3,291 research outputs found
A Bait Attractant Study of the Nitidulidae (Coleoptera) at Shawnee State Forest in Southern Ohio
Four baits were tested for efficacy in attracting sap beetles (Nitidulidae) at two sites in the Shawnee State Forest over two collection periods in 1992. Species taken were categorized into three groups: abundant, moderate, and uncommon. At Site 1, nitidulids displayed a strong preference for whole wheat bread dough, followed by fermenting brown sugar, and fermenting malt/molasses solution, and vinegar, respectively. Site 2 collections showed a similar trend to Site 1, but the order of preference was switched for brown sugar and malt/molasses solution. Of the 20 species collected, six species were abundant, seven species were moderate, and seven species were locally uncommon
The Leopold Center for Sustainable Agriculture: An Overview
The Leopold Center for Sustainable Agriculture was established in the 1987 Groundwater Protection Act. CH. 225, Sec. 230. The legislation defines sustainable agriculture as the appropriate use of crop and livestock systems and agricultural inputs supporting those activities which maintain economic and social viability while preserving the high productivity and quality of Iowa\u27s land
Optical and X-ray Properties of the Swift BAT-detected AGN
The Swift Gamma-Ray Burst satellite has detected a largely unbiased towards
absorption sample of local () AGN, based solely on their
14--195 keV flux. In the first 9 months of the survey, 153 AGN sources were
detected. The X-ray properties in the 0.3--10 keV band have been compiled and
presented based on analyses with XMM-Newton, Chandra, Suzaku, and the Swift XRT
(Winter et al. 2009). Additionally, we have compiled a sub-sample of sources
with medium resolution optical ground-based spectra from the SDSS or our own
observations at KPNO. In this sample of 60 sources, we have classified the
sources using standard emission line diagnostic plots, obtained masses for the
broad line sources through measurement of the broad H emission line, and
measured the [OIII] 5007\AA luminosity of this sample. Based on continuum fits
to the intrinsic absorption features, we have obtained clues about the stellar
populations of the host galaxies. We now present the highlights of our X-ray
and optical studies of this unique sample of local AGNs, including a comparison
of the 2--10 keV and 14--195 keV X-ray luminosities with the [OIII] 5007\AA
luminosity and the implications of our results towards measurements of
bolometric luminosities.Comment: 4 pages, 2 figures, to appear in proceedings for 'X-ray Astronomy
2009', Bologna 09/2009, AIP Conference Series, Eds. A. Comastri, M. Cappi, L.
Angelin
A Detection of Gas Associated with the M 31 Stellar Stream
Detailed studies of stellar populations in the halos of the Milky Way and the
Andromeda (M 31) galaxies have shown increasing numbers of tidal streams and
dwarf galaxies, attesting to a complicated and on-going process of hierarchical
structure formation. The most prominent feature in the halo of M 31 is the
Giant Stellar Stream, a structure ~4.5 degrees in extent along the sky, which
is close to, but not coincident with the galaxy's minor axis. The stars that
make up this stream are kinematically and chemically distinct from the other
stars in the halo. Here, we present HST/COS high-resolution ultraviolet
absorption spectra of three Active Galactic Nuclei sight lines which probe the
M 31 halo, including one that samples gas in the main southwestern portion of
the Giant Stream. We see two clear absorption components in many metal species
at velocities typical of the M 31 halo and a third, blue-shifted component
which arises in the stream. Photoionization modeling of the column density
ratios in the different components shows gas in an ionization state typical of
that seen in other galaxy halo environments and suggests solar to slightly
super-solar metallicity, consistent with previous findings from stellar
spectroscopy.Comment: 10 pages, 5 figures, accepted for publication in the Astrophysical
Journa
Chapter 1. The Nitrogen Cycle, Historical Perspective, and Current and Potential Future Concerns
Nitrogen (N) along with carbon and oxygen is the most complex and crucial of the elements essential for life. Supplementing grain and grass forage crops with organic and inorganic N fertilizers has long been recognized as a key to improving crop yields and economic returns. Globally. N fertilizer is largely used for cereal grain production and accounts for an estimated 40(1r of the increase in per capita food production in the past 50 years (Mosier et al.. 200 I). Smil (200 I) estimates that N fertilizer supplies up to 40% of the world\u27s dietary protein and dependence on N from the Haber-Bosch process will increase in the future. Nitrogen compounds also have been recognized for their many potential adverse impacts on the environment and health (Keeney. 2002)
Agricultural Contribution of Nitrate-N to the Des Moines River: 1945 vs. 1980
Recently, intensive water quality monitoring has demonstrated the presence of nitrate (N03-N) in surface and groundwater throughout the Midwestern U.S. (Hallberg, 1989)
Discovery of a Dwarf Post-Starburst Galaxy Near a High Column Density Ly-alpha Absorber
We report the discovery of a dwarf (M_B = -13.9) post-starburst galaxy
coincident in recession velocity (within uncertainties) with the highest column
density absorber (N_HI = 10^15.85 cm^{-2} at cz = 1586 km/s) in the 3C~273
sightline. This galaxy is by far the closest galaxy to this absorber, projected
just 71 kpc on the sky from the sightline. The mean properties of the stellar
populations in this galaxy are consistent with a massive starburst ~3.5 Gyrs
ago, whose attendant supernovae, we argue, could have driven sufficient gas
from this galaxy to explain the nearby absorber. Beyond the proximity on the
sky and in recession velocity, the further evidence in favor of this conclusion
includes both a match in the metallicities of absorber and galaxy, and the fact
that the absorber has an overabundance of Si/C, suggesting recent type II
supernova enrichment. Thus, this galaxy and its ejecta are the expected
intermediate stage in the fading dwarf evolutionary sequence envisioned by
Babul & Rees to explain the abundance of faint blue galaxies at intermediate
redshifts.Comment: 33 pages, 4 figures, ApJ in pres
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