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[1] We compare sprite streamer modeling results with high-speed video recordings of sprites made with 50-ms temporal resolution. Both the modeling results and the sprite videos show that sprite streamers propagate with acceleration and expansion during the initial stage of sprite development. The acceleration computed from the modeling for the applied(More)
In Japanese, Koreans and Caucasians, narcolepsy/hypocretin deficiency is tightly associated with the DRB1*15:01-DQA1*01:02-DQB1*06:02 haplotype. Studies in African-Americans suggest a primary effect of DQB1*06:02, but this observation has been difficult to confirm in other populations because of high linkage disequilibrium between DRB1*15:01/3 and(More)
[1] Terrestrial gamma-ray flashes (TGFs) are bright, sub-millisecond bursts of gamma-rays, originating within the Earth's atmosphere. Most TGFs have been detected by spacecraft in low-Earth orbit. Only two TGFs have previously been observed from within our atmosphere: one at ground level and one from an aircraft at 14.1 km. We report on a new TGF-like(More)
The purpose of this study was threefold: to determine (a) the test-retest reliability of the 20-m shuttle test (20 MST) (number of laps), (b) the concurrent validity of the 20 MST (number of laps), and (c) the validity of the prediction equation for VO2max developed by Léger, Mercier, Gadoury, and Lambert (1988) on Canadian children for use with American(More)
  • A Bourdon, V P Pasko, N Y Liu, S Célestin, P Ségur, E Marode
  • 2007
This paper presents formulation of computationally efficient models of photoionization produced by non-thermal gas discharges in air based on three-group Eddington and improved Eddington (SP 3) approximations to the radiative transfer equation, and on effective representation of the classic integral model for photoionization in air developed by Zheleznyak(More)
Modelling studies are presented of positive streamers developing at various pressures in air in a point-to-plane discharge geometry. The modelling results emphasize that the quenching of the singlet excited states of molecular nitrogen emitting photoionizing radiation is responsible for non-similar behaviour of streamers at pressures higher than(More)
  • E S Cramer, J R Dwyer, S Arabshahi, I B Vodopiyanov, N Liu, H K Rassoul
  • 2014
Key Points: • New theoretical investigation into runaway electron physics • Equations can be used to model electron energy spectra • Energy space diffusion maintains an exponential energy spectrum near threshold Abstract Simplified equations describing the transport and energy spectrum of runaway electrons are derived from the basic kinematics of the(More)
[1] This paper reports a modeling study on sprite streamer formation at subbreakdown conditions, i.e., the initiation of sprite streamers in a lightning field below the breakdown threshold field E k. Successful formation of streamers is observed for a variety of electric fields with the lowest field of 0.3E k when an appropriate ionization column is(More)
[1] Modeling results of sprite streamer formation from large ionospheric inhomogeneities or patches (several tens to hundreds of meter wide) indicate that positive streamers can be initiated at subbreakdown conditions from the inhomogeneities with a density comparable to sprite halo densities. For spherical patches with a given radius, the minimum density(More)
[1] This paper reports a modeling study of terrestrial gamma ray flashes (TGFs) produced by relativistic feedback discharges. Terrestrial gamma ray flashes are intense energetic radiation originating from the Earth's atmosphere that has been observed by spacecraft. They are produced by bremsstrahlung interactions of energetic electrons, known as runaway(More)