Manual plasmapheresis in the treatment of Guillain-Barré syndrome.

We report on 41 patients with Guillain-Barré Syndrome (GBS) with disability grade 4 and 5 who were treated with manual plasma exchange (PE). Approximately 20-40 ml/kg body weight of plasma was removed with each manual PE; 63% of patients needed one PE, 24% needed two, 10% needed three, and 2% needed four plasma exchanges. Normal saline, human serum albumin (NSA) and fresh frozen plasma were used in varying proportions as replacement solutions. Ninety-one percent of the patients resumed walking with very little assistance ranging from 4 to 56 days with an average of 25 days from the commencement of the first PE. Manual PE in our series was effective and safe as the reported experience of automated apheresis and less volume of plasma was exchanged in our patients undergoing manual PE when compared to those treated in other studies employing automated PE.

Numerically stable algorithm for discrete-ordinate-method radiative transfer in multiple scattering and emitting layered media.

We summarize an advanced, thoroughly documented, and quite general purpose discrete ordinate algorithm for time-independent transfer calculations in vertically inhomogeneous, nonisothermal, plane-parallel media. Atmospheric applications ranging from the UV to the radar region of the electromagnetic spectrum are possible. The physical processes included are thermal emission, scattering, absorption, and bidirectional reflection and emission at the lower boundary. The medium may be forced at the top boundary by parallel or diffuse radiation and by internal and boundary thermal sources as well. We provide a brief account of the theoretical basis as well as a discussion of the numerical implementation of the theory. The recent advances made by ourselves and our collaborators-advances in both formulation and numerical solution-are all incorporated in the algorithm. Prominent among these advances are the complete conquest of two illconditioning problems which afflicted all previous discrete ordinate implementations: (1) the computation of eigenvalues and eigenvectors and (2) the inversion of the matrix determining the constants of integration. Copies of the FORTRAN program on microcomputer diskettes are available for interested users.

Artificial cloud formation in the atmosphere.

An artificial cloud in the cloudless atmosphere at a temperature below 0 degrees C was formed by introducing pellets of Dry Ice into air containing more water vapor than would be present at the saturation point with respect to ice. Such clouds could be utilized to establish radiative equilibrium between ground and air so as to inhibit the cooling of selective arctic surface regions under clear skies.