[Biological processes of the human environment regeneration within the Martian crew life support systems]. / Biologicheskie protsessy regeneratsii sredy obitaniia v sisteme zhizneobespecheniia ékipazha marsianskoi ékspeditsii.

Five ground-based experiments at RF SRC-IBMP had the purpose to make a thorough investigation of a model of the human-unicellular algae-mineralization life support system. The system measured 15 m3 and contained 45 liters of alga suspension; the dry alga density was 10 to 12 g/l and water volume (including the alga suspension) amounted to 59 l. More sophisticated LSS models where algae were substituted by higher plants (crop area in the greenhouse equaled 15 m2) were investigated in three experiments from 1.5 mos. to 2 mos. in duration. It was found that the alga containing LSS was able to fulfill not only the macrofunction (air and water regeneration) but also several additional functions (air purification, establishment of microbial cenosis etc.) providing an adequate human environment. This polyfunctionality of the biological regenerative processes is a weighty argument for their integration into space LSSs. Another important aspect is that the unicellular algae containing systems are highly reliable owing to a huge number of species-cells which will be quickly recovered in case of the death of a part of the population and, consequently, functionality of the LSS autotrophic component will be restored before long. For an extended period of time the Martian crew will have no communication with the Earth's biosphere which implies that LSS should be absolutely reliable and redundant. Redundancy can be achieved through installation aboard the vehicle of two systems constructed on different principles of regeneration, i.e. physical-chemical and biological. Each of the LSSs should have the power to satisfy all needs of the crew. The best option is when two systems are functioning in parallel sharing the responsibility for the human environment. Redundancy in this case will mean that in the event of failure or a drastic decrease in performance of one system the other one will make up for the loss by increasing its share in the overall regeneration process.

[Biological life support systems: investigations on board of orbital complex "Mir"]. / Biologicheskie sistemy zhizneobespecheniia: issledovaniia na bortu orbital'nogo kompleksa "Mir".

From 1989 till 1998 twelve experiments were performed by Bulgarian, Russian, Slovak, and US researchers and engineers on the effects of space flight on the model of ecosystem "algae-fishes-bacteria", and ontogenesis of birds (Japanese quail) and higher plants. For the first time several viable chicks were hatched and passed the whole cycle of their embryonic development in the MIR microgravity. The length of the plant ontogenetic cycle as a whole and its specific stages appeared to be same as on Earth. Seeds of Brassica rapa gathered and planted in greenhouse Svet on board MIR yielded robust shoots. Photosynthesis and dark respiration of plants growing in spaceflight were successfully measured.

[Hybrid biophysical-chemical life support systems for human]. / Kompleksnye biologo-fiziko-khimicheskie sistemy zhizneobespecheniia cheloveka.

Based on comparison of biological and physical/chemical regenerative life support systems (LSS) the authors maintain that hybrid LSS will apparently be the most congruous for future space vehicles. In their opinion, a hybrid LSS will evolve from a basic LSS with maximum regenerative functions. One of the precursory experimentally tested LSS could serve as the basic model. This basic LSS may and must incorporate physical/chemical technologies which, without affecting the chemical nature of substances within the system, will subserve synchronization of synthesis and destruction processes underlying the turnover in any ecosystem. Therein lies the advantage of hybrid LSS over modelling of natural ecosystems in which physical and chemical cycles of substance transformation take much longer time than the biological ones.

[The embryonic development of birds in weightlessness]. / Embrional'noe razvitie ptits v usloviiakh nevesomosti.

During the period from March 4 through 24, 1990 an egg-to-egg cycle of quail incubation on the orbital station Mir was completed. Out of 35 eggs, that developed in space, 8 normal hatchlings emerged, 6 of which were able to get out of the egg-shell without any help. Subsequent observations showed that the hatchlings could not get adapted to the weightless environment or know to remain fixed to the wired floor, due to which they were unable to peck.

[Habitability and biological life support systems for man]. / Obitaemost' i biologicheskie sistemy zhizneobespecheniia cheloveka.

This paper discusses general concepts and specific details of the habitability of space stations and planetary bases completely isolated from the Earth for long periods of time. It emphasizes inadequacy of the present-day knowledge about natural conditions that provide a biologically acceptable environment on the Earth as well as lack of information about life support systems as a source of consumables (oxygen, water, food) and a tool for waste management. The habitability of advanced space vehicles is closely related to closed bioregenerative systems used as life support systems.

[Biological life support systems for man]. / Biologicheskie sistemy zhizneobespecheniia cheloveka.

This paper discusses theoretical foundations of biological life support systems (BLSS), major stages of their development and performance parameters of BLSS models developed by the Institute of Biomedical Problems during the past 25 years. Comparison of the size and structure of these models with the structure of natural ecosystems allows the conclusion that BLSS can be operational in an environment that does not differ drastically from natural biocenoses in terms of living matter and basic ingredients, i.e. oxygen, carbon dioxide, water.

[Conversion of plant waste on a solid substrate for a biological life support system of humans]. / Pererabotka rastitel'nykh otkhodov na tverdom substrate dlia biologicheskoi sistemy zhizneobespecheniia cheloveka.

The level of waste processing and utilization of the resultant products in a biological life support system largely determines the degree of system closure. Straw degradation in the humus and an inert substrate was studied when straw was introduced once a month during 3 years. Following 5-6 cycles of straw degradation in the humus, there developed a stable soil biocomplex that functioned as a self-regulation system. After adaptation and completion of the soil biocomplex formation straw degradation in the humus developed at a rate that provided its complete degradation within a certain green-house area.

[Physiological and ecological characteristics of Azolla pinnata and its possible use in biological life support systems]. / Fiziologo-ékologicheskie kharakteristiki vodnogo paporotnika Azolla pinnata i perspektivnost' ego ispol'zovaniia v biologicheskikh sistemakh zhizneobespecheniia (BSZhO) cheloveka.

The principal physiological and ecological characteristics of Azolla pinnata were investigated in order to determine its potential use in biological life support systems. Plant requirements for biogenic elements were specified in order to develop balanced nutrient mixtures for continuous cultivation. Data on the growth and development, photosynthetic and nitrogen fixation rate, and biochemical composition of the plant were obtained for optimal cultivation conditions. The plant biomass contains large quantities of carotenoids and sulfur-containing amino acids, which are deficient in unicellular algae. This makes Azolla an attractive source of the above compounds for biological life support systems and other applications.

[Analysis of the trace contaminants in the atmosphere formed by the life-support environment of the closed system of man-higher plants-lower plants-microorganisms]. / Analiz mikroprimesei v atmosfere, formiruemoi sredoi obitaniia zamknutoi sistemy chelovek-vysshie rasteniia-nizshie rasteniia-mikroorganizmy.

Trace contaminants in the air of a biological life support system which was continuously complicated were examined. Air samples were taken by cooled traps and analyzed by gas chromatography. Changes in the air of the biological life support system as a function of its structure were compared using Hamming distance and composition similarity measures. Matrices of the measures were obtained and a graph whose structure corresponded to changes in the biological life support system was constructed. During prolonged experiments trace contaminants remained relatively stable and changed when a mineralization component was attached. It is concluded that the composition and variations in the organic components of the atmosphere can be used as an integral indicator of the function of the biological life support system as a whole.

[Effect of weightlessness on the water fern Azolla]. / Issledovanie vliianiia nevesomosti na vodnyi paporotnik azolla.

An exposure to 6-day weightlessness of the fern Azolla pinnata R. Br. symbiotically related to the nitrogen fixing alga Anabena azollae did not affect the main biological characteristics (growth, development and morphological structure) of both fern plants and algae. The exposure did not influence the growth rate or subsequent Azolla generations on the Earth.

[Long space flights and the human habitat]. / Dlitel'nye kosmicheskie polety i sreda obitaniia cheloveka

The paper discusses the generation of an environment which may adequately meet human requirements that have developed as a result of evolution in the Earth biosphere as applied to long-duration manned space flights. This environment must exert functional effects on physiological systems of the human body which appear to be underloaded in space flight.