16,865 research outputs found

    Cryogenic mirror analysis

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    Due to extraordinary distances scanned by modern telescopes, optical surfaces in such telescopes must be manufactured to unimaginable standards of perfection of a few thousandths of a centimeter. The detection of imperfections of less than 1/20 of a wavelength of light, for application in the building of the mirror for the Space Infrared Telescope Facility, was undertaken. Because the mirror must be kept very cold while in space, another factor comes into effect: cryogenics. The process to test a specific morror under cryogenic conditions is described; including the follow-up analysis accomplished through computer work. To better illustrate the process and analysis, a Pyrex Hex-Core mirror is followed through the process from the laser interferometry in the lab, to computer analysis via a computer program called FRINGE. This analysis via FRINGE is detailed

    Renormalization of the bilocal sine-Gordon model

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    The functional renormalization group treatment is presented for the two-dimensional sine-Gordon model by including a bilocal term in the potential, which contributes to the flow at tree level. It is shown that the flow of the bilocal term can substitute the evolution of the wave function renormalization constant, and then the Kosterlitz-Thouless type phase transition can be recovered.Comment: 16 pages, 2 figure

    Utilizing Community Resources to Reduce the Presence of Type 2 Diabetes in Rural Youth

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    The purpose of this study was to implement a program designed to promote diabetes prevention activities among preadolescents in a rural southern setting using a day camp intervention. Participants in the study were eleven youth from a rural Alabama county who participated in a week-long half-day camp administered by local and community volunteers. Change scores were used to compare pre- to post- to follow-up measures for camp participant responses. Program results consistently demonstrated that the day camp was theoretically sound and that program activities positively impacted behavioral antecedents. This study demonstrated the feasibility of conducting a diabetes prevention day camp in a rural environment. Insights from this intervention can assist planners in rural environments to tailor similar initiatives in rural settings. Given the complicated nature of behavior change, a day camp approach of this length does not modify the behaviors of participants. Behavior changes may take considerably longer to initiate
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