1,462 research outputs found
Athletics\u27 Place In Education
The question asked by college students, college athletes, college faculty members, and the world at large is, What is the place athletics should hold in our present (lay educational system, or do athletics belong at all in the college program? The question is a natural one because there exist arguments pro and con. I believe the arguments for athletics far outweigh those listed against them
Nuclear gas dynamics in Arp 220 - sub-kiloparsec scale atomic hydrogen disks
We present new, high angular resolution (~0.22") MERLIN observations of
neutral hydrogen (HI) absorption and 21-cm radio continuum emission across the
central ~900 parsecs of the ultraluminous infrared galaxy, Arp220. Spatially
resolved HI absorption is detected against the morphologically complex and
extended 21-cm radio continuum emission, consistent with two counterrotating
disks of neutral hydrogen, with a small bridge of gas connecting the two.
We propose a merger model in which the two nuclei represent the galaxy cores
which have survived the initial encounter and are now in the final stages of
merging, similar to conclusions drawn from previous CO studies (Sakamoto,
Scoville & Yun 1999). However, we suggest that instead of being coplanar with
the main CO disk (in which the eastern nucleus is embedded), the western
nucleus lies above it and, as suggested by bridge of HI connecting the two
nuclei, will soon complete its final merger with the main disk. We suggest that
the collection of radio supernovae (RSN) detected in VLBA studies in the more
compact western nucleus represent the second burst of star formation associated
with this final merger stage and that free-free absorption due to ionised gas
in the bulge-like component can account for the observed RSN distribution.
(Abridged)Comment: 26 pages including 8 figures and 1 table; accepted for publication in
Ap
Protein expression and genetic variability of canine Can f 1 in golden and Labrador retriever service dogs.
BackgroundValued for trainability in diverse tasks, dogs are the primary service animal used to assist individuals with disabilities. Despite their utility, many people in need of service dogs are sensitive to the primary dog allergen, Can f 1, encoded by the Lipocalin 1 gene (LCN1). Several organizations specifically breed service dogs to meet special needs and would like to reduce allergenic potential if possible. In this study, we evaluated the expression of Can f 1 protein and the inherent variability of LCN1 in two breeds used extensively as service dogs. Saliva samples from equal numbers of male and female Labrador retrievers (n = 12), golden retrievers (n = 12), and Labrador-golden crosses (n = 12) were collected 1 h after the morning meal. Can f 1 protein concentrations in the saliva were measured by ELISA, and the LCN1 5' and 3' UTRs and exons sequenced.ResultsThere was no sex effect (p > 0.2) nor time-of-day effect; however, Can f 1 protein levels varied by breed with Labrador retrievers being lower than golden retrievers (3.18 ± 0.51 and 5.35 ± 0.52 μg/ml, respectively, p < 0.0075), and the Labrador-golden crosses having intermediate levels (3.77 ± 0.48 μg/ml). Although several novel SNPs were identified in LCN1, there were no significant breed-specific sequence differences in the gene and no association of LCN1 genotypes with Can f 1 expression.ConclusionsAs service dogs, Labrador retrievers likely have lower allergenic potential and, though there were no DNA sequence differences identified, classical genetic selection on the estimated breeding values associated with salivary Can f 1 expression may further reduce that potential
Early GRB Optical and Infrared Afterglow Observations with the 2-m Robotic Liverpool Telescope
We present the first optical observations of a Gamma Ray Burst (GRB)
afterglow using the 2-m robotic Liverpool Telescope (LT), which is owned and
operated by Liverpool John Moores University and situated on La Palma. We
briefly discuss the capabilities of LT and its suitability for rapid follow-up
observations of early optical and infrared GRB light curves. In particular, the
combination of aperture, site, instrumentation and rapid response (robotic
over-ride mode aided by telescope's rapid slew and fully-opening enclosure)
makes the LT ideal for investigating the nature of short bursts, optically-dark
bursts, and GRB blast-wave physics in general. We briefly describe the LT's key
position in the RoboNet-1.0 network of robotic telescopes. We present the LT
observations of GRB041006 and use its gamma-ray properties to predict the time
of the break in optical light curve, a prediction consistent with the
observations.Comment: 4 pages, 1 figure, accepted for publication in Il nuovo cimento (4th
Workshop Gamma-Ray Bursts in the Afterglow Era, Rome, 18-22 October 2004
The Cold and Hot Gas Content of Fine-Structure E and S0 Galaxies
We investigate trends of the cold and hot gas content of early-type galaxies
with the presence of optical morphological peculiarities, as measured by the
fine-structure index (Sigma). HI mapping observations from the literature are
used to track the cold-gas content, and archival ROSAT PSPC data are used to
quantify the hot-gas content. We find that E and S0 galaxies with a high
incidence of optical peculiarities are exclusively X-ray underluminous and,
therefore, deficient in hot gas. In contrast, more relaxed galaxies with little
or no signs of optical peculiarities span a wide range of X-ray luminosities.
That is, the X-ray excess anticorrelates with Sigma. There appears to be no
similar trend of cold-gas content with either fine-structure index or X-ray
content. The fact that only apparently relaxed E and S0 galaxies are strong
X-ray emitters is consistent with the hypothesis that after strong disturbances
such as a merger hot-gas halos build up over a time scale of several gigayears.
This is consistent with the expected mass loss from stars.Comment: 12 pages, latex, 5 figures. Accepted for publication in A
Excessive Seepage Losses at Westwood Lake Dam
Excessive seepage losses at Westwood Lake Darn in east-central Indiana were apparent in 1974 during first filling of the lake when seepage areas developed downstream of the dam and abutments. Several remedial studies were performed which included additional test borings, field and laboratory tests, installation of observation wells, and a review of the site geology and hydrology. Data and observations from these studies were used to develop semi-quantitative assessments of seepage loss rates as related to lake levels. These analyses served as a basis for design of a major repair which consisted of blanketing a significant portion of the lake bottom with on-site, low-plasticity clays and clayey silts. The blanketing was completed in 1984 and postrepair filling required about two years. Subsequent monitoring and observations indicate that the lake level is holding at or within 1.5 ft of the original design normal pool
Explaining two circumnuclear star forming rings in NGC5248
The distribution of gas in the central kiloparsec of a galaxy has a
dynamically rapid evolution. Nonaxisymmetries in the gravitational potential of
the galactic disk, such as a large scale stellar bar or spiral, can lead to
significant radial motion of gaseous material from larger radii to the central
region. The large influx of gas and the subsequent star formation keep the
central region constantly changing. However, the ability of gas to reach the
nucleus proper to fuel an AGN phase is not guaranteed. Gas inflow can be halted
at a circumnuclear star forming ring several hundred parsec away. The nearby
galaxy NGC5248 is especially interesting in this sense since it is said to host
2 circumnuclear star forming rings at 100pc and 370pc from its quiescent
nucleus. Here we present new subarcsecond PdBI+30m CO(2-1) emission line
observations of the central region. For the first time the molecular gas
distribution at the smallest stellar ring is resolved into a gas ring,
consistent with the presence of a quiescent nucleus. However, the molecular gas
shows no ring structure at the larger ring. We combine analyses of the gaseous
and stellar content in the central kiloparsec of this galaxy to understand the
gas distribution and dynamics of this star forming central region. We discuss
the probability of two scenarios leading to the current observations, given our
full understanding of this system, and discuss whether there are really two
circumnuclear star forming rings in this galaxy.Comment: Accepted for publication in A&A, 14pages + long tabl
Feeding versus Feedback in NGC 4151 probed with Gemini NIFS. I. Excitation
We have used the Gemini Near-infrared Integral Field Spectrograph (NIFS) to
map the emission-line intensity distributions and ratios in the Narrow-Line
Region (NLR) of the Seyfert galaxy NGC 4151 in the Z, J, H and K bands at a
resolving power ~ 5000, covering the inner 200 pc x 300 pc of the galaxy at a
spatial resolution of 8 pc. We present intensity distributions I(r) in 14
emission lines. (1) For the ionized gas, I(r) is extended to ~ 100 pc from the
nucleus along pos. angle PA=60/240 deg-- NE--SW), consistent with an origin in
the known biconical outflow; while for the recombination lines I(r) ~ r^-1, for
the forbidden lines I(r) is flat (r^0). (2) The H_2 emission lines intensity
distributions avoid the region of the bicone, extending to r ~ 60 pc,
perpendicular to the bicone axis, supporting an origin for the H_2-emitting gas
in the galaxy plane. (3) The coronal lines show a steep intensity profile,
described by r^-2. Using the line-ratio maps [Fe II]1.644/1.257 and Pa_b/Br_g
we obtain a reddening of E(B-V)~0.5 along the NLR and E(B-V)>1 at the nucleus.
Our line-ratio map [Fe II] 1.257/[P II] 1.189 is the first such map of an
extragalactic source. Together with the [Fe II]/Pa_b map, these line ratios
correlate with the radio intensity distribution, mapping the effects of shocks
produced by the radio jet, which probably release the Fe locked in grains and
produce the enhancement of the [Fe II] emission observed at ~ 1 arcsec from the
nucleus. At these regions, we obtain densities N_e ~4000 cm^-3 and temperatures
T_e ~ 15000K for the [Fe II]-emitting gas. For the H_2-emitting gas we obtain T
~ 2100K. The distinct intensity distributions, physical properties and
locations of the ionized and molecular gas suggest that the H_2-emitting gas
traces the AGN feeding, while the ionized gas traces its feedback.Comment: 22 pages. 14 figures, accepted for publication in MNRA
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