Deformation behavior of a human dentin under compression including size and rate effects is studied. No difference between mechanical properties of crown and root dentin is found. It is mechanically isotropic high elastic and strong hard tissue, which demonstrates considerable plasticity and ability to suppress a crack growth. Mechanical properties of dentin depend on a shape of samples and a deformation rate.

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The objective of this paper is the proof of a conjecture of Kontsevich [1] on the isomorphism between groups of polynomial symplectomorphisms and automorphisms of the corresponding Weyl algebra in characteristic zero. The proof is based on the study of topological properties of automorphism Ind-varieties of the so-called augmented and skew augmented versions of Poisson and Weyl algebras. Approximation by tame automorphisms as well as a certain singularity analysis procedure is utilized in the construction of the lifting of augmented polynomial symplectomorphisms, after which specialization of the augmentation parameter is performed in order to obtain the main result.

Abstract-The influence of liquid on the mechanical properties of human dentin under uniaxial compression is studied in this work. It has been shown that the storage of samples for 24 h in water, acetone, and glycerin does not lead to a change in the microstructure or to qualitative changes in the mechanical behavior of dentin, which continues to be highly elastic; capable of considerable plastic deformation; and a strong, hard tissue.

The present article deals with morphological comparison of four species of shrimp larvae, such as Neocrangon communis and Mesocrangon intermedia, Crangon dalli and C. septemspinosa, inhabiting the Okhotsk Sea and north-western part of the Pacific Ocean. Morphological comparison of I-V zoeal stages is discussed. The main morphological differences of the appropriate larval stages are detected. Most features of C. dalli and C. septemspinosa are similar and differ from M. intermedia and N. communis. It is shown that M. intermedia and N. communis more similar species by their origin than it is accepted to think. It is assumed that these two species should be included into one genus-Mesocrangon. The figures of I, III-V zoeal stages are presented.