207 research outputs found
Training of the Engineers on a New Specialty “Engineering of Art Handling of Materials”
Materials of the final reports on the joint Soviet-American experiment on the Kosmos-936 biosatellite
Biological experiments onboard the Kosmos-936 investigated the effect of weightlessness on the basic components of cells, the genetic structure and energy apparatus. Genetic studies were made on the Drosophila melanogaster. Experiments were made on higher vegetation and fungi as well. The results indicate that weightlessness cannot be the principal barrier for normal development. An experiment with ectopic osteogenesis in weightlessness was carried out. Measurements were made of cosmic radiation inside and outside the biosatellite
Synthesis of adaptive critical control methods, identification and management
The main problem of dynamic plant control is the variability of the parameters of the control object, and we are talking even about the nature of external disturbances, the lack of information about their statistical or stochastic characteristics. An approach to the development of an adaptive controller based on the recurrent least squares method is proposed
Lake Baikal Ecosystem Faces the Threat of Eutrophication
Recently there have been reports about large accumulations of algae on the beaches of Lake Baikal, the oldest and deepest freshwater body on earth, near major population centers and in areas with large concentrations of tourists and tourism infrastructure. To evaluate the observations indicating the ongoing process of eutrophication of Lake Baikal, a field study in July 2012 in the two largest bays of Lake Baikal, Barguzinsky and Chivyrkuisky, was organized. The study of phytoplankton using the sedimentary method and quantitative records of accumulations of macrophytes in the surf zone was made. In Chivyrkuisky Bay, we found the massive growth of colorless flagellates and cryptomonads as well as the aggregations of Elodea canadensis along the sandy shoreline (up to 26 kg/m2). Barguzinsky Bay registered abundantly cyanobacterial Anabaena species, cryptomonads, and extremely high biomass of Spirogyra species (up to 70 kg/m3). The results show the presence of local but significant eutrophication of investigated bays. To prevent further extensions of this process in unique ecosystem of Lake Baikal, the detailed study and monitoring of the coastal zone, the identification of the sources of eutrophication, and the development of measures to reduce nutrient inputs in the waters are urgently needed
Luminescent upconversion nanoparticles evaluating temperature-induced stress experienced by aquatic organisms due to environmental variations
Growing anthropogenic activities are significantly influencing the environment and especially aquatic ecosystems. Therefore, there is an increasing demand to develop techniques for monitoring and assessing freshwater habitats changes so that interventions can prevent irrevocable damage. We explore an approach for screening the temperature-induced stress experienced by aquatic organisms due to environmental variations. Luminescent spectra of upconversion [Y2O3: Yb, Er] particles embedded within Caridina multidentata shrimps are measured, while ambient temperature gradient is inducing stress conditions. The inverse linear dependence of logarithmic ratio of the luminescence intensity provides an effective means for temperature evaluation inside aquatic species in vivo. The measured luminescence shows high photostability on the background of complete absence of biotissues autofluorescence, as well as no obscuration of the luminescence signal from upconversion particles. Current approach of hybrid sensing has a great potential for monitoring of variations in aquatic ecosystems driven by climate changes and pollution
Case study of ozone anomalies over northern Russia in the 2015/2016 winter: measurements and numerical modelling
Episodes of extremely low ozone columns were observed over the territory of
Russia in the Arctic winter of 2015/2016 and the beginning of spring 2016. We
compare total ozone columns (TOCs) from different remote sensing techniques
(satellite and ground-based observations) with results of numerical modelling
over the territory of the Urals and Siberia for this period. We demonstrate
that the provided monitoring systems (including the new Russian Infrared
Fourier Spectrometer IKFS-2) and modern three-dimensional atmospheric models
can capture the observed TOC anomalies. However, the results of observations
and modelling show differences of up to 20 %–30 % in TOC
measurements. Analysis of the role of chemical and dynamical processes
demonstrates that the observed short-term TOC variability is not a result of
local photochemical loss initiated by heterogeneous halogen activation on
particles of polar stratospheric clouds that formed under low temperatures in
the mid-winter.</p
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Lake surface temperature [in “State of the Climate in 2017”]
Observed lake surface water temperature anomalies
in 2017 are placed in the context of the recent
warming observed in global surface air temperature
by collating long-term in situ lake
surface temperature observations from some of the
world’s best-studied lakes and a satellite-derived
global lake surface water temperature dataset. The
period 1996–2015, 20 years for which satellite-derived
lake temperatures are available, is used as the base
period for all lake temperature anomaly calculations
Estimation of antimicrobial activities and fatty acid composition of actinobacteria isolated from water surface of underground lakes from Badzheyskaya and Okhotnichya caves in Siberia
Extreme and unusual ecosystems such as isolated ancient caves are considered as potential tools for the discovery of novel natural products with biological activities. Actinobacteria that inhabit these unusual ecosystems are examined as a promising source for the development of new drugs. In this study we focused on the preliminary estimation of fatty acid composition and antibacterial properties of culturable actinobacteria isolated from water surface of underground lakes located in Badzheyskaya and Okhotnichya caves in Siberia. Here we present isolation of 17 strains of actinobacteria that belong to the Streptomyces, Nocardia and Nocardiopsis genera. Using assays for antibacterial and antifungal activities, we found that a number of strains belonging to the genus Streptomyces isolated from Badzheyskaya cave demonstrated inhibition activity against bacteria and fungi. It was shown that representatives of the genera Nocardia and Nocardiopsis isolated from Okhotnichya cave did not demonstrate any tested antibiotic properties. However, despite the lack of antimicrobial and fungicidal activity of Nocardia extracts, those strains are specific in terms of their fatty acid spectrum. When assessing fatty acid profile, we found that polyunsaturated fatty acids were quantitatively dominant in extracts of Nocardia sp. and Streptomyces sp. grown in different media. Saturated fatty acids were the second most abundant type in the fatty acid profile. It was due to palmitic acid. Also, a few monounsaturated fatty acids were detected. The obtained materials can become a basis for development of approaches to use bacteria isolated from caves as a biological sources of bioactive compounds to create medical and veterinary drugs
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