1,702 research outputs found
Calmodulin-Dependent Kinase Kinase/Calmodulin Kinase I Activity Gates Extracellular-Regulated Kinase-Dependent Long-Term Potentiation
Sequence homology at the breakpoint and clinical phenotype of mitochondrial DNA deletion syndromes
Mitochondrial DNA (mtDNA) deletions are a common cause of mitochondrial disorders. Large mtDNA deletions can lead to a broad spectrum of clinical features with different age of onset, ranging from mild mitochondrial myopathies (MM), progressive external ophthalmoplegia (PEO), and Kearns-Sayre syndrome (KSS), to severe Pearson syndrome. The aim of this study is to investigate the molecular signatures surrounding the deletion breakpoints and their association with the clinical phenotype and age at onset. MtDNA deletions in 67 patients were characterized using array comparative genomic hybridization (aCGH) followed by PCR-sequencing of the deletion junctions. Sequence homology including both perfect and imperfect short repeats flanking the deletion regions were analyzed and correlated with clinical features and patients\u27 age group. In all age groups, there was a significant increase in sequence homology flanking the deletion compared to mtDNA background. The youngest patient group (\u3c6 years old) showed a diffused pattern of deletion distribution in size and locations, with a significantly lower sequence homology flanking the deletion, and the highest percentage of deletion mutant heteroplasmy. The older age groups showed rather discrete pattern of deletions with 44% of all patients over 6 years old carrying the most common 5 kb mtDNA deletion, which was found mostly in muscle specimens (22/41). Only 15% (3/20) of the young patients (\u3c6 years old) carry the 5 kb common deletion, which is usually present in blood rather than muscle. This group of patients predominantly (16 out of 17) exhibit multisystem disorder and/or Pearson syndrome, while older patients had predominantly neuromuscular manifestations including KSS, PEO, and MM. In conclusion, sequence homology at the deletion flanking regions is a consistent feature of mtDNA deletions. Decreased levels of sequence homology and increased levels of deletion mutant heteroplasmy appear to correlate with earlier onset and more severe disease with multisystem involvement. © 2010 Sadikovic et al
Correction: Sequence homology at the breakpoint and clinical phenotype of mitochondrial DNA deletion syndromes (PLoS ONE (2010) 5:12 (e15687) DOI: 10.1371/journal.pone.0015687)
The middle initial of the third author is missing. The third author’s complete name is: Ayman W. El-Hattab. The correct citation is: Sadikovic B, Wang J, El-Hattab AW, Landsverk M, Douglas G, Brundage EK, et al. (2010) Sequence Homology at the Breakpoint and Clinical Phenotype of Mitochondrial DNA Deletion Syndromes. PLoS ONE 5(12): e15687. https://doi.org/10.1371/journal.pone.0015687
Strategies for measuring long-term control in atopic dermatitis trials: a systematic review
Background: Atopic dermatitis (AD) is a chronic inflammatory skin disease. There are no standardised methods for capturing long-term control of AD.
Objective: To identify how long-term control has been captured in published randomised controlled trials (RCTs). Resultswill initiate consensus discussions on how best to measure long-term control in the core outcome set for AD.
Methods: Systematic review of RCTs of AD treatments published between 2000 and 2013, with a follow-up period of ≥3 months, at least one outcome measure recorded at ≥3 time-points, full paper available, and published in English.
Results: 101/ 353 RCTs were eligible. Methods to capture long-term control included: repeated measurement of AD outcomes (92 RCTs; 91%), use of AD medication (29 RCTs; 28.7%); and AD flares/remissions (26 RCTs; 25.7%). Repeated measurements of AD outcomes were typically collected 3 to 5 times during a trial, but analysis methods often failed to make best use of the data. Time to first flare was most commonly for trials including flare data (21/52). Medication-use was recorded based on quantity, potency and frequency of application. Limitations: Included RCT data only
Conclusion: This review illustrates the difficulties in measuring long-term control, and points to the need for improved harmonization of outcomes
HST/ACS Emission Line Imaging of Low Redshift 3CR Radio Galaxies I: The Data
We present 19 nearby (z<0.3) 3CR radio galaxies imaged at low- and
high-excitation as part of a Cycle 15 Hubble Space Telescope snapshot survey
with the Advanced Camera for Surveys. These images consist of exposures of the
H-alpha (6563 \AA, plus [NII] contamination) and [OIII] 5007 \AA emission lines
using narrow-band linear ramp filters adjusted according to the redshift of the
target. To facilitate continuum subtraction, a single-pointing 60 s line-free
exposure was taken with a medium-band filter appropriate for the target's
redshift. We discuss the steps taken to reduce these images independently of
the automated recalibration pipeline so as to use more recent ACS flat-field
data as well as to better reject cosmic rays. We describe the method used to
produce continuum-free (pure line-emission) images, and present these images
along with qualitative descriptions of the narrow-line region morphologies we
observe. We present H-alpha+[NII] and [OIII] line fluxes from aperture
photometry, finding the values to fall expectedly on the redshift-luminosity
trend from a past HST/WFPC2 emission line study of a larger, generally higher
redshift subset of the 3CR. We also find expected trends between emission line
luminosity and total radio power, as well as a positive correlation between the
size of the emission line region and redshift. We discuss the associated
interpretation of these results, and conclude with a summary of future work
enabled by this dataset.Comment: 18 pages, 12 figures, accepted for publication in ApJ
The Atacama Cosmology Telescope: Sunyaev-Zel'dovich Selected Galaxy Clusters at 148 GHz from Three Seasons of Data
[Abridged] We present a catalog of 68 galaxy clusters, of which 19 are new
discoveries, detected via the Sunyaev-Zel'dovich effect (SZ) at 148 GHz in the
Atacama Cosmology Telescope (ACT) survey of 504 square degrees on the celestial
equator. A subsample of 48 clusters within the 270 square degree region
overlapping SDSS Stripe 82 is estimated to be 90% complete for M_500c > 4.5e14
Msun and 0.15 < z < 0.8. While matched filters are used to detect the clusters,
the sample is studied further through a "Profile Based Amplitude Analysis"
using a single filter at a fixed \theta_500 = 5.9' angular scale. This new
approach takes advantage of the "Universal Pressure Profile" (UPP) to fix the
relationship between the cluster characteristic size (R_500) and the integrated
Compton parameter (Y_500). The UPP scalings are found to be nearly identical to
an adiabatic model, while a model incorporating non-thermal pressure better
matches dynamical mass measurements and masses from the South Pole Telescope. A
high signal to noise ratio subsample of 15 ACT clusters is used to obtain
cosmological constraints. We first confirm that constraints from SZ data are
limited by uncertainty in the scaling relation parameters rather than sample
size or measurement uncertainty. We next add in seven clusters from the ACT
Southern survey, including their dynamical mass measurements based on galaxy
velocity dispersions. In combination with WMAP7 these data simultaneously
constrain the scaling relation and cosmological parameters, yielding \sigma_8 =
0.829 \pm 0.024 and \Omega_m = 0.292 \pm 0.025. The results include
marginalization over a 15% bias in dynamical mass relative to the true halo
mass. In an extension to LCDM that incorporates non-zero neutrino mass density,
we combine our data with WMAP7+BAO+Hubble constant measurements to constrain
\Sigma m_\nu < 0.29 eV (95% C. L.).Comment: 32 pages, 21 figures To appear in J. Cosmology and Astroparticle
Physic
Detection of the Power Spectrum of Cosmic Microwave Background Lensing by the Atacama Cosmology Telescope
We report the first detection of the gravitational lensing of the cosmic
microwave background through a measurement of the four-point correlation
function in the temperature maps made by the Atacama Cosmology Telescope. We
verify our detection by calculating the levels of potential contaminants and
performing a number of null tests. The resulting convergence power spectrum at
2-degree angular scales measures the amplitude of matter density fluctuations
on comoving length scales of around 100 Mpc at redshifts around 0.5 to 3. The
measured amplitude of the signal agrees with Lambda Cold Dark Matter cosmology
predictions. Since the amplitude of the convergence power spectrum scales as
the square of the amplitude of the density fluctuations, the 4-sigma detection
of the lensing signal measures the amplitude of density fluctuations to 12%.Comment: 4 pages, 4 figures, replaced title and author list with version
accepted by Physical Review Letters. Likelihood code can be downloaded from
http://bccp.lbl.gov/~sudeep/ACTLensLike.htm
Evidence for dark energy from the cosmic microwave background alone using the Atacama Cosmology Telescope lensing measurements
For the first time, measurements of the cosmic microwave background radiation
(CMB) alone favor cosmologies with dark energy over models without dark
energy at a 3.2-sigma level. We demonstrate this by combining the CMB lensing
deflection power spectrum from the Atacama Cosmology Telescope with temperature
and polarization power spectra from the Wilkinson Microwave Anisotropy Probe.
The lensing data break the geometric degeneracy of different cosmological
models with similar CMB temperature power spectra. Our CMB-only measurement of
the dark energy density confirms other measurements from
supernovae, galaxy clusters and baryon acoustic oscillations, and demonstrates
the power of CMB lensing as a new cosmological tool.Comment: 4 pages, 3 figures; replaced with version accepted by Physical Review
Letters, added sentence on models with non-standard primordial power spectr
The Atacama Cosmology Telescope: Temperature and Gravitational Lensing Power Spectrum Measurements from Three Seasons of Data
We present the temperature power spectra of the cosmic microwave background
(CMB) derived from the three seasons of data from the Atacama Cosmology
Telescope (ACT) at 148 GHz and 218 GHz, as well as the cross-frequency spectrum
between the two channels. We detect and correct for contamination due to the
Galactic cirrus in our equatorial maps. We present the results of a number of
tests for possible systematic error and conclude that any effects are not
significant compared to the statistical errors we quote. Where they overlap, we
cross-correlate the ACT and the South Pole Telescope (SPT) maps and show they
are consistent. The measurements of higher-order peaks in the CMB power
spectrum provide an additional test of the Lambda CDM cosmological model, and
help constrain extensions beyond the standard model. The small angular scale
power spectrum also provides constraining power on the Sunyaev-Zel'dovich
effects and extragalactic foregrounds. We also present a measurement of the CMB
gravitational lensing convergence power spectrum at 4.6-sigma detection
significance.Comment: 21 pages; 20 figures, Submitted to JCAP, some typos correcte
A multi-site campaign to measure solar-like oscillations in Procyon. II. Mode frequencies
We have analyzed data from a multi-site campaign to observe oscillations in
the F5 star Procyon. The data consist of high-precision velocities that we
obtained over more than three weeks with eleven telescopes. A new method for
adjusting the data weights allows us to suppress the sidelobes in the power
spectrum. Stacking the power spectrum in a so-called echelle diagram reveals
two clear ridges that we identify with even and odd values of the angular
degree (l=0 and 2, and l=1 and 3, respectively). We interpret a strong, narrow
peak at 446 muHz that lies close to the l=1 ridge as a mode with mixed
character. We show that the frequencies of the ridge centroids and their
separations are useful diagnostics for asteroseismology. In particular,
variations in the large separation appear to indicate a glitch in the
sound-speed profile at an acoustic depth of about 1000 s. We list frequencies
for 55 modes extracted from the data spanning 20 radial orders, a range
comparable to the best solar data, which will provide valuable constraints for
theoretical models. A preliminary comparison with published models shows that
the offset between observed and calculated frequencies for the radial modes is
very different for Procyon than for the Sun and other cool stars. We find the
mean lifetime of the modes in Procyon to be 1.29 +0.55/-0.49 days, which is
significantly shorter than the 2-4 days seen in the Sun.Comment: accepted for publication in Ap
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