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Now showing items 65 - 80 of 2749

  • NSAIDs for high-risk patients: none, celecoxib, or naproxen?

    McGettigan, Patricia   Olsen, Anne-Marie Schjerning  

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  • Commentary: looking for conflict and finding none?

    Kaiser   M.  

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  • CALIOP and AERONET aerosol optical depth comparisons: One size fits none

    A. H. Omar   D. M. Winker   J. L. Tackett   D. M. Giles   J. Kar   Z. Liu   M. A. Vaughan   K. A. Powell and C. R. Trepte  

    [1] We compare the aerosol optical depths (AOD) retrieved from backscatter measurements of the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) aboard the Cloud Aerosol Lidar Infrared Pathfinder Satellite Observations (CALIPSO) satellite with coincident Aerosol Robotic Network (AERONET) measurements. Overpass coincidence criteria of ±2 h and within a 40 km radius are satisfied at least once at 149 globally distributed AERONET sites from 2006 to 2010. Most data pairs (>80%) use AERONET measurements acquired ±30 min of the overpass. We examine the differences in AOD estimates between CALIOP and AERONET for various aerosol, environmental, and geographic conditions. Results show CALIOP AOD are lower than AERONET AOD especially at low optical depths as measured by AERONET (500 nm AOD < 0.1). Furthermore, the median relative AOD difference between the two measurements is 25% of the AERONET AOD for AOD > 0.1. Differences in AOD between CALIOP and AERONET are possibly due to cloud contamination, scene inhomogeneity, instrument view angle differences, CALIOP retrieval errors, and detection limits. Comparison of daytime to nighttime number of 5 km × 60 m (60 m in the vertical) features detected by CALIOP show that there are 20% more aerosol features at night. We find that CALIPSO and AERONET do not agree on the cloudiness of scenes. Of the scenes that meet the above coincidence criteria, CALIPSO finds clouds in more than 45% of the coincident atmospheric columns AERONET classifies as clear.
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  • Flow injection analysis: An approach via linear none equilibrium thermodynamics

    Kuznetsov   Vladimir V.  

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  • None of the Rotor Residues of F1-ATPase Are Essential for Torque Generation

    Chiwata, Ryohei   Kohori, Ayako   Kawakami, Tomonari   Shiroguchi, Katsuyuki   Furuike, Shou   Adachi, Kengo   Sutoh, Kazuo   Yoshida, Masasuke   Kinosita, Kazuhiko  

    F-1-ATPase is a powerful rotary molecular motor that can rotate an object several hundred times as large as the motor itself against the viscous friction of water. Forced reverse rotation has been shown to lead to ATP synthesis, implying that the mechanical work against the motor's high torque can be converted into the chemical energy of ATP. The minimal composition of the motor protein is alpha(3)beta(3)gamma subunits, where the central rotor subunit gamma turns inside a stator cylinder made of alternately arranged alpha(3)beta(3) subunits using the energy derived from ATP hydrolysis. The rotor consists of an axle, a coiled coil of the amino- and carboxyl-terminal alpha-helices of gamma, which deeply penetrates the stator cylinder, and a globular protrusion that juts out from the stator. Previous work has shown that, for a thermophilic F-1, significant portions of the axle can be truncated and the motor still rotates a submicron sized bead duplex, indicating generation of up to half the wild-type (WT) torque. Here, we inquire if any specific interactions between the stator and the rest of the rotor are needed for the generation of a sizable torque. We truncated the protruding portion of the rotor and replaced part of the remaining axle residues such that every residue of the rotor has been deleted or replaced in this or previous truncation mutants. This protrusionless construct showed an unloaded rotary speed about a quarter of the WT, and generated one-third to one-half of the WT torque. No residue-specific interactions are needed for this much performance. F-1 is so designed that the basic rotor-stator interactions for torque generation and control of catalysis rely solely upon the shape and size of the rotor at very low resolution. Additional tailored interactions augment the torque to allow ATP synthesis under physiological conditions.
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  • Second to None: Plant Secondary siRNAs as Defensive Agents against Phytophthora

    Axtell, Michael J.  

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  • None but Myself Shall Play the Changeling”:

    Regina Buccola  

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  • 鈥淗igh-Tech”Antitrust: Incoherent, Misguided, Obsolete, or None of the Above? Comments on Crandall-Jackson and Wright

    Timothy J. Brennan  

    That prominent antitrust cases have been in the “high-tech” arena is not surprising, since high-tech industries are often susceptible to the scale economies that lead to highly concentrated or monopoly markets. Crandall and Jackson’s observations on the IBM case are on point. Regarding AT&T, the salient observation is that recent changes in legal doctrine may make it impossible to bring antitrust cases in regulated industries. The problem with the Microsoft case was not that it was right or wrong, but that it was fundamentally incoherent. Wright’s critique of the Federal Trade Commission’s case against Intel is problematic because buyers in exclusion cases tend to be better off, not victims as they would be under collusion or anticompetitive mergers. As these observations apply more generally to cases in sectors that are not associated with high-tech, I offer a few thoughts on some antitrust issues that are particular to high-tech sectors, specifically how the prospect of innovation could affect market definition in merger cases and, more broadly, whether dynamic efficiencies reduce the need for antitrust enforcement.
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  • Master of None: Trump, Jerusalem and the Prospects of Israeli-Palestinian Peace

    Eriksson Jacob  

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  • A Book for None? Teaching Biblical Studies to Millennial Nones

    Reed   Randall  

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  • Political Ideology in American Politics: One, Two, or None?

    Carmines, Edward G.   Ensley, Michael J.   Wagner, Michael W.  

    Are Americans ideological, and if so, what are the foundations of their ideology? According to Converse's seminal view, whatever the case in other western democracies and despite its centrality to traditional versions of textbook democracy, the American public is distinctly non-ideological. Our objective is to compare the standard and by far most widely used measure of political ideology-a measure that presumes ideology is one-dimensional-to a more recent measure that allows for a multi-dimensional conception and measurement. This measure demonstrates that while American political elites compete across a single dimension of conflict, the American people organize their policy attitudes around two distinct dimensions, one economic and one social. After explaining how we derived the measure and how it can be used to develop five separate ideological groups, we show how these groups differ politically and why it is not possible to map their preferences onto a one-dimensional measure of ideology.
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  • Any hospice better than none at end of life

    Mohindru, Pooja   Khanna, Rajesh   Bhatia, S. S.  

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  • A user, an interface, or none

    Kartoun   Uri  

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  • Adalimumab for ulcerative colitis: A little is better than none?

    Silvio Danese  

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  • A Club for All and None.

    Lileks   James  

    The author offers opinions on clubs and social groups. The decision of a mothers' group in San Francisco, California to forbid gay men parents from joining and the decision of a private club in New York City to cut its affiliation with a similar club in Great Britain which does not admit women as members are used to support the author's contention that issues of sexual discrimination are often dealt with hypocritically.
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  • Vaccinations While On Thiopurines: Some Protection Is Better Than None

    Melmed   Gil Y  

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