21 research outputs found
Interim analyses from a randomised controlled trial to improve visual processing speed in older adults: the Iowa Healthy and Active Minds Study
Planetary Candidates Observed by Kepler. VIII. A Fully Automated Catalog With Measured Completeness and Reliability Based on Data Release 25
We present the Kepler Object of Interest (KOI) catalog of transiting
exoplanets based on searching four years of Kepler time series photometry (Data
Release 25, Q1-Q17). The catalog contains 8054 KOIs of which 4034 are planet
candidates with periods between 0.25 and 632 days. Of these candidates, 219 are
new and include two in multi-planet systems (KOI-82.06 and KOI-2926.05), and
ten high-reliability, terrestrial-size, habitable zone candidates. This catalog
was created using a tool called the Robovetter which automatically vets the
DR25 Threshold Crossing Events (TCEs, Twicken et al. 2016). The Robovetter also
vetted simulated data sets and measured how well it was able to separate TCEs
caused by noise from those caused by low signal-to-noise transits. We discusses
the Robovetter and the metrics it uses to sort TCEs. For orbital periods less
than 100 days the Robovetter completeness (the fraction of simulated transits
that are determined to be planet candidates) across all observed stars is
greater than 85%. For the same period range, the catalog reliability (the
fraction of candidates that are not due to instrumental or stellar noise) is
greater than 98%. However, for low signal-to-noise candidates between 200 and
500 days around FGK dwarf stars, the Robovetter is 76.7% complete and the
catalog is 50.5% reliable. The KOI catalog, the transit fits and all of the
simulated data used to characterize this catalog are available at the NASA
Exoplanet Archive.Comment: 61 pages, 23 Figures, 9 Tables, Accepted to The Astrophysical Journal
Supplement Serie
The Occurrence of Rocky Habitable-zone Planets around Solar-like Stars from Kepler Data
We present the occurrence rates for rocky planets in the habitable zones (HZs) of main-sequence dwarf stars based on the Kepler DR25 planet candidate catalog and Gaia-based stellar properties. We provide the first analysis in terms of star-dependent instellation flux, which allows us to track HZ planets. We define Ī·ā as the HZ occurrence of planets with radii between 0.5 and 1.5 Rā orbiting stars with effective temperatures between 4800 and 6300 K. We find that Ī·ā for the conservative HZ is between 0.37^(+0.48)_(ā0.21) (errors reflect 68% credible intervals) and 0.60^(+0.90)_(ā0.36) planets per star, while the optimistic HZ occurrence is between 0.58^(+0.73)_(ā0.33) and 0.88^(+1.28)_(ā0.51) planets per star. These bounds reflect two extreme assumptions about the extrapolation of completeness beyond orbital periods where DR25 completeness data are available. The large uncertainties are due to the small number of detected small HZ planets. We find similar occurrence rates between using Poisson likelihood Bayesian analysis and using Approximate Bayesian Computation. Our results are corrected for catalog completeness and reliability. Both completeness and the planet occurrence rate are dependent on stellar effective temperature. We also present occurrence rates for various stellar populations and planet size ranges. We estimate with 95% confidence that, on average, the nearest HZ planet around G and K dwarfs is ~6 pc away and there are ~4 HZ rocky planets around G and K dwarfs within 10 pc of the Sun
The Occurrence of Rocky Habitable Zone Planets Around Solar-Like Stars from Kepler Data
We present occurrence rates for rocky planets in the habitable zones (HZ) of
main-sequence dwarf stars based on the Kepler DR25 planet candidate catalog and
Gaia-based stellar properties. We provide the first analysis in terms of
star-dependent instellation flux, which allows us to track HZ planets. We
define as the HZ occurrence of planets with radius between 0.5
and 1.5 orbiting stars with effective temperatures between 4800 K
and 6300 K. We find that for the conservative HZ is between
(errors reflect 68\% credible intervals) and
planets per star, while the optimistic HZ occurrence is
between and planets per star.
These bounds reflect two extreme assumptions about the extrapolation of
completeness beyond orbital periods where DR25 completeness data are available.
The large uncertainties are due to the small number of detected small HZ
planets. We find similar occurrence rates using both a Poisson likelihood
Bayesian analysis and Approximate Bayesian Computation. Our results are
corrected for catalog completeness and reliability. Both completeness and the
planet occurrence rate are dependent on stellar effective temperature. We also
present occurrence rates for various stellar populations and planet size
ranges. We estimate with confidence that, on average, the nearest HZ
planet around G and K dwarfs is about 6 pc away, and there are about 4 HZ rocky
planets around G and K dwarfs within 10 pc of the Sun.Comment: To appear in The Astronomical Journa
Speed of processing training and depression in assisted and independent living: A randomized controlled trial.
Late life depression is widely associated with lower quality of life and greater disability, making it an important target for prevention. Earlier randomized controlled trials [RCTs] demonstrated that speed of processing training [SOPT] led to reductions in depressive symptoms and clinical depression in community-dwelling adults. Our purpose was to evaluate depression outcomes related to SOPT among older adults who live in supported senior living settings. This two-arm, parallel RCT included 351 participants aged 55-102 years who resided in assisted and independent settings in 31 senior living communities. Participants were randomized within sites to computerized SOPT vs. computerized crossword puzzles with a targeted dose of 10 hours of playtime at baseline plus 4 hours of booster training at five and eleven months. Depression outcomes included the 9-item Patient Health Questionnaire [PHQ-9] scores, categorical levels, and dichotomous indicators. Random effects linear mixed effect models estimated SOPT effects in intention-to-treat complete case and multiple imputation analyses. Mean age of the sample was 81.0 years, 72.2% were women, and 41.0% resided in assisted living. At baseline 65.7% had no depression [PHQ-9 scores 3 [p = 0.016] and major depressive syndrome [p = 0.045] among the assisted living SOPT group. No significant change in depression was observed in the independent living SOPT or attention control groups. In summary, the SOPT known as Road Tour/Double Decision significantly increased, rather than decreased, the burden of depressive symptoms among participants residing in assisted living. Given these risks, this SOPT program should be avoided among older people in assisted living settings, and other SOPT interventions should be combined with systematic depression monitoring
A randomized controlled trial of cognitive training using a visual speed of processing intervention in middle aged and older adults.
Age-related cognitive decline is common and may lead to substantial difficulties and disabilities in everyday life. We hypothesized that 10 hours of visual speed of processing training would prevent age-related declines and potentially improve cognitive processing speed.Within two age bands (50-64 and ā„ 65) 681 patients were randomized to (a) three computerized visual speed of processing training arms (10 hours on-site, 14 hours on-site, or 10 hours at-home) or (b) an on-site attention control group using computerized crossword puzzles for 10 hours. The primary outcome was the Useful Field of View (UFOV) test, and the secondary outcomes were the Trail Making (Trails) A and B Tests, Symbol Digit Modalities Test (SDMT), Stroop Color and Word Tests, Controlled Oral Word Association Test (COWAT), and the Digit Vigilance Test (DVT), which were assessed at baseline and at one year. 620 participants (91%) completed the study and were included in the analyses. Linear mixed models were used with Blom rank transformations within age bands.All intervention groups had (p<0.05) small to medium standardized effect size improvements on UFOV (Cohen's d = -0.322 to -0.579, depending on intervention arm), Trails A (d = -0.204 to -0.265), Trails B (d = -0.225 to -0.320), SDMT (d = 0.263 to 0.351), and Stroop Word (d = 0.240 to 0.271). Converted to years of protection against age-related cognitive declines, these effects reflect 3.0 to 4.1 years on UFOV, 2.2 to 3.5 years on Trails A, 1.5 to 2.0 years on Trails B, 5.4 to 6.6 years on SDMT, and 2.3 to 2.7 years on Stroop Word.Visual speed of processing training delivered on-site or at-home to middle-aged or older adults using standard home computers resulted in stabilization or improvement in several cognitive function tests. Widespread implementation of this intervention is feasible.ClinicalTrials.gov NCT-01165463
How the Visual Speed of Processing Training Program Appears to the User.
<p>How the Visual Speed of Processing Training Program Appears to the User.</p
Baseline Group Means on Background Characteristics by Treatment Group within Age Bands, among Participants with Complete Data at Baseline and One Year.
*<p>VSPā=āvisual speed of processing.</p
Intent-to-Treat Linear Mixed Model Results for the Blom Rank Transformed Primary and Secondary Outcomes (the Comparator is always the Attention Control Group), Nā=ā620.
*<p>p<0.05; **p<0.01; ***p<0.001</p><p><u>Notes</u>: Cell entries are Cohen's <i>d</i> statistics (95% confidence intervals) for visual speed of processing training on the baseline to one-year changes between each training group vs. the attention control group on the Blom rank transformed (separately within age strata) scores, and are directly interpretable as standardized effect sizes. Cell p values are from Dunnett test comparisons to the attention control group. None of the age band main effects were statistically significant, and none of the interaction terms involving age band were statistically significant.</p