Tibial and gastrocnemian vein response to LBNP after a 60 day bedrest with and without counter-measures (WISE study).

Unlabelled: The objective was to quantify calf vein cross section area (CSA) maximal enlargement and the percent change in response to LBNP (lower body negative pressure) after a 60 day bedrest.

Method: The 24 healthy volunteers (25-40 y) of the WISE 60 day HDT(-6 degree) bedrest, were divided into 3 groups: Control (Co), Exercise countermeasure (Ex: treadmill under LBNP and flywheel), Nutrition (Nut: daily protein supplement). All were studied at -45mmHg LBNP pre and at HDT day 55.

Noncontact measurement of vibration using airborne ultrasound.

A noncontact ultrasonic method for measuring the surface normal vibration of objects was studied. The instrument consists of a pair of 420 kHz ultrasonic air transducers. One is used to emit ultrasounds toward the moving surface, and the other receives the ultrasound reflected from the object under test.

Assessment of the inflight cardiovascular adaptation & deconditioning. (14 day Antarès spaceflight).

Objectives & method: (1) assess the main cardiac and vascular hemodynamic changes induced by the 0.g. (2) evaluate, the astronaut orthostatic tolerance, inflight, using LBNP.

Evaluation of cerebral blood flow in rabbits with transcranial Doppler sonography: first results.

A transcranial Doppler sonographic system with a special 2-MHz probe for prolonged experimentation has been developed for Doppler waveform recordings from the basilar artery on rabbits. Measurements were made from the maximum velocity wave form, and Pourcelot's resistance index was used to express the results. The diastolic flow, similar to that observed in humans in physiological conditions, decreases with increased intracranial pressure during chronic intracranial hypertension.