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Neil Armstrong's understated words, "That's one small step for man, one giant leap for mankind." were spoken from Tranquility Base forty years ago. Even today, those words resonate in the ears of millions, including many who had yet to be born when man first landed on the surface of the moon. By their very nature, and in the tnie spirit of exploration, extravehicular activities (EVAs) have generated much excitement throughout the history of manned spaceflight. From Ed White's first space walk in June of 1965, to the first steps on the moon in 1969, to the expected completion of the International Space Station (ISS), the ability to exist, live and work in the vacuum of space has stood as a beacon of what is possible. It was NASA's first spacewalk that taught engineers on the ground the valuable lesson that successful spacewalking requires a unique set of learned skills. That lesson sparked extensive efforts to develop and define the training requirements necessary to ensure success. As focus shifted from orbital activities to lunar surface activities, the required skill-set and subsequently the training methods, changed. The requirements duly changed again when NASA left the moon for the last time in 1972 and have continued to evolve through the Skylab, Space Shuttle ; and ISS eras. Yet because the visits to the moon were so long ago, NASA's expertise in the realm of extra-terrestrial EVAs has diminished. As manned spaceflight again shifts its focus beyond low earth orbit, EVA success will depend on the ability to synergize the knowrled^e gained over 40+ years of spacewalking to create a training method that allowrs a single erewmember toyperfonn equally well, whether perfonnina an EVA on the surface of the Moon, while in the vacuum of space, or heading for a rendezvous with Mars. This paper reviews NASA's past and present EVA training methods and extrapolates techniques from both to construct the basis for future EVA astronaut training..

The present study introduces a new experimental model of hypoxia/reperfusion injury using a newly developed bioreactor system. The injury is introduced and kept localized via fluid dynamic manipulation. Using low Reynolds number fluid flow, regions of the culture can be injured while maintaining physiological conditions in the remaining culture. This approach enables both normal and injured cells within the same monolayer to be investigated side-by-side. The current study evaluated the ability of the model to induce localized reperfusion injury in a monolayer of fetal canine cardiomyocytes (FCCs). Significant apoptosis was found in the hypoxia/reperfusion-injured but not normal-flow regions of the myocyte cultures. The model holds the potential to help elucidate the fundamental mechanisms of hypoxic/reperfusion insults in myocardium.