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A New Green Salamander in the Southern Appalachians: Evolutionary History of Aneides aeneus and Implications for Management and Conservation with the Description of a Cryptic Micro-endemic Species (vol 107, pg 748, 2019)
Integrating physiology into correlative models can alter projections of habitat suitability under climate change for a threatened amphibian
Rapid global change has increased interest in developing ways to identify suitable refu-gia for species of conservation concern. Correlative and mechanistic species distribu-tion models (SDMs) represent two approaches to generate spatially-explicit estimates of climate vulnerability. Correlative SDMs generate distributions using statistical associations between environmental variables and species presence data. In contrast, mechanistic SDMs use physiological traits and tolerances to identify areas that meet the conditions required for growth, survival and reproduction. Correlative approaches assume modeled environmental variables influence species distributions directly or indirectly; however, the mechanisms underlying these associations are rarely verified empirically. We compared habitat suitability predictions between a correlative-only SDM, a mechanistic SDM and a correlative framework that incorporated mechanis-tic layers (âhybrid modelsâ). Our comparison focused on green salamanders Aneides aeneus, a priority amphibian threatened by climate change throughout their disjunct range. We developed mechanistic SDMs using experiments to measure the thermal sensitivity of resistance to water loss (ri) and metabolism. Under current climate con-ditions, correlative-only, hybrid and mechanistic SDMs predicted similar overlap in habitat suitability; however, mechanistic SDMs predicted habitat suitability to extend into regions without green salamanders but known to harbor many lungless salaman-ders. Under future warming scenarios, habitat suitability depended on climate sce-nario and SDM type. Correlative and hybrid models predicted a 42% reduction or 260% increase in area considered to be suitable depending on the climate scenario. In mechanistic SDMs, energetically suitable habitat declined with both climate scenarios and was driven by the thermal sensitivity of ri. Our study indicates that correlative-only and hybrid approaches produce similar predictions of habitat suitability; however, discrepancies can arise for species that do not occupy their entire fundamental niche, which may hold consequences of conservation planning of threatened species
Cytosolic Phospholipase A2α and Eicosanoids Regulate Expression of Genes in Macrophages Involved in Host Defense and Inflammation
Acknowledgments: We thank Dr. Robert Barkley and Charis Uhlson for mass spectrometry analysis. Funding: This work was supported by grants from the National Institutes of Health HL34303 (to C.C.L., R.C.M. and D.L.B), DK54741 (to J.V.B.), GM5322 (to D.L.W.) and the Wellcome Trust (to N.A.R.G. and G.D.B.). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD
The Panchromatic Hubble Andromeda Treasury. Progression of Large-Scale Star Formation across Space and Time in M31
We investigate the clustering of early-type stars younger than 300 Myr on
galactic scales in M31. Based on the stellar photometric catalogs of the
Panchromatic Hubble Andromeda Treasury program that also provides stellar
parameters derived from the individual energy distributions, our analysis is
focused on the young stars in three star-forming regions, located at
galactocentric distances of about 5, 10, and 15 kpc, corresponding to the inner
spiral arms, the ring structure, and the outer arm, respectively. We apply the
two-point correlation function to our selected sample to investigate the
clustering behavior of these stars across different time- and length-scales. We
find that young stellar structure survives across the whole extent of M31
longer than 300 Myr. Stellar distribution in all regions appears to be
self-similar, with younger stars being systematically more strongly clustered
than the older, which are more dispersed. The observed clustering is
interpreted as being induced by turbulence, the driving source for which is
probably gravitational instabilities driven by the spiral arms, which are
stronger closer to the galactic centre.Comment: 10 pages, 5 figures. To appear in "LESSONS FROM THE LOCAL GROUP - A
Conference in Honour of David Block and Bruce Elmegreen" eds. Freeman, K.C.,
Elmegreen, B.G., Block, D.L. & Woolway, M. (Springer: New York
Spitzer, Near-Infrared, and Submillimeter Imaging of the Relatively Sparse Young Cluster, Lynds 988e
We present {\it Spitzer} images of the relatively sparse, low luminosity
young cluster L988e, as well as complementary near-infrared (NIR) and
submillimeter images of the region. The cluster is asymmetric, with the western
region of the cluster embedded within the molecular cloud, and the slightly
less dense eastern region to the east of, and on the edge of, the molecular
cloud. With these data, as well as with extant H data of stars
primarily found in the eastern region of the cluster, and a molecular CO
gas emission map of the entire region, we investigate the distribution of
forming young stars with respect to the cloud material, concentrating
particularly on the differences and similarities between the exposed and
embedded regions of the cluster. We also compare star formation in this region
to that in denser, more luminous and more massive clusters already investigated
in our comprehensive multi-wavelength study of young clusters within 1 kpc of
the Sun.Comment: 21 pages, 6 tables, 13 figures. Full resolution figures at:
http://astro.pas.rochester.edu/~tom/Preprints/L988e.pd
The Initial Configuration of Young Stellar Clusters: A K-band Number Counts Analysis of the Surface Density of Stars
We present an analysis of K-band stellar distributions for the young stellar
clusters GGD 12-15, IRAS 20050+2720, and NGC 7129. We find that the two deeply
embedded clusters, GGD 12-15 and IRAS 20050+2720, are not azimuthally symmetric
and show a high degree of structure which traces filamentary structure observed
in 850 micron emission maps. In contrast, the NGC 7129 cluster is circularly
symmetric, less dense, and anti-correlated to 850 micron emission, suggesting
recent gas expulsion and dynamical expansion have occured. We estimate stellar
volume densities from nearest neighbor distances, and discuss the impact of
these densities on the evolution of circumstellar disks and protostellar
envelopes in these regions.Comment: 44 pages, 26 figures, Accepted to ApJ. Changes include extinction
mapping, Monte Carlo field star modeling, and Nyquist sampled azimuthal
stellar distributions. A version with full resolution figures is available at
http://astro.pas.rochester.edu/~rguter/preprints/gutermuth_sd.tar.g
PHAT Stellar Cluster Survey I. Year 1 Catalog and Integrated Photometry
The Panchromatic Hubble Andromeda Treasury (PHAT) survey is an on-going
Hubble Space Telescope (HST) multi-cycle program to obtain high spatial
resolution imaging of one-third of the M31 disk at ultraviolet through
near-infrared wavelengths. In this paper, we present the first installment of
the PHAT stellar cluster catalog. When completed, the PHAT cluster catalog will
be among the largest and most comprehensive surveys of resolved star clusters
in any galaxy. The exquisite spatial resolution achieved with HST has allowed
us to identify hundreds of new clusters that were previously inaccessible with
existing ground-based surveys. We identify 601 clusters in the Year 1 sample,
representing more than a factor of four increase over previous catalogs within
the current survey area (390 arcmin^2). This work presents results derived from
the first \sim25% of the survey data; we estimate that the final sample will
include \sim2500 clusters. For the Year 1 objects, we present a catalog with
positions, radii, and six-band integrated photometry. Along with a general
characterization of the cluster luminosities and colors, we discuss the cluster
luminosity function, the cluster size distributions, and highlight a number of
individually interesting clusters found in the Year 1 search.Comment: 26 pages, 22 figures, Accepted by Ap
A case series study on the effect of Ebola on facility-based deliveries in rural Liberia
Abstract
Background
As communitiesâ fears of Ebola virus disease (EVD) in West Africa exacerbate and their trust in healthcare providers diminishes, EVD has the potential to reverse the recent progress made in promoting facility-based delivery. Using retrospective data from a study focused on maternal and newborn health, this analysis examined the influence of EVD on the use of facility-based maternity care in Bong Country, Liberia, which shares a boarder with Sierra Leone - near the epicenter of the outbreak.
Methods
Using a case series design, retrospective data from logbooks were collected at 12 study sites in one county. These data were then analyzed to determine womenâs use of facility-based maternity care between January 2012 and October 2014. The primary outcome was the number of facility-based deliveries over time. The first suspected case of EVD in Bong County was reported on June 30, 2014. Heat maps were generated and the number of deliveries was normalized to the average number of deliveries during the full 12 months before the EVD outbreak (March 2013 â February 2014).
Results
Prior to the EVD outbreak, facility-based deliveries steadily increased in Bong County reaching an all-time high of over 500 per month at study sites in the first half of 2014 â indicating Liberia was making inroads in normalizing institutional maternal healthcare. However, as reports of EVD escalated, facility-based deliveries decreased to a low of 113 in August 2014.
Conclusion
Ebola virus disease has negatively impacted the use of facility-based maternity services, placing childbearing women at increased risk for morbidity and death.http://deepblue.lib.umich.edu/bitstream/2027.42/114384/1/12884_2015_Article_694.pd
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