Mexican-heritage youth living along the U.S.-Mexico border have higher rates of obesity than non-Hispanic Whites. Parenting strategies may influence youth physical activity (PA) and sedentary ...behaviors (SB) mitigating these obesity rates; however, parenting strategies have not been well examined in Hispanic cultures. Therefore, we examined relationships between parenting strategies and PA and SB of Mexican-heritage youth. Motherchild dyads (n = 121 dyads) were surveyed during the summer and school-year. Quantile regression estimated relationships between parenting strategies, and PA and SB. Summer. Reinforcement was negatively associated with moderate-to-vigorous PA (MVPA) among more active youth (ß =-364.4); limit setting was negatively associated with SB among less sedentary youth (ß =-23.3); and use of discipline was negatively associated with sedentary screen time in youth reporting less screen use (ß =-3.2). School-year. Males reported more MVPA (773.9 min/week) than females (738.7 min/week). Reinforcement was positively associated with weekly MVPA among more active youth (β = 173.6), fewer sedentary minutes/week among all youth, and fewer sedentary screen time minutes among less sedentary youth β =-6.4). Parenting strategies are related with PA and SB. Investigators should focus on identifying modifiable parenting strategies to address the various needs presented during summertime and schoolyear for Mexican-heritage youth.
Ground based radial velocity (RV) searches continue to discover exoplanets below Neptune mass down to Earth mass. Furthermore, ground based transit searches now reach milli-mag photometric precision ...and can discover Neptune size planets around bright stars. These searches will find exoplanets around bright stars anywhere on the sky, their discoveries representing prime science targets for further study due to the proximity and brightness of their host stars. A mission for transit follow-up measurements of these prime targets is currently lacking. The first ESA S-class mission CHEOPS (CHaracterizing ExoPlanet Satellite) will fill this gap. It will perform ultra-high precision photometric monitoring of selected bright target stars almost anywhere on the sky with sufficient precision to detect Earth sized transits. It will be able to detect transits of RV-planets by photometric monitoring if the geometric configuration results in a transit. For Hot Neptunes discovered from the ground, CHEOPS will be able to improve the transit light curve so that the radius can be determined precisely. Because of the host stars' brightness, high precision RV measurements will be possible for all targets. All planets observed in transit by CHEOPS will be validated and their masses will be known. This will provide valuable data for constraining the mass-radius relation of exoplanets, especially in the Neptune-mass regime. During the planned 3.5 year mission, about 500 targets will be observed. There will be 20% of open time available for the community to develop new science programmes.
Toroidal atmospheres and exospheres characterized at exoplanets may be fueled by volcanically active exomoons, often referred to as exo‐Ios. We study the neutral outgassing and volatile evolution of ...a close‐orbiting, evaporating satellite at eight candidate exoplanet‐exomoon systems WASP‐49,‐96,‐69,‐17 b, XO‐2N b, HAT‐P‐1 b, HD‐189733 b, and HD‐209458 b by developing a 3‐D test‐particle Monte Carlo simulation, Simulating the Evolution of Ring Particles Emergent from Natural Satellites. The module is coupled to dishoom, approximating the minimum mass‐flux needed to reproduce observations of alkali line profiles identified in dozens of transmission spectra. We focus on sputtered neutral sodium, limited by photoionization and radiative effects. By considering Earth‐, Io‐, and Enceladus‐like masses, we systematically simulate the imprint of a non‐hydrostatic medium (characteristic of volcanic exospheres) in density and velocity space using a novel Delaunay tesselation field estimator algorithm. Our results demonstrate how exomoons can considerably modulate gas density observations probed near exoplanet transit, depending on the orbital phase of the putative satellite at the time of observation. The density evolution, therefore, manifests on orbital timescales as “exomoon phase curves” from shadow to occultation. We find two regimes of density evolution, characteristic of a: (a) localized cloud and (b) an azimuthally symmetric exoring/torus, degenerate with an exoplanet atmosphere, ranging from ∼109.5±0.5 cm−2 to ∼1015±0.25 cm−2 at our leading candidate WASP‐69b I. In certain orbital architectures, the smallest evaporating satellite mass surprisingly generates the brightest sodium signal, fueling optimism for discovering photometrically indiscernible rocky exomoons. We suggest long baseline monitoring of alkali and SO2 systems in spectroscopy to search for the temporal and spatial variability predicted here.
Plain Language Summary
Intense gravitational tidal forces from Jupiter on its rocky moon Io, drives rock melting and over a ∼ kiloton/second of sulfur dioxide and alkali metal volcanism. Io is therefore the most geologically active body in the Solar System, with infrared‐bright lavas despite its surface temperature of −130°C. The roughly lunar‐sized moon is bombarded by charged particle radiation that knocks off volcanic material, thereby fueling a conducting ring of plasma orbiting Jupiter every ∼10 hr along with extended clouds of sodium and potassium radiating across the electromagnetic spectrum. Motivated by dozens of observations of alkalis at exoplanets, we posit that some of these systems may host hidden extrasolar Ios. Exo‐Ios at 8 exoplanet systems are simulated with a novel code in 3‐D (SERPENS) treating Earth, Io, and Enceladus‐mass satellites. Our open‐source software tracks the evolution of orbiting neutral particles and simulates high‐velocity banana‐shaped clouds and extrasolar ring structures, consistent with data. We urge the astronomy community to search for exo‐Ios, and have provided exomoon phase curves, predicting the disappearance of metallic signatures due to the temporal and spatial variability modeled. Our results are surprisingly optimistic in that the smallest exomoon mass generates the brightest signal in certain scenarios, not unlike Saturn's E‐ring.
Key Points
A 3‐D MC code simulates the sputtering & outgassing of an exomoon at 8 candidate systems to provide density maps of the neutral environment
Exomoon phase‐curves that is, spatial & temporal variations of orbiting alkali clouds & tori imprinted in transmission spectra are predicted
Our open access module Simulating the Evolution of Ring Particles Emergent from Natural Satellites allows one to simulate the evaporation of an exomoon and its ability to form a volcanic exoring/exosphere
Interstellar Carbon in Translucent Sight Lines Sofia, Ulysses J; Lauroesch, James T; Meyer, David M ...
Astrophysical journal/The Astrophysical journal,
04/2004, Letnik:
605, Številka:
1
Journal Article
Recenzirano
Odprti dostop
We report interstellar C II column densities or upper limits determined from weak absorption of the 2325.4029 Aa intersystem transition observed in six translucent sight lines (A sub(V) > ~ 1) with ...the Space Telescope Imaging Spectrograph (STIS). The sight lines sample a wide range of interstellar characteristics, including total to selective extinction, R sub(V) = 2.6- 5.1; average hydrogen density along the sight line, ang10n(H)ang0 = 3-14 cm super(-3); and fraction of H in molecular form, 0-approx40%. Four of the sight lines, those toward HD 37021, HD 37061, HD 147888, and HD 207198, have interstellar gas-phase abundances that are consistent with the diffuse sight line ratio of 161 plus or minus 17 carbon atoms in the gas per million hydrogen nuclei. We note that while it has a gas-phase carbon abundance that is consistent with the other sight lines, a large fraction of the C II toward HD 37061 is in an excited state. The sight line toward HD 152590 has a measured interstellar gas-phase carbon abundance that is well above the diffuse sight line average; the column density of C in this sight line may be overestimated because of noise structure in the data. Toward HD 27778 we find a 3 capital sigma abundance upper limit of <108 C atoms in the gas per million H, a substantially enhanced depletion of C as compared to the diffuse sight line value. The interstellar characteristics toward HD 27778 are otherwise not extreme among the sample, except for an unusually large abundance of CO molecules in the gas.
The HIPASS catalogue – I. Data presentation Meyer, M. J.; Zwaan, M. A.; Webster, R. L. ...
Monthly Notices of the Royal Astronomical Society,
June 2004, Letnik:
350, Številka:
4
Journal Article
Recenzirano
Odprti dostop
The H i Parkes All-Sky Survey (HIPASS) catalogue forms the largest uniform catalogue of H i sources compiled to date, with 4315 sources identified purely by their H i content. The catalogue data ...comprise the southern region δ < + 2° of HIPASS, the first blind H i survey to cover the entire southern sky. The rms noise for this survey is 13 mJy beam −1 and the velocity range is −1280 to 12 700 km s −1. Data search, verification and parametrization methods are discussed along with a description of measured quantities. Full catalogue data are made available to the astronomical community including positions, velocities, velocity widths, integrated fluxes and peak flux densities. Also available are on-sky moment maps, position–velocity moment maps and spectra of catalogue sources. A number of local large-scale features are observed in the space distribution of sources, including the super-Galactic plane and the Local Void. Notably, large-scale structure is seen at low Galactic latitudes, a region normally obscured at optical wavelengths.
Abstract Objectives Dual-energy CT (DECT) allows quantification of intravenously injected iodinated contrast media in tumors, and therefore may be considered as a surrogate marker for perfusion and ...tumor vascularity. This study evaluated whether newly developed DECT response criteria allow better correlation with survival than established response criteria. Methods Seventeen patients with advanced GIST treated with tyrosine-kinase-inhibitors were assessed by contrast-enhanced DECT 2 and 6 months after beginning of treatment. Response to treatment of 165 tumor lesions was evaluated according to RECIST, Choi criteria and newly developed DECT criteria, defining non-responders as an increase of both tumor size >20% and iodine related attenuation or either a >50% increase of tumor size or iodine related attenuation. All other patients were classified as responders. Progression-free survival (PFS) and overall survival (OS) were calculated by Kaplan–Meier analysis. Results Choi criteria and DECT showed a significantly longer median PFS of patients rated as responders than patients rated as non-responders (9–29 months vs. 2–6 months; p < 0.02) at follow-up. Only DECT analysis at 6 months follow-up allowed a valid prediction of OS. Conclusion This study indicates that DECT allows a better prediction of therapeutic benefit in advanced GIST patients treated with tyrosine-kinase-inhibitors than established response criteria. However, the most important predictive biomarker of therapeutic benefit was absence of progression, no matter which response evaluation criteria were applied.
Abstract
Background
Host genetics can shape microbiome composition, but to what extent it does, remains unclear. Like any other complex trait, this important question can be addressed by estimating ...the heritability (
h
2
) of the microbiome—the proportion of variance in the abundance in each taxon that is attributable to host genetic variation. However, unlike most complex traits, microbiome heritability is typically based on relative abundance data, where taxon-specific abundances are expressed as the proportion of the total microbial abundance in a sample.
Results
We derived an analytical approximation for the heritability that one obtains when using such relative, and not absolute, abundances, based on an underlying quantitative genetic model for absolute abundances. Based on this, we uncovered three problems that can arise when using relative abundances to estimate microbiome heritability: (1) the interdependency between taxa can lead to imprecise heritability estimates. This problem is most apparent for dominant taxa. (2) Large sample size leads to high false discovery rates. With enough statistical power, the result is a strong overestimation of the number of heritable taxa in a community. (3) Microbial co-abundances lead to biased heritability estimates.
Conclusions
We discuss several potential solutions for advancing the field, focusing on technical and statistical developments, and conclude that caution must be taken when interpreting heritability estimates and comparing values across studies.
Many children do not engage in sufficient physical activity, and schools provide a unique venue for children to reach their recommended 60 daily minutes of moderate-to-vigorous physical activity ...(MVPA). Prior research examining effects of MVPA on academic achievement is inconclusive, and few studies have investigated potential moderators of this relationship. This study examined whether student-level characteristics (gender, race/ethnicity, free/reduced-price lunch status) and school-level characteristics (proportion of students qualifying for free/reduced-price lunch, physical activity environment and opportunities) moderate the relationship between MVPA and academic achievement. In a large, diverse metropolitan public school district in Georgia, 4,936 students in Grade 4 were recruited from 40 elementary schools. Students wore accelerometers to measure school-day MVPA for a total of 15 days across three semesters (fall 2018, spring 2019, fall 2019). Academic achievement data, including course marks (grades) for math, reading, spelling, and standardized test scores in writing, math, reading, and Lexile (reading assessment), were collected at baseline (Grade 3, ages 8-9) and at follow-up in Grade 4 (ages 9-10). Standardized test scores were not measured in Grade 5 (ages 10-11) due to COVID-19-related disruptions. Multilevel modeling assessed whether student-level and/or school-level characteristics were moderators in the cross-sectional and longitudinal MVPA-academic achievement relationship. Cross sectional analyses indicated that the MVPA and AA relationship was moderated only by student Hispanic ethnicity for Grade 4 fall spelling marks (beta = -0.159 p < 0.001). The relationship for Grade 4 fall spelling marks was also moderated by school physical activity opportunities (beta = -0.128 (p < 0.001). Longitudinally, there was no significant moderation of the MVPA-academic achievement. A relationship by student gender, free/reduced-price lunch status, race/ethnicity; nor for school-level factors including proportion of students qualifying for free/reduced-price lunch, physical activity environment, and physical activity opportunities. Overall, our results did not suggest that student- or school-level characteristics moderate the MVPA-academic achievement relationship. While statistically significant results were observed for certain outcomes, practical differences were negligible. In this population, school-based MVPA does not appear to differently affect academic performance based on student gender, race/ethnicity, free/reduced-price lunch, nor school characteristics.
Investigating the physical mechanisms driving the dynamical evolution of young star clusters is fundamental to our understanding of the star formation process and the properties of the Galactic field ...stars. The young (~2 Myr) and partially embedded cluster Chamaeleon I is one of the closest laboratories for the study of the early stages of star cluster dynamics in a low-density environment. The aim of this work is to study the structural and kinematical properties of this cluster combining parameters from the high-resolution spectroscopic observations of the Gaia-ESO Survey with data from the literature. Our main result is the evidence of a large discrepancy between the velocity dispersion (σstars = 1.14 ± 0.35 km s-1) of the stellar population and the dispersion of the pre-stellar cores (~0.3 km s-1) derived from submillimeter observations. The origin of this discrepancy, which has been observed in other young star clusters, is not clear. It has been suggested that it may be due to either the effect of the magnetic field on the protostars and the filaments or to the dynamical evolution of stars driven by two-body interactions. Furthermore, the analysis of the kinematic properties of the stellar population puts in evidence a significant velocity shift (~1 km s-1) between the two subclusters located around the north and south main clouds of the cluster. This result further supports a scenario where clusters form from the evolution of multiple substructures rather than from a monolithic collapse. Using three independent spectroscopic indicators (the gravity indicator γ, the equivalent width of the Li line at 6708 Å, and the Hα 10% width), we performed a new membership selection. We found six new cluster members all located in the outer region of the cluster, proving that Chamaeleon I is probably more extended than previously thought. Starting from the positions and masses of the cluster members, we derived the level of substructure Q, the surface density Σ, and the level of mass segregation ΛMSR of the cluster. The comparison between these structural properties and the results of N-body simulations suggests that the cluster formed in a low-density environment, in virial equilibrium or a supervirial state, and highly substructured.
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