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V S Magedov

Publications and source records attributed to V S Magedov.

9 recordsLinked to original sources
PubMed2000

Bion 11 mission hardware.

The mission hardware provided for Bion 11 shared primate experiments included the launch vehicle, biosatellite, spaceflight operational systems, spacecraft recovery systems, life support systems, bioinstrumentation, and data collection systems. Under the unique Russia/US bilateral contract, the sides worked together to ensure the reliability and quality of hardware supporting the primate experiments. Parameters recorded inflight covered biophysical, biochemical, biopotential, environmental, and system operational status.

Animals↗
PubMed2000

Bion 11 mission: primate experiments.

A summary is provided of the major operations required to conduct the wide range of primate experiments on the Bion 11 mission, which flew for 14 days beginning December 24, 1996. Information is given on preflight preparations, including flight candidate selection and training; attachment and implantation of bioinstrumentation; flight and ground experiment designs; onboard life support and test systems; ground and flight health monitoring; flight monkey selection and transport to the launch site; inflight procedures and data collection; postflight examinations and experiments; and assessment of results.

Adaptation, Physiological↗
PubMedDate not supplied

[Activation of respiratory sinus arrhythmia in monkeys during space flight].

During the first day in space the rhesus monkey, called Vernyi, flown on Cosmos-1667 showed higher values of the daytime, night, and daily respiratory sinus arrhythmia (RSA) when compared to those observed before launch and before or the first day of a simulation study. During orbital flight, the mean daily value of RSA was in the range 13.08-16.00 beats/min. In the simulation study, this parameter increased from 4.68 beats/min during the first day to 15.16 beats/min on the 6th day. The mean RSA values during days 1 through 3 were significantly higher in real than in simulation flight. Analysis of rheopneumograms revealed a correlation between respiration parameters and RSA variations. In space, there was no correlation between RSA and HR, which was reported in the simulation study (r = -0.625). Assuming that RSA is a noninvasive indicator of parasympathetic control over cardiac rhythm, it can be postulated that the primate body adapted to microgravity via activation of parasympathetic mechanisms controlling the heart function.

Animals↗
PubMedDate not supplied

[Characteristics of night sleep of monkeys on the ground and during space flight on "Kosmos-1667"].

The data on the sleep structure of two rhesus monkeys, Vernyi and Gordyi, during their 7-day space flight on Cosmos-1667 and a control study staged a month after recovery are discussed. Sleep structure was changed to the greatest extent the night before launch when additional stress factors were involved. During the first night in space Vernyi showed the so-called recoil effect. Later his sleep structure became stabilized: the specific weight of fast sleep diminished and the fast sleep/delta/sleep index in the first two cycles decreased. In the ground-based control study, sleep parameters pointed to a deteriorated health status of the animal: his fast sleep patterns changed and delta-sleep often reached its maximum after a fast sleep episode. In this animal adaptation was associated with fast sleep restructuring. In the second primate, Gordyi, the process of adaptation was extended and took three nights. This animal consistently showed low parameters of delta-sleep during both fright and postflight control study; it exhibited no recoil phenomenon after its reduction in the prelaunch night. The structure of sleep indicated that it played a lesser role in the overall process of adaptation.

Adaptation, Physiological↗
PubMedDate not supplied

[Hemodynamics in monkeys in the initial period of adaptation to weightlessness].

Using pre-implanted electrodes and transducers, arterial pressure and linear blood flow velocity in the common carotid artery of the rhesus-monkey Gordyi were measured during his space flight on a Cosmos biosatellite and ground-based control experiments. As compared to the prelaunch level, blood pressure remained unchanged, blood flow velocity increased significantly and blood flow resistance in the area decreased during the first hours after insertion into orbit. During subsequent flight days mean daily values of blood pressure increased and blood flow returned to the baseline level, although they showed distinct day-night variations. Daily variations of blood flow velocity and its ratio to cardiac output gave evidence that the circulation system of the rhesus-monkey under study rapidly adapted to microgravity conditions.

Adaptation, Physiological↗
PubMedDate not supplied

[Features of changes in blood pressure and blood flow in the common carotid artery of monkeys exposed aboard the biosatellite Cosmos-1514].

Preflight the rhesus-monkey Bion was implanted with sensors and transducers to measure blood pressure and linear flow velocity in the common carotid artery and to compare these parameters with central circulation. At the early flight stage blood pressure increased, blood flow decreased and resistance in the area grew. The last change can be regarded as a compensatory reaction that can provide rapid adaptation of regional circulation to changes in systemic circulation. At later flight stages blood pressure showed distinct circadian oscillations and blood flow, a significant increase when compared to the ground-based 36-hour control study. Regulatory mechanisms of the cardiovascular system changed to the greatest extent on flight day 2. This manifested as a decrease of the amplitude of circadian oscillations of the above circulation parameters. Signs of cardiovascular adaptation to the effects of microgravity were discerned on flight days 3 to 5.

Adaptation, Physiological↗