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Каталог книг и продолжающихся изданий библиотеки Института биофизики СО РАН

Иностранные журналы библиотеки Института биофизики СО РАН

Отечественные журналы библиотеки Института биофизики СО РАН

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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Prokopkin I., Makhutova O., Kravchuk E., Sushchik N., Anishchenko O., Gladyshev M.
Заглавие : Assessing the reliability of quantitative fatty acid signature analysis and compound-specific isotope analysis-based mixing models for trophic studies
Место публикации : Biomolecules: MDPI, 2021. - Vol. 11, Is. 11. - Ст.1590. - ISSN 2218273X (ISSN), DOI 10.3390/biom11111590
Аннотация: The study of the trophic relationships of aquatic animals requires correct estimates of their diets. We compared the quantitative fatty acid signature analysis (QFASA) and the isotope?mixing model IsoError, based on the compound?specific isotope analysis of fatty acids (CSIA?FA), which are potentially effective models for quantitative diet estimations. In a 21?day experiment, Daphnia was fed a mixture of two food items, Chlorella and Cryptomonas, which were supplied in nearly equal proportions. The percentages and isotope values of the FAs of the algal species and Daphnia were measured. The IsoError based on CSIA?FA gave an estimation of algae consumption using only one FA, 18:3n?3. According to this model, the proportion of consumption of Chlorella decreased while the proportion of consumption of Cryptomonas increased during the experiment. The QFASA model was used for two FA subsets—the extended?dietary subset, which included sixteen FAs, and the dietary one, which included nine FAs. According to both subsets, the portion of consumed Chlorella decreased from Day 5 to 10 and then increased at Day 21. The comparison of the two model approaches showed that the QFASA model is a more reliable method to determine the contribution of different food sources to the diet of zooplankton than the CSIA?based mixing model. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Lisitsa, Albert E., Sukovatyi, Lev A., Bartsev, Sergey, I, Deeva, Anna A., Kratasyuk, Valentina A., Nemtseva, Elena, V
Заглавие : Mechanisms of Viscous Media Effects on Elementary Steps of Bacterial Bioluminescent Reaction
Колич.характеристики :19 с
Коллективы : Ministry of Science and Higher Education of the Russian Federation [FSRZ-2020-0006]; RFBR, Krasnoyarsk Territory and Krasnoyarsk Regional Fund of Science [20-44-243002]; RFBRRussian Foundation for Basic Research (RFBR) [20-34-90118]
Место публикации : Int. J. Mol. Sci.: MDPI, 2021. - Vol. 22, Is. 16. - Ст.8827. - ISSN 1422-0067(eISSN), DOI 10.3390/ijms22168827
Примечания : Cited References:59. - The research was funded by the Ministry of Science and Higher Education of the Russian Federation (projects No. FSRZ-2020-0006); by RFBR, Krasnoyarsk Territory and Krasnoyarsk Regional Fund of Science (project No. 20-44-243002); by RFBR according to the research project No. 20-34-90118.
Предметные рубрики: FLAVIN INTERMEDIATE
REDUCED FLAVIN
RATE CONSTANTS
LUCIFERASE
Аннотация: Enzymes activity in a cell is determined by many factors, among which viscosity of the microenvironment plays a significant role. Various cosolvents can imitate intracellular conditions in vitro, allowing to reduce a combination of different regulatory effects. The aim of the study was to analyze the media viscosity effects on the rate constants of the separate stages of the bacterial bioluminescent reaction. Non-steady-state reaction kinetics in glycerol and sucrose solutions was measured by stopped-flow technique and analyzed with a mathematical model developed in accordance with the sequence of reaction stages. Molecular dynamics methods were applied to reveal the effects of cosolvents on luciferase structure. We observed both in glycerol and in sucrose media that the stages of luciferase binding with flavin and aldehyde, in contrast to oxygen, are diffusion-limited. Moreover, unlike glycerol, sucrose solutions enhanced the rate of an electronically excited intermediate formation. The MD simulations showed that, in comparison with sucrose, glycerol molecules could penetrate the active-site gorge, but sucrose solutions caused a conformational change of functionally important alpha Glu175 of luciferase. Therefore, both cosolvents induce diffusion limitation of substrates binding. However, in sucrose media, increasing enzyme catalytic constant neutralizes viscosity effects. The activating effect of sucrose can be attributed to its exclusion from the catalytic gorge of luciferase and promotion of the formation of the active site structure favorable for the catalysis.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Fritsler Y., Bartsev S., Belozor O., Ant. S., And. S.
Заглавие : Modifying the Models of Calcium Dynamics in Astrocytes by Ryanodine Release
Место публикации : Math. Biol. Bioinform.: Russian Academy of Sciences,Department of the Earth Sciences, 2021. - Vol. 16, Is. 1. - С. 86-100. - ISSN 19946538 (ISSN), DOI 10.17537/2021.16.86
Аннотация: The influence of ryanodine channels on the cytosole Ca2+dynamics was studied. We added the equations for ryanodine receptors and voltage-gated calcium channels into the original De Pitta et al. model of Ca2+. The derived model was shown to have significantly wider range of predictions: we derived the frequency of cytosole calcium spontaneous oscillations (which are absent in the original De Pitta et al. model) for various existing models of Ca2+signalling in astrocytes. Particularly, the initial De Pitta et al. results can be converted to either Lavrentovich and Hemkin model or in the Dupont et al model predictions. The absence of the Ca2+oscillations in astrocytes with the active ryanodine channels only was recently reported. This behaviour can be achieved in our model predictions for the certain values of parameters, which are supposedly responsible for the bifurcation landscape between the oscillatory and non-oscillatory dynamics of cytosol Ca2+in astrocytes. We also investigated the interplay between the spontaneous and glutamate-triggered oscillations. © 2021. All Rights Reserved.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Lisitsa A. E., Sukovatyi L. A., Bartsev S. I., Deeva A. A., Kratasyuk V. A., Nemtseva E. V.
Заглавие : Mechanisms of viscous media effects on elementary steps of bacterial bioluminescent reaction
Место публикации : Int. J. Mol. Sci.: MDPI AG, 2021. - Vol. 22, Is. 16. - Ст.8827. - ISSN 16616596 (ISSN), DOI 10.3390/ijms22168827
Аннотация: Enzymes activity in a cell is determined by many factors, among which viscosity of the microenvironment plays a significant role. Various cosolvents can imitate intracellular conditions in vitro, allowing to reduce a combination of different regulatory effects. The aim of the study was to analyze the media viscosity effects on the rate constants of the separate stages of the bacterial biolumi-nescent reaction. Non-steady-state reaction kinetics in glycerol and sucrose solutions was measured by stopped-flow technique and analyzed with a mathematical model developed in accordance with the sequence of reaction stages. Molecular dynamics methods were applied to reveal the effects of cosolvents on luciferase structure. We observed both in glycerol and in sucrose media that the stages of luciferase binding with flavin and aldehyde, in contrast to oxygen, are diffusion-limited. More-over, unlike glycerol, sucrose solutions enhanced the rate of an electronically excited intermediate formation. The MD simulations showed that, in comparison with sucrose, glycerol molecules could penetrate the active-site gorge, but sucrose solutions caused a conformational change of functionally important ?Glu175 of luciferase. Therefore, both cosolvents induce diffusion limitation of substrates binding. However, in sucrose media, increasing enzyme catalytic constant neutralizes viscosity effects. The activating effect of sucrose can be attributed to its exclusion from the catalytic gorge of luciferase and promotion of the formation of the active site structure favorable for the catalysis. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
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Вид документа : Статья из сборника (выпуск продолж. издания)
Шифр издания :
Автор(ы) : Kovalev A. A., Ivanova Yu. D., Sukhovolskiy A. A., Volkov V. E., Sukhovolskiy V. G.
Заглавие : Mathematical models for determining the boundaries of forest areas unstable to the appearance of insects using satellite data (MODIS)
Место публикации : IOP Conference Series: Materials Science and Engineering: Institute of Physics Publishing, 2020. - Vol. 734: 2nd International Scientific Conference on Advanced Technologies in Aerospace, Mechanical and Automation Engineering, MIST: Aerospace 2019 (18 November 2019 through 21 November 2019, ) Conference code: 157461, Is. 1. - Ст.012091. - , DOI 10.1088/1757-899X/734/1/012091
Аннотация: The proposed approach allows us to evaluate the response of forest stands to local weather changes and resistance to insect attack without using data from weather stations, sometimes located far from experimental forest areas. All raw data were obtained during the season using remote sensing data (MODIS / AQUA). The ability to pre-determine decrease and loss of forest stands resistance to possible insect attacks can be extremely important for solving the tasks of forest-entomological monitoring and calculating the risk of forest insect's outbreaks. © Published under licence by IOP Publishing Ltd.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Belolipetskii, Victor M., Genova, Svetlana N., Degermendzhy, Andrey G., Zykov, Vladimir V., Rogozin, Denis Yu
Заглавие : One-dimensional Model for Studying Seasonal Changes of Vertical Structure of Salt Lake Uchum
Колич.характеристики :9 с
Коллективы : RFBR [16-05-00091]; Russian Foundation for Basic Research; government of the region of the Russian Federation [18-45-243002]
Место публикации : J. Sib. Fed. Univ.-Math. Phys.: SIBERIAN FEDERAL UNIV, 2019. - Vol. 12, Is. 1. - С. 100-108. - ISSN 1997-1397, DOI 10.17516/1997-1397-2019-12-1-100-108. - ISSN 2313-6022(eISSN)
Примечания : Cited References:19. - The work was supported by the RFBR grants (16-05-00091) and Russian Foundation for Basic Research and the government of the region of the Russian Federation, grant 18-45-243002.
Предметные рубрики: CIRCULATION
Ключевые слова (''Своб.индексиров.''): salt lake--one-dimensioanal vertical model--temperature and salinity--profiles of water
Аннотация: Many salt lakes are meromictic, in which the water column is not mixed to the bottom for at least one year. In the stratified lake, the upper (epilimnion) and deep (hypolimnion) layers are distinguished, in which the density gradients are small. Between them is a layer of water (metalimnion), within which the density gradient is great. In the near-bottom layer, hydrogen sulphide accumulates and there is no oxygen. One-dimensional mathematical models are used to determine the dynamics of the vertical thermohaline structure of the salt lake Uchum. Two periods in the annual regime are considered: the period of the absence of the ice cover (IC) and the period with the existence of the IC. The vertical distributions of temperature and water salinity in Lake Uchum have been calculated in different seasons. The results of the calculations are consistent with the data of field measurements.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bartsev S. I., Pochekutov A. A.
Заглавие : An elementary multistage discrete model of soil organic matter transformations with a continuous scale of stability
Место публикации : Ecol. Model.: Elsevier B.V., 2019. - Vol. 393. - С. 61-65. - ISSN 03043800 (ISSN) , DOI 10.1016/j.ecolmodel.2018.12.012
Ключевые слова (''Своб.индексиров.''): kinetics of soil organic matter transformations--model of soil organic matter transformations--soil organic matter--biogeochemistry--biological materials--decay (organic)--organic compounds--soils--continuous scale--discrete modeling--elementary model--law of mass action--multistage process--realistic model--soil organic matters--transformation process--mathematical transformations--biotransformation--chemical alteration--decomposition--numerical model--reaction kinetics--soil organic matter
Аннотация: The proposed elementary mathematical model of formation and decomposition of soil organic matter (SOM) is based on using equations of chemical kinetics to describe the multistage process of SOM transformation. The model both describes each step of transformation in accordance with the law of mass action and postulates the trend of increasing stability of the matter towards further transformation, which is common for all steps. Analysis of the model demonstrates that it is extremely difficult to construct a realistic model of SOM dynamics by assembling elementary models of the type presented in this study into the full description of SOM transformation processes. © 2018 Elsevier B.V.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shershneva A. M., Murueva A. V., Zhila N. O., Volova T. G.
Заглавие : Antifungal activity of P3HB microparticles containing tebuconazole
Место публикации : J. Environ. Sci. Health Part B Pestic. Food Contamin. Agric. Wastes: Taylor and Francis Inc., 2019. - Article in press. - ISSN 03601234 (ISSN) , DOI 10.1080/03601234.2018.1550299
Ключевые слова (''Своб.индексиров.''): antifungal activity--encapsulation--microparticles--poly-3-hydroxybutyrate--tebuconazole--agricultural chemicals--emulsification--encapsulation--fungicides--anti-fungal activity--average diameter--encapsulation efficiency--fusarium moniliforme--micro-particles--phytopathogenic fungi--poly-3-hydroxybutyrate--tebuconazole--fungi
Аннотация: In this study, tebuconazole (TEB)-loaded poly-3-hydroxybutyrate (P3HB)-based microparticles were developed and comprehensively characterized. TEB-loaded microparticles with the initial loading amounts of the fungicide of 10, 25, and 50% of the polymer mass (TEB 10, TEB 25, and TEB 50%) were prepared using emulsion technique. Encapsulation efficiency of TEB varied from 59 to 86%. As the loading amount was increased, the average diameter of microparticles increased too, from 41.3 to 71.7 µm, while zeta potential was not influenced by TEB loading, varying between –32.6 and –35.7 mV. TEB was gradually released from the microparticles to the model medium, and after 60 d, from 25 to 43% of TEB was released depending on the content of the encapsulated fungicide. The data obtained from in vitro TEB release were fitted to different mathematical models. It was shown that the release profiles of TEB could be best explained by the Zero-order, Higuchi, and Hixson–Crowell models. The antifungal activity of the P3HB/TEB microparticles against phytopathogenic fungi Fusarium moniliforme and Fusarium solani was demonstrated by in vitro tests conducted in Petri dishes. Thus, hydrophobic agrochemicals (TEB) can be effectively encapsulated into P3HB microparticles to construct slow-release formulations. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Dubovskaya, Olga P., Tolomeev, Aleksandr P., Kirillin, Georgiy, Buseva, Zhanna, Tang, Kam W., Gladyshev, Michail I.
Заглавие : Effects of water column processes on the use of sediment traps to measure zooplankton non-predatory mortality: a mathematical and empirical assessment
Колич.характеристики :16 с
Коллективы : German Research Foundation (DFG) [GR-1540/29-1]; Russian Foundation for Basic Research (RFBR) [16-54-12048]; Russian Federal Tasks of Fundamental Research [51.1.1]; RF President Council on Grants for leading RF scientific schools [9249.2016.5]
Место публикации : J. Plankton Res.: OXFORD UNIV PRESS, 2018. - Vol. 40, Is. 1. - С. 91-106. - ISSN 0142-7873, DOI 10.1093/plankt/fbx066. - ISSN 1464-3774(eISSN)
Примечания : Cited References:49. - This work was a part of the joint German-Russian Project "Mortality of Zooplankton in lake ecosystems and its potential contribution to carbon mineralization in pelagic zone" supported by the German Research Foundation (DFG no. GR-1540/29-1) and the Russian Foundation for Basic Research (RFBR no. 16-54-12048). The work also was partly supported by Russian Federal Tasks of Fundamental Research (project no. 51.1.1) and by grant (no. 9249.2016.5) from the RF President Council on Grants for leading RF scientific schools.
Предметные рубрики: NONCONSUMPTIVE MORTALITY
CRUSTACEAN ZOOPLANKTON
VERTICAL-DISTRIBUTION
Ключевые слова (''Своб.индексиров.''): zooplankton--arctodiaptomus salinus--non-predatory mortality--sediment--trap--carcasses--stratified lake
Аннотация: Zooplankton populations can at times suffer mass mortality due to non-predatory mortality (NPM) factors, and the resulting carcasses can be captured by sediment traps to estimate NPM rate. This approach assumes sinking to be the primary process in removing carcasses, but in reality, carcasses can also be removed by ingestion, turbulent mixing and microbial degradation in the water column. We present mathematical formulations to calculate NPM from sediment trap data by accounting for carcass removal by processes in addition to sinking, and demonstrate their application in a study in Lake Shira, Russia. Carcass abundance of the major calanoid copepod Arctodiaptomus salinus decreased with depth, indicating the effect of carcass removal from the water column. The estimated NPM values (0.0003-0.103 d(-1)) were comparable with previously reported physiological death rates. We further used independent data to partition carcass removal due to detritivory, turbulent mixing and microbial degradation. Estimated ingestion by the amphipod Gammarus lacustris could account for the disappearance of copepod carcasses above the traps. Wind-driven turbulence could also extend the carcass exposure time to microbial degradation. Collectively, these water column processes would facilitate the remineralization of carcasses in the water column, and diminish the carcass carbon flux to the benthos.
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10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Salmela, Anniina, Kokkonen, Eero, Kulmala, Ilpo, Veijalainen, Anna-Maria, van Houdt, Rob, Leys, Natalie, Berthier, Audrey, Viacheslav, Ilyin, Kharin, Sergey, Morozova, Julia, Tikhomirov, Alexander, Pasanen, Pertti
Заглавие : Production and characterization of bioaerosols for model validation in spacecraft environment
Колич.характеристики :12 с
Коллективы : European Union [263076]
Место публикации : J. Environ. Sci.: SCIENCE PRESS, 2018. - Vol. 69. - С. 227-238. - ISSN 1001-0742, DOI 10.1016/j.jes.2017.10.016. - ISSN 1878-7320(eISSN)
Примечания : Cited References:28. - The research leading to these results has received funding from the European Union Seventh Framework Programme (FP/2007-2013) under grant agreement number 263076 within the BIOSMHARS Project (BIO contamination Specific Modeling in Habitats Related to Space).
Предметные рубрики: INDOOR AIR
MICROBIAL-CONTAMINATION
BUILDING-MATERIALS
FUNGAL
Ключевые слова (''Своб.индексиров.''): bioaerosol--modeling--cfd--spacecraft--fungi--bacteria
Аннотация: This study aimed to evaluate the suitability of two bioaerosol generation systems (dry and wet generation) for the aerosolization of microorganisms isolated from the International Space Station, and to calibrate the produced bioaerosols to fulfill the requirements of computational fluid dynamics model (CFD) validation. Concentration, stability, size distribution, agglomeration of generated bioaerosol and deposition of bioaerosols were analyzed. In addition, the dispersion of non-viable particles in the air was studied. Experiments proved that wet generation from microbial suspensions could be used for the production of well-calibrated and stabile bioaerosols for model validation. For the simulation of the natural release of fungal spores, a dry generation method should be used. This study showed that the used CFD model simulated the spread of non-viable particles fairly well. The mathematical deposition model by Lai and Nazaroff could be used to estimate the deposition velocities of bioaerosols on surfaces, although it somewhat underestimated the measured deposition velocities. (c) 2017 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.
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11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shevyrnogov A. P., Botvich, I. Yu., Kononova N. A., Pis'man T. I.
Заглавие : Remote Ground-Based and Satellite Monitoring of Vegetation
Колич.характеристики :6 с
Коллективы : RAS Siberian Branch Integrated Basic Research Program "Interdisciplinary Integrative Studies" for 2018-2020 [74]
Место публикации : Her. Russ. Acad. Sci.: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2018. - Vol. 88, Is. 6. - С. 469-474. - ISSN 1019-3316, DOI 10.1134/S1019331618060138. - ISSN 1555-6492(eISSN)
Примечания : Cited References:20. - This study was performed within the RAS Siberian Branch Integrated Basic Research Program "Interdisciplinary Integrative Studies" for 2018-2020 (project no. 74) and a state assignment (state registration AAAA-A17-117013050027-1).
Предметные рубрики: GROWTH
Аннотация: Prospects for remote ground and satellite sensing to monitor agricultural (agrocenoses) and grass (meadows and steppes) vegetation are considered. This helps assess chlorophyll contents, crop yields, impurities of territories and identify agrocenoses. Investigation of vegetation on salinized soils identified the necessity to consider the succession of limiting factors (temperature and the degree of soil salinization). The results of studies on grassland plant communities in Khakassia based on geobotanical descriptions and ground spectral measurements are presented, allowing the refinement of methods that improve the accuracy of deciphering satellite images of medium and low resolutions.
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12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Belolipetskii V. M., Degermendzhi A. G., Genova S. N., Rogozin D. Y.
Заглавие : Change in the circulation regime in the stratified saline Lake Shira (Siberia, Republic of Khakassia)
Место публикации : Dokl. Earth Sci.: Maik Nauka-Interperiodica Publishing, 2017. - Vol. 474, Is. 2. - С. 649-652. - ISSN 1028334X (ISSN) , DOI 10.1134/S1028334X17060010
Ключевые слова (''Своб.индексиров.''): arid regions--lakes--mixing--climate scenarios--continental climate--in-situ data--incomplete mixing--simplified mathematical model--strong winds--vertical stratification--vertical structures--reservoirs (water)
Аннотация: The in-situ data on the vertical structure and stability of the vertical stratification of saline Lake Shira over the past decade (2007–2015) are analyzed. Simplified mathematical models have shown that strong wind in the autumn of 2014 together with rather thick ice in the winter of 2015 caused a change in the circulation regime of this water reservoir from meromictic (incomplete mixing) to holomictic (compete mixing). Based on the results obtained, a circulation regime for deep saline lakes located in the continental climate zone, in particular, in the arid zones of Southern Siberia (Khakassia, Transbaikal, and Altai) can be predicted under various climate scenarios of the future. © 2017, Pleiades Publishing, Ltd.
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13.

Вид документа : Статья из сборника (выпуск монографической серии)
Шифр издания :
Автор(ы) : Bartsev S., Belolipetskii P., Degermendzhi A.
Заглавие : Multistable states in the biosphere-climate system: towards conceptual models
Колич.характеристики :10 с
Коллективы : RFBR-KKFN [15-41-04300]; Complex Program of SB RAS [II.2, 0360-2015-0002]
Место публикации : V INTERNATIONAL WORKSHOP ON MATHEMATICAL MODELS AND THEIR APPLICATIONS: IOP PUBLISHING LTD, 2017. - Vol. 173: 5th International Workshop on Mathematical Models and their Applications (NOV 07-09, 2016, Krasnoyarsk, RUSSIA). - Ст.UNSP 012005. - (IOP Conference Series-Materials Science and Engineering). - , DOI 10.1088/1757-899X/173/1/012005
Примечания : Cited References:31. - This work was supported by grant RFBR-KKFN No 15-41-04300 and Complex Program of SB RAS No II.2. No 0360-2015-0002.
Предметные рубрики: SEA-SURFACE TEMPERATURE
1980S REGIME SHIFT
EL-NINO
PACIFIC
Аннотация: Forecasting response of the biosphere and regional ecosystems to observed and expected climate change is the fundamental problem with obvious practical significance. Fundamental non-linearity of the climate system and biosphere makes feasible implementing multiple states and threshold processes in the biosphere-climate system (BCS) in response to gradually increasing influence factor (greenhouse gas concentrations growth). Really time series analysis of global temperature and other global and local parameters indicates the presence of abrupt transitions between stationary states. Identification of the switching mechanisms using general circulation models of the atmosphere and the ocean is associated with the obvious difficulties due to their complexity. Understanding the nature of such switches at qualitative level can be achieved by using a conceptual small-scale models. Some variants of possible mechanisms capable of generating these shifts and simultaneously supporting quasi-stationary periods between them are discussed.
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14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bartsev S. I., Gitelson J. I.
Заглавие : A mathematical model of the global processes of plastic degradation in the World Ocean with account for the surface temperature distribution
Колич.характеристики :4 с
Коллективы : State Assignment for fundamental research of RAS [01201351502]
Место публикации : Dokl. Earth Sci.: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2016. - Vol. 466, Is. 2. - С. 153-156. - ISSN 1028-334X, DOI 10.1134/S1028334X16020033. - ISSN 1531-8354(eISSN)
Примечания : Cited References:12. - This work was financially supported in part by the State Assignment for fundamental research of RAS (project no. 01201351502).
Предметные рубрики: BIODEGRADATION
POLYMERS
SOIL
Аннотация: The suggested model of plastic garbage degradation allows us to obtain an estimate of the stationary density of their distribution over the surface of the World Ocean with account for the temperature dependence on the degradation rate. The model also allows us to estimate the characteristic time periods of degradation of plastic garbage and the dynamics of the mean density variation as the mean rate of plastic garbage entry into the ocean varies.
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15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Pis’man T. I., Botvich I. Y., Sid’ko A. F.
Заглавие : Evaluation of the seasonal dynamics of crop yield in agrocenoses on the basis of satellite data and mathematical models
Место публикации : Biol. Bull. - 2015. - Vol. 42, Is. 6. - С. 589-594. - ISSN 10623590 (ISSN) , DOI 10.1134/S1062359015660048
Аннотация: An integrated approach based on satellite remote-sensing data and the results of analysis of mathematical models has been tested for applicability in the evaluation of crop yield and total phytomass of agrocenosis, as well as identifying its type. The dynamics of the normalized difference vegetation index (NDVI) and the total aboveground phytomass of agrocenosis proved to be qualitatively similar. An analysis performed using a mathematical model and taking into account air temperature showed the possibility of making and refining the prognosis of crop yield. In this course, the vegetative and generative parts of the agrocenosis were distinguished, and it was found that model data matched ground survey data under optimal environmental conditions. © 2015, Pleiades Publishing, Inc.
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16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Prokopkin I.G., Barkhatov Y.V., Khromechek E.B.
Заглавие : A one-dimensional model for phytoflagellate distribution in the meromictic lake
Колич.характеристики :8 с
Коллективы : Russian Foundation for Basic Research (RFBR) [13-04-01514]; Integrative Project of Siberian Branch of Russian Academy of Sciences [56]
Место публикации : Ecol. Model.: ELSEVIER SCIENCE BV, 2014. - Vol. 288. - P1-8. - ISSN 0304-3800, DOI 10.1016/j.ecolmode1.2014.05.011. - ISSN 1872-7026
Примечания : Cited References: 22. - This work was supported by Russian Foundation for Basic Research (RFBR) No. 13-04-01514 and Integrative Project of Siberian Branch of Russian Academy of Sciences No. 56. The anonymous reviewers are kindly acknowledged for valuable suggestions and criticism.
Предметные рубрики: VERTICAL-DISTRIBUTION
CHLOROPHYLL MAXIMUM
SOUTH SIBERIA
RUSSIA
KHAKASIA
SHIRA
CRYPTOPHYTES
CRYPTOMONAS
CHEMOCLINE
MIGRATION
Ключевые слова (''Своб.индексиров.''): phytoflagellates--meromictic lake--simulation modeling--lake shira
Аннотация: Using mathematical modeling methods, the work investigates possible existence of a phytoflagellate population in the ecosystem of a stratified lake (Lake Shira, Khakasia, Russia). Until this study was carried out, no phytoflagellate population had been detected in the lake, although there had been indirect evidence of the possible presence of a cryptomonad population in this water body. To answer the question if this population may be present in this water body, as the first step of investigation, a mathematical model was developed describing the microorganism biomass dynamics and phytoflagellate relationship with the lake food web. The calculations showed that cryptophytic algae were abundant in the water column layers above the lake chemocline at the beginning of summer but showed low biomass concentrations during other periods of time. In the summer following the construction of the model, samples were collected from Lake Shira, as the next step of the study. A cryptophytic algae population was found in the water column, and the pattern of its distribution in the ecosystem was similar to that predicted by the model. In addition to that, we studied theoretically possible reasons for the early summer development of the population in the deep water layers and found that it was the result of the mixotrophic feeding strategy of cryptomonads and trophic interactions in the food web. The study shows that preliminary modeling of the locational and temporal distribution of populations whose presence in the ecosystem is only suggested by indirect evidence may be useful as a tool for searching for the species in natural ecosystems and as an approach enabling a more accurate description of the food web structure of a water body. (C) 2014 Elsevier B.V. All rights reserved.
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17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kartushinsky Alexei V.
Заглавие : Numerical modeling of the hydrophysical influence effects on the phytoplankton distribution
Место публикации : Mathematical Biology and Bioinformatics. - 2012. - Vol. 7, Is. 1. - С. 112-124. - ISSN 19946538 (ISSN)
Ключевые слова (''Своб.индексиров.''): aquatic ecosystem--biogenic element--chlorophyll--hydrophysical processes--inhomogeneity--numerical model--phytoplankton--rainfall--turbulent diffusion--upwelling--variability
Аннотация: The paper describes simulating results of the phytoplankton vertical distribution in the aquatic ecosystems based on one-dimensional numerical model. The model is used to calculate the dynamics of the temperature, salt, limiting nutrient and phytoplankton biomass. The work shows some temporal variability of phytoplankton distribution in the surface layer of salt and freshwater lake ecosystems under the impact of hydrophysical processes. These results can be used for the satellite date interpretation.
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18.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Barkhatov Y.V., Belolipetsky P.V., Degermendzhi A.G., Belolipetskii V.M., Verkhovets S.V., Timokhina A.V., Panov A.V., Shchemel A.L., Vedrova E.F., Trephilova O.V.
Заглавие : Modeling of CO2 fluxes between atmosphere and boreal forest
Место публикации : 18TH BIENNIAL ISEM CONFERENCE ON ECOLOGICAL MODELLING FOR GLOBAL CHANGE AND COUPLED HUMAN AND NATURAL SYSTEM. Ser. Procedia Environmental Sciences: ELSEVIER SCIENCE BV, 2012. - Vol. 13: 18th Biennial ISEM Conference on Ecological Modelling for Global Change and Coupled Human and Natural Systems (SEP 20-23, 2011, Beijing, PEOPLES R CHINA). - С. 621-625. - 5. - ISBN 1878-0296, DOI 10.1016/j.proenv.2012.01.053
Примечания : Cited References: 17
Предметные рубрики: CARBON-DIOXIDE FLUXES
SIBERIA
BUDGET
SINKS
RATIO
O-2
Ключевые слова (''Своб.индексиров.''): global carbon cycle--siberian boreal forests--mathematical modeling--atmospheric boundary layer budget method
Аннотация: Difficulties in estimating terrestrial ecosystem CO2 fluxes on regional scales have significantly limited our understanding of the global carbon cycle. We present a method of using tall-tower-based CO2 concentrations for estimating CO2 fluxes over a forested region. With long-term measurements of the CO2 mixing ratio at a 300-m-tall tower, regional CO2 fluxes were estimated for several months, from the first obtained data. Estimates of a monthly-integrated surface CO2 flux over the region were obtained by the analysis of average gradients and estimates of the rate of vertical mixing between the atmospheric boundary layer (ABL) and the free troposphere. For the comparison of the ABL budget method and field measurements a zero-dimensional mathematical model of the ecosystem of Siberian boreal forests was used. The model is a system of ordinary differential equations with additional conditions superimposed on the parameters. The main occurring processes are described - photosynthesis, respiration, seasonal changes of active phytomass, water balance of trees, the influence of light, humidity, and temperature on photosynthesis and respiration. (C) 2011 Published by Elsevier B. V. Selection and/or peer-review under responsibility of School of Environment, Beijing Normal University.
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19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Goreva A.V., Shishatskaya E.I., Volova T.G., Sinskey A.J.
Заглавие : Characterization of polymeric microparticles based on resorbable polyesters of oxyalkanoic acids as a platform for deposition and delivery of drugs
Место публикации : Polym. Sci. Ser. A: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2012. - Vol. 54, Is. 2. - С. 94-105. - 12. - ISSN 0965-545X, DOI 10.1134/S0965545X12020022
Примечания : Cited References: 33. - This work was supported by the program for Support of Leading Scientific Schools of the Russian Federation (project no. 11.G34.31.0013.2010, Biotechnology of New Biomaterials) and the program of integrated studies of the Presidium of the Siberian Branch, Russian Academy of Sciences (project no. 93).
Предметные рубрики: IN-VITRO RELEASE
POLYHYDROXYBUTYRATE MICROSPHERES
BLENDS
RIFAMPICIN
BIOCOMPATIBILITY
DEGRADATION
FORMULATION
COMPOSITE
CARRIERS
MODEL
Аннотация: The effect of the preparation technique (chemical composition of a polymer, type and method of emulsion mixing, and molecular mass of a drug) on the yield, structure, and size of microparticles obtained from resorbable polyesters of microbiological origin, polyhydroxyalkanoates, is studied. It is found that the concentration of the polymer solution and the method of emulsion mixing are the most significant factors affecting the diameter of microparticles based on polyhydroxyalkanoates; the surface structure of particles depends to a higher extent on the chemical composition of the polymer. The family of microparticles from 100-200 nm to 50-70 mu m in diameter is synthesized. It is shown that the rate of drug release from microparticles in vitro into the medium is higher in the case of 3-hydroxybutyrate copolymers with 3-hydroxyvalerate than in the case of the homopolymer of 3-hydroxybutyrate. This parameter increases with the content of 3-hydroxyvalerate units in the copolymer and the porosity and mass fraction of the drug in particles with a decrease in their sizes. For in vitro systems containing a phosphate buffer, variation in the preparation parameters makes it possible to obtain microparticles with various characteristics suitable for deposition of drugs. For microparticles obtained from polyhydroxyalkanoates and having different diameters, the mathematical description of the kinetics of drug release from the polymer matrix is provided.
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20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Genova S.N., Belolipetskii V.M., Rogozin D.Y., Degermendzhy A.G., Mooij W.M.
Заглавие : A one-dimensional model of vertical stratification of Lake Shira focussed on winter conditions and ice cover
Место публикации : Aquatic Ecology. - 2010. - Vol. 44, Is. 3. - С. 571-584. - ISSN 13862588 (ISSN) , DOI 10.1007/s10452-010-9327-7
Ключевые слова (''Своб.индексиров.''): convective mixed layer--ice formation--ice melting--simplified model--winter profiles--anoxic conditions--hydrogen sulfide--ice cover--inhomogeneity--meromictic lake--numerical model--one-dimensional modeling--pycnocline--salinity--seasonality--stratification--vertical profile--water column--water temperature--khakassia--lake shira--russian federation
Аннотация: In meromictic lakes such as Lake Shira, horizontal inhomogeneity is small in comparison with vertical gradients. To determine the vertical distribution of temperature, salinity, and density of water in a deep zone of a Lake Shira, or other saline lakes, a one-dimensional (in vertical direction) mathematical model is presented. A special feature of this model is that it takes into account the process of ice formation. The model of ice formation is based on the one-phase Stefan problem with the linear temperature distribution in the solid phase. A convective mixed layer is formed under an ice cover due to salt extraction in the ice formation process. To obtain analytical solutions for the vertical distribution of temperature, salinity, and density of water, we use a scheme of vertical structure in the form of several layers. In spring, the ice melts as top and bottom. These processes are taken into account in the model. The calculated profiles of salinity and temperature of Shira Lake are in good agreement with field measurement data for each season. Additionally, we focussed on the redox zone, which is the zone in which the aerobic layers of a water column meet the anaerobic ones. Hyperactivity of plankton communities is observed in this zone in lakes with hydrogen sulphide monimolimnion, and Lake Shira is among them. The location of the redox zone in the lake, which is estimated from field measurements, coincides with a sharp increase in density (the pycnocline) during autumn and winter. During spring and summer, the redox zone is deeper than the pycnocline. The location of pycnocline calculated with the hydro physical model is in good agreement with field measurement data. В© 2010 Springer Science+Business Media B.V.
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