Direct Verification of the Kinetic Description of Wave Turbulence for Finite-Size Systems Dominated by Interactions among Groups of Six Waves.

The present work considers systems whose dynamics are governed by the nonlinear interactions among groups of 6 nonlinear waves, such as those described by the unforced quintic nonlinear Schrödinger equation. Specific parameter regimes in which ensemble-averaged dynamics of such systems with finite size are accurately described by a wave kinetic equation, as used in wave turbulence theory, are theoretically predicted. In addition, the underlying reasons that the wave kinetic equation may be a poor predictor of wave dynamics outside these regimes are also discussed. These theoretical predictions are directly verified by comparing ensemble averages of solutions to the dynamical equation with corresponding solutions of the wave kinetic equation.

Simultaneous numerical simulation of direct and inverse cascades in wave turbulence.

The results of the direct numerical simulation of isotropic turbulence of surface gravity waves in the framework of Hamiltonian equations are presented. For the first time, the simultaneous formation of both direct and inverse cascades has been observed in the framework of the primordial dynamical equations. At the same time, a strong long wave background has been developed. It has been shown that the Kolmogorov spectra obtained are very sensitive to the presence of this condensate. Such a situation has to be typical for experimental wave tanks, flumes, and small lakes.

Coexistence of weak and strong wave turbulence in a swell propagation.

By performing two parallel numerical experiments-solving the dynamical Hamiltonian equations and solving the Hasselmann kinetic equation-we examined the applicability of the theory of weak turbulence to the description of the time evolution of an ensemble of free surface waves (a swell) on deep water. We observed qualitative coincidence of the results. To achieve quantitative coincidence, we augmented the kinetic equation by an empirical dissipation term modeling the strongly nonlinear process of white capping. Fitting the two experiments, we determined the dissipation function due to wave breaking and found that it depends very sharply on the parameter of nonlinearity (the surface steepness). The onset of white capping can be compared to a second-order phase transition. The results corroborate the experimental observations of Banner, Babanin, and Young.

Weak turbulent Kolmogorov spectrum for surface gravity waves.

We study the long-time evolution of surface gravity waves on deep water excited by a stochastic external force concentrated in moderately small wave numbers. We numerically implemented the primitive Euler equations for the potential flow of an ideal fluid with free surface written in Hamiltonian canonical variables, using the expansion of the Hamiltonian in powers of nonlinearity of terms up to fourth order. We show that because of nonlinear interaction processes a stationary Fourier spectrum of a surface elevation close to <|eta(k)|(2)> approximately k(-7/2) is formed. The observed spectrum can be interpreted as a weak-turbulent Kolmogorov spectrum for a direct cascade of energy.

[Reaction of the blood forming system of the dogs to acute radiation exposure (by the SRC-Institute of biophysics data bank)]. / Reaktsiia krovetvornoi sistemy sobak na ostroe radiatsionnoe vozdeistvie (po materialam bazy dannykh GNTS-Institut biofiziki MZ RF).

At present time in the SRC--Institute of Biophysics the data bank containing the information on the reactions of 431 dogs to radiation exposure in a wide range of doses has been created. By the results of 4299 blood tests reporting a leukocyte content, including 2509 tests reporting a blood formula, the individual peculiarity of the peripheral blood reaction in dogs were analyzed. Dose dependencies for the reaction of blood-forming system to radiation exposure to doses in the range from 1.0 to 7.0 Gy were obtained. In comparison with the similar data for humans, the neutrophil content in peripheral blood decreased approximately 1.5-2.0 times faster in dogs than in men, resulting in earlier recovery.

[Prediction of the severity of damage and disruption of work ability in reaction of the body to alcohol load prior to radiation exposure in the superlethal range]. / Prognozirovanie tiazhesti porazheniia i narushenii rabotosposobnosti po reaktsiii organizma na alkogol'nuiu nagruzku do luchevogo vozdeistviia v sverkhletal'nykh dozakh.

In experiments on 121 white non-linear rats, 44 Papio hamadryas and 29 Macaca fascicularis, animals' reactions on the alcohol impact (AI) and following exposure to supralethal doses were compared. The animals were intravenously injected with 5% ethanol in the glucose solution, 2.1 g/kg for rats and 0.46-0.51 g/kg for monkeys. Monkeys' response to AI was scored in four-point scale by estimating of abnormalities in motor activity, coordination of motion and changes in conditioned reflex activity. It was shown that changes in the ability of alcohol-injected rats to perform the learnt exercises in the "jump box" could be used for prediction of their response to the exposure to supralethal doses of ionizing radiation. Observing the AI-response in monkeys along with a method "function of spying for moving object" made possible to predict not only a general degree of loss of working ability but also to estimate individual impairments of spying functions. In 65% monkeys high similarity of the reactions to AI and ionizing radiation was observed.

[A possibility to predict the severity of individual damage following the exposure to supralethal radiation dosage. Prediction by early radiation response ]. / Vozmozhnosti prognozirovaniia individual'noi tiazhesti porazheniia pri luchevykh vozdeistviiakh v sverkhletal'nykh dozakh. Prognozirovanie po rannei reaktsii na obluchenie.

The experiments on dogs and monkeys have shown that the severity of radiation sickness following the exposure to supralethal radiation doses can be predicted by early response of an individual. For such prediction, the most informative criteria include general severity of clinical manifestations during primary radiation response and evaluated within a few post-damage hours, the degree of tension in cardiac rhythm control, the cortisol level, the endocrine status index.

[A possibility to predict the severity of individual damage following the exposure to supralethal radiation dosage. Prediction of working capacity of irradiated rats and dogs by response to pre-exposure physical load]. / Vozmozhnosti prognozirovaniia individual'noi tiazhesti porazheniia pri luchevykh vozdeistviiakh v sverkhletal'nykh dozakh. Prognozirovanie urovnia rabotosposobnosti u obluchennykh krys i sobak po ikh reaktsii na fizicheskuiu nagruzku do oblucheniia.

The experiments on rats and dogs exposed to radiation doses which cause intestinal and cerebral forms of radiation sickness have shown that, within the first 24 hours post-exposure, efficiency impairment can be predicted by changes in some indices of the cardiovascular and endocrine systems after physical load used as a non-radiation testing agent. The goodness of fit of experimental data to the expected result is up to 50-70%, still rising if a number of indices for different sections of the neuroendocrine system are used at a time.

[A possibility to predict the severity of individual damage following the exposure to supralethal radiation dosage. Prediction of the clinical manifestation of radiation injury in laboratory animals by response to pre-exposure hypobaric hypoxia]. / Vozmozhnosti prognozirovaniia individual'noi tiazhesti porazheniia pri luchevykh vozdeistviiakh v sverkhletal'nykh dozakh. Prognozirovanie klinicheskikh proiavlenii luchevoi bolezni u laboratornykh zhivotnykh po ikh reaktsii na gipobaricheskuiu gipoksiiu do oblucheniia.

The experiments on rats, dogs and monkeys exposed to radiation doses which cause intestinal and cerebral forms of radiation sickness have shown that the severity of a clinical state can be predicted by cardiovascular and endocrine changes when a pre-exposure test with moderate hypobaric hypoxia is performed. The goodness of fit of experimental data to the exposed result is up to 60-80%, still rising if a set of indices of the neuroendocrine status is used.

[A possibility to predict the severity of individual damage following the exposure to supralethal radiation dosage. Prediction of working capacity of irradiated rats and dogs by response to pre-exposure hypobaric load]. / Vozmozhnosti prognozirovaniia individual'noi tiazhesti porazheniia pri luchevykh vozdeistviiakh v sverkhletal'nykh dozakh. Prognozirovanie urovnia rabotosposobnosti obluchennykh krys i sobak po ikh reaktsii na gipobaricheskuiu nagruzku do oblucheniia.

In experiments on rats and dogs exposed to radiation doses which cause intestinal and cerebral forms of radiation sickness, hypobaric hypoxia used as an unconventional test of animals' reactivity has enabled the relationship between reactivity and radiosensitivity to be established. Higher post-radiation efficiency is observed in animals with less pronounced changes during a barotest. The goodness of fit of experimental data to the expected result is up to 70%, rising if a set parameters for one index or the sum total of indices are used.

[Quantitative regularities for clinical manifestations of radiation injury in large-sized laboratory animals exposed to supralethal radiation doses Gamma-neutron and electron biological effectiveness as influenced by exposure conditions and dose distribution in the animal body]. / Kolichestvennye zakonomernosti klinicheskikh proiavlenii luchevoi bolezni u krupnykh laboratornykh zhivotnykh pri vozdeistvii izlucheniia v sverkhletal'nykh dozakh Vliianie uslovii oblucheniia i raspredeleniia doz po telu zhivotnykhna biologicheskuiu éffektivnost' gamma-neitronnogo i élektronnogo izlucheniia.

The damaging effect of gamma-neutron radiation over a wide neutron-energy range, with average values of 0.37 and 1.2 MeV, and that of electrons with an average electron energy of 25 MeV have been compared in dogs and two monkey species exposed to a broad range of supralethal doses. An analysis of absorbed dose distribution in critical organs and systems has shown the highest effect of gamma-neutron radiation with an average neutron energy of 1.2 MeV. With severity of early clinical manifestations of damage as a criterion, electrons have appeared the most effective. The radiosensitivity of animals grew in the order as follows: dog-->M. fascicularis-->P. hamadryas.

[Estimation of the individual radioresistance based on various parameters of the initial state of the body regulatory systems in animals]. / Otsenka individual'noi radioustoichivosti zhivotnykh na osnove nekotorykh pokazatelei iskhodnogo sostoianiia reguliatornykh sistem organizma.

The possibility of predicting the individual radiosensitivity of rats with the aid of a logarithmic index, which characterizes the initial state and quality of regulatory systems, is demonstrated. The index is calculated on the basis of some parameters of endocrine status before irradiation, such as corticosterone concentration and the ratio of potassium and sodium ions in the blood of experimental animals.

[Dynamics of the non-specific reactivity of the organism in time]. / Dinamika proiavlanii nespetsificheskoi reaktivnosti organizma vo vremeni.

Experiments with 10 mongrel rats and dogs showed that individual reactivity of animals to hypobaric hypoxia was same during repeated exposure in two weeks. Investigations of 20 dogs demonstrated relatively permanent types of group reactivity, i.e. hyper-, normal, and hyporeactivity to adrenaline injections every 2 months over a year period. Each type of group reactivity was marked by phase variation in the count of peripheral blood leukocytes with the relation of group mean values unchanged. Analysis of mean values of adaptive levels in 340 subjects with varying individual reactivity over 10 years also pointed to undulation of these values in each group. At the same time, the difference in mean values of this parameter among the groups was kept constant. Hence, the group specific reactivity has a long-range character as determined by testing.

[Individual radioresistance and principles of its formation]. / Individual'naia radiorezistentnost' i printsipy ee formirovaniia.

Individual variability of resistance to a broad range of ionizing radiation was analyzed. Individual radioresistance depends both on physical (radiation type, dose, and distribution along the body, dose rate) and biological (species, strain, sex, body mass of animal etc.) factors. Individual radioresistance is manifested by specific and nonspecific responses of organism to radiation. Three components of individual radioresistance are stable, semistable and labile. The stable component is genetically determined by species, sex, habitus status and radiosensitivity of cells of critical organs. The semistable component is determined by embryogenetic, early postnatal development and reflected in functional activity of the main regulatory systems of the body. The labile component is a parameter of current functional state of an indviduum. The stable and semistable components characterize inborn whereas the labile component--acquired radioresistance.

[Quantitative characteristics of radiation sickness clinical manifestations in large-sized laboratory animals exposed to extra-lethal radiation doses. The endocrine system reactions in dogs and monkeys]. / Kolichestvennye zakonomernosti klinicheskikh proiablenii luchevoi bolezni u krupnykh laboratornykh zhivotnykh pri vozdeistvii izlucheniia v sverkhletal'nykh dozakh. Reaktsiia éndokrinnoi sistemy sobak i obez'ian.

The dynamics of cortisol, insulin and triiodothyronine content of the blood has been studied in dogs and two monkey species exposed to electron and gamma-neutron radiations in a wide supralethal--dose range. A calculated value--index of the endocrine status--has been used for integral estimation the function of the endocrine system. A considerable disintegration of the functions of separate endocrine glands has been observed, which correlates with degree of clinical manifestations in animals and radiation dose.

[Quantitative patterns in the clinical manifestations of radiation sickness in large laboratory animals exposed to radiation at superlethal doses. The quantitative patterns in the manifestations of radiation sickness in dogs]. / Kolichestvennye zakonomernosti klinicheskikh proiavlenii luchevoi bolezni u krupnykh laboratornykh zhivotnykh pri vozdeistvii izlucheniia v sverkhletal'nykh dozakh. Kolichestvennye zakonomernosti proiavlenii luchevoi bolezni u sobak.

Radiation sickness manifestations have been studied in dogs exposed to electrons (electron energy 25 MeV) and gamma-neutron radiation (neutron energies of 0.37 and 1.2 MeV) in a wide dose range. Dose-response relationships have been calculated for mortality and some clinical manifestations of the intestinal and cerebral forms of radiation sickness. With regard to mortality, the highest effect has been observed for gamma-neutron radiation with a neutron energy of 1.2 MeV. For equal physical doses and for those equally effective in relation to mortality, clinical manifestations of damage are more prominent following exposure to electrons.

[Quantitative patterns in the clinical manifestations of radiation sickness in large laboratory animals exposed to radiation at superlethal doses. The quantitative patterns in the manifestations of radiation sickness in monkeys]. / Kolichestvennye zakonomernosti klinicheskikh proiavlenii luchevoi bolezni u krupnykh laboratornykh zhivotnykh pri vozdeistvii izlucheniia v sverkhletal'nykh dozakh. Kolichestvennye zakonomernosti proiavlenii luchevoi bolezni u obez'ian.

Radiation sickness manifestations have been studied in two species (Macaca fascicularis and Papio hamadryas) exposed to electron and gamma-neutron radiations in a wide supralethal doses range. Dose-response relationships have been calculated for mortality and some clinical manifestations of the intestinal and cerebral forms of radiation sickness. Higher radiosensitivity of baboons in comparison with Macaca fascicularis and clinically more dangerous damage due to electrons as compared to gamma-neutron radiation have been demonstrated.

[Quantitative patterns in the clinical manifestations of radiation sickness in large laboratory animals exposed to radiation at superlethal doses. Changes in the regulation of cardiovascular system function]. / Kolichestvennye zakonomernosti klinicheskikh proiavlenii luchevoi bolezni u krupnykh laboratornykh zhivotnykh pri vozdeistvii izlucheniia v sverkhletal'nykh dozakh. Izmeneniia v reguliatsii funktsii serdechno-sosudistoi sistemy.

Dog exposure to doses from 39 to 124 Gy results in an increase of heart rate and tension in control of the cardiac rhythm, the extent being dose dependent. An additional physical load on the cardiovascular animals system reveals a high functional control reserves of the cardiovascular system which provides stable functioning even after exposure to the above doses.

[Changes in the dog endocrine system in the hematopoietic form of radiation sickness]. / Izmeneniia v éndokrinnoi sisteme sobak pri krovetvornoi forme luchevoi bolezni.

The endocrine status of the organism estimated by the cortisol, insulin and triiodothyronine content of blood considerably changes during radiation sickness. The most pronounced changes in the endocrine status occur during the primary response and at the height of radiation sickness. The endocrine status test may be used in the individual radiosensitivity prognosis.