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Smoking Cessation Interventions After Lung Cancer Screening Guideline Change
Introduction: Recent guideline changes for lung cancer screening with low-dose computed tomography recommend smoking cessation interventions be done in parallel with screening. The purpose of this study is to determine the post-guideline rates of smoking cessation interventions among patients eligible and ineligible for lung cancer screening.Methods: Using electronic health records collected from a large ambulatory care system in northern California between 2010 and 2017, authors identified new patients who were current smokers aged 55–80 years visiting a primary care provider, and grouped patients into lung cancer screening–eligible heavy smokers, screening-ineligible moderate smokers, and screening-ineligible light smokers. Screening-eligible smokers versus screening-ineligible smokers were compared in receipt of smoking cessation interventions before (2010–2013) and after (2014–2017) the guideline change, overall and by intervention type (formal counseling, informal counseling, pharmacotherapy) using hierarchical generalized linear models. Analyses were conducted in 2018–2019.Results: After the guideline change, the likelihood of receiving any smoking cessation intervention (OR=1.44, 95% CI=1.28, 1.61, p<0.05), informal counseling (OR=1.29, 95% CI=1.15, 1.46, p<0.05), and pharmacotherapy (OR=1.24, 95% CI=1.02, 1.50, p<0.05) during a new patient visit significantly increased, with the increase not varying by level of smoking. For formal counseling, the post-guideline increase was greater for screening-eligible heavy smokers (OR=3.15, 95% CI=1.18, 8.36, p<0.05) and moderate smokers (OR=3.58, 95% CI=1.29, 9.95, p<0.05) relative to light smokers.Conclusions: Smoking cessation interventions increased after new lung cancer screening guidelines. Given the sizable adverse impacts of smoking on morbidity and mortality, small increases in implementation of smoking cessation interventions could have substantial public health benefits
Disintegrating Asteroid P/2013 R3
Splitting of the nuclei of comets into multiple components has been
frequently observed but, to date, no main-belt asteroid has been observed to
break-up. Using the Hubble Space Telescope, we find that main-belt asteroid
P/2013 R3 consists of 10 or more distinct components, the largest up to 200 m
in radius (assumed geometric albedo of 0.05) each of which produces a coma and
comet-like dust tail. A diffuse debris cloud with total mass roughly 2x10^8 kg
further envelopes the entire system. The velocity dispersion among the
components is about V = 0.2 to 0.5 m/s, is comparable to the gravitational
escape speeds of the largest members, while their extrapolated plane-of-sky
motions suggest break-up between February and September 2013. The broadband
optical colors are those of a C-type asteroid. We find no spectral evidence for
gaseous emission, placing model-dependent upper limits to the water production
rate near 1 kg/s. Breakup may be due to a rotationally induced structural
failure of the precursor body.Comment: 16 pages, 3 figures; accepted by ApJ
Nucleus and Mass Loss from Active Asteroid 313P/Gibbs
We present Hubble Space Telescope observations of active asteroid 313P/Gibbs
(formerly P/2014 S4) taken over the five month interval from 2014 October to
2015 March. This object has been recurrently active near perihelion (at 2.4 AU)
in two different orbits, a property that is naturally explained by the
sublimation of near surface ice but which is difficult to reconcile with other
activity mechanisms. We find that the mass loss peaks near 1 kg s in
October and then declines over the subsequent months by about a factor of five,
at nearly constant heliocentric distance. This decrease is too large to be
caused by the change in heliocentric distance during the period of observation.
However, it is consistent with sublimation from an ice patch shadowed by local
topography, for example in a pit like those observed on the nuclei of
short-period comet 67P/Churyumov-Gerasimenko. While no unique interpretation is
possible, a simple self shadowing model shows that sublimation from a pit with
depth to diameter ratio near 1/2 matches the observed rate of decline of the
activity, while deeper and shallower pits do not. We estimate the nucleus
radius to be 700100 m (geometric albedo 0.05 assumed). Measurements of the
spatial distribution of the dust were obtained from different viewing
geometries. They show that dust was ejected continuously not impulsively, that
the effective particle size is large, 50 , and that the ejection
speed is 2.5 m s. The total dust mass ejected is 10 kg,
corresponding to 10 of the nucleus mass. The observations are
consistent with partially shadowed sublimation from 10 m of ice,
corresponding to 0.2\% of the nucleus surface. For ice to survive in 313P
for billion-year timescales requires that the duty cycle for sublimation be
10.Comment: 34 pages, 11 figures, 4 tables; Astronomical Journal: in pres
The Nucleus of Active Asteroid 311P/(2013 P5) PANSTARRS
The unique inner-belt asteroid 311P/PANSTARRS (formerly P/2013 P5) is notable
for its sporadic, comet-like ejection of dust in nine distinct epochs spread
over 250 days in 2013. This curious behavior has been interpreted as the
product of localized, equator-ward landsliding from the surface of an asteroid
rotating at the brink of instability. We obtained new Hubble Space Telescope
observations to directly measure the nucleus and to search for evidence of its
rapid rotation. However, instead of providing photometric evidence for rapid
nucleus rotation, our data set a lower limit to the lightcurve period,
5.4 hour. The dominant feature of the lightcurve is a V-shaped minimum,
0.3 magnitudes deep, that is suggestive of an eclipsing binary. Under
this interpretation, the time-series data are consistent with a
secondary/primary mass ratio, 1:6, a ratio of separation/primary
radius, 4 and an orbit period 0.8 days. These properties lie
within the range of other asteroid binaries that are thought to be formed by
rotational breakup. While the lightcurve period is long, centripetal dust
ejection is still possible if one or both components rotates rapidly
( 2 hour) and has a small lightcurve variation because of azimuthal
symmetry. Indeed, radar observations of asteroids in critical rotation reveal
"muffin-shaped" morphologies which are closely azimuthally symmetric and which
show minimal lightcurves. Our data are consistent with 311P being a close
binary in which one or both components rotates near the centripetal limit. The
mass loss in 2013 suggests that breakup occurred recently and could even be
on-going. A search for fragments that might have been recently ejected beyond
the Hill sphere reveals none larger than effective radius 10 m.Comment: 37 pages, 9 figures, Astronomical Journal, in pres
Anatomy of an Asteroid Break-Up: The Case of P/2013 R3
We present an analysis of new and published data on P/2013 R3, the first
asteroid detected while disintegrating. Thirteen discrete components are
measured in the interval between UT 2013 October 01 and 2014 February 13. We
determine a mean, pair-wise velocity dispersion amongst these components of
m s and find that their separation times are
staggered over an interval of 5 months. Dust enveloping the system has,
in the first observations, a cross-section 30 km but fades
monotonically at a rate consistent with the action of radiation pressure
sweeping. The individual components exhibit comet-like morphologies and also
fade except where secondary fragmentation is accompanied by the release of
additional dust. We find only upper limits to the radii of any embedded solid
nuclei, typically 100 to 200 m (geometric albedo 0.05 assumed). Combined,
the components of P/2013 R3 would form a single spherical body with radius
400 m, which is our best estimate of the size of the precursor
object. The observations are consistent with rotational disruption of a weak
(cohesive strength 50 to 100 N m) parent body, 400 m in
radius. Estimated radiation (YORP) spin-up times of this parent are 1
Myr, shorter than the collisional lifetime. If present, water ice sublimating
at as little as 10 kg s could generate a torque on the parent
body rivaling the YORP torque. Under conservative assumptions about the
frequency of similar disruptions, the inferred asteroid debris production rate
is 10 kg s, which is at least 4% of the rate needed to
maintain the Zodiacal Cloud.Comment: 44 pages, 13 figures, accepted by Astronomical Journa
A Comet Active Beyond the Crystallization Zone
We present observations showing in-bound long-period comet C/2017 K2
(PANSTARRS) to be active at record heliocentric distance. Nucleus temperatures
are too low (60 K to 70 K) either for water ice to sublimate or for amorphous
ice to crystallize, requiring another source for the observed activity. Using
the Hubble Space Telescope we find a sharply-bounded, circularly symmetric dust
coma 10 km in radius, with a total scattering cross section of 10
km. The coma has a logarithmic surface brightness gradient -1 over much of
its surface, indicating sustained, steady-state dust production. A lack of
clear evidence for the action of solar radiation pressure suggests that the
dust particles are large, with a mean size 0.1 mm. Using a coma
convolution model, we find a limit to the apparent magnitude of the nucleus 25.2 (absolute magnitude 12.9). With assumed geometric albedo =
0.04, the limit to the nucleus circular equivalent radius is 9 km.
Pre-discovery observations from 2013 show that the comet was also active at
23.7 AU heliocentric distance. While neither water ice sublimation nor
exothermic crystallization can account for the observed distant activity, the
measured properties are consistent with activity driven by sublimating
supervolatile ices such as CO, CO, O and N. Survival of
supervolatiles at the nucleus surface is likely a result of the comet's recent
arrival from the frigid Oort cloud.Comment: 20 pages, 3 figures, 2 tables, published on Astrophysical Journal
Letters, 847:L19 (5pp), 2017 October
Detecting Photon-Photon Interactions in a Superconducting Circuit
A local interaction between photons can be engineered by coupling a nonlinear
system to a transmission line. The required high impedance transmission line
can be conveniently formed from a chain of Josephson junctions. The
nonlinearity is generated by side-coupling this chain to a Cooper pair box. We
propose to probe the resulting photon-photon interactions via their effect on
the current-voltage characteristic of a voltage-biased Josephson junction
connected to the transmission line. Considering the Cooper pair box to be in
the weakly anharmonic regime, we find that the dc current through the probe
junction yields features around the voltages , where
is the plasma frequency of the superconducting circuit. The features
at are a direct signature of the photon-photon interaction in the
system.Comment: 10 pages, 7 figure
Domain Conditioned Adaptation Network
Tremendous research efforts have been made to thrive deep domain adaptation
(DA) by seeking domain-invariant features. Most existing deep DA models only
focus on aligning feature representations of task-specific layers across
domains while integrating a totally shared convolutional architecture for
source and target. However, we argue that such strongly-shared convolutional
layers might be harmful for domain-specific feature learning when source and
target data distribution differs to a large extent. In this paper, we relax a
shared-convnets assumption made by previous DA methods and propose a Domain
Conditioned Adaptation Network (DCAN), which aims to excite distinct
convolutional channels with a domain conditioned channel attention mechanism.
As a result, the critical low-level domain-dependent knowledge could be
explored appropriately. As far as we know, this is the first work to explore
the domain-wise convolutional channel activation for deep DA networks.
Moreover, to effectively align high-level feature distributions across two
domains, we further deploy domain conditioned feature correction blocks after
task-specific layers, which will explicitly correct the domain discrepancy.
Extensive experiments on three cross-domain benchmarks demonstrate the proposed
approach outperforms existing methods by a large margin, especially on very
tough cross-domain learning tasks.Comment: Accepted by AAAI 202
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