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1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Барцев С.И., Гительзон И.И.
Заглавие : К вопросу о временной организации бактериальной люминесценции : научное издание
Место публикации : Stud. biophys. - 1985. - Т. 105, N 3. - С. 149-156. - ISSN 0081-6337
ГРНТИ : 34.17.09
Предметные рубрики: БИОЛЮМИНЕСЦЕНЦИЯ
МЕХАНИЗМЫ
МАТЕМАТИЧЕСКИЕ МОДЕЛИ
БАКТЕРИИ
BACTERIAS
BIOLUMINESCENCE
MATHEMATICAL MODELS
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2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Degermendzhy A.G., Zadereev E.S., Rogozin D.Y., Prokopkin I.G., Barkhatov Y.V., Tolomeev A.P., Khromechek E.B., Janse J.H., Mooij W.M., Gulati R.D.
Заглавие : Vertical stratification of physical, chemical and biological components in two saline lakes Shira and Shunet (South Siberia, Russia)
Место публикации : Aquatic Ecology. - 2010. - Vol. 44, Is. 3. - С. 619-632. - ISSN 13862588 (ISSN) , DOI 10.1007/s10452-010-9336-6
Ключевые слова (''Своб.индексиров.''): ciliates--cryptomonas--fishless lakes--gammarus--mathematical modelling--meromictic lakes--phytoplankton--stratification--sulphur bacteria--amphipod--bacterium--biomass--ciliate--ecosystem modeling--flagellate--meromictic lake--microbial community--numerical model--physicochemical property--phytoplankton--population density--saline lake--salinity--stratification--thermocline--trophic interaction--vertical profile--zooplankton--khakassia--lake shira--lake shunet--russian federation--siberia--amphipoda--bacteria (microorganisms)--ciliophora--copepoda--cryptomonas--cryptomonas sp.--gammaridae--gammarus--gammarus lacustris--phytomastigophorea--protista--rotifera
Аннотация: A feature of meromictic lakes is that several physicochemical and biological gradients affect the vertical distribution of different organisms. The vertical stratification of physical, chemical and biological components in saline, fishless meromictic lakes Shira and Shunet (Siberia, Russia) is quite different mainly because both mean depth and maximum depth of lakes differ as well as their salinity levels differ. The chemocline of the Lake Shira, as in many meromictic lakes, is inhabited by bacterial community consisting of purple sulphur and heterotrophic bacteria. As the depth of the chemocline is variable, the bacterial community does not attain high densities. The mixolimnion in Lake Shira, which is thermally stratified in summer, also creates different habitat for various species. The distribution of phytoplankton is non-uniform with its biomass peak in the metalimnion. The distribution of zooplankton is also heterogeneous with rotifers and juvenile copepods inhabiting the warmer epilimnion and older copepods found in the cold but oxic hypolimnion. The amphipod Gammarus lacustris which can be assigned to the higher trophic link in the fishless lake's ecosystem, such as Lake Shira, is also distributed non-uniformly, with its peak density generally observed in the thermocline region. The chemocline in Lake Shunet is located at the depth of 5 m, and unlike in Lake Shira, due to a sharp salinity gradient between the mixolimnion and monimolimnion, this depth is very stable. The mixolimnion in Lake Shunet is relatively shallow and the chemocline is inhabited by (1) an extremely dense bacterial community; (2) a population of Cryptomonas sp.; and (3) ciliate community comprising several species. As the mixolimnion of Lake Shunet is not thermally stratified for long period, the phytoplankton and zooplankton populations are not vertically stratified. The gammarids, however, tend to concentrate in a narrow layer located 1-2 m above the chemocline. We believe that in addition to vertical inhomogeneities of both physicochemical parameters, biological and physical factors also play a role in maintaining these inhomogeneities. We conclude that the stratified distributions of the major food web components will have several implications for ecosystem structure and dynamics. Trophic interactions as well as mass and energy flows can be significantly impacted by such heterogeneous distributions. Species spatially separated even by relatively short distances, say a few centimetres will not directly compete. Importantly, we demonstrate that not only bacteria, phytoflagellates and ciliate tend to concentrate in thin layers but also larger-sized species such Gammarus (amphipods) can also under certain environmental conditions have stratified distribution with maxima in relatively thin layer. As the vertical structure of the lake ecosystem is rather complex in such stratified lakes as ours, the strategy of research, including sampling techniques, should consider potentially variable and non-homogeneous distributions. В© 2010 The Author(s).
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3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Biel K.Y., Fomina I.R., Nazarova G.N., Soukhovolsky V.G., Khlebopros R.G., Nishio J.N.
Заглавие : Untangling metabolic and spatial interactions of stress tolerance in plants. 1. Patterns of carbon metabolism within leaves
Место публикации : Protoplasma. - 2010. - Vol. 245, Is. 1. - С. 49-73. - ISSN 0033183X (ISSN) , DOI 10.1007/s00709-010-0135-7
Ключевые слова (''Своб.индексиров.''): carbon metabolism--leaf anatomy--leaf form and function--maximal ecological utility--photosynthesis--stress tolerance spinacia oleracea--aspartate aminotransferase isoenzyme 1--bicarbonate--carbon--carbon dioxide--catalase--chlorophyll--malate dehydrogenase--oxygen--ribulosebisphosphate carboxylase--vegetable protein--article--enzymology--histology--light--metabolism--oxidation reduction reaction--photosynthesis--physiological stress--physiology--plant leaf--spinach--theoretical model--aspartate aminotransferase, cytoplasmic--bicarbonates--carbon--carbon dioxide--catalase--chlorophyll--light--malate dehydrogenase--models, theoretical--oxidation-reduction--oxygen--photosynthesis--plant leaves--plant proteins--ribulose-bisphosphate carboxylase--spinacia oleracea--stress, physiological--spinacia oleracea
Аннотация: The localization of the key photoreductive and oxidative processes and some stress-protective reactions within leaves of mesophytic C3 plants were investigated. The role of light in determining the profile of Rubisco, glutamate oxaloacetate transaminase, catalase, fumarase, and cytochrome-c-oxidase across spinach leaves was examined by exposing leaves to illumination on either the adaxial or abaxial leaf surfaces. Oxygen evolution in fresh paradermal leaf sections and CO2 gas exchange in whole leaves under adaxial or abaxial illumination was also examined. The results showed that the palisade mesophyll is responsible for the midday depression of photosynthesis in spinach leaves. The photosynthetic apparatus was more sensitive to the light environment than the respiratory apparatus. Additionally, examination of the paradermal leaf sections by optical microscopy allowed us to describe two new types of parenchyma in spinach-pirum mesophyll and pillow spongy mesophyll. A hypothesis that oxaloacetate may protect the upper leaf tissue from the destructive influence of active oxygen is presented. The application of mathematical modeling shows that the pattern of enzymatic distribution across leaves abides by the principle of maximal ecological utility. Light regulation of carbon metabolism across leaves is discussed. В© 2010 Springer-Verlag.
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4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Degermendzhy A.G., Gulati R.D.
Заглавие : Understanding the mechanisms of blooming of phytoplankton in Lake Shira, a saline lake in Siberia (the Republic of Khakasia)
Место публикации : Aquatic Ecology. - 2002. - Vol. 36, Is. 2. - С. 331-340. - ISSN 13862588 (ISSN)
Ключевые слова (''Своб.индексиров.''): carbon budget--cyanobacteria--heterotrophic bacteria--hydrogen sulphide--mathematical models of stratification--meromictic lakes--microbial loop--stratification--trophic scheme--algal bloom--ecosystem modeling--limiting factor--nutrient availability--phytoplankton--saline lake--trophic interaction--russian federation--algae--bacteria (microorganisms)--cyanobacteria--lyngbya--lyngbya contorta
Аннотация: The paper summarises the results of a three-year research study (European Union Grant: INTAS 97-0519) aimed at investigating the planktonic populations and trophic organization of the Lake Shira ecosystem - a saline lake in Khakasia, Siberia. The lake exhibits a stable summer-autumn stratification of the chemical-biological components. The mechanisms responsible for the 'blooming' of phytoplankton in the deeper layers were investigated in greater detail, using data from both field and laboratory experiments. The spectra of nutrition were examined to estimate the relationships between the specific growth rates of the hydrobionts and the influence of the limiting factors: light, nutrients. The observed heterotrophic capability of a metalimnetic phytoplankton population might help explain the development in the deeper waters of Lyngbya contorta. The scheme of trophic interactions was put up, based on the assessment of the carbon pools and carbon flows in the pelagic zone of the lake. A mathematical model of the vertical structure of the lake's plankton populations was constructed, using the ecosystem description and data of vertical turbulent diffusion. The role of light and nutrient limitations and grazing mortality in forming the vertical inhomogeneities, particularly in lowering the depth of the maximal cyanobacterial biomass, has been demonstrated. The theoretical curves for the stratification of chemical and biological parameters have been brought in conformity with the field observations, e.g. for the different patterns of the peaks, and for the biomass maxima of cyanobacteria, purple and green sulphur bacteria, oxygen, and hydrogen sulphide. The calculations revealed that for an adequate assessment of the parameters for the hydrogen sulphide zone it is necessary to introduce flows of allochthonous organic matter. Based on the form of the sulphur distribution curve, the allochthonous input of organic matter and the inflow of hydrogen sulphide from the bottom have been theoretically discriminated for the first time. It has also been ascertained that irrespective of the depth the allochthonous substances limiting bacterial growth, the bacteria are uniformly distributed over depth and can serve as an indicator of the presence of limitation (the effect of autostabilisation in space). Of indisputable interest to limnology are the specific methods developed for understanding the functioning of Lake Shira ecosystem. These include the autostabilisation of the limiting factors, the on-the-spot fluorescent method of determining the three classes of microalgae, the algal mixotrophy and the planktonic population interactions and feedbacks, and development of a more sensitive, bioluminescent method for mapping the nonhomogeneities. Owing to a balanced combination of classical approaches (field observations, in situ data on production-decomposition) and the more recent ones (satellite monitoring, biophysical methods of estimating interactions of populations, mathematical models based on the field and experimental data), many of the structural-function relationships in the ecosystem can now be explained, and the models can provide 'mutual control and mutual agreement' between the data collected using different approaches.
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5.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Degermendzhy A.G., Kosolapova L.G., Vlasik P.V.
Заглавие : Theory, computational method and software for prognosis of migration and distribution of radioactive matters in river ecosystem
Место публикации : COMPUTATIONAL METHODS IN WATER RESOURCES XI, VOL 2: COMPUTATIONAL METHODS IN SURFACE FLOW AND TRANSPORT PROBLEMS: COMPUTATIONAL MECHANICS PUBLICATIONS LTD, 1996. - 11th International Conference on Computational Methods in Water Resources (CMWR 96) (JUL, 1996, CANCUN, MEXICO). - С. 277-284. - 8. - ISBN 1-85312-487-7
Примечания : Cited References: 0
Ключевые слова (''Своб.индексиров.''): mathematical modelling--migration of radionuclides--river ecosystem
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6.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Degermendzhy N.N., Kosolapova L.G.
Заглавие : Theory and software of ecological-economical optimization of river water use
Колич.характеристики :8 с
Место публикации : COMPUTATIONAL METHODS IN WATER RESOURCES XI, VOL 2: COMPUTATIONAL METHODS IN SURFACE FLOW AND TRANSPORT PROBLEMS: COMPUTATIONAL MECHANICS PUBLICATIONS LTD, 1996. - 11th International Conference on Computational Methods in Water Resources (CMWR 96) (JUL, 1996, CANCUN, MEXICO). - P453-460. - ISBN 1-85312-487-7
Примечания : Cited References: 0
Ключевые слова (''Своб.индексиров.''): mathematical model--preparation of water--self-purification--optimization
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7.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Sadovsky M.G.
Заглавие : The method to compare nucleotide sequences based on the minimum entropy principle
Колич.характеристики :14 с
Место публикации : Bull. Math. Biol.: ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD, 2003. - Vol. 65, Is. 2. - P309-322. - ISSN 0092-8240, DOI 10.1016/S0092-8240(02)00107-6
Примечания : Cited References: 20
Предметные рубрики: GENOME
Аннотация: A new method to compare two (or several) symbol sequences is developed. The method is based on the comparison of the frequencies of the small fragments of the compared sequences; it requires neither string editing, nor other transformations of the compared objects. The comparison is executed through a calculation of the specific entropy of a frequency dictionary against the special dictionary called the hybrid one; this latter is the statistical ancestor of the group of sequences under comparison. Some applications of the developed method in the fields of genetics and bioinformatics are discussed. (C) 2003 Society for Mathematical Biology. Published by Elsevier Science Ltd. All rights reserved.
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8.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Degermendzhy A.G., Pechurkin N.S., Terskov I.A.
Заглавие : The mathematical theory of population waves (Russian)
Место публикации : Studia Biophysica. - 1974. - Vol. 43, Is. 1. - С. 25-40. - ISSN 00816337 (ISSN)
Ключевые слова (''Своб.индексиров.''): evolution--mathematical model--model--population explosion--population model--theoretical study
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9.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Kartushinsky A.V.
Заглавие : The investigation on the dynamics of frontal zones in the ocean based on the numerical modelling, using the AVHRR satellite data
Место публикации : CLIMATE CHANGE PROCESSES IN THE STRATOSPHERE, EARTH-ATMOSPHERE-OCEAN SYSTEMS, AND OCEANOGRAPHIC PROCESSES FROM SATELLITE DATA. Ser. ADVANCES IN SPACE RESEARCH: PERGAMON-ELSEVIER SCIENCE LTD, 2004. - Vol. 33: 2nd World Space Congress/34th COSPAR Scientific Assembly (OCT 10-19, 2002, HOUSTON, TX), Is. 7. - С. 1173-1178. - 6. - ISBN 0273-1177, DOI 10.1016/S0273-1177(03)00370-3
Примечания : Cited References: 19
Предметные рубрики: VARIABILITY
Ключевые слова (''Своб.индексиров.''): frontal temperature zones--model--numerical experiments--current velocity--turbulent diffusion--heat flow
Аннотация: The main purpose of the work is to investigate the frontal temperature zones using the mathematical model of the oceanic temperature field. The forecast of the frontal temperature zone variability is based on satellite data. The model calculates the temperature under different starting conditions and allows for the mean monthly intensity of solar radiation, components of current velocities, and turbulent diffusion. The input data are the mean monthly current velocities and the radiation heat flows. The model is used to calculate the dynamics of the frontal temperature zones in separate parts of the ocean. Based on the results of numerical experiments presented in the paper we estimated the spatial and temporal ranges of the frontal zone variation affected by the advection of currents, horizontal turbulent heat exchange, and the radiation heat flow in separate parts of the ocean. As examples we consider the basic frontal zones in the Atlantic and the Pacific Oceans. The work also shows possible applications of parametrization of spatial horizontal components of the frontal zones functionally related to the processes of heat advection and diffusion in the absence of exact information about the magnitudes of the current velocities and turbulent mixing. (C) 2003 COSPAR. Published by Elsevier Ltd. All rights reserved.
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10.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Kartushinsky A.V.
Заглавие : The investigation on the dynamics of frontal zones in the ocean based on the numerical modelling, using the AVHRR satellite data
Колич.характеристики :6 с
Место публикации : CLIMATE CHANGE PROCESSES IN THE STRATOSPHERE, EARTH-ATMOSPHERE-OCEAN SYSTEMS, AND OCEANOGRAPHIC PROCESSES FROM SATELLITE DATA. Ser. ADVANCES IN SPACE RESEARCH: PERGAMON-ELSEVIER SCIENCE LTD, 2004. - Vol. 33: 2nd World Space Congress/34th COSPAR Scientific Assembly (OCT 10-19, 2002, HOUSTON, TX), Is. 7. - P1173-1178. - ISBN 0273-1177, DOI 10.1016/S0273-1177(03)00370-3
Примечания : Cited References: 19
Предметные рубрики: VARIABILITY
Ключевые слова (''Своб.индексиров.''): frontal temperature zones--model--numerical experiments--current velocity--turbulent diffusion--heat flow
Аннотация: The main purpose of the work is to investigate the frontal temperature zones using the mathematical model of the oceanic temperature field. The forecast of the frontal temperature zone variability is based on satellite data. The model calculates the temperature under different starting conditions and allows for the mean monthly intensity of solar radiation, components of current velocities, and turbulent diffusion. The input data are the mean monthly current velocities and the radiation heat flows. The model is used to calculate the dynamics of the frontal temperature zones in separate parts of the ocean. Based on the results of numerical experiments presented in the paper we estimated the spatial and temporal ranges of the frontal zone variation affected by the advection of currents, horizontal turbulent heat exchange, and the radiation heat flow in separate parts of the ocean. As examples we consider the basic frontal zones in the Atlantic and the Pacific Oceans. The work also shows possible applications of parametrization of spatial horizontal components of the frontal zones functionally related to the processes of heat advection and diffusion in the absence of exact information about the magnitudes of the current velocities and turbulent mixing. (C) 2003 COSPAR. Published by Elsevier Ltd. All rights reserved.
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11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shirobokova I.M., Pechurkin N.S.
Заглавие : The effect of cannibalism intensity on net primary production and dynamics of trophic links in aquatic ecosystems
Место публикации : Advances in Space Research. - 2003. - Vol. 31, Is. 7. - С. 1737-1741. - ISSN 02731177 (ISSN) , DOI 10.1016/S0273-1177(03)00112-1
Ключевые слова (''Своб.индексиров.''): biomass--ecosystems--mathematical models--photosynthesis--cannibalism intensity--space research--aquatic ecosystem--cannibalism--ecological modeling--net primary production--trophic structure--amphipoda--animal--aquaculture--article--biological model--biomass--cannibalism--daphnia--ecosystem--food chain--microclimate--phytoplankton--zooplankton--amphipoda--animals--aquaculture--biomass--cannibalism--daphnia--ecological systems, closed--ecosystem--food chain--models, biological--phytoplankton--zooplankton
Аннотация: A mathematical model was used to investigate the effect of cannibalism intensity on the net primary production and the dynamics of trophic links in an aquatic ecosystem characterized by cannibalism at the upper trophic level. A mathematical model of an aquatic ecosystem has been constructed, with the following principal trophic links: limiting nutrient concentration, producers (phytoplankton), nonpredatory and predatory zooplankton. The model takes into account the age structure of the predator and includes two age groups (the young and adults). The adult predators are cannibals feeding on both nonpredatory zooplankton and their own young, which consume phytoplankton. It has been found that when cannibalism intensity increases above a certain level, the concentrations of both adults and the young of the predators decrease. At the same time, the concentrations of the nonpredatory zooplankton and of nutrients increase, while the biomass of producers decreases. When the cannibalism intensity is low, the net primary production of the system increases to a certain level correlated with the increase in cannibalism intensity and drops sharply when the level of consumption of young is high. There is an optimal intensity of cannibalism, at which the productivity in the photosynthesis link is maximal. В© 2003 COSPAR. Published by Elsevier Science Ltd. All rights reserved.
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12.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Shirobokova I.M., Pechurkin N.S.
Заглавие : The effect of cannibalism intensity on net primary production and dynamics of trophic links in aquatic ecosystems
Колич.характеристики :5 с
Место публикации : SPACE LIFE SCIENCES: CLOSED ARTIFICIAL ECOSYSTEMS AND LIFE SUPPORT SYSTEMS. Ser. ADVANCES IN SPACE RESEARCH: PERGAMON-ELSEVIER SCIENCE LTD, 2003. - Vol. 31: Meeting of F4 1 Session of the 34th Scientific Assembly of COSPAR (OCT, 2002, HOUSTON, TEXAS), Is. 7. - P1737-1741. - ISBN 0273-1177, DOI 10.1016/S0273-1177(03)00112-1
Примечания : Cited References: 13
Аннотация: A mathematical model was used to investigate the effect of cannibalism intensity on the net primary production and the dynamics of trophic links in an aquatic ecosystem characterized by cannibalism at the upper trophic level. A mathematical model of an aquatic ecosystem has been constructed, with the following principal trophic links: limiting nutrient concentration, producers (phytoplankton), nonpredatory and predatory zooplankton. The model takes into account the age structure of the predator and includes two age groups (the young and adults). The adult predators are cannibals feeding on both nonpredatory zooplankton and their own young, which consume phytoplankton. It has been found that when cannibalism intensity increases above a certain level, the concentrations of both adults and the young of the predators decrease. At the same time, the concentrations of the nonpredatory zooplankton and of nutrients increase, while the biomass of producers decreases. When the cannibalism intensity is low, the net primary production of the system increases to a certain level correlated with the increase in cannibalism intensity and drops sharply when the level of consumption of young is high. There is an optimal intensity of cannibalism, at which the productivity in the photosynthesis link is maximal. (C) 2003 COSPAR. Published by Elsevier Science Ltd. All rights reserved.
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13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : GITELSON I.I., GLADYSHEV M.I., DEGERMENDZHY A.G., LEVIN L.A., SIDKO F.Y.
Заглавие : THE ECOLOGICAL BIOPHYSICS AND ITS PART IN INVESTIGATION OF AQUATIC ECOSYSTEMS
Место публикации : Biofizika: MEZHDUNARODNAYA KNIGA, 1993. - Vol. 38, Is. 6. - С. 1069-1078. - 10. - ISSN 0006-3029
Примечания : Cited References: 11
Предметные рубрики: SEASONAL DYNAMICS
RESERVOIR
BAY
Аннотация: The notion of ecological biophysics as a scientific discipline investigating physical processes and phenomena caused by functioning of the living super-organism systems is formulated. The three main constituents of the ecological biophysics are defined: elaboration of the monitoring methods of the basis of sensing of the biophysical fields (of bioluminescence and fluorescence), mathematical and physical modeling and investigation of the part of living organisms in the hydrophysical processes of the ecosystem scale. Examples of realization of the ecological biophysical approach in the process of investigations of the World Ocean, Lake Baikal, the reservoirs of Dnieper and Yenisei revers are given.
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14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Pechurkin N.S., Shirobokova I.M.
Заглавие : System analysis of links interactions and development of ecosystems of different types
Место публикации : Advances in Space Research. - 2003. - Vol. 31, Is. 7. - С. 1667-1674. - ISSN 02731177 (ISSN) , DOI 10.1016/S0273-1177(03)80013-3
Ключевые слова (''Своб.индексиров.''): free energy--heuristic methods--hierarchical systems--mathematical models--photosynthesis--systems analysis--biological interactions--ecosystems--anthropogenic effect--ecosystem function--systems analysis--article--biological model--biomass--ecology--ecosystem--energy transfer--environmental protection--food chain--methodology--microclimate--plankton--population dynamics--statistics--biomass--conservation of natural resources--ecological systems, closed--ecology--ecosystem--energy transfer--food chain--models, biological--plankton--population dynamics
Аннотация: The anthropogenic impact on the Earth's ecosystems are leading to dramatic changes in ecosystem functioning and even to destruction of them. System analysis and the use of heuristic modeling can be an effective means to determine the main biological interactions and key factors that are of high importance for understanding the development of ecosystems. Cycling of limiting substances, induced by the external free energy flux, and trophic links interaction is the basis of the mathematical modeling studies presented in this paper. Mathematical models describe the dynamics of simplified ecosystems having different characteristics: 1) different degrees of biotic turnover closure (from open to completely closed); 2) different numbers of trophic links (including both "topdown", "bottom-up" regulation types); 3) different intensities of input - output flows of the limiting nutrient and its total amount in the system. Adaptive values of the changes of lower hierarchical levels (populational, trophic chain level) are to be estimated by integrity indices for total system functioning (e.g. NPP, total photosynthesis). The approach developed can be used for evaluating the contributions of lower hierarchical levels to the functioning of the higher hierarchical levels of the system. This approach may have value for determining biomanipulation management and their assessment. В© 2003 COSPAR. Published by Elsevier Science Ltd. All rights reserved.
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15.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Pechurkin N.S., Shirobokova I.M.
Заглавие : System analysis of links interactions and development of ecosystems of different types
Колич.характеристики :8 с
Место публикации : SPACE LIFE SCIENCES: CLOSED ARTIFICIAL ECOSYSTEMS AND LIFE SUPPORT SYSTEMS. Ser. ADVANCES IN SPACE RESEARCH: PERGAMON-ELSEVIER SCIENCE LTD, 2003. - Vol. 31: Meeting of F4 1 Session of the 34th Scientific Assembly of COSPAR (OCT, 2002, HOUSTON, TEXAS), Is. 7. - P1667-1674. - ISBN 0273-1177, DOI 10.1016/S0273-1177(03)00106-6
Примечания : Cited References: 12
Аннотация: The anthropogenic impact on the Earth's ecosysterns are leading to dramatic changes in ecosystem functioning and even to destruction of them. System analysis and the use of heuristic modeling can be an effective means to determine the main biological interactions and key factors that are of high importance for understanding the development of ecosysterns. Cycling of limiting substances, induced by the external free energy flux, and trophic links interaction is the basis of the mathematical modeling studies presented in this paper. Mathematical models describe the dynamics of simplified ecosysterns having different characteristics:1) different degrees of biotic turnover closure (from open to completely closed); 2) different numbers of trophic links (including both "top-down", "bottom-up" regulation types); 3) different intensities of input - output flows of the limiting nutrient and its total amount in the system. Adaptive values of the changes of lower hierarchical levels (populational, trophic chain level) are to be estimated by integrity indices for total system functioning (e.g. NPP, total photosynthesis). The approach developed can be used for evaluating the contributions of lower hierarchical levels to the functioning of the higher hierarchical levels of the system. This approach may have value for determining biomanipulation management and their assessment. (C) 2003 COSPAR. Published by Elsevier Science Ltd. All rights reserved.
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16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T.G., Voinov N.A.
Заглавие : Study of a Ralstonia eutropha culture producing polyhydroxyalkanoates on products of coal processing
Место публикации : Applied Biochemistry and Microbiology. - 2004. - Vol. 40, Is. 3. - С. 249-252. - ISSN 00036838 (ISSN) , DOI 10.1023/B:ABIM.0000025946.47013.03
Ключевые слова (''Своб.индексиров.''): alkanoic acid--carbon monoxide--coal--hydrogen--lignite--algorithm--article--bacterial strain--bacterium culture--coal gasification--controlled study--gas--gas exchange--mathematical computing--nonhuman--ralstonia eutropha--bacteria (microorganisms)--ralstonia--wautersia eutropha
Аннотация: Kinetic indices of growth, polyhydroxyalkanoate (PHA) accumulation, and gas exchange were studied in a culture of the carbon monoxide-resistant hydrogen strain Ralstonia eutropha B-5786 grown on a gaseous substrate (GS) obtained by lignite gasification. The GS was shown to be suitable for PHA production. To increase the degree of GS consumption, various modes of gas supply to the culture were tested. Based on the results, an algorithm was developed for calculating and controlling gas-exchange parameters in the PHA-accumulating culture of Ralstonia eutropha, grown on a new GS allowing high polymer yields (up to 75%) and degrees of substrate utilization (up to 90%).
Scopus
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17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ganusov V.V., Bril'kov A.V., Pechurkin N.S.
Заглавие : Structured approach to mathematical modeling of unstable multicopy plasmidcontaining bacteria population dynamics
Колич.характеристики :4 с
Место публикации : Dokl. Akad. Nauk: MEZHDUNARODNAYA KNIGA, 1999. - Vol. 369, Is. 2. - P267-270. - ISSN 0869-5652
Примечания : Cited References: 15
Предметные рубрики: PLASMIDS
BIOLOGY
WOS
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18.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Bartsev S.I.
Заглавие : Stoichiometric constraints and complete closure of long-term life support systems
Колич.характеристики :8 с
Место публикации : SPACE LIFE SCIENCES: LIFE SUPPORT SYSTEMS AND BIOLOGICAL SYSTEMS UNDER INFLUENCE OF PHYSICAL FACTORS. Ser. ADVANCES IN SPACE RESEARCH: PERGAMON-ELSEVIER SCIENCE LTD, 2004. - Vol. 34: 2nd World Space Congress/34th COSPAR Scientific Assembly (OCT 10-19, 2002, HOUSTON, TX), Is. 7. - P1509-1516. - ISBN 0273-1177, DOI 10.1016/j.asr.2003.04.069
Примечания : Cited References: 14
Ключевые слова (''Своб.индексиров.''): long-term life support systems--stoichiometric constraints
Аннотация: High closure of matter recycling is an obvious requirement for long-term life support systems (LSS). Biological species are obligate components of the LSS since physical/chemical components are not able yet to provide food for crew. However including biological species into LSS is difficult due to specific stoichiometric configuration of their inputs and outputs. Formally the problem is to estimate the ability for given set of species to provide complete closure of LSS. Two possible models of metabolism organization can be considered: rigid and flexible ones. Stoichiometric analyses showed that the rigid metabolism case is not typical and takes place with very specific requirements. The flexible metabolic model can be applied to describing wide range of systems. Some formal indications of ability to provide complete closure and stationarity of LSS state are considered in the paper. These indications establish some constraints on the form of mathematical models intended to describe artificial and natural ecological systems. (C) 2004 COSPAR. Published by Elsevier Ltd. All rights reserved.
WOS
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19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Rogozin D.Y., Genova S.N., Gulati R.D., Degermendzhy A.G.
Заглавие : Some generalizations based on stratification and vertical mixing in meromictic Lake Shira, Russia, in the period 2002-2009
Место публикации : Aquatic Ecology. - 2010. - Vol. 44, Is. 3. - С. 485-496. - ISSN 13862588 (ISSN) , DOI 10.1007/s10452-010-9328-6
Ключевые слова (''Своб.индексиров.''): 1-d model--meromixis--mixolimnion--oxic-anoxic interface--thermocline--weather conditions--brackish water--meromictic lake--numerical model--one-dimensional modeling--overturn--physicochemical property--salinity--seasonality--stratification--temperate environment--vertical mixing--water temperature--weather--khakassia--lake shira--russian federation
Аннотация: In a brackish, temperate, 24-m-deep Lake Shira, the profiles of salinity, temperature, oxygen and sulfide concentrations were measured on a seasonal basis from 2002 to 2009. The lake was shown to be meromictic with autumnal overturn restricted to mixolimnion. The depth of mixolimnion and position of oxic-anoxic interface varied annually. The spring mixing processes contribute to the formation of mixolimnion in autumn. The exceptionally windy spring of 2007 caused the deepening of mixolimnion in the winter of 2008. The winter position of oxic-anoxic interface was affected by the position of lower boundary of mixolimnion in all winters. The salinity in the winter mixolimnion increased compared with the autumn because of freezing out of salts from the upper water layers meters during ice formation and their dissolution in water below. The profiles of salinity and temperature were simulated by the mathematical 1-D model of temperature and salinity conditions taking into account ice formation. The simulated profiles generally coincided with the measured ones. The coincidence implies that simplified one-dimensional model can be applied to roughly describe salinity and density profiles and mixing behavior of Lake Shira. В© 2010 The Author(s).
Scopus
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20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gitelson I.I., Degermendzhy A.G., Rodicheva E.K.
Заглавие : Self-restoration as fundamental property of CES providing their sustainability
Место публикации : Advances in Space Research. - 2003. - Vol. 31, Is. 7. - С. 1641-1648. - ISSN 02731177 (ISSN) , DOI 10.1016/S0273-1177(03)00111-X
Ключевые слова (''Своб.индексиров.''): biocatalysts--ecosystems--genes--life support systems (spacecraft)--radiation damage--cell populations--space flight--space shuttle--article--biological model--biomass--cell division--chlorella--cytology--growth, development and aging--microclimate--radiation exposure--radiation response--ultraviolet radiation--biomass--cell division--chlorella--dose-response relationship, radiation--ecological systems, closed--life support systems--models, biological--ultraviolet rays
Аннотация: Sustainability is one of the most important criteria and evaluation of human life support systems intended for use during long space flights. The common feature of biological and physicochemical life support systems is that basically they are both catalytic. But there are two fundamental properties distinguishing biological systems: 1) they are auto-catalytic: their catalysts - enzymes of protein nature - are continuously reproduced when the system functions; 2) the program of every process performed by enzymes and the program of their reproduction are inherent in the biological system itself - in the totality of genomes of the species involved in the functioning of the ecosystem. Actually, one cell with the genome capable of the phenotypic realization is enough for the self-restoration of the function performed by the cells of this species in the ecosystem. The continuous microalgal culture of Chlorella vulgaris was taken to investigate quantitatively the process of self-restoration in unicellular algae population. Based on the data obtained, we proposed a mathematical model of the restoration process in a cell population that has suffered an acute radiation damage. В© 2003 COSPAR. Published by Elsevier Science Ltd. All rights reserved.
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