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Biomedical subjects

S I Stepanova

Publications and source records attributed to S I Stepanova.

At least 19 recordsLinked to original sources
PubMed2004

Some aspects of psychophysiological support of crewmember's performance reliability in space flight.

Crewmembers play an important role in ensuring the efficiency of "crew-spacecraft" system. However, despite of the fact that crewmembers are well trained and highly motivated persons, extreme flight factors may influence negatively on their reliability, and lead to human error occurrence. Therefore, working out methods of human error prevention is very significant to increase crewmember's performance reliability. Human error can occur in the operation of systems for a number of reasons. Within the framework of the present investigation, with use the data collected during "Mir" station missions, the significant (p<0.05) positive correlation of crewmembers errors (CE) frequency with their psychophysiological state (PPS), and work and rest schedule (WRS) intensity has been revealed. Differently, the higher WRS intensity, the crewmember's PPS is worse, and CE frequency is higher. This finding has been based on substantiations of the approach to human reliability management. Its essence will consist of the following: reducing WRS intensity, we thus can improve a crewmember's PPS and, accordingly, reduce CE frequency. This approach is discussed in the paper.

Affect↗
PubMed2003

[The national history space chronobiology].

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.

Chronobiology Phenomena↗
PubMed2003

[The bio-rhythmic problems of a space flight].

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.

Adolescent↗
PubMed2003

[A mission to Mars: the prognostic analysis of concurrent psychological problems].

Psychological implications of situations that may take place during a mission to Mars including desynchronosis, fatigue, psychic asthenization, acute mental disorders, interruption of the information flow, unpredicted transformation of the socio-psychological needs, a persistent conflict tension in the crew, errors in manual control of the vehicle, refusal or impossibility to fulfill an operation, difficulties in communication between the crew and ground controllers were analyzed for determination of their causes and consequences, probable starting time, ways and methods of preventing and surmounting each of these situations.

Astronauts↗
PubMed2002

[Biological rhythm as a reflection of the unity of creation and destruction (life and death)].

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.

Circadian Rhythm↗
PubMed2001

[Psychological aspects of training for and implementation of a piloted expedition to Mars].

Reviewed are the modern notions of the main psychological concerns regarding a mission to Mars which are maintenance of mental health, high professional reliability, and successful readaptation of the Martian crew on return to Earth. The unprecedent trail-blazing interplanetary mission distinguished by autonomy, long period, international crew and a broad range of tasks to tend will set particularly difficult requirements to the psychological support system. Among them prioritized are purposeful character building and training of future crew members already in childhood and youth. The primary goal is to bring up personality with anthropocosmic thinking as a professional quality that will eventually determine personal and professional reliability. Within the system of psychological support, the central place should be given to monitoring of crew mental heath and behavior, and preventive an corrective measures. The longer Martian day (24 hr. 36 min.) rises the issue of effective adaptation to this factor. Special simulators will be required aboard the vehicle to help the crew refresh skills in manipulation of the dynamic board systems. The program of psychological support to the Martian crew must be thoroughly tested in model studies (Antarctic field, ground-based experiments, orbital flights, Lunar base).

Adult↗
PubMed1998

[The aspects of psychophysiological analysis of erroneous actions performed by astronauts].

The experience of manned space missions points to the fact that cosmonaut-operator plays an important role in providing the efficiency and reliability of the crew-spacecraft system. However, the spaceflight factors can have a negative effect on working capacity of crewmembers and give rise to their operational errors. The paper deals with the methodical approach to analysis of the interrelationship of errors and psychophysiological state of cosmonauts as well as the ways of its realization. Described are the system of indices used for expert assessment of the psychophysiological state, peculiarities of work-rest schedule, and intra- and intergroup interaction. Potentialities of this approach are evidenced by results of the analysis of data from one of the MIR missions.

Astronauts↗
PubMed1986

[Analysis of the chromosome number in cells by flow cytometry].

A new flow-cytometric method is described that permits analysis of the number of chromosomes of individual cells. Preliminary stained mitotic cells are passed through a specially designed flow chamber in which they are destroyed just before passing through the focused laser beam of the flow cytometer. Signals from chromosomes of the destroyed cells are counted, and the results are represented as a distribution of the number of chromosomes in the cells. The method may be applied for the detection of relatively rare cells with abnormal numbers of chromosomes in biological and clinical research.

Analog-Digital Conversion↗
PubMedDate not supplied

Methodological approach to study of cosmonauts errors and its instrumental support.

The methodological approach to the study of cosmonauts errors is discussed in the paper. Within its framework an error is considered in psychophysiological aspect as consequence of cosmonaut "psychophysiological troubles" caused by combined effect of flight extreme conditions on his/her organism. This approach was used for the investigation of interrelation between cosmonauts errors, their psychophysiological state and work-rest schedule peculiarities. It includes procedures of expert analysis of data received in the course of radio and TV sessions with crew, analysis of timelines as well deviations in "crew-spacecraft" system functioning. These data are accumulated, systematized and processed in data base. Realization of the suggested approach does not require specialized onboard equipment and crew members time expenditure. Some results of inflight data analysis are presented to illustrate its potentials.

Aerospace Medicine↗
PubMedDate not supplied

[Dynamics of temperature rhythm phases in the course of rhythm inversion].

The process of inversion of the diurnal rhythm of the body temperature was studied on two test subjects during an altered work-rest cycle. The temperature changes during individual phases were investigated. With respect to certain phases it is concluded that the rate of rearrangement depended on the relationship between these phases and the level of the physical and mental activity of the body. The inversion of the temperature rhythm induced changes in those phases of the temperature curve in which the temperature should not have changed due to an altered work-rest cycle. When evaluating the completeness of the rearrangement of the diurnal rhythm of the body temperature brought about by an altered work-rest cycle, it is important to pay particular attention to the body temperature in the minimum phase and in the adjacent phases, since the rate of the rearrangement of the temperature rhythm in these phases can be the lowest.

Adult↗
PubMedDate not supplied

[Use of elongated and shortened days in space flights].

On the basis of the experimental findings and the literature data it is concluded that a 24-hour day should be recommended for space missions. It is assumed that in future prolonged or shortened days may be used. This is confirmed by the hypothesis that the information-energy cost of the diurnal cyle is constant.

Body Temperature↗
PubMedDate not supplied

[Biorhythmic selection of cosmonauts].

The paper describes some features of modern and future interplanetary space missions which may influence the stability of the circadian system of the human body. It presents requirements for biorhythmological selection of cosmonauts. The paper discusses the biorhythmological types of humans: biorhythmologically labile, biorhythmologically inert and intermediate. The time schedule specified by the flight program dictates the selection of the cosmonauts of a certain type for the given mission. The paper suggests methods for the biorhythmological selection of cosmonauts: 1) on the basis of adaptation to the concrete type of "space day" in the flight; 2) on the basis of the biorhythmological type; 3) on the basis of the length of the natural circadian period; 4) on the basis of typological features of the nervous system.

Circadian Rhythm↗
PubMedDate not supplied

[Reorganization of human temperature periodicity following life rhythm inversion in isolation].

The diurnal dynamics of body temperature of four male test subjects was studied before and after inversion of their sleep-wakefulness cycle in the anechoic chamber. One test subject showed rearrangement of the temperature rhythm in accordance with the new cycle which was completed by the 11th day of confined life. The other test subjects displayed only a partial adaptation of body temperature to the new sleep-wakefulness cycle during the 34 experiment.

Adult↗
PubMedDate not supplied

[Attempt to upset the circadian rhythm of urine excretion of potassium].

The paper describes an attempt of shaking (i. e. decreasing inertness) the diurnal rhytnm of urine excretion of potassium in two test subjects under the conditions of 72-hour continuous wakefulness. It is concluded that continuous wakefulness exerts no shaking effect on the diurnal periodicity of the function. It is found that the rate of rearrangement of the diurnal rhythm of urine excretion of potassium after inversion of the diurnal cycle was lowest during sleep and immediately after it. It is emphasized that when evaluating the completeness of inversion of the diurnal rhythm of the function it is important to pay attention to the parameters recorded at night and morning hours.

Adult↗
PubMedDate not supplied

[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.

Ecology↗
PubMedDate not supplied

[Stress and microgravity].

There is an opinion that microgravity does not stress organism of mammalians, humans are not excluded, first of all because of the lack of evidence of activation of the cortical and medullary substance in the adrenals. The article brings forward an argument for the stressful nature of microgravity. Guided by the theoretical assumptions and by factual data, the author makes a supposition that microgravity suppresses stress-reactions implemented by the hypothalamo-pituitary-adrenal and sympathoadrenal systems, for the reason that these reactions have same catabolic features as the specific effects of microgravity. In other words, we should not wave off the idea that to prevent muscular atrophy in microgravity, organism triggers mechanisms of blocking the classic paths of the non-specific stress-reaction involving the glucocorticoid and catecholamine functions of the adrenals. From this standpoint, microgravity modifies markedly the overall pattern of stress reaction, which does not overthrow the concept about the non-specific character of stress and microgravity as a stress-factor.

Adaptation, Physiological↗