Dmitriy Alekseev

We don’t have enough information about this author to calculate their statistics. If you think this is an error let us know.
Learn More
In response to simulated space flights cardiovascular and metabolic changes of 86 volunteers, aged 40-49 and 50-56, were similar to those of young people (25-39 years old). In most aged test subjects, the changes produced by 8-day head-down tilt (-8 degrees) and 7-day water immersion were moderate and reversible. This type of variation of the(More)
The paper presents rheographic investigations of regional haemodynamics (brain, lungs, liver and limbs) during antiorthostatic exposures of varying intensity (-15, -30, -45 degrees, times of exposure 20, 40 and 60 min). Our findings show that the pattern and time of the function of compensatory mechanisms preventing excessive vascular compliance [correction(More)
Powerful single-frequency fiber lasers are usually based on the amplification of low-power radiation of a semiconductor laser diode in several fiber cascades. Amplification of laser radiation in active fiber can undergo mode instability (MI) effect [1-4]. It is observed at output powers exceeding certain level called mode instability power threshold (MIPT).(More)
The pathogenesis of diffuse toxic goiter has not yet been fully understood. The literature increasing commonly focusses on the issues related to the processes occurring in the thyroid gland itself: proliferation, apoptosis, and angiogenesis. AIM to investigate clinical and laboratory parameters, as well as the expression of Ki-67, Bcl-2, Bax, Fas-L, CD34,(More)
The cerebral, pulmonary, liver and peripheral circulation was studied simultaneously in 12 test subjects (aged 24--30) rheographically, photoplethysmographically and rheoplethysmographically; arterial pressure was measured by the Korotkoff method. The measurements were carried out during three antiorthostatic tests at --15degrees for 20 min or --30degrees(More)
Influence of both backward reflections and laser radiation of independent source propagating in backward direction of ytterbium fiber amplifier on mode instability was investigated. Dependences of mode instability threshold on both power and wavelength of the backward signal were measured. In order to explain threshold behavior we took into account backward(More)
Cerebral bioelectric activity of 18 healthy test subjects, aged 31-40, was examined during and after their 182-day head-down tilting. The test subjects were divided into a group that performed countermeasures (exercise, muscle stimulation) against hypokinesia-induced disorders and a control group. During the study EEG changes were most pronounced in the(More)
Postflight rheographic examinations carried out at rest and during postural tests showed noticeable changes in the vascular regulation and significant blood redistribution. On the recovery day there were no signs of the intracranical venous congestion to weightlessness. The tone of cerebral vessels, however, increased to prevent the development of cerebral(More)