Deployment/retraction mechanism for solar maximum mission high gain antenna system

A mechanism called a deployment/retraction assembly (DRA) which provides not only a stable, but a deployable platform for the high gain antenna system (HGAS) aboard the Solar Maximum Mission (SMM) spacecraft is described. The DRA also has the capability to retract the system upon command

Fabrication of carbon film composites for high-strength structures

Physical and mechanical properties of fiber composite materials consisting of carbon films are described. Application of carbon film structural composites for constructing microwave filters or optical instruments is proposed. Applications in aerospace and architectural structures for high strength and low density properties are discussed

Physical properties of thin films

Studies and experiments are presented on carbon, boron, aluminum oxide, zirconium silicate, aluminum, and titanium vapor-deposited on polyimide film substrates

Large diameter astromast development, phase 1

Coilable-longeron lattice columns called Astromasts (trademark) were manufactured for a variety of spacecraft missions. These flight structures varied in diameter from 0.2 to 0.5 meter (9 to 19 in.), and the longest Astromast of this type deploys to a length of 30 meters (100 feet). A double-laced diagonal Astromast design referred to as the Supermast (trademark) which, because it has shorter baylengths than an Astromast, is approximately four times as strong. The longeron cross section and composite material selection for these structures are limited by the maximum strain associated with stowage and deployment. As a result, future requirements for deployable columns with high stiffness and strength require the development of both structures in larger diameters. The design, development, and manufacture of a 6.1-m-long (20-ft), 0.75-m-diameter (30-in.), double-laced diagonal version of the Astromast is described

Axisymmetric and cylindrical isostable structures - A concept

Mathematical formulation, suitable for analytical design of structural networks with uniform local stability, yields idealized solutions for specific two-family networks

Axisymmetric and cylindrical isostabiloids

Differential equations for compression loaded axisymmetric cylindrical structure

Experience with daptomycin daily dosing in ICU patients undergoing continuous renal replacement therapy

Purpose: For critically ill patients undergoing continuous renal replacement therapy (CRRT), daptomycin dosing recommendations are scarce. We, therefore, retrospectively assessed routinely measured daptomycin plasma concentrations, daptomycin dose administered and microbiological data in 11 critically ill patients with Gram-positive infections that had received daptomycin once daily. Methods: The retrospective analysis included critically ill patients treated at the intensive care unit (ICU) who had daptomycin plasma concentrations measured. Results: Daptomycin dose ranged from 3 to 8mg/kg/q24h in patients undergoing CRRT (n=7) and 6 to 10mg/kg/q24h in patients without CRRT (n=4). Peak and trough concentrations showed a high intra- and inter-patient variability in both groups, independent of the dosage per kg body weight. No drug accumulation was detected in CRRT patients with once-daily daptomycin dosing. Causative pathogens were Enterococcus faecium (n=6), coagulase-negative Staphylococcus (n=2), Staphylococcus aureus (n=2) and unknown in one patient. Microbiological eradication was successful in 8 of 11 patients. Two of three patients with unsuccessful microbiological eradication and fatal outcome had an Enterococcus faecium infection. Conclusion: In critically ill patients undergoing CRRT, daptomycin exposure with once-daily dosing was similar to ICU patients with normal renal function, but lower compared to healthy volunteers. Our data suggest that daptomycin once-daily dosing is appropriate in patients undergoing CRR

Axisymmetric filamentary structures

Axisymmetric filamentary structure