8,706 research outputs found
Cobalt complexes: correlation of redox potential with effectivity as oxygenation catalysts
The redox potential of a series of cobalt(II) chelates correlates with their properties as either oxygen carriers or phosphine oxidation catalysts
An Unexpectedly Swift Rise in the Gamma-ray Burst Rate
The association of long gamma-ray bursts with supernovae naturally suggests
that the cosmic GRB rate should trace the star formation history. Finding
otherwise would provide important clues concerning these rare, curious
phenomena. Using a new estimate of Swift GRB energetics to construct a sample
of 36 luminous GRBs with redshifts in the range z=0-4, we find evidence of
enhanced evolution in the GRB rate, with ~4 times as many GRBs observed at z~4
than expected from star formation measurements. This direct and empirical
demonstration of needed additional evolution is a new result. It is consistent
with theoretical expectations from metallicity effects, but other causes remain
possible, and we consider them systematically.Comment: 4 pages, 4 figures; minor changes to agree with published versio
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Inhibition of adenovirus serotype 14 infection by octadecyloxyethyl esters of (S)-[(3-hydroxy-2-phosphonomethoxy)propyl]- nucleosides in vitro.
On September 22, 2008, a physician on Prince of Wales Island, Alaska, notified the Alaska Department of Health and Social Services (ADHSS) of an unusually high number of adult patients with recently diagnosed pneumonia (n = 10), including three persons who required hospitalization and one who died. ADHSS and CDC conducted an investigation to determine the cause and distribution of the outbreak, identify risk factors for hospitalization, and implement control measures. This report summarizes the results of that investigation, which found that the outbreak was caused by adenovirus 14 (Ad14), an emerging adenovirus serotype in the United States that is associated with a higher rate of severe illness compared with other adenoviruses. Among the 46 cases identified in the outbreak from September 1 through October 27, 2008, the most frequently observed characteristics included the following: male (70%), Alaska Native (61%), underlying pulmonary disease (44%), aged > or = 65 years (26%), and current smoker (48%). Patients aged > or = 65 years had a fivefold increased risk for hospitalization. The most commonly reported symptoms were cough (100%), shortness of breath (87%), and fever (74%). Of the 11 hospitalized patients, three required intensive care, and one required mechanical ventilation. One death was reported. Ad14 isolates obtained during the outbreak were identical genetically to those in recent community-acquired outbreaks in the United States which suggests the emergence of a new, and possibly more virulent Ad14 variant. Clinicians should consider Ad14 infection in the differential diagnosis for patients with community-acquired pneumonia, particularly when unexplained clusters of severe respiratory infections are detected
Resistance training for rehabilitation after burn injury: A systematic literature review and meta-analysis
Background/aim: Resistance training is beneficial for rehabilitation in many clinical conditions, though this has not been systematically reviewed in burns. The objective was to determine the effectiveness of resistance training on muscle strength, lean mass, function, quality of life and pain, in children and adults after burn injury.
Methods: Medline & EMBASE, PubMed, CINAHL and CENTRAL were searched from inception to October 2016. Studies were identified that implemented resistance training in rehabilitation. Data were combined and included in meta-analyses for muscle strength and lean mass. Otherwise, narrative analysis was completed. The quality of evidence for each outcome was summarised and rated using the GRADE framework.
Results: Eleven studies matched our inclusion criteria. Primary analysis did not demonstrate significant improvements for increasing muscle strength (SMD 0.74, 95% CI _0.02 to 1.50, p=0.06). Sensitivity analysis to correct an apparent anomaly in published data suggested a positive effect (SMD 0.37, 95% CI 0.08–0.65, p=0.01). Psychological quality of life demonstrated benefit from training (MD=25.3, 95% CI 3.94–49.7). All studies were rated as having high risk of bias. The quality of the evidence was rated as low or very low.
Conclusion: Further research with robust methodology is recommended to assess the potential benefit suggested in this review
Planetary astronomy
The authors profile the field of astronomy, identify some of the key scientific questions that can be addressed during the decade of the 1990's, and recommend several facilities that are critically important for answering these questions. Scientific opportunities for the 1990' are discussed. Areas discussed include protoplanetary disks, an inventory of the solar system, primitive material in the solar system, the dynamics of planetary atmospheres, planetary rings and ring dynamics, the composition and structure of the atmospheres of giant planets, the volcanoes of IO, and the mineralogy of the Martian surface. Critical technology developments, proposed projects and facilities, and recommendations for research and facilities are discussed
Imaging the cool gas, dust, star formation, and AGN in the first galaxies
When, and how, did the first galaxies and supermassive black holes (SMBH)
form, and how did they reionization the Universe? First galaxy formation and
cosmic reionization are among the last frontiers in studies of cosmic structure
formation. We delineate the detailed astrophysical probes of early galaxy and
SMBH formation afforded by observations at centimeter through submillimeter
wavelengths. These observations include studies of the molecular gas (= the
fuel for star formation in galaxies), atomic fine structure lines (= the
dominant ISM gas coolant), thermal dust continuum emission (= an ideal star
formation rate estimator), and radio continuum emission from star formation and
relativistic jets. High resolution spectroscopic imaging can be used to study
galaxy dynamics and star formation on sub-kpc scales. These cm and mm
observations are the necessary compliment to near-IR observations, which probe
the stars and ionized gas, and X-ray observations, which reveal the AGN.
Together, a suite of revolutionary observatories planned for the next decade
from centimeter to X-ray wavelengths will provide the requisite panchromatic
view of the complex processes involved in the formation of the first generation
of galaxies and SMBHs, and cosmic reionization.Comment: 8 pages total. White paper submitted to the Astro 2010 Decadal Surve
A Mandated Minimum Competency Testing Program and Its Impact on Learning Disabled Students: Curricular Validity and Comparative Performances
This research was published by the KU Center for Research on Learning, formerly known as the University of Kansas Institute for Research in Learning Disabilities.In this study, LD specialists, regular class teachers, and parents of LD students judged that the objectives of the Kansas Minimum Competency Specifications prescribed for nonhandicapped students were applicable to LD students. In addition, the Kansas Minimal Competency Test was administered to LD students under standard and oral conditions. Results showed that they did not perform as well as their nonhandicapped peers at any of the five grade levels. The test was then administered under two modified conditions. Learning disabled students' performance on some objectives at every grade level was not improved by either administering items orally or administering the test one grade level above that designated for nonhandicapped students
Herschel Far-Infrared and Sub-millimeter Photometry for the KINGFISH Sample of Nearby Galaxies
New far-infrared and sub-millimeter photometry from the Herschel Space
Observatory is presented for 61 nearby galaxies from the Key Insights on Nearby
Galaxies: A Far-Infrared Survey with Herschel (KINGFISH) sample. The
spatially-integrated fluxes are largely consistent with expectations based on
Spitzer far-infrared photometry and extrapolations to longer wavelengths using
popular dust emission models. Dwarf irregular galaxies are notable exceptions,
as already noted by other authors, as their 500um emission shows evidence for a
sub-millimeter excess. In addition, the fraction of dust heating attributed to
intense radiation fields associated with photo-dissociation regions is found to
be (21+/-4)% larger when Herschel data are included in the analysis. Dust
masses obtained from the dust emission models of Draine & Li are found to be on
average nearly a factor of two higher than those based on single-temperature
modified blackbodies, as single blackbody curves do not capture the full range
of dust temperatures inherent to any galaxy. The discrepancy is largest for
galaxies exhibiting the coolest far-infrared colors.Comment: Accepted for publication in Ap
Near-Infrared Spectral Geometric Albedos of Charon and Pluto: Constraints on Charon's Surface Composition
The spectral geometric albedos of Charon and Pluto are derived at near-infrared wavelengths (1.4-2.5 jAm) from measurements obtained in 1987. Comparisons of these to theoretical calculations are used to place constraints on the identity and relative abundances of surface ices on Charon. These compari- sons suggest that widespread regions of pure CH4 ice do not occur on Charon and that if CH4 is abundant on Charon then it is large grained (-5 mm) and is likely mixed at the granular level with H20 ice, and possibly C02 ice
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