536 research outputs found
Third molar removal and orofacial pain : a population-based survey
Peer reviewedPublisher PD
Strong resemblance between surface and deep zonal winds inside Jupiter revealed by high-degree gravity moments
Jupiter's atmosphere-interior is a coupled fluid dynamical system strongly
influenced by the rapid background rotation. While the visible atmosphere
features east-west zonal winds on the order of 100 m/s (Tollefson et al. 2017),
zonal flows in the dynamo region are significantly slower, on the order of 1
cm/s or less, according to the latest magnetic secular variation analysis
(Bloxham et al. 2022). The vertical profile of the zonal flows and the
underlying mechanism remain elusive. The latest Juno radio tracking
measurements afforded the derivation of Jupiter's gravity field to spherical
harmonic degree 40. Here, we use the latest gravity solution to reconstruct
Jupiter's deep zonal winds without a priori assumptions about their latitudinal
profile. The pattern of our reconstructed deep zonal winds strongly resembles
that of the surface wind within 35 degrees latitude from the equator, in
particular the northern off-equatorial jet (NOEJ) and the southern
off-equatorial jet (SOEJ) (Kulowski et al. 2021). The reconstruction features
larger uncertainties in the southern hemisphere due to the north south
asymmetric nature of Juno's trajectory. Amplitude of the reconstructed deep
NOEJ matches that of the surface wind when the wind is truncated at a depth
around 2500 km, and becomes twice that of the surface wind if the truncation
depth is reduced to about 1500 km. Our analysis supports the physical picture
in which prominent part of the surface zonal winds extends into Jupiter's
interior significantly deeper than the water cloud layer.Comment: Accepted for publication in ApJ, 11 pages, 6 figure
Detection of Helium in the Atmosphere of the Exo-Neptune HAT-P-11b
The helium absorption triplet at a wavelength of 10,833 \AA\ has been
proposed as a way to probe the escaping atmospheres of exoplanets. Recently
this feature was detected for the first time using Hubble Space Telescope (HST)
WFC3 observations of the hot Jupiter WASP-107b. We use similar HST/WFC3
observations to detect helium in the atmosphere of the hot Neptune HAT-P-11b at
the confidence level. We compare our observations to a grid of 1D
models of hydrodynamic escape to constrain the thermospheric temperatures and
mass loss rate. We find that our data are best fit by models with high mass
loss rates of - g s. Although we do
not detect the planetary wind directly, our data are consistent with the
prediction that HAT-P-11b is experiencing hydrodynamic atmospheric escape.
Nevertheless, the mass loss rate is low enough that the planet has only lost up
to a few percent of its mass over its history, leaving its bulk composition
largely unaffected. This matches the expectation from population statistics,
which indicate that close-in planets with radii greater than 2 R
form and retain H/He-dominated atmospheres. We also confirm the independent
detection of helium in HAT-P-11b obtained with the CARMENES instrument, making
this the first exoplanet with the detection of the same signature of
photoevaporation from both ground- and space-based facilities.Comment: 12 pages, 9 figures, accepted for publication in ApJ
A Precise Water Abundance Measurement for the Hot Jupiter WASP-43b
The water abundance in a planetary atmosphere provides a key constraint on
the planet's primordial origins because water ice is expected to play an
important role in the core accretion model of planet formation. However, the
water content of the Solar System giant planets is not well known because water
is sequestered in clouds deep in their atmospheres. By contrast, short-period
exoplanets have such high temperatures that their atmospheres have water in the
gas phase, making it possible to measure the water abundance for these objects.
We present a precise determination of the water abundance in the atmosphere of
the 2 short-period exoplanet WASP-43b based on thermal
emission and transmission spectroscopy measurements obtained with the Hubble
Space Telescope. We find the water content is consistent with the value
expected in a solar composition gas at planetary temperatures (0.4-3.5x solar
at 1 confidence). The metallicity of WASP-43b's atmosphere suggested
by this result extends the trend observed in the Solar System of lower metal
enrichment for higher planet masses.Comment: Accepted to ApJL; this version contains three supplemental figures
that are not included in the published paper. See also our companion paper
"Thermal structure of an exoplanet atmosphere from phase-resolved emission
spectroscopy" by Stevenson et a
Using Complex, Multi-Sectoral Data in a Needs Assessment to Inform Future Strategies in Childhood Asthma Management
The purpose of this needs assessment was to study the current state of asthma management in high-risk children in Houston, Texas to inform a theory-based approach to improving asthma management. The mixed-method assessment included multi-sectoral survey, quantitative, and geospatial data that address a range of social and community factors in family, community, home, and medical contexts. Houston Emergency Medical Services (EMS) provided ambulance-treated asthma data mapped by geographic area to identify where childhood asthma management was weakest. Texas Children’s Health Plan (TCHP) provided medication compliance rates and counts of children by zip code that TCHP considered high-risk according to claims data. Houston Independent School District (HISD) provided school nurse survey results from schools with high-rates of ambulance-treated asthma attacks regarding local barriers to asthma management. Elementary schools with children at highest risk were identified by overlaying the EMS data, TCHP data, and HISD school zone boundaries. Survey results from the high-rate schools indicate the priority challenges to childhood asthma management, including lack of resources, lack of communication, lack of knowledge of triggers, and inadequate time for quality care from providers. By weaving together EMS, TCHP, and HISD data, the needs assessment informed a socio-ecological view of gaps in high-risk childhood asthma management and control, specifically where and what to target. An assessment approach with multi-sectoral data, geospatial mapping, nurse input, current systems of care, education, and funding helped focus planning on a practical approach to asthma control solutions for high-risk children
Climate of an Ultra hot Jupiter: Spectroscopic phase curve of WASP-18b with HST/WFC3
We present the analysis of a full-orbit, spectroscopic phase curve of the
ultra hot Jupiter WASP-18b, obtained with the Wide Field Camera 3 aboard the
Hubble Space Telescope. We measure the planet's normalized day-night contrast
as >0.96 in luminosity: the disk-integrated dayside emission from the planet is
at 964+-25 ppm, corresponding to 2894+-30 K, and we place an upper limit on the
nightside emission of <32ppm or 1430K at the 3-sigma level. We also find that
the peak of the phase curve exhibits a small, but significant offset in
brightness of 4.5+-0.5 degrees eastward.
We compare the extracted phase curve and phase resolved spectra to 3D Global
Circulation Models and find that broadly the data can be well reproduced by
some of these models. We find from this comparison several constraints on the
atmospheric properties of the planet. Firstly we find that we need efficient
drag to explain the very inefficient day-night re-circulation observed. We
demonstrate that this drag could be due to Lorentz-force drag by a magnetic
field as weak as 10 Gauss. Secondly, we show that a high metallicity is not
required to match the large day-night temperature contrast. In fact, the effect
of metallicity on the phase curve is different from cooler gas-giant
counterparts, due to the high-temperature chemistry in WASP-18b's atmosphere.
Additionally, we compare the current UHJ spectroscopic phase curves, WASP-18b
and WASP-103b, and show that these two planets provide a consistent picture
with remarkable similarities in their measured and inferred properties.
However, key differences in these properties, such as their brightness offsets
and radius anomalies, suggest that UHJ could be used to separate between
competing theories for the inflation of gas-giant planets.Comment: Accepted for publication in A&
A HST/WFC3 Thermal Emission Spectrum of the Hot Jupiter HAT-P-7b
Secondary eclipse observations of several of the hottest hot Jupiters show
featureless, blackbody-like spectra or molecular emission features, which are
consistent with thermal inversions being present in those atmospheres. Theory
predicts a transition between warmer atmospheres with thermal inversions and
cooler atmospheres without inversions, but the exact transition point is
unknown. In order to further investigate this issue, we observed two secondary
eclipses of the hot Jupiter HAT-P-7b with the Hubble Space Telescope (HST) WFC3
instrument and combined these data with previous Spitzer and Kepler secondary
eclipse observations. The HST and Spitzer data can be well fit by a blackbody
with K, and the Kepler data point constrains the geometric
albedo to . We modeled these data with a 3D GCM and 1D
self-consistent forward models. The 1D models indicate that the atmosphere has
a thermal inversion, weak heat redistribution, and water dissociation that
limits the range of pressures probed. This result suggests that WFC3
observations of HAT-P-7b and possibly some other ultra-hot Jupiters appear
blackbody-like because they probe a region near the tropopause where the
atmospheric temperature changes slowly with pressure. Additionally, the 1D
models constrain the atmospheric metallicity
() and the carbon-to-oxygen ratio (C/O
at 99 % confidence). The solar composition 3D GCM matches the Spitzer data but
generally underpredicts the flux in the WFC3 bandpass and cannot reproduce its
featureless shape. This discrepancy could be explained by high atmospheric drag
or nightside clouds, and may be better understood through further observation
with the James Webb Space Telescope (JWST).Comment: 14 pages, 10 figures, submitted to AAS Journal
Does attendance at a specialist antenatal clinic improve clinical outcomes in women with Class III obesity compared to standard care? a retrospective case-note analysis
OBJECTIVES: To determine whether attendance at a specialised multidisciplinary antenatal clinic for women with class III obesity (BMI >40 kg/m2) is associated with improved clinical outcomes compared with standard antenatal care. DESIGN: Retrospective cohort study using routinely collected data from electronic patient record. SETTING: Community and hospital based antenatal care. PARTICIPANTS: Women with a singleton pregnancy with class III obesity booked for antenatal care and delivered in one of two hospitals in NHS Lothian, Scotland, UK between 2008 and 2014. Maternal and offspring outcomes were compared in women who attended a specialised obesity clinic (n=511) compared with standard antenatal care (n=502). MAIN OUTCOME MEASURES: Included stillbirth, low birth weight, gestational diabetes, induction of labour and caesarean section. RESULTS: Compared with standard care, women receiving specialist care were less likely to have a stillbirth (OR 0.12, 95% CI 0.06 to 0.97) and a low birthweight baby (OR 0.57, 95% CI 0.33 to 0.99) and more likely to be screened for (100% vs 73.6%; p<0.001) and diagnosed with (26.0% vs 12.5%; p<0.001) gestational diabetes, to require induction of labour (38.4% vs 29.9%; p=0.009), an elective (20.3% vs 17.7%; p<0.001) and emergency (23.9% vs 20.3%; p<0.001) caesarean section and attend antenatal triage one or more times during pregnancy (77.7% vs 53.1%; p<0.001). Women attending the specialist clinic had a higher BMI (44.5 kg/m2 (4.3) vs 43.2 kg/m2 (3.1); p<0.001) and were more likely to be nulliparous (46.0% vs 24.9%; p<0.001). There were no other differences in maternal demographic or maternal and offspring outcomes between groups. CONCLUSIONS: Attendance at a specialised antenatal clinic for obesity is associated with reduced rates of stillbirth and low birth weight and improved detection of gestational diabetes. The improvement in clinical outcomes is associated with an increase in healthcare attendance to obstetric triage and clinical interventions including induction of labour and caesarean section
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