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1.
Dolmatova L. S. Eliseykina M. G. Timchenko N. F. Kovaleva A. L. Shitkova O. A. 《中国海洋湖沼学报》2003,21(4):293-304
Pure fraction (92%–95%) of phagocytes (FP) and a mixture of amoebocytes (62%) and morula cells (38%)-FPMC- of the holothurianEupentacta fraudatrix' (Holothuroidea, Dendrochirota) were obtained by using ficoll-verographine step gradient. Basal production of reactive oxygen species (ROS) in FP quantified
by using reduction of nitroblue tetrazolium (NBT) was more than twice that in FPMC. Thermostable toxin ofYersinia pseudotuberculosis (TST) at different concentrations (0.2; 0.5; 2.5 μg/ml, but not 0.1 μg/ml) stimulated NBT reduction in FPMC after 24 h incubation.
In FP, TST at concentrations of 0.1 and 0.2 μg/ml inhibited and at concentrations of 0.5 and 2.5 μg/ml stimulated NBT reduction
after 24 h incubation. Maximal effect was observed in FP and FPMC at TST concentrations of 0.5 and 0.2 μg/ml, respectively.
Addition of catalase (0.7 μg/ml) to the cells treated with TST (2.5 μg/ml) was followed by a decrease in NBT reduction compared
to that under toxin treatment alone. TST stimulated superoxide dismutase activity in concentration-dependent manner (maximum
at 0.5 μg/ml concentration in FP) after 24 h treatment, and this stimulation was prevented by a commercial catalase. Plant
lectin concanavalin A stimulated NBT reduction more than 5-fold in FPMC compared to the control. With addition of TST, lectin
stimulated ROS to lesser extent than that with lectin alone. When catalase, TST, and lectin were added into the FPMC simultaneously,
ROS increase was similar to that under lectin treatment alone. On the whole, data obtained indicated that ROS generation in
holothurian coelomocytes especially occurs in both stimulated and not stimulated phagocytes, and that changes in ROS production
by these cells may be one of the mechanisms of antibacterial protection of holothurians.
This work was financially supported by the Russian Foundation for Fundamental Research Grant (No. 00-04-48949). 相似文献
2.
We consider the problem of stable development of natural economical complexes from the viewpoint of basic balances in an ecological
economical system. We construct a basic dynamical model of the complex capable of predicting various scenarios of the industrial
development, consumption of natural resources, and pollution of the environment and propose a mechanism of control over the
process of development by introducing rent payments for the use of natural resources and ecological fines for the pollution
of the environment. The efficiency of the applied model is demonstrated by analysing the process of control over the concentration
of biological resources in marine media as an example. We describe the results of numerical experiments performed to show
the possibility of creation of the information technology of control over marine bioresources.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
3.
We study the processes of global self-regulation of Earth’s biota (GAIA-theory) by applying the method of adaptive balance of causes proposed by the authors. By using, as an example, the Daisy World model constructed by this method, we reveal the phenomenon of preservation of the mean temperature of Earth’s surface due
to the presence of the vegetation cover. We develop an integral model of global natural, social, and economic processes in
which the World Ocean is one of the factors regulating the amount of greenhouse gases in the atmosphere. The decrease in the
amount of greenhouse gases in the atmosphere caused by the GAIA-effects increases the number of hurricanes and floods on the Earth. As a result, the levels of ecological and social hazards
for the mankind become much higher. To eliminate these threats, it is necessary to intensify the processes of self-organization
of the society realized via the improvement of education, development of science, and global regulation of the competition
for natural resources. We present the results of numerical experiments performed by using the model demonstrating possible
scenarios of global development with regard for the processes of self-organization of the society.
__________
Translated From Morskoi Gidrofizicheskii Zhurnal, No. 3, Pp. 62–80, May–June, 2007. 相似文献
4.
The paper considers the application of self-organizing models, specifically, the method of grouped arguments consideration
(MGAC), to forecast short and non-stationary time series of observations in the ocean. A sequence of operations for the treatment
of observational series is suggested. To assess its efficiency, we have used mean monthly oxygen concentration data collected
in the surface and near-bottom layers of the Taganrog Bay. It is shown that the application of the MGAC model allows one to
reduce by two times the root-mean-square error of that of the series prediction by five points, in comparison with the Jenkins-Box
regressional model. It has been concluded that the predictors' non-linear functions may be effectively used in the treatment
of short samplings.
Translated by Vladimir A. Puchkin. 相似文献
5.
I. E. Timchenko V. O. Belozersky S. I. Khlopushina V. A. Benzhitsky 《Physical Oceanography》1989,1(2):111-119
In this paper we compare, two dynamico-stochastic models (DSMs) with different hydrodynamic parts, designed to study a large-scale North Atlantic region. As a performance criterion, RMS errors (over the horizon) in density and velocity field reconstruction are used. It has been shown that in some cases it seems rational to use DSMs with simplified hydrodynamic parts. This helps to expedite the computations and to reduce the related costs without much detriment to the quality of hydrophysical field simulation.UDK 551.465.001.573(261.1).Translated by Vladimir A. Puchkin. 相似文献
6.
The problem of simulation of possible scenarios of the development of processes running in ecological economic systems is studied as a part of the general problem of control over natural economic complexes. The consumption of mineral, food, and ecological resources is regarded as credits given by the society to the producer and then refunded as a part of his gains. If this nature-protective tax does not compensate the damage to the environment caused by production, then the debt of the producer (called accumulated credit) appears and, finally, the process of consumption of the resources is terminated. A universal simulation model is constructed by using a new method of adaptive balance of causes (ABC method). We present basic concepts of this method and some examples of application of the simulation model to the analysis of various scenarios of consumption of marine bioresources under variable economic conditions for a marine environment with variable assimilation capacity. 相似文献
7.
We propose a method for the construction of dynamic-stochastic models of natural systems based on the assimilation of the data of observations in the prognostic equations of coupled processes. In these models, the method of adaptive balance of causes is used to deduce evolutionary equations of the analyzed processes and assimilate the data of observations in these equations. The deduced general equations are considered for an example of a marine ecosystem characterized by the development of four coupled processes. It is shown that the optimal prediction of these processes requires the solution of 11 systems of equations with simultaneous adaptation of prognostic estimates and the coefficients of the models to the data of observations. A numerical simulation experiment explaining the algorithm of the proposed method of modeling is considered. A conclusion is made that the application of this method in the geoinformation systems of monitoring of the environment is quite promising.__________Translated from Morskoi Gidrofizicheskii Zhurnal, No. 6, pp. 31–42, November–December, 2004. 相似文献
8.
The problem of monitoring of the mesoscale variability of hydrophysical fields in the shelf zone is considered. The usefulness of the data available in regional information centres is discussed. The possibility of monitoring the dynamics of the oceanic fields in the tropical Atlantic encompassing separate observation sites is demonstrated using the oceanographic databank of the scientific research centre (CERESCOR) in Conakry-Rogbane as an example. The results of assimilation of the hydrophysical survey data derived on the shelf in a telescopic model of the region are given.Translated by Mikhail M. Trufanov. 相似文献
9.
We present a model of the processes of development in the ecosystem of the coastal zone of the sea constructed by the method
of adaptive balance of causes (ABC-method). The model contains nine variables (phyto- and zooplankton, fish larvae, fishes, oxygen, carbon dioxide, salinity,
biogenic elements, and detritus) affected by the solar radiation, surface wind, sea temperature, and river discharge. The
equations of the model contain control agents governing the dependences of the elements of the food chain on the vitally important
resources and environmental conditions. The scenarios of the processes of development are constructed for the simulated annual
courses of external actions. The possibility of management of fish resources by regulating the flows of biogenic elements
and detritus with river discharge is discussed. A mechanism of management based on the monitoring of the concentration of
dissolved oxygen in seawater is proposed. The numerical experiments show that the ABC-model of the processes of development in the ecosystem of the coastal zone of the sea makes it possible to simulate the scenarios
of regulation of the flows of biogenic elements and detritus into the sea with an aim of preservation of of fish resources.
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 1, pp. 36–49, January–February, 2009. 相似文献
10.
We analyze the statistical structure of the data of remote sensing of the fields of surface temperature and the concentration
of chlorophyll in the northwest part of the Black Sea with an aim to apply the method of optimal interpolation to the restoration
of the maps of these fields according to the restricted amounts of data. We determine the scales of smoothing for the selection
of the random components of the fields and estimate their difference from the statistical model uniform and isotropic over
the space correlation coefficients. The functions of spectral densities are constructed along various sections and the best
intervals of discretization of the fields required to perform the optimal interpolation with given accuracy are determined.
It is shown that the construction of the maps of fields under the conditions of controlled accuracy of reconstruction of their
values remains possible even if the amounts of the input satellite data are significantly decreased. We consider a procedure
of evaluation of the best possible amounts of data required for the use of the method of optimal interpolation. Some examples
of application of this procedure to the data of remote sensing of the fields of surface temperature and the concentration
of chlorophyll are presented. 相似文献