Embryogenesis Aboard Shuttle STS-29

Comparison of a space shuttle flight (STS-78) and bed rest on human muscle function.

The purpose of this investigation was to assess muscle fiber size, composition, and in vivo contractile characteristics of the calf muscle of four male crew members during a 17-day spaceflight (SF; Life and Microgravity Sciences Spacelab Shuttle Transport System-78 mission) and eight men during a 17-day bed rest (BR). The protocols and timelines of these two investigations were identical, there...

Further Observations of Space Shuttle Plasma-electrodynamic Effects from Oss-1/sts-3

Recent analyses of ion measurements band electrostatic noise observed in the frequency obtained from the Differential Ion Flux Probe range of 30 Hz to 178 kHz [Shawhan et al., 1984]. (DIFP) on the deployed Plasma Diagnostics Package The Differential Ion Flux Probe (DIFP), used (PDP) during the OSS-1/STS-3 mission have provided for the ion measurements, has been described in an additional insigh...

All Aboard

Space shuttle flight (STS-90) enhances degradation of rat myosin heavy chain in association with activation of ubiquitin-proteasome pathway.

To elucidate the mechanisms of microgravity-induced muscle atrophy, we focused on fast-type myosin heavy chain (MHC) degradation and expression of proteases in atrophied gastrocnemius muscles of neonatal rats exposed to 16-d spaceflight (STS-90). The spaceflight stimulated ubiquitination of proteins, including a MHC molecule, and accumulation of MHC degradation fragments in the muscles. Semiqua...

Evidence for tip velocity oscillations in dendritic solidification.

Dendritic growth experiments were conducted in the reduced-convection environment aboard the space shuttle Columbia on STS-87. Spectral analysis was performed on 30-frame/s video data during growths of isothermal dendrites. Results indicate that pivalic acid dendrites exhibit a subtle oscillatory behavior of the axial growth velocity near the tip, with a frequency component that is associated w...