Space FlightAstronautsWeightlessnessFlight, AnimalAerospace MedicineWeightlessness SimulationSpace Motion SicknessDecalcification, PathologicWeightlessness CountermeasuresSpace SimulationCosmic RadiationFoods, SpecializedUnited States National Aeronautics and Space AdministrationSpacecraftGravitationDimenhydrinateBed RestRats, WistarBiomedical ResearchBone ResorptionOxygen IsotopesBone and BonesBiomedical EngineeringTime FactorsWing