13,433 research outputs found
Children with severe malnutrition: can those at highest risk of death be identified with the WHO protocol?
Background With strict adherence to international recommended treatment guidelines, the case fatality for severe malnutrition ought to be less than 5%. In African hospitals, fatality rates of 20% are common and are often attributed to poor training and faulty case management. Improving outcome will depend upon the identification of those at greatest risk and targeting limited health resources. We retrospectively examined the major risk factors associated with early (<48 h) and late in-hospital death in children with severe malnutrition with the aim of identifying admission features that could distinguish a high-risk group in relation to the World Health Organization (WHO) guidelines. Methods and Findings Of 920 children in the study, 176 (19%) died, with 59 (33%) deaths occurring within 48 h of admission. Bacteraemia complicated 27% of all deaths: 52% died before 48 h despite 85% in vitro antibiotic susceptibility of cultured organisms. The sensitivity, specificity, and likelihood ratio of the WHO-recommended ādanger signsā (lethargy, hypothermia, or hypoglycaemia) to predict early mortality was 52%, 84%, and 3.4% (95% confidence interval [CI] = 2.2 to 5.1), respectively. In addition, four bedside features were associated with early case fatality: bradycardia, capillary refill time greater than 2 s, weak pulse volume, and impaired consciousness level; the presence of two or more features was associated with an odds ratio of 9.6 (95% CI = 4.8 to 19) for early fatality (p < 0.0001). Conversely, the group of children without any of these seven features, or signs of dehydration, severe acidosis, or electrolyte derangements, had a low fatality (7%). Conclusions Formal assessment of these features as emergency signs to improve triage and to rationalize manpower resources toward the high-risk groups is required. In addition, basic clinical research is necessary to identify and test appropriate supportive treatments
Surveying the solar system by measuring angles and times: from the solar density to the gravitational constant
A surprisingly large amount of information on our solar system can be gained
from simple measurements of the apparent angular diameters of the sun and the
moon. This information includes the average density of the sun, the distance
between earth and moon, the radius of the moon, and the gravitational constant.
In this note it is described how these and other quantities can be obtained by
simple earthbound measurements of angles and times only, without using any
explicit information on distances between celestial bodies. The pedagogical and
historical aspects of these results are also discussed briefly.Comment: 12 pges, one figur
Completed cohomology of Shimura curves and a p-adic Jacquet-Langlands correspondence
We study indefinite quaternion algebras over totally real fields F, and give
an example of a cohomological construction of p-adic Jacquet-Langlands
functoriality using completed cohomology. We also study the (tame) levels of
p-adic automorphic forms on these quaternion algebras and give an analogue of
Mazur's `level lowering' principle.Comment: Updated version. Contains some minor corrections compared to the
published versio
A Search for Additional Bodies in the GJ 1132 Planetary System from 21 Ground-based Transits and a 100 Hour Spitzer Campaign
We present the results of a search for additional bodies in the GJ 1132
system through two methods: photometric transits and transit timing variations
of the known planet. We collected 21 transit observations of GJ 1132b with the
MEarth-South array since 2015. We obtained 100 near-continuous hours of
observations with the Space Telescope, including two transits of GJ
1132b and spanning 60\% of the orbital phase of the maximum period at which
bodies coplanar with GJ 1132b would pass in front of the star. We exclude
transits of additional Mars-sized bodies, such as a second planet or a moon,
with a confidence of 99.7\%. When we combine the mass estimate of the star
(obtained from its parallax and apparent band magnitude) with the stellar
density inferred from our high-cadence light curve (assuming zero
eccentricity), we measure the stellar radius of GJ 1132 to be
, and we refine the radius measurement of
GJ 1132b to . Combined with HARPS RV measurements, we
determine the density of GJ 1132b to be \ g cm, with the
mass determination dominating this uncertainty. We refine the ephemeris of the
system and find no evidence for transit timing variations, which would be
expected if there was a second planet near an orbital resonance with GJ 1132b.Comment: 29 pages, 4 Tables, 8 Figures, Submitted to ApJ. Comments welcom
Is There a Fundamental Line for Disk Galaxies?
We show that there are strong local correlations between metallicity, surface
brightness, and dynamical mass-to-light ratio within M33, analogous to the
fundamental line of dwarf galaxies identified by Prada & Burkert (2002). Using
near-infrared imaging from 2MASS, the published rotation curve of M33, and
literature measurements of the metallicities of HII regions and supergiant
stars, we demonstrate that these correlations hold for points at radial
distances between 140 pc and 6.2 kpc from the center of the galaxy. At a given
metallicity or surface brightness, M33 has a mass-to-light ratio approximately
four times as large as the Local Group dwarf galaxies; other than this constant
offset, we see broad agreement between the M33 and dwarf galaxy data. We use
analytical arguments to show that at least two of the three fundamental line
correlations are basic properties of disk galaxies that can be derived from
very general assumptions. We investigate the effect of supernova feedback on
the fundamental line with numerical models and conclude that while feedback
clearly controls the scatter in the fundamental line, it is not needed to
create the fundamental line itself, in agreement with our analytical
calculations. We also compare the M33 data with measurements of a simulated
disk galaxy, finding that the simulation reproduces the trends in the data
correctly and matches the fundamental line, although the metallicity of the
simulated galaxy is too high, and the surface brightness is lower than that of
M33.Comment: 14 pages, 14 figures (5 in color). Accepted for publication in Ap
The potential therapeutic effects of creatine supplementation on body composition and muscle function in cancer
Low muscle mass in individuals with cancer has a profound impact on quality of life and independence and is associated with greater treatment toxicity and poorer prognosis. Exercise interventions are regularly being investigated as a means to ameliorate treatment-related adverse effects, and nutritional/supplementation strategies to augment adaptations to exercise are highly valuable. Creatine (Cr) is a naturally-occurring substance in the human body that plays a critical role in energy provision during muscle contraction. Given the beneficial effects of Cr supplementation on lean body mass, strength, and physical function in a variety of clinical populations, there is therapeutic potential in individuals with cancer at heightened risk for muscle loss. Here, we provide an overview of Cr physiology, summarize the evidence on the use of Cr supplementation in various aging/clinical populations, explore mechanisms of action, and provide perspectives on the potential therapeutic role of Cr in the exercise oncology setting
High Resolution X-Ray Imaging of the Center of IC342
We presented the result of a high resolution (FWHM~0.5'') 12 ks Chandra HRC-I
observation of the starburst galaxy IC342 taken on 2 April 2006. We identified
23 X-ray sources within the central 30' x 30' region of IC342. Our HRC-I
observation resolved the historical Ultraluminous X-ray sources (ULX), X3, near
the nucleus into 2 sources, namely C12 and C13, for the first time. The
brighter source C12, with L(0.08-10keV)=(6.66\pm0.45)\times10^{38}ergs^-1, was
spatially extended (~82 pc x 127 pc). From the astrometric registration of the
X-ray image, C12 was at R.A.=03h:46m:48.43s, decl.=+68d05m47.45s, and was
closer to the nucleus than C13. Thus we concluded that source was not an ULX
and must instead be associated with the nucleus. The fainter source C13, with
L(0.08-10keV)=(5.1\pm1.4) x 10^{37}ergs^-1 was consistent with a point source
and located $6.51'' at P.A. 240 degree of C12.
We also analyzed astrometrically corrected optical Hubble Space Telescope and
radio Very Large Array images, a comparison with the X-ray image showed
similarities in their morphologies. Regions of star formation within the
central region of IC342 were clearly visible in HST H alpha image and this was
the region where 3 optical star clusters and correspondingly our detected X-ray
source C12 were observed. We found that a predicted X-ray emission from
starburst was very close to the observed X-ray luminosity of C12, suggesting
that nuclear X-ray emission in IC342 was dominated by starburst. Furthermore,
we discussed the possibility of AGN in the nucleus of IC342. Although our data
was not enough to give a firm existence of an AGN, it could not be discarded.Comment: 29 page, 8 figures, accepted by Ap
Bar imprints on the inner gas kinematics of M33
We present measurements of the stellar and gaseous velocities in the central
5' of the Local Group spiral M33. The data were obtained with the ARC 3.5m
telescope. Blue and red spectra with resolutions from 2 to 4\AA covering the
principal gaseous emission and stellar absorption lines were obtained along the
major and minor axes and six other position angles. The observed radial
velocities of the ionized gas along the photometric major axis of M33 remain
flat at ~22 km s^{-1} all the way into the center, while the stellar velocities
show a gradual rise from zero to 22 km s^{-1} over that same region. The
central star cluster is at or very close to the dynamical center, with a
velocity that is in accordance with M33's systemic velocity to within our
uncertainties. Velocities on the minor axis are non-zero out to about 1' from
the center in both the stars and gas. Together with the major axis velocities,
they point at significant deviations from circular rotation. The most likely
explanation for the bulk of the velocity patterns are streaming motions along a
weak inner bar with a PA close to that of the minor axis, as suggested by
previously published IR photometric images. The presence of bar imprints in M33
implies that all major Local Group galaxies are barred. The non-circular
motions over the inner 200 pc make it difficult to constrain the shape of M33's
inner dark matter halo profile. If the non-circular motions we find in this
nearby Sc galaxy are present in other more distant late-type galaxies, they
might be difficult to recognize.Comment: 20 pages, 12 figures, ApJ in pres
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