822 research outputs found
Development of advanced digital techniques for data acquisition processing and communication Interim scientific report
Image correlation and computerized simulation applied to data acquisition and imaging technique
PCM telemetry data compression study, phase II Quarterly report, 25 Nov. 1965 - 25 Feb. 1966
Model analyses and computer simulations used in data compression study for improved pulse code modulation telemetry link
The development of advanced digital techniques for data acquisition processing and communication Interim scientific report
Digital techniques for characterization of image sources, second order interpolation, sensitivity of compressed pictures to error, and simulation of mapping technique
A Recessive Mutation Resulting in a Disabling Amino Acid Substitution (T194R) in the LHX3 Homeodomain Causes Combined Pituitary Hormone Deficiency
Background/Aims: Recessive mutations in the LHX3 homeodomain transcription factor gene are associated with developmental disorders affecting the pituitary and nervous system. We describe pediatric patients with combined pituitary hormone deficiency (CPHD) who harbor a novel mutation in LHX3. Methods: Two female siblings from related parents were examined. Both patients had neonatal complications. The index patient had CPHD featuring deficiencies of GH, LH, FSH, PRL, and TSH, with later onset of ACTH deficiency. She also had a hypoplastic anterior pituitary, respiratory distress, hearing impairment, and limited neck rotation. The LHX3 gene was sequenced and the biochemical properties of the predicted altered proteins were characterized. Results: A novel homozygous mutation predicted to change amino acid 194 from threonine to arginine (T194R) was detected in both patients. This amino acid is conserved in the DNA-binding homeodomain. Computer modeling predicted that the T194R change would alter the homeodomain structure. The T194R protein did not bind tested LHX3 DNA recognition sites and did not activate the a-glycoprotein and PRL target genes. Conclusion: The T194R mutation affects a critical residue in the LHX3 protein. This study extends our understanding of the phenotypic features, molecular mechanism, and developmental course associated with mutations in the LHX3 gene. copyright (C) 2012 S. Karger AG, Base
PCM telemetry data compression study, phase 1 Final report, 15 Sep. 1964 - 15 Aug. 1965
Pulse Code Modulation /PCM/ telemetry data compression study using S-6 Explorer XVII DAT
A Proto-Galaxy Candidate at z=2.7 Discovered by Its Young Stellar Population
A protogalaxy candidate at z=2.72 has been discovered serendipitously by the
CNOC cluster redshift survey. The candidate is an extremely luminous (V=20.5
mag, absolute mag -26) and well resolved disk-like galaxy. The redshift is
identified from a dozen strong UV absorption lines. No emission lines are found
between 1000 and 2000A (rest), including Ly alpha. The photometric data fit the
spectral energy distributions of a stellar population from 400 million years to
an arbitrarily young age, dependent on the amount of dust extinction. However,
the presence of a strong P-Cygni profile in CIV~indicates that a very
substantial component of the stellar population must be younger than ~ 10 Myr.
We interpret this object as an early-type galaxy observed within about 100
million years of the initial burst of star formation which created most of its
stellar mass. Because of the resolved, regular, and smooth nature of the
object, it is unlikely that the high luminosity is due to gravitational
lensing.Comment: 31 page, Latex file with 9 encapsulated figures, requiring aasppt.sty
and epsf.sty (included). Full uuencoded ps file available from:
http://manaslu.astro.utoronto.ca/~carlberg/cnoc/general.html Accepted by
Astronomical Journal, in press, May 199
The structural properties and star formation history of Leo T from deep LBT photometry
We present deep, wide-field g and r photometry of the transition type dwarf
galaxy Leo T, obtained with the blue arm of the Large Binocular Telescope. The
data confirm the presence of both very young (5
Gyr) stars. We study the structural properties of the old and young stellar
populations by preferentially selecting either population based on their color
and magnitude. The young population is significantly more concentrated than the
old population, with half-light radii of 104+-8 and 148+-16 pc respectively,
and their centers are slightly offset. Approximately 10% of the total stellar
mass is estimated to be represented by the young stellar population. Comparison
of the color-magnitude diagram (CMD) with theoretical isochrones as well as
numerical CMD-fitting suggest that star formation began over 10 Gyr ago and
continued in recent times until at least a few hundred Myr ago. The CMD-fitting
results are indicative of two distinct star formation bursts, with a quiescent
period around 3 Gyr ago, albeit at low significance. The results are consistent
with no metallicity evolution and [Fe/H] ~ -1.5 over the entire age of the
system. Finally, the data show little if any sign of tidal distortion of Leo T.Comment: 8 pages, 9 figures, some small textual changes, accepted for
publication in the Astrophysical Journa
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