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Molecular dynamics method and finite element analysis are applied for the analysis of the stress field in the neighborhood of the crack tip in a copper plate with a single edge notch. The molecular dynamics simulations implemented in a classical molecular dynamics code LAMMPS (Large-scale Atomic/Molecular Massively Parallel Simulator) are aimed at evaluating classical continuum linear elastic fracture mechanics parameters such as stress intensity factors, T-stresses and higher order coefficients of the Williams power series expansion of the near crack stress field for Mode I, Mode II and Mixed Mode (Mode I + Mode II) loadings of the cracked specimen in isotropic linear elastic materials. The key objective of the study is the comparison of continuum and atomistic approaches for the estimation of the near crack tip fields using the example of one of the most common cracked configurations. Stress intensity factors, T-stresses and higher order coefficients of the Williams series expansion for a copper plate with the single edge notch under Mode I and Mixed Mode loadings are evaluated by atomistic modeling and by finite element method. The wide class of the computations in LAMMPS is performed. The atomistic values of stress intensity factors and higher order terms of the Williams series expansion are compared with the values obtained from the numerical solutions given by finite element method. It is shown that the continuum fracture theory successfully describes fracture and the near crack tip fields even at extremely confined singular stress field of only several nanometers. The angular distributions of the stress components from atomistic modeling are retrieved and compared with the angular distributions of the stresses from continuum linear elastic fracture mechanics. The comparison shows good agreement between two approaches. [ABSTRACT FROM AUTHOR]

Data on the contents of protein, fats and toxic compounds (PCB, DDT, gamma-Lindane) in breast milk Russian and Vietnamese women after timely and premature childbed are resulted. The contents of protein in transitive milk was higher than in mature milk, both timely childbed and premature one. The contents of protein in nature milk of the Vietnamese women was lower, than in mature milk of the Russian women (12 g/l against 16.5 g/l accordingly). The contents of fat in breast milk of the Russian women in lactation increased. Vietnamese women had very low fat level in mature milk (29 g/l against 42 g/l at the Russian women). The contents of toxic compounds (PCB, DDT, gamma-Lindane) in breast milk both, Vietnamese women and Russian women was rather high and significant frequency of detection of these compounds in milk was marked. The correlation contents of basic food components in breast milk and level of toxic compounds was absent.

The results of the cooperated clinical trial of sulacillin, a formulation including sodium ampicillin and sulbactam (2:1), are presented. The trial was carried out in different hospitals of Moscow and Smolensk. Rapid development of the favourable time course and recovery were stated in 93.7 per cent of the cases with upper and lower respiratory tract infections, urinary and biliferous tract infections, infections of the skin and soft tissues, gynecological infections and severe suppurative complications after surgical operations. Sulacillin is useful in the empirical therapy of purulent inflammatory diseases before the pathogen isolation and identification.

Altogether 57 premature infants were examined. Of these, 15 presented with neonatal sepsis, 36 with local purulent infection (LPI) of different etiology, and 6 children were conventionally normal serving as control. Early activation of the alternative pathway of the complement system was shown by the patients as compared with control. The development of neonatal sepsis was attended by the increased role played by the classical pathway of complement activation. At the same time the course of LPI was characterized by differences in the degree of participation of the classical and alternative pathways in the antiinfectious defence of the neonates. It has been established that high activation of the alternative pathway seen in the premature children may be considered as a prognostic sign enabling one to classify them with the risk group in terms of the possibility of the development in them of an infectious process.