5,065 research outputs found
An Early Bronze Age 'dagger grave' from Rameldry Farm, near Kingskettle, Fife
In February 2000, ploughing disturbed the capstone of a cist, located on the side of a prominent knowe at Rameldry Farm, near Kingskettle in central Fife. Excavation by Headland Archaeology Ltd on behalf of Historic Scotland revealed a short cist which contained the crouched inhumation of a man aged 40-50, who had suffered from arthritis, some tooth loss and possibly Paget's Disease. He had been buried wearing a garment adorned with six V-pelforated buttons. Five of these are of Whitby jet (including one with unique decoration including inlaid tin); the sixth is of the mineral lizardite, and has an enigmatic coating, possibly a glaze. Behind his shoulder was a dagger, of 'Milston type (East Kennet variant) it had had a fancy horn hilt and a scabbard lined with animal skin. The scabbard yielded two A MS radiocarbon dates, with a mean value of 2280-1970 cal Bc at 2
Economic evaluation of the routine use of echocardiography versus natriuretic peptide and ECG-targeted echocardiography in the diagnosis of heart failure
Objectives: To investigate the most efficient use of echocardiography and natriuretic peptide testing in the diagnosis of heart failure.
Design: An economic model comparing two strategies: (A) provide echocardiography and electrocardiogram (ECG) for all individuals who present to a GP with symptoms that may be due to heart failure; (B) carry out B-type natriuretic peptide (BNP) blood test and ECG on all such individuals and provide echocardiography only where an abnormality is detected in one of more of these tests.
Setting: Primary care in the UK NHS.
Subjects: Individuals who present to a GP with new symptoms of heart failure.
Main outcome measures: Cost per life year gained.
Results: Baseline cost per life year gained by strategy A compared with strategy B is £3,987.
Conclusions: Immediate echocardiography is the most cost-effective option. Where echocardiography is a scarce resource, efficient use can be obtained by using BNP and ECG tests to identify patients most likely to have heart failure
The Number Density of Intermediate and High Luminosity Active Galactic Nuclei at z~2-3
We use the combination of the 2 Ms Chandra X-ray image, new J and H band
images, and the Spitzer IRAC and MIPS images of the Chandra Deep Field-North to
obtain high spectroscopic and photometric redshift completeness of high and
intermediate X-ray luminosity sources in the redshift interval z=2-3. We
measure the number densities of z=2-3 active galactic nuclei (AGNs) and
broad-line AGNs in the rest-frame 2-8 keV luminosity intervals 10^44-10^45 and
10^43-10^44 ergs/s and compare with previous lower redshift results. We confirm
a decline in the number densities of intermediate-luminosity sources at z>1. We
also measure the number density of z=2-3 AGNs in the luminosity interval
10^43-10^44.5 ergs/s and compare with previous low and high-redshift results.
Again, we find a decline in the number densities at z>1. In both cases, we can
rule out the hypothesis that the number densities remain flat to z=2-3 at above
the 5-sigma level.Comment: 8 pages, Accepted by The Astrophysical Journal (scheduled for 10 Dec
2005
Star Formation History since z = 1.5 as Inferred from Rest-Frame Ultaviolet Luminosity Density Evolution
We investigate the evolution of the universal rest-frame ultraviolet
luminosity density from z = 1.5 to the present. We analyze an extensive sample
of multicolor data (U', B, V = 24.5) plus spectroscopic redshifts from the
Hawaii Survey Fields and the Hubble Deep Field. Our multicolor data allow us to
select our sample in the rest-frame ultraviolet (2500 angstrom) over the entire
redshift range to z = 1.5. We conclude that the evolution in the luminosity
density is a function of the form (1+z)^{1.7\pm1.0} for a flat lambda cosmology
and (1+z)^{2.4\pm1.0} for an Einstein-de Sitter cosmology.Comment: 12 pages, 7 figs, 5 tables, submitted to A
A Flux-Limited Sample of z~1 Ly-alpha Emitting Galaxies in the CDFS
We describe a method for obtaining a flux-limited sample of Ly-alpha emitters
from GALEX grism data. We show that the multiple GALEX grism images can be
converted into a three-dimensional (two spatial axes and one wavelength axis)
data cube. The wavelength slices may then be treated as narrowband images and
searched for emission-line galaxies. For the GALEX NUV grism data, the method
provides a Ly-alpha flux-limited sample over the redshift range z=0.67-1.16. We
test the method on the Chandra Deep Field South field, where we find 28
Ly-alpha emitters with faint continuum magnitudes (NUV>22) that are not present
in the GALEX pipeline sample. We measure the completeness by adding artificial
emitters and measuring the fraction recovered. We find that we have an 80%
completeness above a Ly-alpha flux of 10^-15 erg/cm^2/s. We use the UV spectra
and the available X-ray data and optical spectra to estimate the fraction of
active galactic nuclei in the selection. We report the first detection of a
giant Ly-alpha blob at z<1, though we find that these objects are much less
common at z=1 than at z=3. Finally, we compute limits on the z~1 Ly-alpha
luminosity function and confirm that there is a dramatic evolution in the
luminosity function over the redshift range z=0-1.Comment: 18 pages, in press at The Astrophysical Journa
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