257 research outputs found

    Measuring and changing negative stuttering stereotypes in adolescents

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    Stuttering is known to carry stereotypes, e.g., that people who stutter are nervous, anxious, and shy. Research has shown that negative stereotypes about people who stutter exist within the general population. Moreover, negative stereotypes exist among teachers, students, speech-language pathologists, and even the parents of people who stutter. While public opinion of stuttering does not vary dramatically between populations, the ways in which we might change it does. Research has shown that educational videos, books, and classes about stuttering do not appear to significantly alter public opinion positively.;This study compared the effectiveness of two forms of advocacy, a live presentation versus a video presentation, in altering the stuttering stereotype among adolescents. Participants filled out a questionnaire before they were exposed to a 45-minute live presentation or a 45-minute video presentation. After these live and video presentations, they completed a second questionnaire. Then, participants who watched the video were exposed to a shortened 20-minute live presentation followed by a third and final questionnaire.;Results indicated that adolescents showed evidence of negative stereotypes towards people who stutter prior to the presentations. Overall, there were 27 significant positive attitude changes towards stuttering (p \u3c 0.005), 15 for live presentations and 12 for video presentations. Five additional significant positive attitude changes occurred after the video presentation as a result of the shortened live presentation. These findings demonstrate that adolescents\u27 opinions on stuttering can be altered in a positive direction. A live presentation appears to have a greater positive impact on altering attitudes than a video presentation, and moreover, a shortened live presentation following a video presentation can further alter attitudes positively

    Spontaneous induction of the uniform lying helix alignment in bimesogenic liquid crystals for the flexoelectro-optic effect

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    Using in-plane electric fields, the electrical induction of the uniform lying helix (ULH) alignment in chiral nematic liquid crystals is reported. This process permits spontaneous induction of the ULH alignment to give an in-plane optic axis, without the need for complex processing. Flexoelectro-optic switching is subsequently obtained by holding the in-plane electrodes at a common voltage and addressing via a third, plane-parallel electrode on a second, or upper, substrate to give a field across the device in the viewing direction. For this device, in optimized bimesogenic materials, we demonstrate full intensity modulation and sub-millisecond response times at typical device temperatures. (C) 2012 American Institute of Physics. [doi:10.1063/1.3682305]11Nsciescopu

    The vertical motions of mono-abundance sub-populations in the Milky Way disk

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    We present the vertical kinematics of stars in the Milky Way's stellar disk inferred from SDSS/SEGUE G-dwarf data, deriving the vertical velocity dispersion, \sigma_z, as a function of vertical height |z| and Galactocentric radius R for a set of 'mono-abundance' sub-populations of stars with very similar elemental abundances [\alpha/Fe] and [Fe/H]. We find that all components exhibit nearly isothermal kinematics in |z|, and a slow outward decrease of the vertical velocity dispersion: \sigma_z (z,R|[\alpha/Fe],[Fe/H]) ~ \sigma_z ([\alpha/Fe],[Fe/H]) x \exp (-(R-R_0)/7 kpc}). The characteristic velocity dispersions of these components vary from ~ 15 km/s for chemically young, metal-rich stars, to >~ 50 km/s for metal poor stars. The mean \sigma_z gradient away from the mid plane is only 0.3 +/- 0.2 km/s/kpc. We find a continuum of vertical kinetic temperatures (~\sigma^2_z) as function of ([\alpha/Fe],[Fe/H]), which contribute to the stellar surface mass density as \Sigma_{R_0}(\sigma^2_z) ~ \exp(-\sigma^2_z). The existence of isothermal mono-abundance populations with intermediate dispersions reject the notion of a thin-thick disk dichotomy. This continuum of disks argues against models where the thicker disk portions arise from massive satellite infall or heating; scenarios where either the oldest disk portion was born hot, or where internal evolution plays a major role, seem the most viable. The wide range of \sigma_z ([\alpha/Fe],[Fe/H]) combined with a constant \sigma_z(z) for each abundance bin provides an independent check on the precision of the SEGUE abundances: \delta_[\alpha/Fe] ~ 0.07 dex and \delta_[Fe/H] ~ 0.15 dex. The radial decline of the vertical dispersion presumably reflects the decrease in disk surface-mass density. This measurement constitutes a first step toward a purely dynamical estimate of the mass profile the disk in our Galaxy. [abridged

    PII: S0167-7799(00)01511-0

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    This article summarizes recent advances in the field of algal hydrogen production. Two fundamental approaches are being developed. One involves the temporal separation of the usually incompatible reactions of O 2 and H 2 production in green algae, and the second involves the use of classical genetics to increase the O 2 tolerance of the reversible hydrogenase enzyme. The economic and environmental impact of a renewable source of H 2 are also discussed

    Detection of a glitch in the pulsar J1709-4429

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    We report the detection of a glitch event in the pulsar J1709−-4429 (also known as B1706−-44) during regular monitoring observations with the Molonglo Observatory Synthesis Telescope (UTMOST). The glitch was found during timing operations, in which we regularly observe over 400 pulsars with up to daily cadence, while commensally searching for Rotating Radio Transients, pulsars, and FRBs. With a fractional size of ΔΜ/Μ≈52.4×10−9\Delta\nu/\nu \approx 52.4 \times10^{-9}, the glitch reported here is by far the smallest known for this pulsar, attesting to the efficacy of glitch searches with high cadence using UTMOST.Comment: 3 pages, 1 figur

    Differences in BVOC oxidation and SOA formation above and below the forest canopy

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    Gas-phase biogenic volatile organic compounds (BVOCs) are oxidized in the troposphere to produce secondary pollutants such as ozone (O3), organic nitrates (RONO2), and secondary organic aerosol (SOA). Two coupled zero-dimensional models have been used to investigate differences in oxidation and SOA production from isoprene and α-pinene, especially with respect to the nitrate radical (NO3), above and below a forest canopy in rural Michigan. In both modeled environments (above and below the canopy), NO3 mixing ratios are relatively small (< 0.5 pptv); however, daytime (08:00–20:00 LT) mixing ratios below the canopy are 2 to 3 times larger than those above. As a result of this difference, NO3 contributes 12 % of total daytime α-pinene oxidation below the canopy while only contributing 4 % above. Increasing background pollutant levels to simulate a more polluted suburban or peri-urban forest environment increases the average contribution of NO3 to daytime below-canopy α-pinene oxidation to 32 %. Gas-phase RONO2 produced through NO3 oxidation undergoes net transport upward from the below-canopy environment during the day, and this transport contributes up to 30 % of total NO3-derived RONO2 production above the canopy in the morning (∌ 07:00). Modeled SOA mass loadings above and below the canopy ultimately differ by less than 0.5 ”g m−3, and extremely low-volatility organic compounds dominate SOA composition. Lower temperatures below the canopy cause increased partitioning of semi-volatile gas-phase products to the particle phase and up to 35 % larger SOA mass loadings of these products relative to above the canopy in the model. Including transport between above- and below-canopy environments increases above-canopy NO3-derived α-pinene RONO2 SOA mass by as much as 45 %, suggesting that below-canopy chemical processes substantially influence above-canopy SOA mass loadings, especially with regard to monoterpene-derived RONO2

    Intravitreal injection analysis at the Bascom Palmer Eye Institute: evaluation of clinical indications for the treatment and incidence rates of endophthalmitis

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    To report the incidence of endophthalmitis, in addition to its clinical and microbiological aspects, after intravitreal injection of vascular-targeting agents. A retrospective review of a consecutive series of 10,142 intravitreal injections of vascular targeting agents (bevacizumab, ranibizumab, triamcinolone acetonide, and preservative-free triamcinolone acetonide) between June 1, 2007 and January 31, 2010, performed by a single service (TGM) at the Bascom Palmer Eye Institute. One case of clinically-suspected endophthalmitis was identified out of a total of 10,142 injections (0.009%), presenting within three days of injection of bevacizumab. The case was culture-positive for Staphylococcus epidermidis. Final visual acuity was 20/40 after pars plana vitrectomy surgery. In this series, the incidence of culture-positive endophthalmitis after intravitreal injection of vascular agents in an outpatient setting was very low. We believe that following a standardized injection protocol, adherence to sterile techniques and proper patient follow-up are determining factors for low incidence rates
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