An underwater survey was conducted in the Louvenga River to investigate the behaviour and distribution of juvenile Atlantic salmon, Salmo salar L., and the adaptation of cultured fish to the natural environment. The food and feeding habits of 34 wild and 44 cultured parr released from the Kandalaksha hatchery were also studied. The cultured salmon fed mostly in the bottom 15 cm of the water column in current velocities of 0.2e0.35 m s À1 . In contrast to wild fish, when cultured fish moved away from these areas and into areas with higher current velocities (average speeds of 0.52 m s À1 ) and lower drift density (2.66 particles m À3 ), they did not show a tendency to return to slower moving water. The diet of cultured parr was made up of benthic invertebrates (20%), terrestrial insects (32%), and drift items (33%), but these proportions were different in the diet of wild parr (2%, 24%, and 67%, respectively), with drift items predominating. The mean quantity of food per stomach indicated that the wild parr were feeding more actively than cultured parr. Invertebrates made up 3% of items in the drift, with the remaining 97% being exuvia of aquatic and terrestrial insects, algae, and various plant remains. Poor quality food items were found in 13% and 25% of the stomachs of wild and cultured parr, respectively, demonstrating that the cultured parr were less able to differentiate food items in the water column and made 20e30% more false feeding attempts than wild fish. The cultured parr were also more aggressive in terms of the frequency of aggressive interactions and reacted to each other at greater distances than wild fish. Thus, wild parr were able to optimize their feeding conditions by choosing habitats with preferred sizes of food items, higher densities of drift items, and current velocities that allowed them to maintain station and to feed more effectively. Conversely, cultured parr usually occupied suboptimal areas.

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Half of obese Russian inhabitants are metabolically healthy. At the same time, metabolic abnormalities were detected in one third of non-obese participants with a shift to male gender.

Application of the artificial clouds of charged water aerosol capable to initiate discharges inside clouds and between cloud and ground could help on the solving of problem of separation of the lightning intracloud and ground discharges, and establishment of connections between the parameters and the spectral characteristics of discharge current impulses and its electromagnetic radiation. Results of analysis of spectral characteristics of discharge from artificial thundercloud and radiation created by them in near field using two kinds of wavelets are presented. Characteristics frequency ranges for different stages of discharge formation and its radiation are analyzed. Comparison between the discharge current parameters and the parameters of its electromagnetic radiation and wavelet characteristic frequencies has been fulfilled. Application of received results to the analysis of electromagnetic radiation signals registered during the different stages of lightning is discussed.

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