Главная
Авторизация
Фамилия
Пароль
 

Базы данных


Труды сотрудников ИБФ СО РАН - результаты поиска

Вид поиска

Область поиска
в найденном
Формат представления найденных документов:
полный информационныйкраткий
Отсортировать найденные документы по:
авторузаглавиюгоду изданиятипу документа
Поисковый запрос: (<.>K=Biomass<.>)
Общее количество найденных документов : 261
Показаны документы с 1 по 20
 1-20    21-40   41-60   61-80   81-100   101-120      
1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bolsunovsk A.Ya., Kosinenko S.V.
Заглавие : Intracellular phosphorus pool of the cyanobacterium spirulina platensis
Место публикации : Mikrobiologiya. - 2000. - Vol. 69, Is. 1. - С. 135-137. - ISSN 00263656 (ISSN)
Ключевые слова (''Своб.индексиров.''): phosphorus--article--biomass--cyanobacterium--growth, development and aging--metabolism--biomass--cyanobacteria--phosphorus
Аннотация: An intracellular phosphorus pool in a monoculture of the cyanobacterium Spirulina platensis was assessed using radioactive and nonradioactive phosphorus. The derived dependence of specific growth rate on the intracellular content of mineral phosphorus can be presented in the form of the Droop equation. It was found that the stage of replenishment of the intracellular phosphorus pool may affect the phosphorus turnover estimation in aquatic environments from the results of short-term measurements of phosphorus uptake.
Scopus
Найти похожие
2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bolsunovskii A.Ya., Zotina T.A., Bondareva L.G., Degermendzhi A.G.
Заглавие : Assessment of the rate of accumulation of the transuranium element americium-241 by the aquatic plant Elodea canadensis
Место публикации : Doklady Biological Sciences. - 2004. - Vol. 399, Is. 1-6. - С. 467-469. - ISSN 00124966 (ISSN) , DOI 10.1007/s10630-005-0014-0
Ключевые слова (''Своб.индексиров.''): americium--radioisotope--water--article--biomass--drug effect--environmental monitoring--hydrocharitaceae--methodology--ph--plant--plant root--radiation exposure--radiochemistry--time--toxicity testing--water pollutant--americium--biomass--environmental monitoring--hydrocharitaceae--hydrogen-ion concentration--plant roots--plant shoots--plants--radiochemistry--radioisotopes--time factors--toxicity tests--water--water pollutants, radioactive--elodea canadensis
Scopus
Найти похожие
3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zotina T., Trofimova E., Dementyev D., Bolsunovsky A.
Заглавие : Transfer of americium-241 from food and water to organs and tissues of the crucian carp *
Место публикации : Radioprotection. - 2011. - Vol. 46, Is. 6 SUPPL. - С. S69-S73. - ISSN 00338451 (ISSN) , DOI 10.1051/radiopro/20116648s
Аннотация: The transfer of transuranium element americium-241 (241Am) from food and water to organs and tissues of freshwater fish (Carassius auratus gibelio, crucian carp) has been investigated in laboratory experiments. The fishes were fed with homogenized biomass of submerged macrophytes labeled with 241Am, through catheter. For the first two days after force-feeding, fishes excreted up to 80% of ingested americium, for four days - 98%. 241Am was registered in internal organs and tissues that had no direct contact with americium (liver, bones, muscles) as early as two days after the feeding and after eight days, when the digestive tract was depurated. Among internal organs, the highest activity concentration was recorded in the liver (up to 427 Bq/kg). Activity concentration in bones (19-31 Bq/kg) was several times higher than in muscles, indicating the affinity of americium to bone tissue. Assimilation of 241Am in organs and tissues of crucian carp from water occurred mainly via the digestive tract too. В© 2011 EDP Sciences.
Scopus
Найти похожие
4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bolsunovsky A.
Заглавие : Chemical fractionation of radionuclides and stable elements in aquatic plants of the yenisei river
Место публикации : Environmental Science and Technology. - 2011. - Vol. 45, Is. 17. - С. 7143-7150. - ISSN 0013936X (ISSN) , DOI 10.1021/es2008853
Ключевые слова (''Своб.индексиров.''): aquatic plants--artificial radionuclides--cell structure--chemical fractionation--distribution patterns--nuclear plant--plant biomass--sequential extraction scheme--stable elements--submerged plants--transuranic elements--americium--biomass--neptunium--river pollution--rivers--radioisotopes--americium--element--neptunium--radioisotope--bioaccumulation--chemical binding--gamma ray spectrometry--isotopic fractionation--monocotyledon--phytomass--radionuclide--river pollution--submerged vegetation--aquatic species--article--batrachium kauffmanii--biomass--cell structure--controlled study--extraction--fontinalis antipyretica--fractionation--gamma spectrometry--higher plant--nonhuman--plant growth--potamogeton lucens--potamogetonaceae--river--russian federation--aquatic organisms--biomass--chemical fractionation--china--industrial waste--plants--radiation monitoring--radioisotopes--rivers--water pollutants, radioactive--russian federation--yenisei river--batrachium--fontinalis antipyretica--potamogeton lucens
Аннотация: The Yenisei River is contaminated with artificial radionuclides released by one of the Russian nuclear plants. The aquatic plants growing in the radioactively contaminated parts of the river contain artificial radionuclides. The aim of the study was to investigate accumulation of artificial radionuclides and stable elements by submerged plants of the Yenisei River and estimate the strength of their binding to plant biomass by using a new sequential extraction scheme. The aquatic plants sampled were: Potamogeton lucens, Fontinalis antipyretica, and Batrachium kauffmanii. Gamma-spectrometric analysis of the samples of aquatic plants has revealed more than 20 radionuclides. We also investigated the chemical fractionation of radionuclides and stable elements in the biomass and rated radionuclides and stable elements based on their distribution in biomass. The greatest number of radionuclides strongly bound to biomass cell structures was found for Potamogeton lucens and the smallest for Batrachium kauffmanii. For Fontinalis antipyretica, the number of distribution patterns that were similar for both radioactive isotopes and their stable counterparts was greater than for the other studied species. The transuranic elements 239Np and 241Am were found in the intracellular fraction of the biomass, and this suggested their active accumulation by the plants. В© 2011 American Chemical Society.
Scopus
Найти похожие
5.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bondareva L., Bolsunovsky A.
Заглавие : Bioavailability of 99Tc to a macrophyte of the Yenisei River
Место публикации : Radioprotection. - 2009. - Vol. 44, Is. 5. - С. 71-76. - ISSN 00338451 (ISSN) , DOI 10.1051/radiopro/20095019
Аннотация: The experiments on accumulation of 99Tc by Elodea biomass showed that 99Tc activity concentration can reach 120 В± 6Bq/g, with the concentration factor for 99Tc 2700 В± 500 L/kg. In experiments on 99Tc release, over 504 h about 82% of the total 99Tc activity was released into the water from plant biomass; most of 99Tc was released within the first 192 h. Results of chemical fractionation of the biomass show that 99Tc contained in biomass was mainly concentrated in the exchangeable and the adsorbed fractions (83%). Thus, the data obtained using chemical fractionation of biomass confirmed the experimental data on 99Tc release, which suggested that most of the biomass-bound 99Tc was adsorbed on the biomass surface. 99Tc tightly bound to Elodea biomass (fractions of organics and mineral residue) constituted just 17% of the total 99Tc activity. Decreased illumination of Elodea shoots during the experiment did not cause any reduction in 99Tc activity concentration or concentration factor. Results of chemical fractionation of the biomass grown under lower illumination conditions show that the percentage of 99Tc tightly bound to Elodea biomass (fractions of organics and mineral residue) decreased while the 99Tc of the adsorbed fractions decreased. Our results and data reported by other authors suggest that some part of 99Tc activity can be bioavailable to living organisms and that the portion of bioavailable 99Tc can be determined by a number of factors. В© 2009 EDP Sciences.
Scopus
Найти похожие
6.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bolsunovsky A., Bondareva L., Sukhorukov F., Melgunov M.
Заглавие : Accumulation of 242Pu by a macrophyte of the Yenisei River (Elodea canadensis) in laboratory experiments
Место публикации : Chemosphere. - 2009. - Vol. 75, Is. 3. - С. 284-288. - ISSN 00456535 (ISSN) , DOI 10.1016/j.chemosphere.2008.12.036
Ключевые слова (''Своб.индексиров.''): 242pu--accumulation--laboratory experiments--sequential extraction technique--submerged plant elodea canadensis--yenisei river--sup242/suppu--accumulation--laboratory experiments--sequential extraction technique--submerged plant elodea canadensis--yenisei river--biological materials--biomass--chemical plants--experiments--positive ions--rivers--plutonium--concentration (composition)--experimental study--laboratory method--macrophyte--plutonium isotope--river water--submerged vegetation--eurasia--russian federation--yenisei river--plutonium--article--biomass--chemistry--hydrocharitaceae--physiology--plant--radiation monitoring--river--time--water pollutant--biomass--hydrocharitaceae--plant shoots--plutonium--radiation monitoring--rivers--time factors--water pollutants, radioactive
Аннотация: The study addresses 242Pu accumulation by Elodea canadensis, one of the abundant species of submerged plants in the Yenisei River. 242Pu in water samples of the "Elodea - Yenisei River water" model system and in the biomass fractions was determined ?-spectrometrically, following radiochemical recovery of 242Pu using 236Pu - a chemical yield tracer. The experiments on accumulation of 242Pu by Elodea biomass showed that the activity concentration of 242Pu can reach 21 В± 2 Bq/g dry wt, with the concentration factor for 242Pu 13100 В± 2100 L/kg dry wt. Results of chemical fractionation proved that during the first few hours of the experiment 242Pu contained in Elodea was mainly concentrated in the exchangeable and the adsorbed fractions of biomass (about 100%). As Elodea biomass accumulated 242Pu, the absolute amount of 242Pu in the exchangeable and the adsorbed fractions remained almost unchanged, although the portion of 242Pu tightly bound to biomass increased. At the end of the experiment, on day 7, 242Pu tightly bound to biomass (fractions of organics and mineral residue) constituted 43-63% (in different experiments) of the total 242Pu in the biomass. В© 2008 Elsevier Ltd. All rights reserved.
Scopus
Найти похожие
7.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bolsunovsky A., Bondareva L.
Заглавие : Accumulation and release of 99Tc by a macrophyte of the Yenisei River (Elodea canadensis) in laboratory experiments
Место публикации : Journal of Radioanalytical and Nuclear Chemistry. - 2008. - Vol. 277, Is. 3. - С. 631-636. - ISSN 02365731 (ISSN) , DOI 10.1007/s10967-007-7148-5
Ключевые слова (''Своб.индексиров.''): technetium 99m--aquatic flora--article--biomass--controlled study--dry weight--liquid scintillation counting--macrophyte--nonhuman--radiation absorption--radiation detection--radiation dose fractionation--radiation measurement--radioactivity--river--water sampling
Аннотация: The study addresses 99Tc accumulation and release by Elodea canadensis, one of the abundant species of submerged plants in the Yenisei River. 99Tc in water samples of the "Elodea - Yenisei River water" model system and in the biomass fractions was measured using a liquid scintillation analyzer. Experiments on accumulation of 99Tc by Elodea showed that 99Tc activity concentration can reach 120В±6 Bq/g dry wt, with the concentration factor for 99Tc 2700В±500 l/kg dry wt. In experiments on 99Tc release, over 504 hours about 82% of the total 99Tc activity was released into the water from the plant; most of 99Tc was released within the first 192 hours. The data obtained using sequential chemical fractionation of biomass confirmed the experimental data on 99Tc release, which suggested that most of the biomass-bound 99Tc was adsorbed on the surface of Elodea. 99Tc tightly bound to biomass (fractions of organics and mineral residue) constituted just 17% of the total 99Tc activity. В© 2008 Akademiai Kiado, Budapest.
Scopus
Найти похожие
8.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bolsunovsky A., Bondareva L.
Заглавие : Actinides and other radionuclides in sediments and submerged plants of the Yenisei River
Место публикации : Journal of Alloys and Compounds. - 2007. - Vol. 444-445, Is. SPEC. ISS. - С. 495-499. - ISSN 09258388 (ISSN) , DOI 10.1016/j.jallcom.2007.01.146
Ключевые слова (''Своб.индексиров.''): accumulation--actinides in aquatic plants and sediments--radiochemical and ?-spectrometric investigations--sequential extraction technique--yenisei river--actinides--bioaccumulation--plants (botany)--radioisotopes--rivers--sampling--sediments--mining-and-chemical combine (mcc)--radiochemical and spectrometric investigations--sediment samples--sequential extraction techniques--contamination
Аннотация: The source of radioactive contamination of the Yenisei River floodplain, including contamination with actinides, is the Mining-and-Chemical combine (MCC), which has for many years been producing weapons-grade plutonium. Actinides have been detected not only in the soil and sediment of the river but also in the biomass of aquatic plants. The aim of our investigation was to assess the levels of actinides and other radionuclides in sediments and aquatic plants both near the MCC and at a considerable distance from it, down the Yenisei River. Investigations of the Yenisei River sediment samples revealed high activity concentrations of actinides (Pu isotopes and 241Am), which were 100 times higher than their global fallout levels. Sequential extraction of radionuclides from samples of sediments collected near the MCC showed that the amounts of extracted 241Am were the largest (up to 98% of initial activity). It was found that aquatic plants of the Yenisei River collected both near the MCC discharge site and at a distance up to 200 km downstream contained several actinide isotopes. The aquatic moss, Fontinalis antipyretica, was found to contain higher levels of radionuclides than Potamogeton lucens. Leaves of P. lucens contained higher levels of radionuclides, including 239Np, than stems. Sequential extraction of radionuclides from samples of aquatic plants showed that 239Np levels in exchangeable and adsorption fractions of P. lucens biomass were higher than in the respective fractions of F. antipyretica biomass. В© 2007 Elsevier B.V. All rights reserved.
Scopus
Найти похожие
9.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bolsunovsky A., Zotina T., Bondareva L.
Заглавие : Accumulation and release of 241Am by a macrophyte of the Yenisei River (Elodea canadensis)
Место публикации : Journal of Environmental Radioactivity. - 2005. - Vol. 81, Is. 1. - С. 33-46. - ISSN 0265931X (ISSN) , DOI 10.1016/j.jenvrad.2004.10.012
Ключевые слова (''Своб.индексиров.''): 241am--accumulation--laboratory experiments--release--submerged plant elodea canadensis--yenisei river--activation analysis--biomass--concentration (process)--effluents--plutonium--rivers--aquatic plants--elodea plant--macrophytes--radioactive contamination--transuranium elements--americium 241--river water--americium--americium nitrate--bioaccumulation--biological uptake--macrophyte--pollutant source--radioactive pollution--river water--submerged vegetation--article--biomass--concentration (parameters)--environmental factor--fractionation--laboratory--macrophyte--radioactivity--river--sampling--adsorption--chemistry--hydrocharitaceae--methodology--physiology--plant--radiation exposure--radiation monitoring--russian federation--sediment--soil pollutant--time--tissue distribution--water pollutant--eastern hemisphere--eurasia--russian federation--world--yenisei river--elodea canadensis--adsorption--americium--biomass--chemical fractionation--geologic sediments--hydrocharitaceae--plant shoots--radiation monitoring--rivers--russia--soil pollutants, radioactive--time factors--tissue distribution--water pollutants, radioactive
Аннотация: The source of radioactive contamination of the Yenisei River floodplain, including contamination with transuranic elements, is the Mining-and-Chemical Combine of the Russian Ministry of Atomic Energy, which has for many years been producing weapons-grade plutonium. Transuranic elements have been detected not only in the soil and sediment of the river but also in the biomass of aquatic plants. This work is an investigation of accumulation and release of 241Am by a submerged macrophyte of the Yenisei River (Elodea canadensis) in laboratory experiments. In 2000-2003, laboratory experiments were carried out with biomass of E. canadensis Mich. and filtered river water. The samples were collected from the Yenisei River upstream of the discharge of the Combine's radioactive effluent. The experiments showed that 241Am is accumulated by Elodea biomass: the activity concentration of 241Am can reach 3280 В± 240 Bq/g, with the concentration factor for 241Am 16 600 В± 2200 l/kg. Results of chemical fractionation have proved that in the course of 241Am accumulation by Elodea biomass, 241Am tightly bound to biomass increases from 11% to 27% of the total 241Am in the biomass. Release of 241Am from the decaying Elodea biomass has been evaluated experimentally. By the end of the experiment (lasting up to 127 days), the Elodea plants had lost up to 65% of their initial 241Am activity and the rate of 241Am release into the water environment reached 23 Bq/day. В© 2004 Elsevier Ltd. All rights reserved.
Scopus
Найти похожие
10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bolsunovsky A., Muratova E., Sukovaty A., Kornilova M.
Заглавие : The effect of radionuclide and heavy metal contamination of the Yenisei River on cytogenetics of aquatic plant Elodea canadensis
Место публикации : Radioprotection. - 2009. - Vol. 44, Is. 5. - С. 83-88. - ISSN 00338451 (ISSN) , DOI 10.1051/radiopro/20095021
Аннотация: The study was done to determine concentrations of radionuclides and heavy metals and to evaluate the frequency of chromosomal aberrations in samples of Elodea canadensis, a submerged plant, collected in different parts of the Yenisei River. Samples were collected in the area subjected to radioactive impact of theMining-and-Chemical Combine (MCC) at Zheleznogorsk and in the control areas, upstream of the MCC. The investigations showed that Elodea biomass in the area affected by MCC operation contained a long inventory of artificial radionuclides typical of the MCC discharges. Upstream of the MCC, in the control sampling areas, the sediments and the Elodea biomass contained only one artificial radionuclide - 137Cs. Thus, the exposure doses to Elodea shoots and roots upstream of the MCC are small (not more than 8 ?Gy/d) and the main contribution to them is made by natural radionuclides. At the MCC discharge site (the village of Atamanovo) and downstream of it, the total dose rate increases almost an order of magnitude, reaching its maximal values - 72 ?Gy/d for Elodea shoots and 58 ? Gy/d for roots. Cytogenetic investigations of Elodea roots showed that at the MCC discharge site (the village of Atamanovo) and downstream of it the occurrence of chromosomal aberrations in ana-telophase and metaphase cells of Elodea was considerably higher than in the control area. It is highly probable that this simultaneous dramatic increase in the total exposure rate and the occurrence of chromosomal aberrations in Elodea is associated with the radiation factor. It is suggested that Elodea is affected not only by the radiation factor but also by the chemical factor - toxicity of heavy metals. В© 2009 EDP Sciences.
Scopus
Найти похожие
11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bolsunovskii A.Ya., Aleksandrova Yu.V., Degermendzhi A.G.
Заглавие : First data on technetium-99 content in the ecosystem of the Yenisei River
Место публикации : Doklady Earth Sciences. - 2010. - Vol. 434, Is. 1. - С. 1219-1221. - ISSN 1028334X (ISSN) , DOI 10.1134/S1028334X10090163
Ключевые слова (''Своб.индексиров.''): aquatic plants--concentration factors--dumping site--filtered water--laboratory conditions--maximal values--radioactive effluents--technetium 99--ecology--effluents--sewage--technetium--wastewater--water content--aquatic plant--bioaccumulation--freshwater ecosystem--radioactive pollution--river water--technetium isotope--russian federation--yenisei river--potamogeton lucens
Аннотация: The content of a long-lived technogenic radionuclide 99Tc in the Yenisei within the territory of radioactive effluents of the Rosatom mining chemical combine (MCC) has been studied. In 2008-2009 the maximal 99Tc content in water was registered near the dumping site of the MCC and came to 33 mBq/l. According to analysis of filtered water samples, technetium in the Yenisei water is presented as pertechnetate ion (TcO 4). When moving away from the MCC downstream, the 99Tc content in water is decreased, which is caused both by dilution of waste water and by 99Tc accumulation by aquatic plants. The 99Tc content in the biomass of the aquatic plant Potamogeton lucens came to 82 15 Bq/kg, and the concentration factor (CF) to 8200, which is three times more than the maximal values of the CF of 99Tc by the plants in laboratory conditions (2700). В© 2010 Pleiades Publishing, Ltd.
Scopus
Найти похожие
12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Rogozin D.Y., Zykov V.V., Degermendzhi A.G.
Заглавие : Ecology of purple sulfur bacteria in the highly stratified meromictic Lake Shunet (Siberia, Khakassia) in 2002-2009
Место публикации : Microbiology (Russian Federation). - 2012. - Vol. 81, Is. 6. - С. 727-735. - ISSN 00262617 (ISSN) , DOI 10.1134/S0026261712060148
Ключевые слова (''Своб.индексиров.''): bacteriochlorophyll a--chemocline--meromictic lake--purple sulfur bacteria--seasonal dynamics--bacteria (microorganisms)--chromatiaceae
Аннотация: Phototrophic sulfur bacteria form dense accumulations in the chemocline zones of stratified lakes where light reaches the sulfide-containing layers of water. Many works are dedicated to the ecophysiology of these microorganisms in meromictic lakes. However, the role of these microorganisms in the trophic network of these ecosystems, the ways of biomass utilization, and the contribution to the turnover of biogenic elements have so far been insufficiently understood. This work deals with the analysis of many years' seasonal dynamics of the biomass of purple sulfur bacteria and the physicochemical conditions of their environment in Lake Shunet (Siberia, Khakassia, Russia), unraveling the causes of their anomalous development in the chemocline of this lake, as well as the comparative analysis of such type of ecosystems. Lake Shunet is characterized by markedly pronounced stratification and the high density of purple sulfur bacteria (PSB) in the chemocline, which is comparable to that of Lake Mahoney (Canada) where the number of PSB is the greatest among those known in the world. It was shown that, in the period 2002-2009, the total amount of bacterio-chlorophyll a in the water column of Lake Shunet increased and did not correlate with the seasonal variations in temperature and illumination in the chemocline. It was established that PSB cells in the purple layer experienced the effect of self-shading. The sedimentation rate of purple sulfur bacteria in Lake Shunet was low due to the pronounced density gradient in the chemocline zone. Thus, the high number of PSB in the chemocline was due to the combination of strong illumination, a high sulfide concentration, and a high water density gradient, which was responsible for stable stratification and contributed to the accumulation of the cells in a narrow layer. The data obtained could be useful for the paleoreconstruction of climatically deter-mined changes in the level of the lake and its periods of meromixis by the presence of carotenoids and bacte-riochlorophylls in the bottom sediments. В© 2012 Pleiades Publishing, Ltd.
Scopus
Найти похожие
13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Adamovich V.V., Rogozin D.Yu., Degermendzhi A.G.
Заглавие : Developing the control criterion for a continuous culture of microorganisms
Место публикации : Mikrobiologiya. - 2005. - Vol. 74, Is. 1. - С. 5-16. - ISSN 00263656 (ISSN)
Ключевые слова (''Своб.индексиров.''): chemostat--control criterion--control factor--microorganism population--sensitivity coefficients--algorithm--bacterium--biological model--biomass--culture medium--ecosystem--growth, development and aging--methodology--microbiological examination--review--algorithms--bacteria--bacteriological techniques--biomass--culture media--ecosystem--models, biological
Аннотация: A short survey and critical analysis of previously proposed criteria for growth control of populations of microorganisms in the chemostat are presented. Based on the analysis of a mathematical model of the steady-state of a microbial population in the chemostat, an adequate control criterion is suggested, along with a method to identify the corresponding regulating factors. The new control criterion is expressed as a product of the factor transformation coefficient and the biomass sensitivity coefficient (SC) with respect to the change of the factor at the chemostat inlet (referred to in the sequel as the biomass SC). The control criterion determines the strength of the control exerted by this or that factor. The method of determination of the regulating factors consists in experimental determination of the real SCs for factors and the biomass and in calculating on this basis the corresponding ideal SCs for constant factor transformation coefficients. The ideal SCs are shown to add up to an integer value, a constraint that we call "quantization" relationships. Such relationships are used to test the completeness of the drawn list of control factors. The proposed method was applied to our own and literature data.
Scopus
Найти похожие
14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Adamovich V.V., Rogozin D.Yu., Degermendzhi A.G.
Заглавие : Developing the control criterion for a continuous culture of microorganisms
Место публикации : Microbiology. - 2005. - Vol. 74, Is. 1. - С. 1-11. - ISSN 00262617 (ISSN) , DOI 10.1007/s11021-005-0021-z
Ключевые слова (''Своб.индексиров.''): chemostat--control criterion--control factor--microorganism population--sensitivity coefficients
Аннотация: A short survey and a critical analysis of previously proposed criteria for growth control of populations of microorganisms in the chemostat are presented. Based on the analysis of a mathematical model of the steady state of a microbial population in the chemostat, an adequate control criterion is suggested, along with a method to identify the corresponding control factors. The new control criterion is expressed as a product of the factor transformation coefficient and the sensitivity coefficient (SC) of the biomass with respect to the change in the factor at the chemostat inlet (hereinafter, the biomass SC). The control criterion determines the strength of the control exerted by a factor. The method of determining control factors consists in experimental determination of the real SCs for factors and the biomass and calculation on this basis of the corresponding ideal SCs, assuming constant factor transformation coefficients. The ideal SCs are shown to add up to integer values, a constraint that we call quantization relationships. Such relationships are used to test the completeness of the list of control factors. The proposed method was applied to both our own and literature data. В© 2005 Pleiades Publishing, Inc.
Scopus
Найти похожие
15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bolsunovskij A.Ya., Zotina T.A., Bondareva L.G., Degermendzhi A.G.
Заглавие : An estimate of 241Am accumulation by the macrophyte Elodea Canadensis
Место публикации : Doklady Akademii Nauk. - 2004. - Vol. 399, Is. 1. - С. 130-133. - ISSN 08695652 (ISSN)
Ключевые слова (''Своб.индексиров.''): biomass--fractionation--minerals--organic compounds--plants (botany)--radioactivity--radioisotopes--accumulation--macrophytes--americium
Аннотация: The lab experiments showed that specific activity of 241Am achieves 3280В±240 Bc/g with 241Am accumulation coefficient = 16600В±2200 l/kg. The chemical fractionation results confirmed that 241Am can be strongly fixed by elodea biomass. At the end of long-term experiment the part of 241Am strongly bonded by the biomass reached 27% of total 241Am content in biomass. The accumulation process proceeds with 241Am redistribution towards decreasing of the part of exchange and adsorbed fractions and increasing of the part of organic and mineral fractions. Thus, the 241Am part in organic fractions doubled during the experiment and in mineral fraction - grew more than 10 times as compared with initial 241Am distribution.
Scopus
Найти похожие
16.

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).
Scopus
Найти похожие
17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Prokopkin I.G., Mooij W.M., Janse J.H., Degermendzhy A.G.
Заглавие : A general one-dimensional vertical ecosystem model of Lake Shira (Russia, Khakasia): Description, parametrization and analysis
Место публикации : Aquatic Ecology. - 2010. - Vol. 44, Is. 3. - С. 585-618. - ISSN 13862588 (ISSN) , DOI 10.1007/s10452-010-9326-8
Ключевые слова (''Своб.индексиров.''): meromictic brackish lake--one-dimensional vertical ecological model--sensitivity analysis--alga--biomass--brackish water--diffusion--ecosystem modeling--meromictic lake--microbial community--model test--nutrient--one-dimensional modeling--parameterization--phytoplankton--seasonality--sensitivity analysis--solar radiation--vertical profile--water chemistry--water temperature--zooplankton--khakassia--lake shira--russian federation--algae
Аннотация: A one-dimensional ecological model of the meromictic brackish Lake Shira (Russia, Khakasia) was developed. The model incorporates state-of-the-art knowledge about the functioning of the lake ecosystem using the most recent field observations and ideas from PCLake, a general ecosystem model of shallow freshwater lakes. The model of Lake Shira presented here takes into account the vertical dynamics of biomasses of the main species of algae, zooplankton and microbial community, as well as the dynamics of oxygen, detritus, nutrients and hydrogen sulphide from spring to autumn. Solar radiation, temperature and diffusion are modelled using real meteorological data. The parameters of the model were calibrated to the field data, after applying different methods of sensitivity analysis to the model. The resulting patterns of phytoplankton and nutrients dynamics show a good qualitative and quantitative agreement with the field observations during the whole summer season. Results are less satisfactory with respect to the vertical distribution of zooplankton biomass. We hypothesize that this is due to the fact that the current model does not take the sex and age structure of zooplankton into account. The dynamics of oxygen, hydrogen sulphide and the modelled positions of the chemocline and thermocline are again in good agreement with field data. This resemblance confirms the validity of the approach we took in the model regarding the main physical, chemical and ecological processes. This general model opens the way for checking various hypotheses on the functioning of the Lake Shira ecosystem in future investigations and for analysing options for management of this economically important lake. В© 2010 Springer Science+Business Media B.V.
Scopus
Найти похожие
18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Rogozin D.Y., Zykov V.V., Chernetsky M.Y., Degermendzhy A.G., Gulati R.D.
Заглавие : Effect of winter conditions on distributions of anoxic phototrophic bacteria in two meromictic lakes in Siberia, Russia
Место публикации : Aquatic Ecology. - 2009. - Vol. 43, Is. 3. - С. 661-672. - ISSN 13862588 (ISSN) , DOI 10.1007/s10452-009-9270-7
Ключевые слова (''Своб.индексиров.''): chemocline--green sulphur bacteria--purple sulphur bacteria--snow--winter--anoxic conditions--bacterium--biomass--ice cover--light intensity--meromictic lake--photoautotrophy--remote sensing--vertical distribution--eurasia--khakassia--lake shira--lake shunet--russian federation--siberia--bacteria (microorganisms)--photobacteria
Аннотация: The year-to-year variations of vertical distribution and biomass of anoxic phototrophic bacteria were studied during ice periods 2003-2005 and 2007-2008 in meromictic lakes Shira and Shunet (Southern Siberia, Russian Federation). The bacterial layers in chemocline of both lakes were sampled with a thin-layer hydraulic multi-syringe sampler. In winter, biomass of purple sulphur bacteria varied considerably depending on the amount of light penetrating into the chemocline through the ice and snow cover. In relatively weakly stratified, brackish Shira Lake, the depth of chemocline varied between winters, so that light intensity for purple sulphur bacteria inhabiting this zone differed. In Shira Lake, increased transparency of mixolimnion in winter, high chemocline position and absence of snow resulted in light intensity and biomass of purple sulphur bacteria exceeding the summer values in the chemocline of the lake. We could monitor snow cover at the lake surface using remote sensing and therefore estimate dynamics and amount of light under ice and its availability for phototrophic organisms. In Shunet Lake, the light intensities in the chemocline and biomasses of purple sulphur bacteria were always lower in winter than in summer, but the biomasses of green sulphur bacteria were similar. В© Springer Science+Business Media B.V. 2009.
Scopus
Найти похожие
19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zotina T.A., Kalachova G.S., Bolsunovsky A.Ya., Degermendzhy A.G.
Заглавие : 241Am distribution in the biomass of freshwater macrophytes
Место публикации : Doklady Biological Sciences. - 2008. - Vol. 421, Is. 1. - С. 254-256. - ISSN 00124966 (ISSN) , DOI 10.1134/S0012496608040108
Ключевые слова (''Своб.индексиров.''): americium--carbohydrate--cellulose--lipid--nitrogen--polysaccharide--vegetable protein--article--biomass--bryopsida--cell membrane--cell wall--chemistry--cytoplasm--food chain--growth, development and aging--hydrocharitaceae--metabolism--americium--biomass--bryopsida--carbohydrates--cell membrane--cell wall--cellulose--cytoplasm--food chain--hydrocharitaceae--lipids--nitrogen--plant proteins--polysaccharides
Scopus
Найти похожие
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.
Scopus
Найти похожие
 1-20    21-40   41-60   61-80   81-100   101-120      
 

Другие библиотеки

© Международная Ассоциация пользователей и разработчиков электронных библиотек и новых информационных технологий
(Ассоциация ЭБНИТ)