[Heart rate and energy expenditure during extravehicular activity in different time of day].

The article discusses the comparative heart rate (HR) characteristics associated with day and night extravehicular activities (EVA). HR was commonly higher in the night but not in the daytime. Presumably, the reason is psychological and physiological challenges of the night work on the background of natural performance decrement. These circumstances could lead to elevation of psychic tension and, consequently, increase of heartbeats to a greater extent as compared with daytime EVA. According to the correlation analysis data, the pattern of HR relation to physical loads evaluated by energy expenditure in the daytime was other than at night, i.e. it was positive unlike the nighttime correlation. We cannot exclude it that in the daytime increase in cardiac output (CO) in response to physical work was largely due to increase in HR, whereas it was stroke volume that dominated during night work; at least, it could support CO fully in the periods of low loading.

[Organism as a functional unity of oscillation processes of varying frequency].

The present concept of organism as an oscillating system is discussed in light of the biological rhythms theory. The phenomenon of biological rhythm is viewed as a result of unity and mutual confrontation of the fundamental conflicts in the life process - destruction and creation. Consideration is given to the system-making role of diurnal rhythms keeping the organism functioning as integration. Possible mechanisms of interrelationships of rhythms with different frequencies based on the principles of ascending from simple to complicated, biological amortization, level destabilization, multiple ratios and frequency locking are dealt with. Emphasis is placed on the necessity of conceptualizing the physiological norm as a rhythmic phenomenon.

[Topics of cosmonauts' work and rest management on board the International Space Station].

Intensity of the rest and work cycle (WRC) of the ISS cosmonauts was examined in terms of overplanning, as well as frequency of sleep shifting and incidence of crew overstrain evidenced from the weekly reports of MCC-M medical operators. Level of WRC intensity in the recent ISS missions was compared with the WRC chronicles of early missions made by three crewmembers including one cosmonaut, and subsequent missions by six crewmembers including 2 or 3 cosmonauts. Though weak, a trend toward a WRC reduction in the period of 2010-2011 was achieved through a more realistic task planning for an average cosmonaut.

[Stress effects of 72-hour sleep deprivation].

Stress effects of 3-d (72-hr) continuous vigilance were studied for renal excretion of 17-oxycorticoids (17-KS), electrolytes (potassium and sodium), and liquid. The investigation involved 12 male subjects aged 23 to 36. Baseline parameters displayed diurnal variations with comparatively high day and comparatively low night values. During the 72-hr vigilance, significant and consistent (statistically fiducial) intensification of 17-KS and potassium excretion occurred in the night-time, i.e., in the period of naturally low values, but only in the first two sleepless nights. As for sodium and liquid excretion, stress-related reduction in these parameters was more consistent and distinct in the day-time, i.e., in the period of naturally high values, rather than in the nighttime. Therefore, the two factors that should be accounted for by investigators of continuous vigilance (and, maybe, other stresses) are the anticipated direction of a stress-reaction and baseline diurnal variation of parameters under study. If stress is expected to increase a parameter, measurements should be done when the parameter is naturally low and, vice versa, if stress is known to reduce a parameter, then measurement should be planned in the period when it is naturally high. If direction of stress-related changes is predictable, investigations can be performed on a twenty-four hour basis.

[Dynamics of operator's efficiency under the condition of long continuous vigil].

Chambered male test-subjects (n = 8) kept awake over 72 hours. Every one or two hours during the initial 67 hours they did a tracking test that took 10 to 15 minutes. The test required intense tracking of rhythmic light spots with unpredictably varying frequency and pressing the button as the frequency changed. Time of latent reaction was determined. The variable was shown to extend with the confinement and fluctuate with the period of approx. 28 hours. Average values on the first sleepless night was longer than the ones on the previous day in all subjects with personal difference ranging from 7 to 37% and averaging 21%. That is, on the first night everyone was less efficient as compared with the previous day which could be excused by fatigue and natural variations in mental efficiency known to rise in the day and reduce in the night hours.

[The present-day issues of ecology, and possible solutions].

Ecology is considered an interdisciplinary bank of knowledge about the relations of humans with nature and anthropogenic environment. The central issue of ecology is prevention of the global catastrophe in consequence of anthropogenic factors. The dire threat of the ecological catastrophe comes from breaching the principle of co-evolution of mankind and nature due to the unilateral prevalence of human interests during formation of the civilization. Issues revealed by the analysis of the present-day knowledge of ecology can be resolved by creating an ecology-oriented ethic system (moral imperative or ecology-focused morals) an ecological imperative (internationally endorsed bans), and taking actions toward the recovery of ruined and preservation of survived eco-systems. Of special concern is analysis of the doctrine of noosphere developed by V.I. Vernadsky. The authors also dwell upon eco-monitoring and prediction with account of the rhythm of animate nature and abiocoen.

[The bio-rhythmic problems of a space flight]. / Bioritmologicheskie problemy kosmicheskogo poleta.

The influence of space-flight factors on the organism's circadian periodicity is discussed. It is shown that in mechanisms of such influence, the transformation of natural structure of Zeitgebers accompanying a space flight, can play the essential role. It is confirmed by the results of ground research carried out in conditions of isolation simulating the usual space flight transformation of Zeitgebers system. The data obtained in the ground researches with isolation, testify that the changes of circadian rhythms in these conditions are similar to those in space flights and frequently are interpreted as the result of influence of weightlessness. Special attention is paid to phenomenon of delay of the daily maximum and to possible connection of this phenomenon with the tendency to transition of rhythmic process in a free-running regime.

[Studies of A L. Chizhevskii: Milestones in space biology and biorhythmology]. / Issledovaniia A. L. Chizhevskogo: veki kosmicheskoi biologii i bioritmologii.

The authors review the experimental and theoretical studies of eminent Russian scholar A.L. Chizhevsky, and his fruitful collaboration with K.E. Tsiolkovsky, a pioneer of the science of rocket navigation. Highlighted are postulates of the modern space biorhythmology furthering the notions of A.L. Chizhevsky about the harmony in nature, and significance of rhythmic phenomena for living organisms.

[The national history space chronobiology]. / Otechestvennye istoki kosmicheskoi bioritmologii.

Analyzed were theories stated in the treatises of Russian researchers V.I. Nikolsky, N.Ya. Perna and A.L. Chizhevsky dedicated to the place of the phenomenon of rhythm in biology and medicine. The authors underline the inceptive role of the fundamental ideas of these scientists in formation and development of space biorhythmology in this country. Presented are main postulates in the area of space biorhythmology formulated in the period of fulfillment of the Russian piloted space programmes.

[Biological rhythm as a reflection of the unity of creation and destruction (life and death)]. / Biologicheskii ritm kak otrazhenie edinstva sozidaniia i razrusheniia (zhizni i smerti).

The paper deals with the analysis of fundamental aspects of nature of the biological rhythm, antinomies incident to this phenomenon, its relation to the phenomena of life and death. The biological rhythm is viewed as an exemplification of the singleness of two qualitatively different states--destruction and creation, dissimilation and assimilation. Since destruction of biological structures in the course of dissimilation is irreversible by character, there is every reason to equal it with death, and to consider life the counter process of assimilative synthesis (creation) of chemical compounds directed toward revival of living substance. From this standpoint, the day phase of the circadian rhythm marked by dominance of destructive processes is a kind of death, whereas the night phase characterized by prevalence of the recovery processes signifies life. That is why the daytime status of organism differs from that at night, which is directly related to diagnostics of internal diseases: in the daytime and at night the same patient seems to be two different persons. Therefore, investigating him not only in the daytime but also at night, we could get more intimate understanding of his diseases, that is make an exhaustive diagnosis. Efficiency of night investigations combined with daytime ones has been confirmed by clinical investigations.

[Sub-circadian rhythms as an instrument for the determination of and prediction for the state of the organism]. / Subtsirkadiannye ritmy kak instrument otsenki i prognozirovaniia sostoianiia organizma.

The paper deals with the analysis of literature concerning the role and hierarchy of circadian rhythms in the structure of rhythmic processes in organism. Substantiation is given to the concept according to which the diagnostic and prognostic value of subcircadian rhythms is predetermined by their wide representation at different levels of the living system organization, high sensitivity to external impacts, and responsiveness to all sorts of shifts in the state of organism. The above considerations are used in the physiology of labor, experimental and clinical medicine. Illustration can be determination of and prediction for the state of patients and subjects exposed to head-down bedrest, g-loads and other debilitating factors based on investigations of subcircadian rhythms. The author presents his own data on determination of and prediction for individual tolerance for passive standing test with account of subcircadian rhythms. Special emphasis is placed on the data about subcircadian rhythms of animals during spaceflight.

[Features of external respiration and pulmonary hyperemia in man during immersion]. / Osobennosti vneshnego dykhaniia i legochnaia giperemiia u cheloveka pri immersionnykh vozdeistviiakh.

Reactions of external respiration on catheterization of main blood vessels were studied in healthy subjects following 12 hr and 5-6 day immersion. The purpose of the investigation was to detect respiratory signs of hyperemia in pulmonary circulation under these conditions. Results of the investigation were compared with the data of great vessel catheterization in patients of a cardiological clinic afflicted with cardiac diseases with lung hyperemia and lung tissue hyperhydration. The results obtained failed to confirm suppositions about elevated blood filling of the lung and a possible increase of lung tissue hydration during water immersion. Catheterization of great vessels in patients and healthy subjects in most cases leads to an increase of respiratory minute volume. In patients with cardiac diseases the respiratory minute volume grew with an adequate rise in breathing rate, respiratory volume and gas exchange parameters unaltered; this suggested excessive blood filling of the lung and resulting higher respiratory resistance. After immersion the healthy subjects displayed an utterly different pattern, i.e. the growth of their respiratory minute volume was provided exclusively by the growth of respiratory volume while breathing rate did not change and gas exchange increased. These observations were considered an evidence of hyperemia and hyperhydration of pulmonary tissue.

[Biorhythmologic analysis of the dynamics of indices of pulmonary ventilation during orthostatic manipulations]. / Bioritmologicheskii analiz dinamiki pokazatelei legochnoi ventiliatsii pri ortostaticheskom vozdeistvii.

Pulmonary ventilation parameters (breathing depth, frequency and minute volume, and alveolar ventilation) of 5 healthy male test subjects who performed a 20-minute tilt test were analyzed. During tilt tests the above parameters showed oscillations in a range of about 1 minute. During the first 1-3 minutes of exposure the parameters exhibited an accentuated synchronization of the oscillations and the phenomenon of "general autonomic switch-over" with the negative phase (fall of the parameters under study below the baseline level after an initial increase above the baseline level). From the 4th minute till the 6.5th minute the function of individual components of the pulmonary ventilation system mismatched and the respiration efficacy fell. Thereafter this synchronization of the processes studied returned to the normal. Adequate adaptation of pulmonary ventilation to tilting developed not earlier than during the 13-14th minute.

[Long-term exposure of rats to high concentrations of carbon dioxide]. / Osobennosti dlitel'nogo vozdeistviia vysokikh kontsentratsii uglekislogo gaza na krysu.

The authors studied the isoenzymatic spectrum of lactic dehydrogenase of the myocardium, the frequency of cardiac contractions and ECG during the action of high carbon dioxide concentration, and also the survival of rats depending on the speed of carbon dioxide concentration increase in the atmosphere. Functional changes noted in the cardiac activity during the carbon dioxide action (concentration 30%, 7 1/2 hours) were not accompanied by any disturbances of carbohydrate metabolism in the myocardium. The most important condition for the survival of rats subjected to the action of high carbon dioxide concentration (up to 50% in the atmosphere) was the speed of elevation of this concentration.