2,079 research outputs found

    Research into display sharing techniques for distributed computing environments

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    The X-based Display Sharing solution for distributed computing environments is described. The Display Sharing prototype includes the base functionality for telecast and display copy requirements. Since the prototype implementation is modular and the system design provided flexibility for the Mission Control Center Upgrade (MCCU) operational consideration, the prototype implementation can be the baseline for a production Display Sharing implementation. To facilitate the process the following discussions are presented: Theory of operation; System of architecture; Using the prototype; Software description; Research tools; Prototype evaluation; and Outstanding issues. The prototype is based on the concept of a dedicated central host performing the majority of the Display Sharing processing, allowing minimal impact on each individual workstation. Each workstation participating in Display Sharing hosts programs to facilitate the user's access to Display Sharing as host machine

    A rapid, chromatography-free route to substituted acridine–isoalloxazine conjugates under microwave irradiation

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    Microwave irradiation was applied to a sequence of condensation reactions from readily available 9-chloroacridines to provide a range of novel acridine–isoalloxazine conjugates. The combination of these two moieties, both of biological interest, was achieved by a chromatography free route

    Prevention, screening and treatment of colorectal cancer: a global and regional generalized cost effectiveness analysis

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    <p>Abstract</p> <p>Background</p> <p>Regional generalized cost-effectiveness estimates of prevention, screening and treatment interventions for colorectal cancer are presented.</p> <p>Methods</p> <p>Standardised WHO-CHOICE methodology was used. A colorectal cancer model was employed to provide estimates of screening and treatment effectiveness. Intervention effectiveness was determined via a population state-transition model (PopMod) that simulates the evolution of a sub-regional population accounting for births, deaths and disease epidemiology. Economic costs of procedures and treatment were estimated, including programme overhead and training costs.</p> <p>Results</p> <p>In regions characterised by high income, low mortality and high existing treatment coverage, the addition of screening to the current high treatment levels is very cost-effective, although no particular intervention stands out in cost-effectiveness terms relative to the others.</p> <p>In regions characterised by low income, low mortality with existing treatment coverage around 50%, expanding treatment with or without screening is cost-effective or very cost-effective. Abandoning treatment in favour of screening (no treatment scenario) would not be cost effective.</p> <p>In regions characterised by low income, high mortality and low treatment levels, the most cost-effective intervention is expanding treatment.</p> <p>Conclusions</p> <p>From a cost-effectiveness standpoint, screening programmes should be expanded in developed regions and treatment programmes should be established for colorectal cancer in regions with low treatment coverage.</p

    Growth of the adult goldfish eye--I: Optics

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    We have measured the optical and retinal fields of goldfish eyes; the animals ranged from 6 to 20 cm in body length. Both fields are spherically symmetric, invariant with the size of the eye, and equal (retinal FIELD = 185.3[deg] +/- 4.1[deg], optical FIELD = 183.6[deg] +/- 2.7[deg], means +/- S.D.). They are tilted with respect to one another by a few (< 10) degrees. We have also measured the retinal magnification factor, the number of [mu]m per degree on the retinal surface. It is 20.5 x lens diameter, where lens diameter is expressed in mm.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23062/1/0000634.pd

    Determining Optimum Soil Type and Salinity for Rearing the Federally Endangered Salt Creek Tiger Beetle, \u3ci\u3eCicindela (Ellipsoptera) nevadica lincolniana\u3c/i\u3e Casey (Coleoptera: Carabidae: Cicindelinae)

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    Effective rearing methods are needed to recover the federally endangered Salt Creek tiger beetle, Cicindela (Ellipsoptera) nevadica lincolniana Casey, a subspecies that occurs exclusively in saline wetlands and seeps along Little Salt Creek in Lancaster County, Nebraska. Experiments were initiated to determine soil type and salinity concentrations appropriate for stimulating female oviposition in laboratory settings to produce larvae and/or adults for reintroduction to native habitats. In 2013, there were highly significant differences between native soil and a sand/loess soil mixture, but no differences between two salinity levels, 0.354 M and 0.5 M. In 2014, using only a sand/loess soil mixture, there were again no differences between the test salinity levels. A sand/loess soil mixture of either 0.354M or 0.5M salinity was determined to be optimum for egg production

    Determining Optimum Soil Type and Salinity for Rearing the Federally Endangered Salt Creek Tiger Beetle, \u3ci\u3eCicindela (Ellipsoptera) nevadica lincolniana\u3c/i\u3e Casey (Coleoptera: Carabidae: Cicindelinae)

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    Effective rearing methods are needed to recover the federally endangered Salt Creek tiger beetle, Cicindela (Ellipsoptera) nevadica lincolniana Casey, a subspecies that occurs exclusively in saline wetlands and seeps along Little Salt Creek in Lancaster County, Nebraska. Experiments were initiated to determine soil type and salinity concentrations appropriate for stimulating female oviposition in laboratory settings to produce larvae and/or adults for reintroduction to native habitats. In 2013, there were highly significant differences between native soil and a sand/loess soil mixture, but no differences between two salinity levels, 0.354 M and 0.5 M. In 2014, using only a sand/loess soil mixture, there were again no differences between the test salinity levels. A sand/loess soil mixture of either 0.354M or 0.5M salinity was determined to be optimum for egg production

    Discovery of a Low-Mass Companion to the Solar-Type Star TYC 2534-698-1

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    Brown dwarfs and low-mass stellar companions are interesting objects to study since they occupy the mass region between deuterium and hydrogen burning. We report here the serendipitous discovery of a low-mass companion in an eccentric orbit around a solar-type main sequence star. The stellar primary, TYC 2534-698-1, is a G2V star that was monitored both spectroscopically and photometrically over the course of several months. Radial velocity observations indicate a minimum mass of 0.037 M_solar and an orbital period of ~103 days for the companion. Photometry outside of the transit window shows the star to be stable to within ~6 millimags. The semi-major axis of the orbit places the companion in the 'brown dwarf desert' and we discuss potential follow-up observations that could constrain the mass of the companion.Comment: 6 pages, 8 figures, accepted for publication in Ap

    The Transit Ingress and the Tilted Orbit of the Extraordinarily Eccentric Exoplanet HD 80606b

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    We present the results of a transcontinental campaign to observe the 2009 June 5 transit of the exoplanet HD 80606b. We report the first detection of the transit ingress, revealing the transit duration to be 11.64 +/- 0.25 hr and allowing more robust determinations of the system parameters. Keck spectra obtained at midtransit exhibit an anomalous blueshift, giving definitive evidence that the stellar spin axis and planetary orbital axis are misaligned. The Keck data show that the projected spin-orbit angle is between 32-87 deg with 68.3% confidence and between 14-142 deg with 99.73% confidence. Thus the orbit of this planet is not only highly eccentric (e=0.93), but is also tilted away from the equatorial plane of its parent star. A large tilt had been predicted, based on the idea that the planet's eccentric orbit was caused by the Kozai mechanism. Independently of the theory, it is noteworthy that all 3 exoplanetary systems with known spin-orbit misalignments have massive planets on eccentric orbits, suggesting that those systems migrate differently than lower-mass planets on circular orbits.Comment: ApJ, in press [13 pg

    LSST: from Science Drivers to Reference Design and Anticipated Data Products

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    (Abridged) We describe here the most ambitious survey currently planned in the optical, the Large Synoptic Survey Telescope (LSST). A vast array of science will be enabled by a single wide-deep-fast sky survey, and LSST will have unique survey capability in the faint time domain. The LSST design is driven by four main science themes: probing dark energy and dark matter, taking an inventory of the Solar System, exploring the transient optical sky, and mapping the Milky Way. LSST will be a wide-field ground-based system sited at Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m effective) primary mirror, a 9.6 deg2^2 field of view, and a 3.2 Gigapixel camera. The standard observing sequence will consist of pairs of 15-second exposures in a given field, with two such visits in each pointing in a given night. With these repeats, the LSST system is capable of imaging about 10,000 square degrees of sky in a single filter in three nights. The typical 5σ\sigma point-source depth in a single visit in rr will be ∌24.5\sim 24.5 (AB). The project is in the construction phase and will begin regular survey operations by 2022. The survey area will be contained within 30,000 deg2^2 with ÎŽ<+34.5∘\delta<+34.5^\circ, and will be imaged multiple times in six bands, ugrizyugrizy, covering the wavelength range 320--1050 nm. About 90\% of the observing time will be devoted to a deep-wide-fast survey mode which will uniformly observe a 18,000 deg2^2 region about 800 times (summed over all six bands) during the anticipated 10 years of operations, and yield a coadded map to r∌27.5r\sim27.5. The remaining 10\% of the observing time will be allocated to projects such as a Very Deep and Fast time domain survey. The goal is to make LSST data products, including a relational database of about 32 trillion observations of 40 billion objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures available from https://www.lsst.org/overvie
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