3,508 research outputs found
A framework to combine low- and high-resolution spectroscopy for the atmospheres of transiting exoplanets
Current observations of the atmospheres of close-in exoplanets are
predominantly obtained with two techniques: low-resolution spectroscopy with
space telescopes and high-resolution spectroscopy from the ground. Although the
observables delivered by the two methods are in principle highly complementary,
no attempt has ever been made to combine them, perhaps due to the different
modeling approaches that are typically used in their interpretation. Here we
present the first combined analysis of previously-published dayside spectra of
the exoplanet HD 209458b obtained at low resolution with HST/WFC3 and
Spitzer/IRAC, and at high resolution with VLT/CRIRES. By utilizing a novel
retrieval algorithm capable of computing the joint probability distribution of
low- and high-resolution spectra, we obtain tight constraints on the chemical
composition of the planet's atmosphere. In contrast to the WFC3 data, we do not
confidently detect H2O at high spectral resolution. The retrieved water
abundance from the combined analysis deviates by 1.9 sigma from the
expectations for a solar-composition atmosphere in chemical equilibrium.
Measured relative molecular abundances of CO and H2O strongly favor an
oxygen-rich atmosphere (C/O<1 at 3.5 sigma) for the planet when compared to
equilibrium calculations including O rainout. From the abundances of the seven
molecular species included in this study we constrain the planet metallicity to
0.1-1.0x the stellar value (1 sigma). This study opens the way to coordinated
exoplanet surveys between the flagship ground- and space-based facilities,
which ultimately will be crucial for characterizing potentially-habitable
planets.Comment: 7 pages, 5 figures, accepted for publication in ApJL. Section 4
largely updated from previous version, Figure 2 updated to contain
information on the T-p profil
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Schwannomatosis of the Spinal Accessory Nerve: A Case Report.
Schwannomatosis is a distinct syndrome characterized by multiple peripheral nerve schwannomas that can be sporadic or familial in nature. Cases affecting the lower cranial nerves are infrequent. Here, the authors present a rare case of schwannomatosis affecting the left spinal accessory nerve. Upon genetic screening, an in-frame insertion at codon p.R177 of the Sox 10 gene was observed. There were no identifiable alterations in NF1, NF2, LZTR1, and SMARCB1. This case demonstrates a rare clinical presentation of schwannomatosis in addition to a genetic aberration that has not been previously reported in this disease context
Hyponatremia in Endurance Athletes
The purpose of this paper was to identify the relationship between hyponatremia, or water intoxication, and endurance athletes. Athletic trainers and paramedics must be educated about this potentially fatal problem and be able to determine the appropriate treatment for a hyponatremic athlete
Detecting Distracted Driving with Deep Learning
© Springer International Publishing AG 2017Driver distraction is the leading factor in most car crashes and near-crashes. This paper discusses the types, causes and impacts of distracted driving. A deep learning approach is then presented for the detection of such driving behaviors using images of the driver, where an enhancement has been made to a standard convolutional neural network (CNN). Experimental results on Kaggle challenge dataset have confirmed the capability of a convolutional neural network (CNN) in this complicated computer vision task and illustrated the contribution of the CNN enhancement to a better pattern recognition accuracy.Peer reviewe
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