9,948 research outputs found

    Alfalfa Snout Beetle, \u3ci\u3eOtiorhynchus Ligustici\u3c/i\u3e L. (Coleoptera: Curculionidae): Methods for Egg Collection and Larval Rearing

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    The alfalfa snout beetle, Otiorhynchus ligustici L., is the most serious pest of alfalfa in northern New York State. Recent research efforts focused on the biological control of this insect require the availability of all life stages. With a 2-year lifecycle and a mandatory diapause, the artificial rearing of a laboratory culture appears to be a non-viable option at present, but methods described here can be used to obtain sufficient numbers of eggs and larvae over an extended period of time for research purposes. The crowding of adult beetles in egg production units (cups) had a significant, negative effect on egg production per beetle but the total egg production per cup was still higher with higher number of beetles per cup resulting in a significant saving of labor per egg produced. Larval survival rates in alfalfa-planted cans were surprisingly low given the protected conditions of the greenhouse. The larval survival rates were not significantly different among the dates for the second instar and later instars, suggesting that larval mortality occurs in the first instar in alfalfa-planted cans

    Wheelchair-based game design for older adults

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    Few leisure activities are accessible to institutionalized older adults using wheelchairs; in consequence, they experience lower levels of perceived health than able-bodied peers. Video games have been shown to be an engaging leisure activity for older adults. In our work, we address the design of wheelchair-accessible motion-based games. We present KINECTWheels, a toolkit designed to integrate wheelchair movements into motion-based games, and Cupcake Heaven, a wheelchair-based video game designed for older adults using wheelchairs. Results of two studies show that KINECTWheels can be applied to make motion-based games wheelchair-accessible, and that wheelchair-based games engage older adults. Through the application of the wheelchair as an enabling technology in play, our work has the potential of encouraging older adults to develop a positive relationship with their wheelchair. Copyright 2013 ACM

    Technology benefits and ground test facilities for high-speed civil transport development

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    The advanced technology base necessary for successful twenty-first century High-Speed Civil Transport (HSCT) aircraft will require extensive ground testing in aerodynamics, propulsion, acoustics, structures, materials, and other disciplines. This paper analyzes the benefits of advanced technology application to HSCT concepts, addresses the adequacy of existing groundbased test facilities, and explores the need for new facilities required to support HSCT development. A substantial amount of HSCT-related ground testing can be accomplished in existing facilities. The HSCT development effort could also benefit significantly from some new facilities initially conceived for testing in other aeronautical research areas. A new structures testing facility is identified as critically needed to insure timely technology maturation

    Free induction decay of a superposition stored in a quantum dot

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    We study the free evolution of a superposition initialized with high fidelity in the neutral-exciton state of a quantum dot. Readout of the state at later times is achieved by polarized photon detection, averaged over a large number of cycles. By controlling the fine-structure splitting (FSS) of the dot with a dc electric field, we show a reduction in the degree of polarization of the signal when the splitting is minimized. In analogy with the "free induction decay" observed in nuclear magnetic resonance, we attribute this to hyperfine interactions with nuclei in the semiconductor. We numerically model this effect and find good agreement with experimental studies. Our findings have implications for storage of superpositions in solid-state systems and for entangled photon pair emission protocols that require a small value of the FSS

    Quasar outflow energetics from broad absorption line variability

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    Quasar outflows have long been recognized as potential contributors to the co-evolution between supermassive black holes (SMBHs) and their host galaxies. The role of outflows in AGN feedback processes can be better understood by placing observational constraints on wind locations and kinetic energies. We utilize broad absorption line (BAL) variability to investigate the properties of a sample of 71 BAL quasars with P\thinspaceV broad absorption. The presence of P\thinspaceV BALs indicates that other BALs like C\thinspaceIV are saturated, such that variability in those lines favours clouds crossing the line of sight. We use these constraints with measurements of BAL variability to estimate outflow locations and energetics. Our data set consists of multiple-epoch spectra from the Sloan Digital Sky Survey and MDM Observatory. We detect significant (4σ\sigma) BAL variations from 10 quasars in our sample over rest frame time-scales between < 0.2-3.8 yr. Our derived distances for the 10 variable outflows are nominally < 1-10 pc from the SMBH using the transverse-motion scenario, and < 100-1000 pc from the central source using ionization-change considerations. These distances, in combination with the estimated high outflow column densities (i.e. NHN_{\textrm{H}} > 1022^{22} cm2^{-2}), yield outflow kinetic luminosities between ~ 0.001-1 times the bolometric luminosity of the quasar, indicating that many absorber energies within our sample are viable for AGN feedback.Comment: 19 pages, 3 figures, 4 tables, 1 supplementary figure, accepted to MNRA
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