103 research outputs found
Structure in the Epislon Eridani dusty disk caused by mean motion resonances with a 0.3 eccentricity planet at periastron
The morphology of the epsilon Eridani dust ring is reproduced by a numerical
simulation of dust particles captured into the 5:3 and 3:2 exterior mean-motion
resonances with a 0.3 eccentricity 10^-4 solar mass planet at periastron at a
semi-major axis of 40 AU. The morphology will differ when the planet is at
aphelion, in about 140 years. Moderate eccentricity planets in outer
extra-solar systems will cause observable variations in the morphology of
associated dusty rings.Comment: accepted to ApJ
Lake Ontario Coastal Initiative Action Agenda
The mission of the Lake Ontario Coastal Initiative (LOCI), encompassing all New York State North Coast stakeholders from the Niagara River to the St. Lawrence River, is to enlist and retain broad public commitment for remediation, restoration, protection, conservation and sustainable use of the coastal region. This mission will be accomplished by securing funds and resources to achieve scientific understanding, educate citizens, and implement locally supported priorities, programs and projects as identified through this Initiative
Effect of Personalized Incentives on Dietary Quality of Groceries Purchased A Randomized Crossover Trial
Importance Many factors are associated with food choice. Personalized interventions could help improve dietary intake by using individual purchasing preferences to promote healthier grocery purchases.
Objective To test whether a healthy food incentive intervention using an algorithm incorporating customer preferences, purchase history, and baseline diet quality improves grocery purchase dietary quality and spending on healthy foods.
Design, Setting, and Participants This was a 9-month randomized clinical crossover trial (AB–BA) with a 2- to 4-week washout period between 3-month intervention periods. Participants included 224 loyalty program members at an independent Rhode Island supermarket who completed baseline questionnaires and were randomized from July to September 2018 to group 1 (AB) or group 2 (BA). Data analysis was performed from September 2019 to May 2020.
Intervention Participants received personalized weekly coupons with nutrition education during the intervention period (A) and occasional generic coupons with nutrition education during the control period (B). An automated study algorithm used customer data to allocate personalized healthy food incentives to participant loyalty cards. All participants received a 5% grocery discount.
Main Outcomes and Measures Grocery Purchase Quality Index–2016 (GPQI-16) scores (range, 0-75, with higher scores denoting healthier purchases) and percentage spending on targeted foods were calculated from cumulative purchasing data. Participants in the top and bottom 1% of spending were excluded. Paired t tests examined between-group differences.
Results The analytical sample included 209 participants (104 in group 1 and 105 in group 2), with a mean (SD) age of 55.4 (14.0) years. They were predominantly non-Hispanic White (193 of 206 participants [94.1%]) and female (187 of 207 participants [90.3%]). Of 161 participants with income data, 81 (50.3%) had annual household incomes greater than or equal to $100 000. Paired t tests showed that the intervention increased GPQI-16 scores (between-group difference, 1.06; 95% CI, 0.27-1.86; P = .01) and percentage spending on targeted foods (between-group difference, 1.38%; 95% CI, 0.08%-2.69%; P = .04). During the initial intervention period, group 1 (AB) and group 2 (BA) had similar mean (SD) GPQI-16 scores (41.2 [6.6] vs 41.0 [7.5]) and mean (SD) percentage spending on targeted healthy foods (32.0% [10.8%] vs 31.0% [10.5%]). During the crossover intervention period, group 2 had a higher mean (SD) GPQI-16 score than group 1 (42.9 [7.7] vs 41.0 [6.8]) and mean (SD) percentage spending on targeted foods (34.0% [12.1%] vs 32.0% [13.1%]).
Conclusions and Relevance This pilot trial demonstrated preliminary evidence for the effectiveness of a novel personalized healthy food incentive algorithm to improve grocery purchase dietary quality.
Trial Registration ClinicalTrials.gov Identifier: NCT0374805
Turbulence driven by outflow-blown cavities in the molecular cloud of NGC 1333
Outflows from young stellar objects have been identified as a possible source
of turbulence in molecular clouds. To investigate the relationship between
outflows, cloud dynamics and turbulence, we compare the kinematics of the
molecular gas associated with NGC 1333, traced in 13CO(1-0), with the
distribution of young stellar objects (YSOs) within. We find a velocity
dispersion of ~ 1-1.6 km/s in 13CO that does not significantly vary across the
cloud, and is uncorrelated with the number of nearby young stellar outflows
identified from optical and submillimeter observations. However, from velocity
channel maps we identify about 20 cavities or depressions in the 13CO intensity
of scales > 0.1-0.2 pc and velocity widths 1-3 km/s. The cavities exhibit limb
brightened rims in both individual velocity channel maps and position velocity
diagrams, suggesting that they are slowly expanding. We interpret these
cavities to be remnants of past YSO outflow activity: If these cavities are
presently empty, they would fill in on time scales of a million years. This can
exceed the lifetime of a YSO outflow phase, or the transit time of the central
star through the cavity, explaining the the absence of any clear correlation
between the cavities and YSO outflows. We find that the momentum and energy
deposition associated with the expansion of the cavities is sufficient to power
the turbulence in the cloud. In this way we conclude that the cavities are an
important intermediary step between the conversion of YSO outflow energy and
momentum into cloud turbulent motions.Comment: Accepted for publication in ApJ. Check out
http://astro.pas.rochester.edu/~aquillen/coolpics.html for channel map and
PosVel movies of N133
Recommended from our members
Nephelometer measurements, HACH turbidimeter measurements and bottom photopgraphs from CONRAD cruise 15
Model-Independent Global Constraints on New Physics
Using effective-lagrangian techniques we perform a systematic survey of the
lowest-dimension effective interactions through which heavy physics might
manifest itself in present experiments. We do not restrict ourselves to special
classes of effective interactions (such as `oblique' corrections). We compute
the effects of these operators on all currently well-measured electroweak
observables, both at low energies and at the resonance, and perform a
global fit to their coefficients. Despite the fact that a great many operators
arise in our survey, we find that most are quite strongly bounded by the
current data. We use our survey to systematically identify those effective
interactions which are {\it not} well-bounded by the data -- these could very
well include large new-physics contributions. Our results may also be used to
efficiently confront specific models for new physics with the data, as we
illustrate with an example.Comment: plain TeX, 68 pages, 2 figures (postscript files appended),
McGill-93/12, NEIPH-93-008, OCIP/C-93-6, UQAM-PHE-93/08, UdeM-LPN-TH-93-15
Etiological distinction of working memory components in relation to mathematics.
Working memory has been consistently associated with mathematics achievement, although the etiology of these relations remains poorly understood. The present study examined the genetic and environmental underpinnings of math story problem solving, timed calculation, and untimed calculation alongside working memory components in 12-year-old monozygotic (n = 105) and same-sex dizygotic (n = 143) twin pairs. Results indicated significant phenotypic correlation between each working memory component and all mathematics outcomes (r = 0.18 - 0.33). Additive genetic influences shared between the visuo-spatial sketchpad and mathematics achievement was significant, accounting for roughly 89% of the observed correlation. In addition, genetic covariance was found between the phonological loop and math story problem solving. In contrast, despite there being a significant observed relationship between phonological loop and timed and untimed calculation, there was no significant genetic or environmental covariance between the phonological loop and timed or untimed calculation skills. Further analyses indicated that genetic overlap between the visuo-spatial sketchpad and math story problem solving and math fluency was distinct from general genetic factors, whereas g, phonological loop, and mathematics shared generalist genes. Thus, although each working memory component was related to mathematics, the etiology of their relationships may be distinct
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