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BACKGROUND Remdesivir, a nucleotide analogue prodrug that inhibits viral RNA polymerases, has shown in vitro activity against SARS-CoV-2. METHODS We provided remdesivir on a compassionate-use basis to patients hospitalized with Covid-19, the illness caused by infection with SARS-CoV-2. Patients were those with confirmed SARS-CoV-2 infection who had an oxygen saturation of 94% or less while they were breathing ambient air or who were receiving oxygen support. Patients received a 10-day course of remdesivir, consisting of 200 mg administered intravenously on day 1, followed by 100 mg daily for the remaining 9 days of treatment. This report is based on data from patients who received remdesivir during the period from January 25, 2020, through March 7, 2020, and have clinical data for at least 1 subsequent day. RESULTS Of the 61 patients who received at least one dose of remdesivir, data from 8 could not be analyzed (including 7 patients with no post-treatment data and 1 with a dosing error). Of the 53 patients whose data were analyzed, 22 were in the United States, 22 in Europe or Canada, and 9 in Japan. At baseline, 30 patients (57%) were receiving mechanical ventilation and 4 (8%) were receiving extracorporeal membrane oxygenation. During a median follow-up of 18 days, 36 patients (68%) had an improvement in oxygen-support class, including 17 of 30 patients (57%) receiving mechanical ventilation who were extubated. A total of 25 patients (47%) were discharged, and 7 patients (13%) died; mortality was 18% (6 of 34) among patients receiving invasive ventilation and 5% (1 of 19) among those not receiving invasive ventilation. CONCLUSIONS In this cohort of patients hospitalized for severe Covid-19 who were treated with compassionate-use remdesivir, clinical improvement was observed in 36 of 53 patients (68%). Measurement of efficacy will require ongoing randomized, placebo-controlled trials of remdesivir therapy.

The Monte Carlo Adjoint Shielding Code System, MASH, calculates neutron and gamma-ray environments and radiation protection factors for armored military vehicles, structures, trenches, and other shielding configurations by coupling a forward discrete ordinates air-overground transport calculation with an adjoint Monte Carlo treatment of the shielding geometry. Efficiency and optimum use of computer time are emphasized. The code system includes the GRTUNCL and DORT codes for air-overground transport calculations, the MORSE code with the GIFT5 combinatorial geometry package for adjoint shielding calculations, and several peripheral codes that perform the required data preparations, transformations, and coupling functions. MASH is the successor to the Vehicle Code System (VCS) initially developed at Oak Ridge National Laboratory (ORNL). The discrete ordinates calculation determines the fluence on a coupling surface surrounding the shielding geometry due to an external neutron/gamma-ray source. The Monte Carlo calculation determines the effectiveness of the fluence at that surface in causing a response in a detector within the shielding geometry, i.e., the dose importance of the coupling surface fluence. A coupling code folds the fluence together with the dose importance, giving the desired dose response. The coupling code can determine the dose response as a function of the shielding geometry orientation relative to the source, distance from the source, and energy response of the detector. This user's manual includes a short description of each code, the input required to execute the code along with some helpful input data notes, and a representative sample problem (input data and selected output edits) for each code., Prepared in cooperation with Science Applications International Corp.

This work involves theoretical analyses of turbulence in high speed flow and large eddy simulation results for the mixing layer. Analysis indicates that turbulence is dominated by streamwise vortices as the Mach number approaches infinity. A conceptual model based on swept vortices makes predictions about the sweep angle of these vortices from spanwise at low speeds to streamwise at high speeds, and about the reduced spreading rate at high speeds. Simulations of planar shear layers, started from random initial disturbances, validate these structural predictions. Some interesting characteristics about high speed turbulence have been identified. Shocks are generally rare and weak, even at a convective Mach number of 2.5, because the flow normal to the swept vortices is subcritical. The turbulence kinetic energy is dominated by streamwise fluctuations, while the other energy components are much smaller. The pressure velocity correlations promote weak transfer of energy from the streamwise fluctuations to the other components of energy, and they strongly suppress the shear stress. These statistics are, in general, compatible with the swept vortex structure of turbulence at high Mach number. Compressible turbulence, Flow simulation mathematical models.

An AM-VSB fiber video distribution system combines an erbium-doped fiber power amplifier with a low-noise receiver to attain a 21 dB link budget for 40 channels., This article is from 'OSA Proceedings of the Topical Meeting on Optical Amplifiers and their Applications Held in Snowmass Village, Colorado on 24-26 July 1991. Volume 13,' AD-A252 974, p218 thru p221.

The numerous facets of autoclave moulding have been investigated in order to provide an improved understanding of empirically derived cure cycles. Such features as partial-cure, dwell-time, dual vacuum, and dual pressure have been examined and their significance in relation to laminate quality explained. (Keywords: carbon reinforced composites, carbon fibers, plastics)

The biological effects on the residents of Hiroshima and Nagasaki due to initial irradiation exposure during the nuclear attacks of World War II was recognized immediately as an important source of information. After the war, an extensive effort gathered data concerning the locations of individuals at the time of the attack and their subsequent medical histories. The data from personnel located in reinforced concrete buildings are particularly significant, since large groups of occupants received radiation injury without complications due to blast and thermal effects. In order to correlate the radiation dose with physiological effects, the dose to each individual must be calculated. Enough information about the construction of the buildings was available after the war to allow a radiation transport model to be constructed, but the accurate calculation of penetration into such large, thick walled three-dimensional structures was beyond the scope of computing technology until recently. Now, the availability of Cray vector computers and the development of a specially-constructed discrete ordinates transport code, TORT, have combined to allow the successful completion of such a study. This document describes the radiation transport calculations and tabulates the resulting doses by source component and individual case location. An extensive uncertainty analysis is also included. These data are to be used in another study as input to a formal statistical analysis, resulting in a new value for the LD50 dose, i.e., the dose at which the mortality risk is 50%.