1,034 research outputs found
A spectral survey of an ultra-hot Jupiter: Detection of metals in the transmission spectrum of KELT-9 b
Context: KELT-9 b exemplifies a newly emerging class of short-period gaseous
exoplanets that tend to orbit hot, early type stars - termed ultra-hot
Jupiters. The severe stellar irradiation heats their atmospheres to
temperatures of K, similar to the photospheres of dwarf stars. Due
to the absence of aerosols and complex molecular chemistry at such
temperatures, these planets offer the potential of detailed chemical
characterisation through transit and day-side spectroscopy. Studies of their
chemical inventories may provide crucial constraints on their formation process
and evolution history.
Aims: To search the optical transmission spectrum of KELT-9 b for absorption
lines by metals using the cross-correlation technique.
Methods: We analyse 2 transits observed with the HARPS-N spectrograph. We use
an isothermal equilibrium chemistry model to predict the transmission spectrum
for each of the neutral and singly-ionized atoms with atomic numbers between 3
and 78. Of these, we identify the elements that are expected to have spectral
lines in the visible wavelength range and use those as cross-correlation
templates.
Results: We detect absorption of Na I, Cr II, Sc II and Y II, and confirm
previous detections of Mg I, Fe I, Fe II and Ti II. In addition, we find
evidence of Ca I, Cr I, Co I, and Sr II that will require further observations
to verify. The detected absorption lines are significantly deeper than model
predictions, suggesting that material is transported to higher altitudes where
the density is enhanced compared to a hydrostatic profile. There appears to be
no significant blue-shift of the absorption spectrum due to a net day-to-night
side wind. In particular, the strong Fe II feature is shifted by km~s, consistent with zero. Using the orbital velocity of the
planet we revise the steller and planetary masses and radii.Comment: Submitted to Astronomy and Astrophysics on January 18, 2019. Accepted
on May 3, 2019. 26 pages, 11 figure
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Lake surface temperature [in âState of the Climate in 2017â]
Observed lake surface water temperature anomalies
in 2017 are placed in the context of the recent
warming observed in global surface air temperature
by collating long-term in situ lake
surface temperature observations from some of the
worldâs best-studied lakes and a satellite-derived
global lake surface water temperature dataset. The
period 1996â2015, 20 years for which satellite-derived
lake temperatures are available, is used as the base
period for all lake temperature anomaly calculations
\u27A constant black cloud\u27: The emotional impact of informal caregiving for someone with a lower-grade glioma
The effectiveness and satisfaction of web-based physiotherapy in people with spinal cord injury: a pilot randomised controlled trial
Study Design: Pilot randomised controlled trial.
Objectives: The aims of this study were to evaluate the effectiveness and participant satisfaction of web-based physiotherapy for people with Spinal Cord Injury (SCI).
Setting: Community patients of a national spinal injury unit in a university teaching hospital, Scotland, UK.
Methods: Twenty-four participants were recruited and randomised to receive eight weeks of web-based physiotherapy (intervention), twice per week, or usual care (control). Individual exercise programmes were prescribed based upon participantâs abilities. The intervention was delivered via a website (www.webbasedphysio.com) and monitored and progressed remotely by the physiotherapist.
Results: Participants logged on to the website an average of 1.4±0.8 times per week. Between-group differences, although not significant were more pronounced for the 6 minute walk test. Participants were positive about using web-based physiotherapy and stated they would be happy to use it again and would recommend it to others. Overall it was rated as either good or excellent.
Conclusions: Web-based physiotherapy was feasible and acceptable for people with SCI. Participants achieved good compliance with the intervention, rated the programme highly and beneficial for health and well-being at various states post injury. The results of this study warrant further work with a more homogenous sample
Linear stability in billiards with potential
A general formula for the linearized Poincar\'e map of a billiard with a
potential is derived. The stability of periodic orbits is given by the trace of
a product of matrices describing the piecewise free motion between reflections
and the contributions from the reflections alone. For the case without
potential this gives well known formulas. Four billiards with potentials for
which the free motion is integrable are treated as examples: The linear
gravitational potential, the constant magnetic field, the harmonic potential,
and a billiard in a rotating frame of reference, imitating the restricted three
body problem. The linear stability of periodic orbits with period one and two
is analyzed with the help of stability diagrams, showing the essential
parameter dependence of the residue of the periodic orbits for these examples.Comment: 22 pages, LaTex, 4 Figure
âIt changes everythingâ: Understanding how people experience the impact of living with a lower-grade glioma
Understanding supported self-management for people living with a lower-grade glioma: Implementation considerations through the lens of normalisation process theory
About ergodicity in the family of limacon billiards
By continuation from the hyperbolic limit of the cardioid billiard we show
that there is an abundance of bifurcations in the family of limacon billiards.
The statistics of these bifurcation shows that the size of the stable intervals
decreases with approximately the same rate as their number increases with the
period. In particular, we give numerical evidence that arbitrarily close to the
cardioid there are elliptic islands due to orbits created in saddle node
bifurcations. This shows explicitly that if in this one parameter family of
maps ergodicity occurs for more than one parameter the set of these parameter
values has a complicated structure.Comment: 17 pages, 9 figure
Characteristics and components of self-management interventions for improving quality of life in cancer survivors: a systematic review
Self-management can improve clinical and psychosocial outcomes in cancer survivors. Which intervention characteristics and components are beneficial is unclear, hindering implementation into practice. We systematically searched six databases from inception to 17 November 2021 for studies evaluating self-management interventions for adult cancer survivors post-treatment. Independent reviewers screened for eligibility. Data extraction included population and study characteristics, intervention characteristics (TIDieR) and components (PRISMS), (associations with) quality of life (QoL), self-efficacy, and economic outcomes. Study quality was appraised, and narrative synthesis was conducted. We identified 53 papers reporting 32 interventions. Studies had varying quality. They were most often randomised controlled trials (n = 20), targeted at survivors of breast (n = 10), prostate (n = 7), or mixed cancers (n = 11). Intervention characteristics (e.g., provider, location) varied considerably. On average, five (range 1â10) self-management components were delivered, mostly âInformation about condition and its managementâ (n = 26). Twenty-two studies reported significant QoL improvements (6 also reported significant self-efficacy improvements); these were associated most consistently with combined individual and group delivery. Economic evaluations were limited and inconclusive. Self-management interventions showed promise for improving QoL, but study quality was variable, with substantial heterogeneity in intervention characteristics and components. By identifying what to adapt from existing interventions, these findings can inform development and implementation of self-management interventions in cancer
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