11,889 research outputs found

    Salmonella serovar distribution and risk factors associated with persistence of shedding in finishing pigs

    Get PDF
    The objectives of this study were to describe the Salmonella serovar distribution and to identify risk factors associated with serovar persistence in finisher pigs. A longitudinal study was conducted in 18 cohorts of pigs. Fecal culture and serotyping were conducted using standard methods

    On the predictability of ice avalanches

    Get PDF
    The velocity of unstable large ice masses from hanging glaciers increases as a power-law function of time prior to failure. This characteristic acceleration presents a finite-time singularity at the theoretical time of failure and can be used to forecast the time of glacier collapse. However, the non-linearity of the power-law function makes the prediction difficult. The effects of the non-linearity on the predictability of a failure are analyzed using a non-linear regression method. Predictability strongly depends on the time window when the measurements are performed. Log-periodic oscillations have been observed to be superimposed on the motion of large unstable ice masses. The value of their amplitude, frequency and phase are observed to be spatially homogeneous over the whole unstable ice mass. Inclusion of a respective term in the function describing the acceleration of unstable ice masses greatly increases the accuracy of the prediction

    Peology and Geochemistry of New Paired Martian Meteorites 12095 and LAR 12240

    Get PDF
    The meteorites LAR 12095 and LAR 12240 are believed to be paired Martian meteorites and were discovered during the Antarctic Search for Meteorites (ANSMET) 2012-2013 Season at Larkman Nunatak. The purpose of this study is to characterize these olivine-phyric shergottites by analyzing all mineral phases for major, minor and trace elements and examining their textural relationships. The goal is to constrain their crystallization history and place these shergottites among other Martian meteorites in order to better understand Martian geological history

    Measuring the cosmic ray acceleration efficiency of a supernova remnant

    Get PDF
    Cosmic rays are the most energetic particles arriving at earth. Although most of them are thought to be accelerated by supernova remnants, the details of the acceleration process and its efficiency are not well determined. Here we show that the pressure induced by cosmic rays exceeds the thermal pressure behind the northeast shock of the supernova remnant RCW 86, where the X-ray emission is dominated by synchrotron radiation from ultra-relativistic electrons. We determined the cosmic-ray content from the thermal Doppler broadening measured with optical spectroscopy, combined with a proper-motion study in X- rays. The measured post-shock proton temperature in combination with the shock velocity does not agree with standard shock heating, implying that >50% of the post-shock pressure is produced by cosmic rays.Comment: Published in Science express, 10 pages, 5 figures and 2 table

    Quantum key distribution using non-classical photon number correlations in macroscopic light pulses

    Get PDF
    We propose a new scheme for quantum key distribution using macroscopic non-classical pulses of light having of the order 10^6 photons per pulse. Sub-shot-noise quantum correlation between the two polarization modes in a pulse gives the necessary sensitivity to eavesdropping that ensures the security of the protocol. We consider pulses of two-mode squeezed light generated by a type-II seeded parametric amplification process. We analyze the security of the system in terms of the effect of an eavesdropper on the bit error rates for the legitimate parties in the key distribution system. We also consider the effects of imperfect detectors and lossy channels on the security of the scheme.Comment: Modifications:added new eavesdropping attack, added more references Submitted to Physical Review A [email protected]

    I Am Distinctive When I Belong: Meeting the Need for Optimal Distinctiveness through Team Identification

    Get PDF
    The development of stronger team identity has previously been explained through the social identity aspect of belonging. Although this has contributed much to our understanding of sport fans, it has neglected an alternative explanation for team identity, specifically the search for distinctiveness. How then do fans develop stronger team identity by \u27standing out\u27 as opposed to \u27fitting in\u27? This paper provides evidence of seven identity management strategies used by fans with a strong psychological connection to their chosen team. Saturation sampling was employed to interview 29 South African rugby union fans via semi-structured interviews, followed by a directed approach to content analysis. The results contribute a stronger explanation of how the psychological need for optimal distinctiveness functions within the attachment process towards stronger fan loyalty, and provides a more complete explanation for the way in which fans can \u27stand out\u27 while still belonging
    corecore