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Biomedical subjects

O Quadens

Publications and source records attributed to O Quadens.

4 recordsLinked to original sources

Telehygiene system for preventive chronopharmacology in space.

A remote computerized health care (telehygiene) system for space travel includes monitoring devices and pharmaceuticals aimed at the optimization of health and the environment. Early risk indicators are provided by dynamic characteristics of rhythms of several frequencies describing variation inside the physiologic range. These rhythm characteristics, assessed as one goes, can be updated and compacted as data accumulate by the use of chronobiologic software that resolves anticipated components of lower and lower frequency, thus providing summaries of data at intervals of differing length. At any time, harbingers of risk, including characteristics of circannual rhythms, can be retrieved in an instant. On their basis, early preventive action can be instituted for risk lowering and for delivery of timed treatment when needed. Preventive or curative health care in space and terrestrial spin-offs are the more effective the more of the chronome (time-structure) is resolved.

Aerospace Medicine↗

Quantified EEG in different G situations.

The electrical activity of the brain (EEG) has been recorded during parabolic flights in trained astronauts and non trained volunteers as well. The Fast Fourier analysis of the EEG activity evidenced more asymmetry between the two brain hemispheres in the subjects who suffered from motion sickness than in the others. However, such a FFT classification does not lead to a discrimination between deterministic and stochastic events. Therefore, a first attempt was made to calculate the dimensionality of "chaotic attractors" in the EEG patterns as a function of the different g-epochs of one parabola. Very preliminary results are given here.

Aerospace Medicine↗

[Eye movements in sleep: towards a model].

The study of the REM-process by means of the oculomotor frequencies has shown that it is a stochastic point process. Therefore, the techniques utilized to quantify the time-dependency of this process were used. The structure of occurrence of REM's quantified by transition probability matrixes evidenced a two-state first order semi-Markov process. The oculo-motor configurations of REM-sleep revealed two independent entities, their number and their relative frequencies. This conclusion was used as a working hypothesis for the Spacelab 1 sleep-recording experiment in zero-gravity. The results confirmed the underlying hypothesis.

Adolescent↗

Eye movements during sleep in weightlessness.

The number of eye movements during sleep increased during the first sleep period in zero gravity but returned to normal by the second night. These rapid-eye-movement functions in flight may be the first variations of an oscillatory system. The ratio of the higher and lower eye movement frequencies oscillates within normal-gravity limits.

Eye Movements↗