716 research outputs found

    The school nurse role in a special education program

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    Symplectic Geometry of Supersymmetry and Nonlinear Sigma Model

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    Recently it has been argued, that Poincar\'{e} supersymmetric field theories admit an underlying loop space hamiltonian (symplectic) structure. Here shall establish this at the level of a general N=1N=1 supermultiplet. In particular, we advocate the use of a superloop space and explain the necessity of using nonconventional auxiliary fields. As an example we consider the nonlinear σ\sigma-model. Due to the quartic fermionic term, we conclude that the use of superloop space variables is necessary for the action to have a hamiltonian loop space interpretation.Comment: 9 pages, UU-ITP 30/9

    Columbus IFHX Ammonia Leak Analysis

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    After the Columbus Moderate Temperature Loop (MTL) InterFace Heat eXchanger (IFHX) low temperature event of GMT 345-2013, NASA investigated relevant transient scenarios involving IFHX rupture after water freezing and subsequent thawing. NASA recommended development of a Fault Detection Isolation and Recovery (FDIR) plan that would, in the event of a heat exchanger freeze event, close the Water On/Off Valves (WOOVs) to isolate the heat exchanger and prevent ammonia from the external flow loops from spreading into the cabin. NASA performed a preliminary simplified analysis for the reference case of IFHX rupture, but for a deeper understanding TAS developed detailed SINDA-FLUINT models of the Columbus ITCS that were built and run through the SINAPS GUI. This allowed simulation of the ammonia leakage physics including the variation of environmental parameters, thus providing more accurate and specific input to the FDIR under development. The result was finalization of the IFHX WOOVs closure sequence and wait times to contain the ammonia propagation to Columbus and allow identification of the leaking IFHX. In addition, the analysis results provided reference pressure profiles to be used on console and by the Engineering as support for the telemetry data assessment in case of failure.This paper gives an overview on the issue and focuses on the analytical aspects of the multiphase fluid dynamics involved

    Integrated Self-Assembly of the Mms6 Magnetosome Protein to Form an Iron-Responsive Structure

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    A common feature of biomineralization proteins is their self-assembly to produce a surface consistent in size with the inorganic crystals that they produce. Mms6, a small protein of 60 amino acids from Magnetospirillum magneticum strain AMB-1 that promotes the in vitro growth of superparamagnetic magnetite nanocrystals, assembles in aqueous solution to form spherical micelles that could be visualized by TEM and AFM. The results reported here are consistent with the view that the N and C-terminal domains interact with each other within one polypeptide chain and across protein units in the assembly. From studies to determine the amino acid residues important for self-assembly, we identified the unique GL repeat in the N-terminal domain with additional contributions from amino acids in other positions, throughout the molecule. Analysis by CD spectroscopy identified a structural change in the iron-binding C-terminal domain in the presence of Fe3+. A change in the intrinsic fluorescence of tryptophan in the N-terminal domain showed that this structural change is transmitted through the protein. Thus, self-assembly of Mms6 involves an interlaced structure of intra- and inter-molecular interactions that results in a coordinated structural change in the protein assembly with iron binding

    Effect of lifestyle changes on erectile dysfunction in obese men: a randomized controlled trial

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    Context: Healthy lifestyle factors are associated with maintenance of erectile function in men. Objective: To determine the effect of weight loss and increased physical activity on erectile and endothelial functions in obese men. Design, Setting, and Patients: Randomized, single-blind trial of 110 obese men (body mass index ≥30) aged 35 to 55 years, without diabetes, hypertension, or hyperlipidemia, who had erectile dysfunction that was determined by having a score of 21 or less on the International Index of Erectile Function (IIEF). The study was conducted from October 2000 to October 2003 at a university hospital in Italy. Interventions: The 55 men randomly assigned to the intervention group received detailed advice about how to achieve a loss of 10% or more in their total body weight by reducing caloric intake and increasing their level of physical activity. Men in the control group (n=55) were given general information about healthy food choices and exercise. Main Outcomes Measures: Erectile function score, levels of cholesterol and tryglycerides, circulating levels of interleukin 6, interleukin 8, and C-reactive protein, and endothelial function as assessed by vascular responses to L-arginine. Results: After 2 years, body mass index decreased more in the intervention group (from a mean [SD] of 36.9 [2.5] to 31.2 [2.1]) than in the control group (from 36.4 [2.3] to 35.7 [2.5]) (P<.001), as did serum concentrations of interleukin 6 (P=.03), and C-reactive protein (P=.02). The mean (SD) level of physical activity increased more in the intervention group (from 48 [10] to 195 [36] min/wk; P<.001) than in the control group (from 51 [9] to 84 [28] min/wk; P<.001). The mean (SD) IIEF score improved in the intervention group (from 13.9 [4.0] to 17 [5]; P<.001), but remained stable in the control group (from 13.5 [4.0] to 13.6 [4.1]; P=.89). Seventeen men in the intervention group and 3 in the control group (P=.001) reported an IIEF score of 22 or higher. In multivariate analyses, changes in body mass index (P=.02), physical activity (P=.02), and C-reactive protein (P=.03) were independently associated with changes in IIEF score. Conclusion: Lifestyle changes are associated with improvement in sexual function in about one third of obese men with erectile dysfunction at baseline

    PdZnAl Catalysts for the Reactions of Water-Gas-Shift, Methanol Steam Reforming, and Reverse-Water-Gas-Shift

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    Pd/ZnO/Al2O3 catalysts were studied for water-gas-shift (WGS), methanol steam reforming, and reverse-water-gas-shift (RWGS) reactions. WGS activity was found to be dependent on the Pd:Zn ratio with a maximum activity obtained at approximately 0.50, which was comparable to that of a commercial Pt-based catalyst. The catalyst stability was demonstrated for 100 hours time-on-stream at a temperature of 360ºC without evidence of metal sintering. WGS reaction rates were approximately 1st order with respect to CO concentration, and kinetic parameters were determined to be Ea = 58.3 kJ mol-1 and k0 = 6.1x107 min-1. During methanol steam reforming, the CO selectivities were observed to be lower than the calculated equilibrium values over a range of temperatures and steam/carbon ratios studied while the reaction rate constants were approximately of the same magnitude for both WGS and methanol steam reforming. These results indicate that although Pd/ZnO/Al2O3 are active WGS catalysts, WGS is not involved in methanol steam reforming. RWGS rate constants are on the order of about 20 times lower than that of methanol steam reforming, suggesting that RWGS reaction could be one of the sources for small amount of CO formation in methanol steam reforming

    Papers of the Second Palo Alto Conference

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    Introduction -- Conference Program -- Reconsideraciones sobre la guerra entre México y los Estados Unidos / Josefina Zoraida Vázquez -- La beligerencia mexicana durante la guerra con los Estados Unidos/ Jesús Velasco -Márquez -- James K. Polk and Presidential War Powers: An Unexplored Field of the Constitution / Kathleen O\u27Kray Peltier -- A Thread of Brittle Texture : Ann Chase and Manifest Destiny / Shannon L. Baker -- We Shall Beat Them Wherever We Meet Them : Civil War Officer Perceptions of Mexico; 1846-48 / Christopher S. Stowe -- Encountering the Other: American Soldiers in the Mexican - American War, 1846-48 / Frank F. Koscielski -- War Correspondents on the Rio Grande: The Press and America\u27s First Foreign War / Mitchel Roth -- Women and the Mexican War / Linda Vance -- The Immigrant Soldier in the Regular Army During the Mexican War / Dale R. Steinhauer -- The Regiment of Voltigeurs, U.S.A .: A Case Study of the Mexican - American War / Erik D. France -- Mr. Polk\u27s Generals / Richard Bruce Winders -- Cerro Gordo Shout : David E. Twiggs and the United States Mexican War / Jeanne T. Heidler & David S. Heidler -- Buena Vista : All Wool and a Mile Wide / Bob Burk -- The New Mexican Revolt of 1847 and its Effect on American Jurisprudence, 1850-1912 / Robert J. Torrez -- Ho! For Yucatan ! : Los voluntarios norteamericanos después de la guerra con México / Lorena Careaga Viliesid -- Josiah Turner, Juan Cortina, and Carlos Esparza: Veterans of the Mexican War Along the Lower Rio Grande / Carlos Larralde -- The Texas Devils: McNelly\u27s Rangers and the Palo Alto Fight of 1875 / Michael Collins -- Biology of the Palo Alto Battlefield Site: A Summary / Norman L. Richard & Alfred Richardson -- Palo Alto : A Symbol and Sacred Ground / Joseph O\u27Bell
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