Characterization of the aerosol vertical distributions and their impacts on warm clouds based on multi-year ARM observations.

Aerosol vertical distribution plays a crucial role in cloud development and thus precipitation since both aerosol indirect and semi-direct effects significantly depend on the relative position of aerosol layer in reference to cloud, but its precise influence on cloud remains unclear. In this study, we integrated multi-year Raman Lidar measurements of aerosol vertical profiles from the U.S.

Phase matrix for light scattering by concentrically stratified spheres: comparison of geometric optics and the "exact" theory.

We have developed a hit-and-miss Monte Carlo geometric ray-tracing program to compute the scattering phase matrix for concentrically stratified spheres. Using typical refractive indices for water and aerosols in the calculations, numerous rainbow features appear in the phase matrix that deviate from the results calculated from homogeneous spheres. In the context of geometric ray tracing, rainbows and glory are identified by means of their ray paths, which provide physical explanation for the features produced by the "exact" Lorenz-Mie theory.

Wild-type AIRE cooperates with p63 in HLA class II expression of medullary thymic stromal cells.

During T cell development in the thymus, autoreactive T cells are deleted through a mechanism that is actively supported by medullary epithelial cells. These epithelial cells possess particular transcription factors including autoimmune regulator (AIRE), which is responsible for regulating expression of self-antigens, as well as p63, a p53-like molecule. Here we present evidence suggesting interaction of AIRE with p63 through a SAND domain and a transactivation domain, respectively.

Remote sensing of three-dimensional cirrus clouds from satellites: application to continuous-wave laser atmospheric transmission and backscattering.

A satellite remote sensing methodology has been developed to retrieve 3D ice water content (IWC) and mean effective ice crystal size of cirrus clouds from satellite data on the basis of a combination of the conventional retrieval of cloud optical depth and particle size in a horizontal plane and a parameterization of the vertical cloud profile involving temperature from sounding and/or analysis. The inferred 3D cloud fields of IWC and mean effective ice crystal size associated with two impressive cirrus clouds that occurred in the vicinity of northern Oklahoma on 18 April 1997 and 9 March 2000, obtained from the Department of Energy's Atmospheric Radiation Measurement Program, have been validated against the ice crystal size distributions that were collected independently from collocated and coincident aircraft optical probe measurements. The 3D cloud results determined from satellite data have been applied to the simulation of cw laser energy propagation, and we show the significance of 3D cloud geometry and inhomogeneity and spherical atmosphere on the transmitted and backscattered laser powers.

Remote sensing of cirrus cloud optical thickness and effective particle size for the National Polar-orbiting Operational Environmental Satellite System Visible/Infrared Imager Radiometer Suite: sensitivity to instrument noise and uncertainties in environmental parameters.

We describe sensitivity studies on the remote sensing of cirrus cloud optical thickness and effective particle size using the National Polar-orbiting Operational Environmental Satellite System Visible/Infrared Imager Radiometer Suite 0.67-, 1.24-, 1.

Laser transmission-backscattering through inhomogeneous cirrus clouds.

We have developed a two-dimensional (2D) model for inhomogeneous cirrus clouds in plane-parallel and spherical geometries for the analysis of the transmission and backscattering of high-energy laser beams. The 2D extinction-coefficient and mean effective ice-crystal size fields for cirrus clouds can be determined from a combination of the remote sensing of cirrus clouds by use of the Advanced Very High Resolution Radiometer on board National Oceanic and Atmospheric Administration satellites and the vertical profiling of ice-crystal size distributions available from limited measurements. We demonstrate that satellite remote sensing of the position and the composition of high cirrus can be incorporated directly in the computer model developed for the transmission and backscattering of high-energy laser beams in realistic atmospheres.