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Children with CHD and acquired heart disease have unique, high-risk physiology. They may have a higher risk of adverse tracheal-intubation-associated events, as compared with children with non-cardiac disease.
Materials and methods
We sought to evaluate the occurrence of adverse tracheal-intubation-associated events in children with cardiac disease compared to children with non-cardiac disease. A retrospective analysis of tracheal intubations from 38 international paediatric ICUs was performed using the National Emergency Airway Registry for Children (NEAR4KIDS) quality improvement registry. The primary outcome was the occurrence of any tracheal-intubation-associated event. Secondary outcomes included the occurrence of severe tracheal-intubation-associated events, multiple intubation attempts, and oxygen desaturation.
A total of 8851 intubations were reported between July, 2012 and March, 2016. Cardiac patients were younger, more likely to have haemodynamic instability, and less likely to have respiratory failure as an indication. The overall frequency of tracheal-intubation-associated events was not different (cardiac: 17% versus non-cardiac: 16%, p=0.13), nor was the rate of severe tracheal-intubation-associated events (cardiac: 7% versus non-cardiac: 6%, p=0.11). Tracheal-intubation-associated cardiac arrest occurred more often in cardiac patients (2.80 versus 1.28%; p<0.001), even after adjusting for patient and provider differences (adjusted odds ratio 1.79; p=0.03). Multiple intubation attempts occurred less often in cardiac patients (p=0.04), and oxygen desaturations occurred more often, even after excluding patients with cyanotic heart disease.
The overall incidence of adverse tracheal-intubation-associated events in cardiac patients was not different from that in non-cardiac patients. However, the presence of a cardiac diagnosis was associated with a higher occurrence of both tracheal-intubation-associated cardiac arrest and oxygen desaturation.
Between 1013 - 1017 Hz the continua of all PG quasars can be described in the most general terms by a model consisting of two broad peaks of thermal radiation. There is no evidence for energetically significant nonthermal radiation in this frequency range in the continua of the PG quasars. We have compiled continuum observations for PG quasars from 6 cm to 2 KeV, including IRAS data for all these objects and new ground-based infrared data at 10 μm for many of these quasars. Sixty-three of the PG quasars were detected by IRAS in at least one band. The overall energy distributions for these sixty-three PG quasars are shown in Figure 1.
We report some preliminary results from the Massachusetts - Stony Brook CO survey of the first galactic quadrant using the 14-meter millimeterwave telescope of the Five College Radio Astronomy Observatory. The survey contains approximately 50 000 observations spaced every 3 arcminutes in 1 and b between longitudes 0° and 90° and latitudes −1° and 1°. We have mapped emission from giant molecular clouds (GMC) which we identified, in earlier more limited strip surveys of the galactic plane (Solomon, Sanders and Scoville 1979; Sanders 1981), on size scales from a few parsecs to hundreds of parsecs, in order to determine the degree of clustering and organization into large-scale features. In addition to the characteristic size of 20 – 60 pc for individual GMC, we find clustering of clouds on a scale of from 100 to 300 pc.
CO emission has been detected from 75 bright infrared galaxies with CZ = 2 000 – 16 000 km/s. These include the most distant and the most luminous galaxies (Arp 55, IR 1713+63) yet detected in CO. All of these galaxies are rich in molecular gas with Mtotal (H2) = 2 × 109 −6x1010 M⊙, and they have a strong far-infrared excess, with LFIR/LB = 2-40 and LFIR (40-400μ) = 1010 – 3 × 1012 L⊙. The primary luminosity source appears to be star formation in molecular clouds. A strong correlation is found between the FIR and 21-cm continuum flux, implying that the IMF is independent of the star formation rate. The ratio LFIR/M(H2) provides a measure of the current rate of star-formation, which is found to be a factor 3-20 larger in these galaxies than for the ensemble of molecular clouds in the Milky Way. VLA maps plus a few high resolution (14″-30″) CO (1-0) and CO (2-1) maps suggest that most of the luminosity comes from core regions 1-3 kpc in size. The abnormal concentration of molecular gas in these galactic cores is presumably the result of a collision or strong interaction with a nearby companion.
Recent millimeterwave observations of CO emission from ultraluminous infrared galaxies (Lir > 1012 L) and quasars suggest that abundant supplies of molecular gas may be a common property of both types of object. Current published CO detections are summarized, and the possibility of an evolutionary connection between infrared galaxies and quasars is discussed.
Arp 299 (Mrk 171), is an interacting system at 42 Mpc, comprising the galaxies IC 694 and NGC 3690. Interferometric CO maps at 6″ resolution (Sargent et al. 1987) showed compact molecular condensations at the nucleus of IC694 and in the overlap region of the galaxy disks [positions A and C – C in the terminology of Gehrz, Sramek, and Weedman (1983)].
Galactic background radiation has been observed in the 78-111 eV Be band using 5000 Å beryllium filters in front of a thin-window proportional counter collimated to a 15° full width at half maximum field of view. Be band data have been analyzed from two sounding rocket flights (Bloch et al. 1986, Juda 1988) that viewed seventeen different directions distributed over the northern galactic hemisphere. In Figure 1 the pointing directions of the two flights are indicated on a map from McCammon et al. (1983) of the 130-188 eV B band count rate.
This paper briefly describes the principle of operation and science goals of the AMANDA high energy neutrino telescope located at the South Pole, Antarctica. Results from an earlier phase of the telescope, called AMANDA-BIO, demonstrate both reliable operation and the broad astrophysical reach of this device, which includes searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, Gamma-Ray Bursts and diffuse sources. The predicted sensitivity and angular resolution of the telescope were confirmed by studies of atmospheric muon and neutrino backgrounds. We also report on the status of the analysis from AMANDA-II, a larger version with far greater capabilities. At this stage of analysis, details of the ice properties and other systematic uncertainties of the AMANDA-II telescope are under study, but we have made progress toward critical science objectives. In particular, we present the first preliminary flux limits from AMANDA-II on the search for continuous emission from astrophysical point sources, and report on the search for correlated neutrino emission from Gamma Ray Bursts detected by BATSE before decommissioning in May 2000. During the next two years, we expect to exploit the full potential of AMANDA-II with the installation of a new data acquisition system that records full waveforms from the in-ice optical sensors.
Infrared observations of complete samples of active galactic nuclei (AGN) have shown that a substantial fraction of their bolometric luminosity is emitted at wavelengths ˜8–1000μm. In radio-loud and Blazar-like objects much of this emission appears to be direct non-thermal synchrotron radiation. However, in the much larger numbers of radio-quiet AGN it is now clear that thermal dust emission is responsible for the bulk of radiation from the near-infrared through submillimeter wavelengths. Luminous infrared-selected AGN are often surrounded by powerful nuclear starbursts, both of which appear to be fueled by enormous supplies of molecular gas and dust funneled into the nuclear region during the strong interaction/merger of gas rich disks. All-sky surveys in the infrared show that luminous infrared AGN are at least as numerous as optically-selected AGN of comparable bolometric luminosity, suggesting that AGN may spend a substantial fraction of their lifetime in a dust-enshrouded phase. The space density of luminous infrared AGN at high redshift may be sufficient to account for much of the X-Ray background, and for a substantial fraction of the far-infrared background as well. These objects plausibly represent a major epoch in the formation of spheroids and massive black holes (MBH).
We present the characteristics of far-infrared (FIR) brightness fluctuations at 90 μm and 170 μm in the Lockman Hole, which were surveyed with the ISOPHOT instrument aboard the Infrared Space Observatory (ISO), and give constraints on the galaxy number counts down to 30 mJy at 90 μm and 50 mJy at 170 μm. The fluctuation power spectra of the FIR images are not dominated by IR cirrus, and are instead most likely due to star-forming galaxies. This analysis indicates the existence of strong evolution in the counts. Especially at 90 μm, the source density is much larger than that expected from the currently available galaxy count models. The galaxies responsible for the fluctuations also significantly contribute to the cosmic infrared background radiation recently derived from an analysis of the COBE data.
This conference on AGN Surveys has proved to be a significant milestone in our understanding of the redshift distribution of optically selected QSOs, and in our initial understanding of the cosmic distribution of AGN from the first far-infrared and X-ray deep fields. It has also set the stage for continuing debates concerning the multiwave-length properties of AGN, the cosmological distribution of “obscured” AGN, and the “orientation versus evolution” debate on the nature of the sources discovered at different wavelengths. Much of this debate could have been anticipated from previous studies of the complete samples of optically-selected AGN provided to us by the pioneering work carried out by the staff of the Byurakan Astronomical Observatory over the past 40 years.
High-precision analysis using accelerator mass spectrometry (AMS) was performed upon known-age Holocene and modern, pre-bomb coral samples to generate a marine reservoir age correction value (ΔR) for the Houtman-Abrolhos Archipelago (28.7°S, 113.8°E) off the Western Australian coast. The mean ΔR value calculated for the Abrolhos Islands, 54 ± 30 yr (1 σ) agrees well with regional ΔR values for Leeuwin Current source waters (N-NW Australia-Java) of 60 ± 38 yr. The Abrolhos Islands show little variation with ΔR values of the northwestern and north Australian coast, underlining the dominance of the more equilibrated western Pacific-derived waters of the Leeuwin Current over local upwelling. The Abrolhos Islands ΔR values have remained stable over the last 2896 cal yr BP, being also attributed to the Leeuwin Current and the El Niño Southern Oscillation (ENSO) signal during this period. Expected future trends will be a strengthening of the teleconnection of the Abrolhos Islands to the climatic patterns of the equatorial Pacific via enhanced ENSO and global warming activity strengthening the Leeuwin Current. The possible effect upon the trend of future ΔR values may be to maintain similar values and an increase in stability. However, warming trends of global climate change may cause increasing dissimilarity of ΔR values due to the effects of increasing heat stress upon lower-latitude coral communities.
The majority of infrared active galaxies (ffir/fb ≥ 2) have molecular to atomic mass fractions in the range of 0.5 to 2.0. Among the galaxies with the higher infrared excesses there are spectacular cases of HI deficient systems, where less than 15% of the total mass of interstellar gas is in atomic form. The optical morphology of luminous infrared galaxies suggest that the overall mass fractions of molecular to atomic gas, and the infrared luminosities per nucleon of interstellar gas are enhanced during galaxy-galaxy interactions.
We have mapped an extensive molecular cloud in Perseus in the 115 GHz line of 12CO. Observations were made every 10′ in right ascension and declination over most of the cloud, and every 2′ in the regions of most intense emission, near the open cluster IC 348 and near the reflection nebula NGC 1333. We also obtained 110 GHz 13CO data every 2′ in the latter regions, as well as every 10′ in several long strips across the cloud. A total of 812 positions were observed in 12CO, and 200 in 13CO. This work was done using the 5 m antenna of the Millimeter Wave Observatory of the University of Texas. The half-power beam size was 2!6.
Observations of CO emission at ℓ=0 to 70°, |b| ≤ 1° are analyzed to give a map of the molecular cloud distribution in the galaxy as viewed from the galactic pole. From the fact that this distribution shows no obvious spiral pattern we conclude that the giant molecular clouds sampled in the CO line are situated in both arm and interarm regions and they must last more than 108 years. A similar age estimate is deduced from the large mass fraction of H2 in the interstellar medium in the interior of the galaxy. An implication of this longevity is that the great masses of these clouds may be accumulated through cloud-cloud collisions of originally smaller clouds.
Millimeter wave observations of emission from the CO molecule have become, over the past eight years, the dominant method for determining the physical properties of dense interstellar clouds, composed primarily of molecular hydrogen and for exploring the structure and kinematics of the galactic disk. In this paper we briefly review the CO survey results in the literature (Section 2) and then present new results (Section 3-7) of an extensive 13CO and 12CO survey of the galactic distribution, size, mass and age of molecular clouds. The interpretation of this survey leads to a new picture of the interstellar medium dominated by very massive stable long-lived clouds which we refer to as Giant Molecular Clouds. We find that Giant Molecular Clouds (GMC's) with M = 105–3 × 106M⊙ are a major constituent of the galactic disk, the dominant component of the interstellar medium in the galaxy interior to the sun and the most massive objects in the galaxy. We find that the interstellar medium and star formation are dominated by massive gravitationally bound clouds in which stars and associations are forming but at a very low rate in comparison to the free fall time. The galactic distribution of the molecules as traced by CO emission is interpreted as the distribution of GMC's. As the most massive objects in the galaxy they are also basic to the dynamics of the disk.