We found that methionine added to the ration of pregnant rats (1 g/kg body weight) induced sustained hyperhomocysteinemia and led to the formation of sustained oxidative stress in the brain of their progeny. Newborn animals were characterized by lower body weight, SOD deficiency in the brain, increased neuronal death, and desensitization of NMDA receptors. These factors are associated with impaired cognitive capacity in the Morris test.

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Acoustic radiation emitted by three-dimensional (3D) vortex rings in air has been investigated on the basis of the unsteady Navier-Stokes equations. Power series expansions of the unknown functions with respect to the initial vorticity which is supposed to be small are used. In such a manner the system of the Navier-Stokes equations is reduced to a parabolic system with constant coefficients at high derivatives. The initial value problem is as follows. The vorticity is defined inside a toroid at t = 0. Other gas parameters are assumed to be constant throughout the whole space at t = 0. The solution is expressed by multiple integrals which are evaluated with the aid of the Korobov grids. Density oscillations are analyzed. The results show that the frequency band depends on the initial size of the vortex ring and its helicity. The presented data may be applied to the study of a flow in a wake region behind an aerodynamic body.

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