii-Telescope Legacy Survey (CFHTLS) which have been
re- processed by the CFHT Lensing Survey (CFHTLenS) team in order to carry out
a number of weak gravitational lensing studies. An emphasis is put on the
correction of systematic effects in the photo-z's arising from the different
Point Spread Functions (PSF) in the five optical bands. Different ways of
correcting these effects are discussed and the resulting photo-z accuracies are
quantified by comparing the photo-z's to large spectroscopic redshift (spec-z)
data sets. Careful homogenisation of the PSF between bands leads to increased
overall accuracy of photo-z's. The gain is particularly pronounced at fainter
magnitudes where galaxies are smaller and flux measurements are affected more
by PSF-effects. We also study possible re- calibrations of the photometric
zeropoints (ZPs) with the help of galaxies with known spec-z's. We find that if
PSF-effects are properly taken into account, a re-calibration of the ZPs
becomes much less important suggesting that previous such re-calibrations
described in the literature could in fact be mostly corrections for PSF-effects
rather than corrections for real inaccuracies in the ZPs. The implications of
this finding for future surveys like KiDS, DES, LSST, or Euclid are mixed. On
the one hand, ZP re-calibrations with spec-z's might not be as accurate as
previously thought. On the other hand, careful PSF homogenisation might provide
a way out and yield accurate, homogeneous photometry without the need for full
spectroscopic coverage. This is the first paper in a series describing the
technical aspects of CFHTLenS. (abridged)Comment: 15 pages, 10 figures, accepted by MNRAS, minor revision
Direct Regulation of Striated Muscle Myosins by Nitric Oxide and Endogenous Nitrosothiols
, both through activation of guanylyl cyclase and through modification of cysteines in proteins to yield S-nitrosothiols. While NO affects the contractile apparatus directly, the identities of the target myofibrillar proteins remain unknown. Here we report that nitrogen oxides directly regulate striated muscle myosins..These data show that nitrosylation signaling acts as a molecular “gear shift” for myosin—an altogether novel mechanism by which striated muscle and cellular biomechanics may be regulated
RNA Methylation by the MIS Complex Regulates a Cell Fate Decision in Yeast
For the yeast Saccharomyces cerevisiae, nutrient limitation is a key developmental signal causing diploid cells to switch from yeast-form budding to either foraging pseudohyphal (PH) growth or meiosis and sporulation. Prolonged starvation leads to lineage restriction, such that cells exiting meiotic prophase are committed to complete sporulation even if nutrients are restored. Here, we have identified an earlier commitment point in the starvation program. After this point, cells, returned to nutrient-rich medium, entered a form of synchronous PH development that was morphologically and genetically indistinguishable from starvation-induced PH growth. We show that lineage restriction during this time was, in part, dependent on the mRNA methyltransferase activity of Ime4, which played separable roles in meiotic induction and suppression of the PH program. Normal levels of meiotic mRNA methylation required the catalytic domain of Ime4, as well as two meiotic proteins, Mum2 and Slz1, which interacted and co-immunoprecipitated with Ime4. This MIS complex (Mum2, Ime4, and Slz1) functioned in both starvation pathways. Together, our results support the notion that the yeast starvation response is an extended process that progressively restricts cell fate and reveal a broad role of post-transcriptional RNA methylation in these decisions
Erratum: “The eighth data release of the Sloan Digital Sky Survey: first data from SDSS-III” (2011, ApJS, 193, 29)
Section 3.5 of Aihara et al. (2011) described various sources of systematic error in the astrometry of the imaging data of the Sloan Digital Sky Survey (SDSS). In addition to these sources of error, there is an additional and more serious error, which introduces a large systematic shift in the astrometry over a large area around the north celestial pole. The region has irregular boundaries but in places extends as far south as declination δ ≈ 41◦. The sense of the shift is that the positions of all sources in the affected area are offset by roughly 250 mas in a northwest direction. We have updated the SDSS online documentation to reflect these errors, and to provide detailed quality information for each SDSS field
SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems
Building on the legacy of the Sloan Digital Sky Survey (SDSS-I and II),
SDSS-III is a program of four spectroscopic surveys on three scientific themes:
dark energy and cosmological parameters, the history and structure of the Milky
Way, and the population of giant planets around other stars. In keeping with
SDSS tradition, SDSS-III will provide regular public releases of all its data,
beginning with SDSS DR8 (which occurred in Jan 2011). This paper presents an
overview of the four SDSS-III surveys. BOSS will measure redshifts of 1.5
million massive galaxies and Lya forest spectra of 150,000 quasars, using the
BAO feature of large scale structure to obtain percent-level determinations of
the distance scale and Hubble expansion rate at z<0.7 and at z~2.5. SEGUE-2,
which is now completed, measured medium-resolution (R=1800) optical spectra of
118,000 stars in a variety of target categories, probing chemical evolution,
stellar kinematics and substructure, and the mass profile of the dark matter
halo from the solar neighborhood to distances of 100 kpc. APOGEE will obtain
high-resolution (R~30,000), high signal-to-noise (S/N>100 per resolution
element), H-band (1.51-1.70 micron) spectra of 10^5 evolved, late-type stars,
measuring separate abundances for ~15 elements per star and creating the first
high-precision spectroscopic survey of all Galactic stellar populations (bulge,
bar, disks, halo) with a uniform set of stellar tracers and spectral
diagnostics. MARVELS will monitor radial velocities of more than 8000 FGK stars
with the sensitivity and cadence (10-40 m/s, ~24 visits per star) needed to
detect giant planets with periods up to two years, providing an unprecedented
data set for understanding the formation and dynamical evolution of giant
planet systems. (Abridged)Comment: Revised to version published in The Astronomical Journa
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