115,155 research outputs found
The Impact of a Regulatory Intervention on Resident-Centered Nursing Home Care: Rhode Island's Individualized Care Pilot
Evaluates a pilot project to promote resident-centered care through activities integrated with recertification inspections, including visits from a nonregulatory entity, and its impact on understanding, consideration, and implementation of practices
Kepler-10 c: a 2.2 Earth Radius Transiting Planet in a Multiple System
The Kepler mission has recently announced the discovery of Kepler-10 b, the smallest exoplanet discovered to date and the first rocky planet found by the spacecraft. A second, 45 day period transit-like signal present in the photometry from the first eight months of data could not be confirmed as being caused by a planet at the time of that announcement. Here we apply the light curve modeling technique known as BLENDER to explore the possibility that the signal might be due to an astrophysical false positive (blend). To aid in this analysis we report the observation of two transits with the Spitzer Space Telescope at 4.5 μm. When combined, they yield a transit depth of 344 ± 85 ppm that is consistent with the depth in the Kepler passband (376 ± 9 ppm, ignoring limb darkening), which rules out blends with an eclipsing binary of a significantly different color than the target. Using these observations along with other constraints from high-resolution imaging and spectroscopy, we are able to exclude the vast majority of possible false positives. We assess the likelihood of the remaining blends, and arrive conservatively at a false alarm rate of 1.6 × 10^(–5) that is small enough to validate the candidate as a planet (designated Kepler-10 c) with a very high level of confidence. The radius of this object is measured to be R_p = 2.227^(+0.052)_(–0.057) R_⊕ (in which the error includes the uncertainty in the stellar properties), but currently available radial-velocity measurements only place an upper limit on its mass of about 20 M_⊕. Kepler-10 c represents another example (with Kepler-9 d and Kepler-11 g) of statistical "validation" of a transiting exoplanet, as opposed to the usual "confirmation" that can take place when the Doppler signal is detected or transit timing variations are measured. It is anticipated that many of Kepler's smaller candidates will receive a similar treatment since dynamical confirmation may be difficult or impractical with the sensitivity of current instrumentation
A Comprehensive Evaluation Model for Cumputer Based Educaton
As opportunities to use computers in learning laboratory settings increase,directors will be faced with the problem of assisting faculty to select and evaluate themost appropriate courseware for their needs. This article presents a comprehensiveevaluation model that could be applied for computer based education programs in avariety of arts and sciences areas. The model includes a pre-implementation stage.This stage determines program compatibility, content evaluation and hardwareconsiderations. A second stage considers formative evaluation, continued availabilityof equipment and the recording of time records. Finally, the last phase, summativeevaluation, includes collecting student attitudes, assessing cost effectiveness,determining external influences and finally, suggesting ways of reaching a decision ofworth. The implementation of this model should provide a system where studentscould work with computer programs of a proven quality. Also, learning laboratorydirectors and faculty could show a certain level of accountability towards spendingmoney on computer software or courseware
The Ages of Stars
The age of an individual star cannot be measured, only estimated through
mostly model-dependent or empirical methods, and no single method works well
for a broad range of stellar types or for a full range in age. This review
presents a summary of the available techniques for age-dating stars and
ensembles of stars, their realms of applicability, and their strengths and
weaknesses. My emphasis is on low-mass stars because they are present from all
epochs of star formation in the Galaxy and because they present both special
opportunities and problems. The ages of open clusters are important for
understanding the limitations of stellar models and for calibrating empirical
age indicators. For individual stars, a hierarchy of quality for the available
age-dating methods is described. Although our present ability to determine the
ages of even the nearest stars is mediocre, the next few years hold great
promise as asteroseismology probes beyond stellar surfaces and starts to
provide precise interior properties of stars and as models continue to improve
when stressed by better observations.Comment: To appear in the 2010 volume of Annual Reviews of Astronomy and
Astrophysics
High fat diet causes rebound weight gain
Acknowledgements This work was funded by a grant from Action Medical Research (SP4581). We are grateful to the animal house staff for looking after the animals.Peer reviewedPublisher PD
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