694 research outputs found
Efficient Cosmological Parameter Estimation from Microwave Background Anisotropies
We revisit the issue of cosmological parameter estimation in light of current
and upcoming high-precision measurements of the cosmic microwave background
power spectrum. Physical quantities which determine the power spectrum are
reviewed, and their connection to familiar cosmological parameters is
explicated. We present a set of physical parameters, analytic functions of the
usual cosmological parameters, upon which the microwave background power
spectrum depends linearly (or with some other simple dependence) over a wide
range of parameter values. With such a set of parameters, microwave background
power spectra can be estimated with high accuracy and negligible computational
effort, vastly increasing the efficiency of cosmological parameter error
determination. The techniques presented here allow calculation of microwave
background power spectra times faster than comparably accurate direct
codes (after precomputing a handful of power spectra). We discuss various
issues of parameter estimation, including parameter degeneracies, numerical
precision, mapping between physical and cosmological parameters, and systematic
errors, and illustrate these considerations with an idealized model of the MAP
experiment.Comment: 22 pages, 12 figure
A tandem duplication within the fibrillin 1 gene is associated with the mouse tight skin mutation.
Mice carrying the Tight skin (Tsk) mutation have thickened skin and visceral fibrosis resulting from an accumulation of extracellular matrix molecules. These and other connective tissue abnormalities have made Tskl + mice models for scleroderma, hereditary emphysema, and myocardial hypertrophy. Previously we localized Tsk to mouse chromosome 2 in a region syntenic with human chromosome 15. The microfibrillar glycoprotein gene, fibrillin 1 (FBN1), on human chromosome 15q, provided a candidate for the Tsk mutation. We now demonstrate that the Tsk chromosome harbors a 30- to 40-kb genomic duplication within the Fbn1 gene that results in a larger than normal in-frame Fbn1 transcript. These findings provide hypotheses to explain some of the phenotypic characteristics of Tskl + mice and the lethality of Tsk/Tsk embryos
Insight Timer
Mission Statement: To provide cost-effective avenues for tangible stress reduction and relief for low-income communities such as Wellspring.
Overview: Insight Timer is a mobile application that offers guided meditation to calm the mind, reduce anxiety, manage stress, sleep deeply, and improve happiness. While also offering calm music, courses, live events, and workshops in various languages. (Insight Network, Inc., n.d.)
Problem Statement: Individuals who face poverty experience mental challenges due to stressors caused by poverty due to insecurity and uncertainty about food, housing, and income. Low-income communities tend to have limited resources, poor housing, experience high crime rates, violence rate, and inadequate education. This leads to individuals encountering several barriers to receiving and accessing mental health services. (Low-Income Communities- Anxiety and Depression Association of America, ADAA, n.d.
A Comparison of Wolf Depredation Sites in Areas With Migratory and Resident Elk
As large carnivores recover in many wilderness areas and mixed-use landscapes, wildlife management agencies must seek ways to minimize private property damage while maintaining viable populations. Although much is known about carnivore-livestock conflicts, drivers of these processes in the Northern Rocky Mountains are still emerging amid the dynamic conditions of recovering predator populations (gray wolves [Canis lupus] and grizzly bears [Ursus arctos horribilis]), declining elk productivity, and the re-distribution of migratory and resident elk subpopulations. There has been little research to date that examines the influence of fine-scale elk distribution and movements on patterns of livestock depredation. In this study, we analyze four years of cattle depredation data, two years of summer and fall wolf predation data (n = 4 wolves), and three years of elk movement data (n= 86 elk) to assess the influence of migratory and resident prey on the location and occurrence of wolf depredations on cattle. Wolves living in migratory elk areas face low densities of their preferred prey in summer, when elk depart for higher elevations inside Yellowstone National Park (YNP), while wolves living in the resident elk area have access to abundant elk year round. Wolves living in both areas have the potential to interact with several thousand head of cattle. We used logistic regression to compare the relative influence of landscape features on the risk of livestock depredation in the migratory and resident elk areas. Locations of wolf-killed cattle showed differences between the migratory elk area and the resident elk area. Depredation sites in the resident elk area were associated with habitats closer to roads and with high elk density, while depredation sites in the migratory elk area were associated with dens, streams, and open habitat away from the forest edge. Our findings indicate that knowledge of ungulate distributions and migration patterns can help understand and predict hotspots of wolf conflict with livestock
Southern Cosmology Survey III: QSO's from Combined GALEX and Optical Photometry
We present catalogs of QSO candidates selected using photometry from GALEX
combined with SDSS in the Stripe 82 region and Blanco Cosmology Survey (BCS)
near declination -55 degrees. The SDSS region contains ~700 objects with
magnitude i < 20 and ~3600 objects with i < 21.5 in a ~60 square degree sky
region, while the BCS region contains ~280 objects with magnitude i < 20 and
~2000 objects with i < 21.5 for a 11 square degree sky region that is being
observed by three current microwave Sunyaev-Zeldovich surveys. Our QSO catalog
is the first one in the BCS region. Deep GALEX exposures (~2000 seconds in FUV
and NUV, except in three fields) provide high signal-to-noise photometry in the
GALEX bands (FUV, NUV < 24.5 mag). From this data, we select QSO candidates
using only GALEX and optical r-band photometry, using the method given by Atlee
and Gould (2008). In the Stripe 82 field, 60% (30%) of the GALEX selected QSO's
with optical magnitude i<20 (i<21.5) also appear in the Richards et al. (2008)
QSO catalog constructed using 5-band optical SDSS photometry. Comparison with
the same catalog by Richards et al. shows that the completeness of the sample
is approximately 40%(25%). However, for regions of the sky with very low dust
extinction, like the BCS 23hr field and the Stripe 82 between 0 and 10 degrees
in RA, our completeness is close to 95%, demonstrating that deep GALEX
observations are almost as efficient as multi-wavelength observations at
finding QSO's. GALEX observations thus provide a viable alternate route to QSO
catalogs in sky regions where u-band optical photometry is not available. The
full catalog is available at http://www.ice.csic.es/personal/jimenez/PHOTOZComment: Submitted to ApJ
Rejoinder: challenge and opportunity in the study of ungulate migration amid environmental change
Increasingly, animals that migrate long distances to exploit seasonal habitats must traverse political boundaries capable of altering the very ecological gradients that promote migratory behavior. This transboundary aspect of migration presents many new challenges and opportunities for research and conservation (e.g., Bolger et al. 2008, Taillon et al. 2012). Work to date has often focused on physical barriers to movement (roads, fences, and housing and energy development) that can threaten migratory populations to varying degrees (Holdo et al. 2011, Sawyer et al. 2013). However, even in the absence of conspicuous barriers, political and jurisdictional boundaries can bring dramatic differences in land use and conservation policy. What happens to migratory populations when these boundaries alter the resources and refuges that they seek on their seasonal journeys
Animal migration amid shifting patterns of phenology and predation: lessons from a Yellowstone elk herd
Migration is a striking behavioral strategy by which many animals enhance resource acquisition while reducing predation risk. Historically, the demographic benefits of such movements made migration common, but in many taxa the phenomenon is considered globally threatened. Here we describe a long-term decline in the productivity of elk (Cervus elaphus) that migrate through intact wilderness areas to protected summer ranges inside Yellowstone National Park, USA. We attribute this decline to a long-term reduction in the demographic benefits that ungulates typically gain from migration. Among migratory elk, we observed a 21-year, 70% reduction in recruitment and a 4-year, 19% depression in their pregnancy rate largely caused by infrequent reproduction of females that were young or lactating. In contrast, among resident elk, we have recently observed increasing recruitment and a high rate of pregnancy. Landscape-level changes in habitat quality and predation appear to be responsible for the declining productivity of Yellowstone migrants. From 1989 to 2009, migratory elk experienced an increasing rate and shorter duration of green-up coincident with warmer spring–summer temperatures and reduced spring precipitation, also consistent with observations of an unusually severe drought in the region. Migrants are also now exposed to four times as many grizzly bears (Ursus arctos) and wolves (Canis lupus) as resident elk. Both of these restored predators consume migratory elk calves at high rates in the Yellowstone wilderness but are maintained at low densities via lethal management and human disturbance in the year-round habitats of resident elk. Our findings suggest that large-carnivore recovery and drought, operating simultaneously along an elevation gradient, have disproportionately influenced the demography of migratory elk. Many migratory animals travel large geographic distances between their seasonal ranges. Changes in land use and climate that disparately influence such seasonal ranges may alter the ecological basis of migratory behavior, representing an important challenge for, and a powerful lens into, the ecology and conservation of migratory taxa
Southern Cosmology Survey I: Optical Cluster Detections and Predictions for the Southern Common-Area Millimeter-Wave Experiments
We present first results from the Southern Cosmology Survey, a new
multiwavelength survey of the southern sky coordinated with the Atacama
Cosmology Telescope (ACT), a recently commissioned ground-based mm-band Cosmic
Microwave Background experiment. This article presents a full analysis of
archival optical multi-band imaging data covering an 8 square degree region
near right ascension 23 hours and declination -55 degrees, obtained by the
Blanco 4-m telescope and Mosaic-II camera in late 2005. We describe the
pipeline we have developed to process this large data volume, obtain accurate
photometric redshifts, and detect optical clusters. Our cluster finding process
uses the combination of a matched spatial filter, photometric redshift
probability distributions and richness estimation. We present photometric
redshifts, richness estimates, luminosities, and masses for 8 new
optically-selected clusters with mass greater than 3\times10^{14}M_{\sun} at
redshifts out to 0.7. We also present estimates for the expected
Sunyaev-Zel'dovich effect (SZE) signal from these clusters as specific
predictions for upcoming observations by ACT, the South Pole Telescope and
Atacama Pathfinder Experiment.Comment: 12 pages, 8 figures, accepted in ApJ. Reflects changes from referee
as well as a new Table providing mass estimates and positions for all
clusters in the surve
Southern Cosmology Survey II: Massive Optically-Selected Clusters from 70 square degrees of the SZE Common Survey Area
We present a catalog of 105 rich and massive (M>3\times10^{14}M_{\sun})
optically-selected clusters of galaxies extracted from 70 square-degrees of
public archival griz imaging from the Blanco 4-m telescope acquired over 45
nights between 2005 and 2007. We use the clusters' optically-derived properties
to estimate photometric redshifts, optical luminosities, richness, and masses.
We complement the optical measurements with archival XMM-Newton and ROSAT X-ray
data which provide additional luminosity and mass constraints on a modest
fraction of the cluster sample. Two of our clusters show clear evidence for
central lensing arcs; one of these has a spectacular large-diameter,
nearly-complete Einstein Ring surrounding the brightest cluster galaxy. A
strong motivation for this study is to identify the massive clusters that are
expected to display prominent signals from the Sunyaev-Zeldovich Effect (SZE)
and therefore be detected in the wide-area mm-band surveys being conducted by
both the Atacama Cosmology Telescope and the South Pole Telescope. The optical
sample presented here will be useful for verifying new SZE cluster candidates
from these surveys, for testing the cluster selection function, and for
stacking analyzes of the SZE data.Comment: 13 pages, 7 Figures. Accepted for publication to ApJSS. Full
resolution plots and additional material available at
http://peumo.rutgers.edu/~felipe/e-prints
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