Teleguided self-ultrasound scanning for longitudinal monitoring of muscle mass during spaceflight.

Loss of muscle mass is a major concern for long duration spaceflight. However, due to the need for specialized equipment, muscle size has only been assessed before and after spaceflight where ~20% loss is observed. Here, we demonstrate the utility of teleguided self-ultrasound scanning (Tele-SUS) to accurately monitor leg muscle size in astronauts during spaceflight. Over an average of 168 ± 57 days of spaceflight, 74 Tele-SUS sessions were performed. There were no significant differences between panoramic ultrasound images obtained by astronauts seven days prior to landing and expert sonographer after flight or between change in muscle size assessed by ultrasound and magnetic resonance imaging. These findings extend the current capabilities of ultrasound imaging to allow self-monitoring of muscle size with remote guidance.

Detection of a dynamic cone-shaped meniscus on the surface of fluids in electric fields.

A cone-shaped meniscus of electrified fluids, often called a Taylor cone, is observed in rain drops and lightning and employed in various physical instruments and experimental techniques, but the way it evolves from a rounded shape to a cone is a long-standing puzzle. Earth's gravity and microgravity measurements on the meniscus whose height is just shy of droplet ejection reveal that field-driven cusp evolution exhibits a universal self-similarity insensitive to the forcing field and scaled by the fluid surface tension and density. Our work paves the way for dynamic control of field-driven phenomena in fluids.

Optic disc edema in an astronaut after repeat long-duration space flight.

BACKGROUND: A number of ophthalmic findings including optic disc edema, globe flattening, and choroidal folds have been observed in several astronauts after long-duration space flights. The authors report the first astronaut with previously documented postflight ophthalmic abnormalities who developed new pathological changes after a repeat long-duration mission. METHODS: A case study of an astronaut with 2 long-duration (6 months) exposures to microgravity. Before and after his first long-duration space flight, he underwent complete eye examination, including fundus photography. Before and after his second flight, 9 years later, he underwent fundus photography, optical coherence tomography, ocular ultrasonography, and brain magnetic resonance imaging, as well as in-flight fundus photography and ultrasound. RESULTS: After his first long-duration mission, the astronaut was documented to have eye findings limited to unilateral choroidal folds and a single cotton wool spot. During a subsequent 6-month mission, he developed more widespread choroidal folds and new onset of optic disc edema in the same eye. CONCLUSION: Microgravity-induced anatomical changes that occurred during the first mission may have set the stage for recurrent or additional changes when the astronaut was subjected to physiological stress of repeat space flight.