115 research outputs found
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Stratigraphy and structure of the Snowflake Ridge area, Gallatin County, Montana
Engaging community planners and local elected officials with local food systems producers to integrate local food systems into community plans and policies
Researchers examined three key obstacles to making progress in local food systems from a planning and land use perspective that could be handled by applying community planning tactics
Modulation of proinflammatory activity by the engineered cationic antimicrobial peptide WLBU-2
Sarcoidosis of the Mandibular Condyle: A Rare Disease That Can Mimic Malignancy
Sarcoidosis can involve any of the organs, however intraosseous involvement is rare and ranges from 5 to 15%, with lesions of the mandible being even rarer – currently with few known cases reported. Intraosseous lesions involving the mandible have been noted to be asymptomatic or associated with chronic jaw pain. Additionally, mandibular involvement can present as a lytic bone lesion mimicking osseous malignancy. Chronic polyarthritis is commonly associated with the progression of sarcoidosis and intraosseous involvement has been considered a late-stage sequelae. We report a case of biopsy-proven sarcoidosis within the mandibular condyle in an asymptomatic 56-year-old Caucasian female who had no preceding polyarthritis or symptomatic progression of disease, discuss the imaging features, and report management
Understanding cross-cultural sales manager-salesperson relationships in the Asia-Pacific rim region : a grounded theory approach
As more organizations implement multinational strategies, sales managers leading sales forces encounter complex cultural challenges that affect relationships, processes, and outcomes. We undertake a qualitative study with the objective of understanding the sales manager–salesperson relationship when the sales manager is leading sales representatives located in other cultures. Because of the significant size and growth of Asian countries, we focus our study on the Asia-Pacific Rim region. In-depth interviews conducted with 21 sales managers working for a large multinational technology firm in our focal region provide the data for our analysis. Using a grounded theory approach, we identify five key themes: building and sustaining cross-cultural relationships, cross-cultural communication effectiveness, acquisition and maintenance of trust across cultures, language, and decision-making. From our findings, research propositions are offered and implications for researchers and practitioners are discussed
Alignment of Brightest Cluster Galaxies with their Host Clusters
We examine the alignment between Brightest Cluster Galaxies (BCGs) and their
host clusters in a sample of 7031 clusters with 0.08<z<0.44 found using a
matched-filter algorithm and an independent sample of 5744 clusters with
0.1<z<0.3 selected with the maxBCG algorithm, both extracted from the Sloan
Digital Sky Survey Data Release 6 imaging data. We confirm that BCGs are
preferentially aligned with the cluster's major axis; clusters with dominant
BCGs (>0.65 mag brighter than the mean of the second and third ranked galaxies)
show stronger alignment than do clusters with less dominant BCGs at the 4.4
sigma level. Rich clusters show a stronger alignment than do poor clusters at
the 2.3 sigma level. Low redshift clusters (z<0.26) show more alignment than do
high redshift (z>0.26) clusters, with a difference significant at the 3.0 sigma
level. Our results do not depend on the algorithm used to select the cluster
sample, suggesting that they are not biased by systematics of either algorithm.
The correlation between BCG dominance and cluster alignment may be a
consequence of the hierarchical merging process which forms the cluster. The
observed redshift evolution may follow from secondary infall at late redshifts.Comment: 15 pages, 12 Figures, 10 Tables, Accepted for publication in MNRA
Host Galaxies of Luminous Type 2 Quasars at z ~ 0.5
We present deep Gemini GMOS optical spectroscopy of nine luminous quasars at
redshifts z ~ 0.5, drawn from the SDSS type 2 quasar sample. Our targets were
selected to have high intrinsic luminosities (M_V < -26 mag) as indicated by
the [O III] 5007 A emission-line luminosity (L_[O III]). Our sample has a
median black hole mass of ~ 10^8.8 M_sun inferred assuming the local
M_BH-sigma_* relation and a median Eddington ratio of ~ 0.7, using stellar
velocity dispersions sigma_* measured from the G band. We estimate the
contamination of the stellar continuum from scattered quasar light based on the
strength of broad H-beta, and provide an empirical calibration of the
contamination as a function of L_[O III]; the scattered light fraction is ~ 30%
of L_5100 for objects with L_[O III] = 10^9.5 L_sun. Population synthesis
indicates that young post-starburst populations (< 0.1 Gyr) are prevalent in
luminous type 2 quasars, in addition to a relatively old population (> 1 Gyr)
which dominates the stellar mass. Broad emission complexes around He II 4686 A
with luminosities up to 10^8.3 L_sun are unambiguously detected in three out of
the nine targets, indicative of Wolf-Rayet populations. Population synthesis
shows that ~ 5-Myr post-starburst populations contribute substantially to the
luminosities (> 50% of L_5100) of all three objects with Wolf-Rayet detections.
We find two objects with double cores and four with close companions. Our
results may suggest that luminous type 2 quasars trace an early stage of galaxy
interaction, perhaps responsible for both the quasar and the starburst
activity.Comment: 20 pages, 13 figures, 7 tables; accepted to Ap
Local Lyman Break Galaxy Analogs: The Impact of Massive Star-forming Clumps on the Interstellar Medium and the Global Structure of Young, Forming Galaxies
We present HST UV/optical imaging, Spitzer mid-IR photometry, and optical
spectroscopy of a sample of 30 low-redshift (z=0.1-0.3) galaxies chosen from
SDSS/GALEX to be accurate local analogs of the high-z Lyman Break Galaxies. The
Lyman Break Analogs (LBAs) are similar in mass, metallicity, dust, SFR, size
and gas velocity dispersion, thus enabling a detailed investigation of
processes that are important at high-z. The optical emission line properties of
LBAs are also similar to those of LBGs, indicating comparable conditions in
their ISM. In the UV, LBAs are characterized by complexes of massive
star-forming "clumps", while in the optical they most often show evidence for
(post-)mergers/interactions. In 6 cases, we find an extremely massive (>10^9
Msun) compact (R~100 pc) dominant central object (DCO). The DCOs are
preferentially found in LBAs with the highest mid-IR luminosities and
correspondingly high SFRs (15-100 Msun/yr). We show that the massive SF clumps
(including the DCOs) have masses much larger than the nuclear super star
clusters seen in normal late type galaxies. However, the DCOs have masses,
sizes, and densities similar to the excess-light/central-cusps seen in typical
elliptical galaxies with masses similar to the LBA galaxies. We suggest that
the DCOs form in present-day examples of the dissipative mergers at high
redshift that are believed to have produced the central-cusps in local
ellipticals. More generally, the properties of the LBAs are consistent with the
idea that instabilities in a gas-rich disk lead to very massive star-forming
clumps that eventually coalesce to form a spheroid. We speculate that the DCOs
are too young at present to be growing a supermassive black hole because they
are still in a supernova-dominated outflow phase.Comment: The Astrophysical Journal, In Press (22 pages, 16 figures). For the
full version with high-resolution colour figures, see:
http://www.mpa-garching.mpg.de/~overzier/Overzier_LBApaper09.pd
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 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
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