For the first time, we investigate the X-ray/infrared (IR) correlation for star-forming galaxies (SFGs) at z similar to 1, using SPIRE submm data from the recently launched Herschel Space Observatory ...and deep X-ray data from the 2-Ms Chandra Deep Field-North survey. We examine the X-ray/IR correlation in the soft X-ray (SX; 0.5-2 keV) and hard X-ray (HX; 2-10 keV) bands by comparing our z similar to 1 SPIRE-detected SFGs to equivalently IR-luminous (L-IR \textgreater 10(10) L-circle dot) samples in the local/low-redshift Universe. Our results suggest that the X-ray/IR properties of the SPIRE SFGs are on average similar to those of their local counterparts, as we find no evidence for evolution in the L-SX/L-IR and L-HX/L-IR ratios with redshift. We note, however, that at all redshifts, both L-SX/L-IR and L-HX/L-IR are strongly dependent on IR luminosity, with luminous and ultraluminous IR galaxies (LIRGs and ULIRGs; L-IR \textgreater 10(11) L-circle dot) having up to an order of magnitude lower values than normal IR galaxies (L-IR \textless 10(11) L-circle dot). We derive a L-SX-L-IR relation and confirm the applicability of an existing L-HX-L-IR relation for both local and distant LIRGs and ULIRGs, consistent with a scenario where X-ray luminosity is correlated with the star formation rate.
We present the first paper in a series detailing the results of 13CO observations of a ∼1 deg2 region of the giant molecular cloud (GMC) complex associated with the H ii region RCW 106. The 13CO ...observations are also the first stage of a multimolecular line study of the same region. These observations were amongst the first made using the new on-the-fly mapping capability of the Australia Telescope National Facility Mopra Telescope. In the configuration used, the instrument provided a full width at half-maximum (FWHM) beam size of 33 arcsec and a velocity resolution of 0.17 km s−1. The gas emission takes the form of a string of knots, oriented along an axis that extends from the north-west (NW) to the south-east (SE) of the field of the observations, and which is surrounded by a more extended, diffuse emission. We analyse the 2D integrated 13CO emission using the clumpfind algorithm and identify 61 clumps. We compare the gas data in the GMC with the dust data provided by 21-μm Midcourse Space Experiment (MSX) and 1.2-mm Swedish European Southern Observatory Submillimetre Telescope (SEST) images that we both regridded to the cell spacing of the Mopra data and smoothed to the same resolution. The 13CO emission is more diffuse and extended than the dust emission revealed at the latter two wavebands, which both have a much higher contrast between the peaks and the extended emission. From comparison of their centre positions, we find that only ∼50 per cent of the 13CO clump fits to the data are associated with any dust clumps. Using the clump fits, the total local thermodynamic equilibrium gas mass above the 3σ level measured from the molecular data is 2.7 × 105 M⊙, whereas that measured from the smoothed 1.2-mm SEST dust data is 2.2 × 105 M⊙.
Cosmic magnification is due to the weak gravitational lensing of sources in the distant Universe by foreground large-scale structure leading to coherent changes in the observed number density of the ...background sources. Depending on the slope of the background source number counts, cosmic magnification causes a correlation between the background and foreground galaxies, which is unexpected in the absence of lensing if the two populations are spatially disjoint. Previous attempts using submillimetre (submm) sources have been hampered by small number statistics. The large number of sources detected in the Herschel Multi-tiered Extra-galactic Survey (HerMES) Lockman-Spitzer Wide-area Infrared Extragalactic (SWIRE) field enables us to carry out the first robust study of the cross-correlation between submm sources and sources at lower redshifts. Using ancillary data, we compile two low-redshift samples from Sloan Digital Sky Survey (SDSS) and SWIRE with 〈z〉∼ 0.2 and 0.4, respectively, and cross-correlate with two submm samples based on flux density and colour criteria, selecting galaxies preferentially at z∼ 2. We detect cross-correlation on angular scales between ∼1 and 50 arcmin and find clear evidence that this is primarily due to cosmic magnification. A small, but non-negligible signal from intrinsic clustering is likely to be present due to the tails of the redshift distribution of the submm sources overlapping with those of the foreground samples.
We present the results of a gravitational lensing analysis of the bright z s = 2.957 submillimeter galaxy (SMG) HERMES found in the Herschel/SPIRE science demonstration phase data from the Herschel ...Multi-tiered Extragalactic Survey (HerMES) project. The high-resolution imaging available in optical and near-IR channels, along with CO emission obtained with the Plateau de Bure Interferometer, allows us to precisely estimate the intrinsic source extension and hence estimate the total lensing magnification to be Delta *m = 10.9 ? 0.7. We measure the half-light radius R eff of the source in the rest-frame near-UV and V bands that characterize the unobscured light coming from stars and find R eff, * = 2.0 ? 0.1 kpc, in good agreement with recent studies on the SMG population. This lens model is also used to estimate the size of the gas distribution (R eff, gas = 1.1 ? 0.5 kpc) by mapping back in the source plane the CO (J = 5 -> 4) transition line emission. The lens modeling yields a relatively large Einstein radius R Ein = 410 ? 002, corresponding to a deflector velocity dispersion of 483 ? 16 km s--1. This shows that HERMES is lensed by a galaxy group-size dark matter halo at redshift z l ~ 0.6. The projected dark matter contribution largely dominates the mass budget within the Einstein radius with f dm(< R Ein) ~ 80%. This fraction reduces to f dm(< R eff, G1 4.5 kpc) ~ 47% within the effective radius of the main deflecting galaxy of stellar mass M *, G1 = 8.5 ? 1.6 X 1011 M . At this smaller scale the dark matter fraction is consistent with results already found for massive lensing ellipticals at z ~ 0.2 from the Sloan Lens ACS Survey.
The role of cardiac glycosides in treating patients with chronic heart failure and normal sinus rhythm remains controversial. We studied the effect of digoxin on mortality and hospitalization in a ...randomized, double-blind clinical trial.
In the main trial, patients with a left ventricular ejection fraction of 0.45 or less were randomly assigned to digoxin (3397 patients) or placebo (3403 patients) in addition to diuretics and angiotensin-converting-enzyme inhibitors (median dose of digoxin, 0.25 mg per day; average follow-up, 37 months). In an ancillary trial of patients with ejection fractions greater than 0.45, 492 patients were randomly assigned to digoxin and 496 to placebo.
In the main trial, mortality was unaffected. There were 1181 deaths (34.8 percent) with digoxin and 1194 deaths (35.1 percent) with placebo (risk ratio when digoxin was compared with placebo, 0.99; 95 percent confidence interval, 0.91 to 1.07; P=0.80). In the digoxin group, there was a trend toward a decrease in the risk of death attributed to worsening heart failure (risk ratio, 0.88; 95 percent confidence interval, 0.77 to 1.01; P=0.06). There were 6 percent fewer hospitalizations overall in that group than in the placebo group, and fewer patients were hospitalized for worsening heart failure (26.8 percent vs. 34.7 percent; risk ratio, 0.72; 95 percent confidence interval, 0.66 to 0.79; P<0.001). In the ancillary trial, the findings regarding the primary combined outcome of death or hospitalization due to worsening heart failure were consistent with the results of the main trial.
Digoxin did not reduce overall mortality, but it reduced the rate of hospitalization both overall and for worsening heart failure. These findings define more precisely the role of digoxin in the management of chronic heart failure.
High voltage power management applications often require 50V to 100V operation. These circuits are implemented in a BiCMOS processes and support both low voltage (5-15V) and high voltage devices. In ...these applications the high voltage PMOS (HV-PMOS) must operate at high currents, voltages (e.g. 80V) and temperatures (150/spl deg/C) while sustaining a drain breakdown voltage in excess of the device operating voltage. This paper examines an HV-PMOS failure mode identified during device qualification and high temperature operational life. This paper presents data on a new PMOS failure mechanism termed "drain breakdown voltage walk-in" not yet discussed in the literature.
Metal speciation. Effects on aquatic toxicity Allen, Herbert E; Hall, Richard H; Brisbin, Thomas D
Environmental science & technology,
1980-Apr-01, Letnik:
14, Številka:
4
Journal Article
Recenzirano
The authors report the results of experiments which demonstrate that the toxicity of trace metals to algae depends, not on the total soluble metal concentration, but on the concentration of free ...metal xon.
The object of this study is to experimentally validate the usefulness of the multi-RESURF and diluted junction methodology to improve the electrical characteristics of lateral extended drain voltage ...NMOS. Electrical and hot carrier degradation characteristics are discussed. Significant improvement in the device electrical characteristics is shown, while hot carrier degradation was found to be the limiting factor.
For PMOSFET devices NBTI is a serious reliability concern. Because of recovery effects careful stress and measurement methods must be used to determine threshold voltage degradation. These methods ...assume that mobility and subthreshold slope degradation are minimal. Recent papers have pointed out that this assumption may not be valid. This paper discusses for the first time a unique fast switching NBTI measurement technique that alternates between two V GS measurement conditions to determine the subthreshold slope vs. stress time. From these measurements the effect of subthreshold slope degradation on V T degradation can be accurately determined and results compared to the standard techniques. In, addition, this work also introduces an improved NBTI fast switching test methodology to complement the pending NBTI JEDEC testing standard.
Smart power management applications often require operation in the 20–30
V range. These applications combine a high performance BiCMOS process with a power lateral DMOS (LDMOS) driver. To obtain high ...drive current density and minimal on-resistance (
R
dson), LDMOS devices are implemented in transistor arrays. Because of the high voltages and currents applied to these devices hot carrier degradation is a real reliability concern. This paper discusses several aspects of N-LDMOS hot carrier reliability including measurement techniques, degradation mechanism, and the effect of both one-dimensional (1-D) and two-dimensional (2-D) layout effects on the hot carrier degradation behavior of these devices. This paper focuses on device layout optimization rather than process changes since layout optimization has the advantage of improving performance without impacting other supported devices.
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