How advances in low-g plumbing enable space exploration.

In many ways, plumbing is essential to life support. In fact, the advance of humankind on Earth is directly linked to the advance of clean, healthy, reliable plumbing solutions. Shouldn't this also be true for the advancement of humankind in space? Unfortunately, the reliability of even the simplest plumbing element aboard spacecraft is rarely that of its terrestrial counterpart. This state of affairs is due entirely to the near-weightless "low-g" state of orbiting and coast spacecraft. But the combined passive capillary effects of surface tension, wetting, and system geometry in space can be exploited to replace the passive role of gravity on earth, and thus achieve similar outcomes there. In this paper, we review a selection of experiments conducted in low-g environments (i.e., ISS and drop towers) that focus on capillary fluidic phenomena. The results of each experiment are highly applicable to subsequent advances in spacecraft plumbing. With examples ranging from spurious droplet ejections to passive bubble coalescence, to droplet bouncing, to complex container wicking, we show how simple low-g demonstrations can lead to significant reliability improvements in practical passive plumbing processes from pipetting to liquid-gas separations, to wastewater transport, to drinking in space.

Peripheral neuropathy following high-dose etoposide and autologous bone marrow transplantation.

We investigated the incidence of peripheral neuropathy in 142 consecutive patients receiving high-dose etoposide between August 1988 and December 1991. A retrospective chart review was conducted. Six patients with hematologic malignancies presented with a new sensory polyneuropathy after receiving an intensive therapy regimen consisting of etoposide 60 mg/kg i.v. and melphalan 140-160 mg/m2 i.v. followed by autologous bone marrow transplantation. Neurologic symptoms began 2-8 weeks after transplant, were grade 2-3 in severity and pursued a chronic course with slow improvement over months. Electromyographic studies in three of the patients tested confirmed distal sensory polyneuropathy. All 6 patients had previously received vincristine 1-60 months prior to autotransplant. We conclude that peripheral neuropathy of moderate severity is a potential complication of high-dose etoposide therapy but appears to be self-limited.