1,729 research outputs found
Winter feeding dairy cows
1 online resource (PDF, 2 pages)This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu
Ultraviolet Imaging of the Globular Cluster 47 Tucanae
We have used the Ultraviolet Imaging Telescope to obtain deep far-UV (1620
Angstrom), 40' diameter images of the prototypical metal-rich globular cluster
47 Tucanae. We find a population of about 20 hot (Teff > 9000 K) objects near
or above the predicted UV luminosity of the hot horizontal branch (HB) and
lying within two half-light radii of the cluster center. We believe these are
normal hot HB or post-HB objects rather than interacting binaries or blue
stragglers. IUE spectra of two are consistent with post-HB phases. These
observations, and recent HST photometry of two other metal-rich clusters,
demonstrate that populations with rich, cool HB's can nonetheless produce hot
HB and post-HB stars. The cluster center also contains an unusual diffuse
far-UV source which is more extended than its V-band light. It is possible that
this is associated with an intracluster medium, for which there was earlier
infrared and X-ray evidence, and is produced by C IV emission or scattered
light from grains.Comment: 13 pages AASLaTeX including one postscript figure and one bitmapped
image, JPEG format. Submitted to the Astronomical Jorunal. Full Postscript
version available at http://www.astro.virginia.edu/~bd4r
DHIA Records
This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu
Ultraviolet Imagery of NGC 6752: A Test of Extreme Horizontal Branch Models
We present a 1620 A image of the nearby globular cluster NGC 6752 obtained
with the Ultraviolet Imaging Telescope (UIT) during the Astro-2 mission of the
Space Shuttle Endeavour in 1995 March. An ultraviolet-visible color-magnitude
diagram (CMD) is derived for 216 stars matched with the visible photometry of
Buonanno et al. (1986). This CMD provides a nearly complete census of the hot
horizontal branch (HB) population with good temperature and luminosity
discrimination for comparison with theoretical tracks. The observed data show
good agreement with the theoretical zero-age horizontal branch (ZAHB) of
Sweigart (1996) for an assumed reddening of E(B-V) = 0.05 and a distance
modulus of 13.05. The observed HB luminosity width is in excellent agreement
with the theoretical models and supports the single star scenario for the
origin of extreme horizontal branch (EHB) stars. However, only four stars can
be identified as post-EHB stars, whereas almost three times this many are
expected from the HB number counts. If this effect is not a statistical
anomaly, then some non-canonical effect may be decreasing the post-EHB
lifetime. The recent non-canonical models of Sweigart (1996), which have
helium-enriched envelopes due to mixing along the red giant branch, cannot
explain the deficit of post-EHB stars, but might be better able to explain
their luminosity distribution.Comment: 14 pages, AASTeX, includes 4 EPS figures ApJ Letters accepte
Combinations of idelalisib with rituximab and/or bendamustine in patients with recurrent indolent non-Hodgkin lymphoma
Key Points
Combining phosphatidylinositol-3-kinase Ī“ inhibition with rituximab, bendamustine, or both is feasible and active in relapsed iNHL. The safety of novel combinations should be proven in phase 3 trials before adoption in clinical practice.</jats:p
UIT Detection of Hot Stars in the Globular Cluster NGC362
We used the Ultraviolet Imaging Telescope during the March 1995 Astro-2
mission to obtain a deep far-UV image of the globular cluster NGC 362, which
was formerly thought to have an almost entirely red horizontal branch (HB). 84
hot (T_eff > 8500 K) stars were detected within a radius of 8'.25 of the
cluster center. Of these, 43 have FUV magnitudes consistent with HB stars in
NGC 362, and at least 34 are cluster members. The number of cluster members is
made uncertain by background contamination from blue stars in the Small
Magellanic Cloud (SMC). There are six candidate supra-HB stars which have
probably evolved from the HB. We discuss the implications of these results for
the production of hot blue stars in stellar populations.Comment: 10 pages AASLaTeX including one postscript figure and one compressed
bitmap, .jpg format. To appear in Ap. J. Letters. Postscript version also
available at http://www.astro.virginia.edu/~bd4r
Transcriptional Profiling of Aging in Human Muscle Reveals a Common Aging Signature
We analyzed expression of 81 normal muscle samples from humans of varying ages, and have identified a molecular profile for aging consisting of 250 age-regulated genes. This molecular profile correlates not only with chronological age but also with a measure of physiological age. We compared the transcriptional profile of muscle aging to previous transcriptional profiles of aging in the kidney and the brain, and found a common signature for aging in these diverse human tissues. The common aging signature consists of six genetic pathways; four pathways increase expression with age (genes in the extracellular matrix, genes involved in cell growth, genes encoding factors involved in complement activation, and genes encoding components of the cytosolic ribosome), while two pathways decrease expression with age (genes involved in chloride transport and genes encoding subunits of the mitochondrial electron transport chain). We also compared transcriptional profiles of aging in humans to those of the mouse and fly, and found that the electron transport chain pathway decreases expression with age in all three organisms, suggesting that this may be a public marker for aging across species
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