7,147 research outputs found

    Disproportionate Impact Of K-12 School Suspension And Expulsion On Black Students In Southern States

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    This report aims to make transparent the rates at which school discipline practices and policies impact Black students in every K-12 public school district in 13 Southern states: Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Texas, Virginia, and West Virginia

    Heterogeneity in 12^{12}CO/13^{13}CO Ratios Toward Solar-Type Young Stellar Objects

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    This study reports an unusual heterogeneity in [12^{12}C16^{16}O]/[13^{13}C16^{16}O] abundance ratios of carbon monoxide observed in the gas phase toward seven ~ solar-mass YSOs and three dense foreground clouds in the nearby star-forming regions, Ophiuchus, Corona Australis, Orion, Vela and an isolated core, L43. Robust isotope ratios were derived using infrared absorption spectroscopy of the 4.7 ÎŒ\mum fundamental and 2.3 ÎŒ\mum overtone rovibrational bands of CO at very high resolution (λ\lambda/Δ\Deltaλ≈95,000\lambda\approx 95,000), observed with the CRIRES spectrograph on the Very Large Telescope. We find [12^{12}C16^{16}O]/[13^{13}C16^{16}O] values ranging from ~ 85 to 165, significantly higher than those of the local interstellar medium (~ 65 to 69). These observations are evidence for isotopic heterogeneity in carbon reservoirs in solar-type YSO environments, and encourage the need for refined Galactic chemical evolution models to explain the 12^{12}C/13^{13}C discrepancy between the solar system and local ISM. The oxygen isotope ratios are consistent with isotopologue-specific photodissociation by CO self-shielding toward the disks, VV CrA N and HL Tau, further substantiating models predicting CO self-shielding on disk surfaces. However, we find that CO self-shielding is an unlikely general explanation for the high [12^{12}C16^{16}O]/[13^{13}C16^{16}O] ratios observed in this study. Comparison of the solid CO against gas-phase [12^{12}C16^{16}O]/[13^{13}C16^{16}O] suggests that interactions between CO ice and gas reservoirs need to be further investigated as at least a partial explanation for the unusually high [12^{12}C16^{16}O]/[13^{13}C16^{16}O] observed.Comment: 16 pages, 14 figures, 7 tables. Accepted for publication in The Astrophysical Journa

    Being Prepared and Staying Connected: Scouting’s Influence on Social Capital and Community Involvement

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    Objectives In recent years, scholars have become concerned about the effects that declining levels of social capital are having on community life in the United States. Data suggest that Americans are less likely to interact with neighbors and less likely to participate in community groups than they were in the past. Nevertheless, researchers have found that participation in some types of organizations has a positive impact on social capital and civic involvement. Each year, millions of American youth participate in programs designed to promote positive youth development. Here, we examine the effect that participation in one of the largest youth organizations, the Boy Scouts of America (BSA), has on adult social capital and community involvement. Methods Utilizing a national survey of adult males, we compare measures of social capital and community involvement for former Scouts and non‐Scouts. Results Our findings suggest that level of involvement in the Boy Scouts is significantly related to measures of adult social capital and community engagement. Conclusion Scouting tends to have a significant impact on the lives of its most committed members. Future research must continue to explore the long‐term effects of participation in youth organizations

    A Physiological Light Trap

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/119117/1/ecy1953341223.pd

    Bees, Daphnia, and Polarized Light

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/119098/1/ecy1960412360.pd
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