Voices of Doubt and Trust.Volney Streamer

Faith, Hope and Doubt

Microchimerism and Renal Transplantation: Doubt Still Persists

Background: The Presence of donor leukocytes in recipients of organ allograft has been shown even several years after transplantation. However, it remains unclear whether this donor cell microchimerism plays an effective role in allograft acceptance or is simply a consequence of immunosuppressive conditions in recipients. Objective: To study microchimerism in a group of kidney transplant recipi...

Climatologies of streamer events

Climatologies of streamer events derived from a transport model and a coupled chemistry-climate model V. Eyring, M. Dameris, V. Grewe, I. Langbein, and W. Kouker DLR Institut für Physik der Atmosphäre, Oberpfaffenhofen, D-82234 Wessling, Germany Forschungszentrum Karlsruhe, Institut für Meteorologie und Klimaforschung, 76344 Eggenstein-Leopoldshafen, Germany Received: 17 October 2002 – Accepted...

Diffuse and streamer regions of sprites

[1] The observed altitude stratification in large number of sprite events, exhibiting a sharp transition between the upper diffuse and lower streamer regions, is used in conjunction with a theoretical model to establish correspondence between sprite luminosity and the ambient mesospheric/lower ionospheric conductivity profile. The reported results provide new means for remote sensing of the low...

Propagation and structure of planar streamer fronts

Streamers are a mode of dielectric breakdown of a gas in a strong electric field: A sharp nonlinear ionization wave propagates into a nonionized gas, leaving a nonequilibrium plasma behind. The ionization avalanche in the tip of the wave is due to free electrons being accelerated in the strong field and ionizing the gas by impact. This chain reaction deeper in the wave is suppressed by the gene...