749 research outputs found
A genome-wide association study suggests that a locus within the ataxin 2 binding protein 1 gene is associated with hand osteoarthritis: The Treat-OA consortium
To identify the susceptibility gene in hand osteoarthritis (OA) the authors used a two-stage approach genomewide association study using two discovery samples (the TwinsUK cohort and the Rotterdam discovery subset; a total of 1804 subjects) and four replication samples (the Chingford Study, the Chuvasha Skeletal Aging Study, the Rotterdam replication subset and the Genetics, Arthrosis, and Progression (GARP) Study; a total of 3266 people). Five single-nucleotide polymorphisms (SNPs) had a likelihood of association with hand OA in the discovery stage and one of them (rs716508), was successfully confirmed in the replication stage (meta-analysis p = 1.81Ă10-5). The C allele conferred a reduced risk of 33% to 41% using a case-control definition. The SNP is located in intron 1 of the A2BP1 gene. This study also found that the same allele of the SNP significantly reduced bone density at both the hip and spine (p<0.01), suggesting the potential mechanism of the gene in hand OA might be via effects on subchondral bone. The authors' findings provide a potential new insight into genetic mechanisms in the development of hand OA
NOMINAL VALUES FOR SELECTED SOLAR AND PLANETARY QUANTITIES: IAU 2015 RESOLUTION B3
In this brief communication we provide the rationale for and the outcome of the International Astronomical Union (IAU) resolution vote at the XXIXth General Assembly in Honolulu, Hawaii, in 2015, on recommended nominal conversion constants for selected solar and planetary properties. The problem addressed by the resolution is a lack of established conversion constants between solar and planetary values and SI units: a missing standard has caused a proliferation of solar values (e.g., solar radius, solar irradiance, solar luminosity, solar effective temperature, and solar mass parameter) in the literature, with cited solar values typically based on best estimates at the time of paper writing. As precision of observations increases, a set of consistent values becomes increasingly important. To address this, an IAU Working Group on Nominal Units for Stellar and Planetary Astronomy formed in 2011, uniting experts from the solar, stellar, planetary, exoplanetary, and fundamental astronomy, as well as from general standards ïŹelds to converge on optimal values for nominal conversion constants. The effort resulted in the IAU 2015 Resolution B3, passed at the IAU General Assembly by a large majority. The resolution recommends the use of nominal solar and planetary values, which are by deïŹnition exact and are expressed in SI units. These nominal
values should be understood as conversion factors only, not as the true solar/planetary properties or current best estimates. Authors and journal editors are urged to join in using the standard values set forth by this resolution in
future work and publications to help minimize further confusion
Hardware Validation Test of the Advanced Plant Habitat
An automated plant growth facility for conducting plant research supporting space biology and food production project on the International Space Station (ISS)
Wheat Crop in the Advanced Plant Habitat of the International Space Station
Plants are grown in the Science Carrier(SC)of the APH,(0.2m2instrumented)root module
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
The Seventh Data Release of the Sloan Digital Sky Survey
This paper describes the Seventh Data Release of the Sloan Digital Sky Survey
(SDSS), marking the completion of the original goals of the SDSS and the end of
the phase known as SDSS-II. It includes 11663 deg^2 of imaging data, with most
of the roughly 2000 deg^2 increment over the previous data release lying in
regions of low Galactic latitude. The catalog contains five-band photometry for
357 million distinct objects. The survey also includes repeat photometry over
250 deg^2 along the Celestial Equator in the Southern Galactic Cap. A
coaddition of these data goes roughly two magnitudes fainter than the main
survey. The spectroscopy is now complete over a contiguous area of 7500 deg^2
in the Northern Galactic Cap, closing the gap that was present in previous data
releases. There are over 1.6 million spectra in total, including 930,000
galaxies, 120,000 quasars, and 460,000 stars. The data release includes
improved stellar photometry at low Galactic latitude. The astrometry has all
been recalibrated with the second version of the USNO CCD Astrograph Catalog
(UCAC-2), reducing the rms statistical errors at the bright end to 45
milli-arcseconds per coordinate. A systematic error in bright galaxy photometr
is less severe than previously reported for the majority of galaxies. Finally,
we describe a series of improvements to the spectroscopic reductions, including
better flat-fielding and improved wavelength calibration at the blue end,
better processing of objects with extremely strong narrow emission lines, and
an improved determination of stellar metallicities. (Abridged)Comment: 20 pages, 10 embedded figures. Accepted to ApJS after minor
correction
The Fifth Data Release of the Sloan Digital Sky Survey
This paper describes the Fifth Data Release (DR5) of the Sloan Digital Sky
Survey (SDSS). DR5 includes all survey quality data taken through June 2005 and
represents the completion of the SDSS-I project (whose successor, SDSS-II will
continue through mid-2008). It includes five-band photometric data for 217
million objects selected over 8000 square degrees, and 1,048,960 spectra of
galaxies, quasars, and stars selected from 5713 square degrees of that imaging
data. These numbers represent a roughly 20% increment over those of the Fourth
Data Release; all the data from previous data releases are included in the
present release. In addition to "standard" SDSS observations, DR5 includes
repeat scans of the southern equatorial stripe, imaging scans across M31 and
the core of the Perseus cluster of galaxies, and the first spectroscopic data
from SEGUE, a survey to explore the kinematics and chemical evolution of the
Galaxy. The catalog database incorporates several new features, including
photometric redshifts of galaxies, tables of matched objects in overlap regions
of the imaging survey, and tools that allow precise computations of survey
geometry for statistical investigations.Comment: ApJ Supp, in press, October 2007. This paper describes DR5. The SDSS
Sixth Data Release (DR6) is now public, available from http://www.sdss.or
The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey
The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic
data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data
release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median
z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar
spectra, along with the data presented in previous data releases. These spectra
were obtained with the new BOSS spectrograph and were taken between 2009
December and 2011 July. In addition, the stellar parameters pipeline, which
determines radial velocities, surface temperatures, surface gravities, and
metallicities of stars, has been updated and refined with improvements in
temperature estimates for stars with T_eff<5000 K and in metallicity estimates
for stars with [Fe/H]>-0.5. DR9 includes new stellar parameters for all stars
presented in DR8, including stars from SDSS-I and II, as well as those observed
as part of the SDSS-III Sloan Extension for Galactic Understanding and
Exploration-2 (SEGUE-2).
The astrometry error introduced in the DR8 imaging catalogs has been
corrected in the DR9 data products. The next data release for SDSS-III will be
in Summer 2013, which will present the first data from the Apache Point
Observatory Galactic Evolution Experiment (APOGEE) along with another year of
data from BOSS, followed by the final SDSS-III data release in December 2014.Comment: 9 figures; 2 tables. Submitted to ApJS. DR9 is available at
http://www.sdss3.org/dr
X-Ray-Emitting Stars Identified from the ROSAT All-Sky Survey and the Sloan Digital Sky Survey
The ROSAT All-Sky Survey (RASS) was the first imaging X-ray survey of the
entire sky. While X-ray source counterparts are known to range from distant
quasars to nearby M dwarfs, the RASS data alone are often insufficient to
determine the nature of an X-ray source. As a result, large-scale follow-up
programs are required to construct samples of known X-ray emitters. We use
optical data produced by the Sloan Digital Sky Survey (SDSS) to identify 709
stellar X-ray emitters cataloged in the RASS and falling within the SDSS Data
Release 1 footprint. Most of these are bright stars with coronal X-ray emission
unsuitable for SDSS spectroscopy, which is designed for fainter objects (g > 15
mag). Instead, we use SDSS photometry, correlations with the Two Micron All Sky
Survey and other catalogs, and spectroscopy from the Apache Point Observatory
3.5 m telescope to identify these stellar X-ray counterparts. Our sample of 707
X-ray-emitting F, G, K, and M stars is one of the largest X-ray-selected
samples of such stars. We derive distances to these stars using photometric
parallax relations appropriate for dwarfs on the main sequence, and use these
distances to calculate LX. We also identify a previously unknown cataclysmic
variable (CV) as a RASS counterpart. Separately, we use correlations of the
RASS and the SDSS spectroscopic catalogs of CVs and white dwarfs (WDs) to study
the properties of these rarer X-ray-emitting stars. We examine the relationship
between (fX/fg) and the equivalent width of the Hbeta emission line for 46
X-ray-emitting CVs and discuss tentative classifications for a subset based on
these quantities. We identify 17 new X-ray-emitting DA (hydrogen) WDs, of which
three are newly identified WDs. (abridged)Comment: 23 pages, 15 figures, 8 tables; full catalog available online onl
CD44 Upregulation in E-Cadherin-Negative Esophageal Cancers Results in Cell Invasion
E-cadherin is frequently lost during epithelial-mesenchymal transition and the progression of epithelial tumorigenesis. We found a marker of epithelial-mesenchymal transition, CD44, upregulated in response to functional loss of E-cadherin in esophageal cell lines and cancer. Loss of E-cadherin expression correlates with increased expression of CD44 standard isoform. Using an organotypic reconstruct model, we show increased CD44 expression in areas of cell invasion is associated with MMP-9 at the leading edge. Moreover, Activin A increases cell invasion through CD44 upregulation after E-cadherin loss. Taken together, our results provide functional evidence of CD44 upregulation in esophageal cancer invasion
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