Silver nanoparticles possess antibacterial effect for various bacteria; however mechanisms of the interaction between Ag-NPs and bacterial cells remain unclear. The aim of our study was to obtain direct evidence of Ag-NPs penetration into cells of Gram-negative bacterium S. typhimurium and Gram-positive bacterium S. aureus, and to study cell responses to Ag-NPs. The Ag-NPs (most 8-10 nm) were obtained by gas-jet method. S. typhimurium (7.81 × 10⁷ CFU), or S. aureus (8.96 × 10⁷ CFU) were treated by Ag-NPs (0.05 mg/l of silver) in orbital shaker at 190 rpm, 37 °C. Bacteria were sampled at 0.5, 1, 1.5, 2, 5 and 23 h of the incubation for transmission electron microscopy of ultrathin sections. The Ag-NPs adsorbed on outer membrane of S. typhimurium and cell wall of S. auereus; penetrated and accumulated in cells without aggregation and damaging of neighboring cytoplasm. In cells of S. aureus Ag-NPs bound with DNA fibers. Cell responses to Ag-NPs differed morphologically in S. typhimurium and S. aureus, and mainly were presented by damage of cell structures. The cytoplasm of S. aureus became amorphous, while S. typhimurium showed lumping and lysis of cytoplasm which led to formation of "empty" cells. Other difference was fast change of cell shape in S. typhimurium, and late deformation of S. aureus cells. The obtained results showed how different could be responses induced by the same NPs in relatively simple prokaryotic cells. Evidently, Ag-NPs directly interact with macromolecular structures of living cells and are exert an active influence on their metabolism.

Drawing on a dataset consisting of 344 personal interviews, participant observations, and internal documents collected in 26 privately owned business organizations in Russia, the study aims at complementing existing research on Russian indigenous management in three ways. First, it examines the managerial styles of key individuals (i.e. owners and/or CEOs) in the case organizations. Hence, it taps into the existing heterogeneity of managerial styles, the so-called groupvergence, found in contemporary Russian organizations, and documents their idiosyncratic features, such as the transformational nature of authoritarian leadership. Second, the study explores the antecedents of the identified styles to establish what factors contribute to their emergence and thus sheds light on how the heterogeneous managerial styles in Russian organizations come into existence. Finally, the study investigates how the identified styles manifest themselves in organizations by influencing organizational goals and strategies, organizational structures, supporting mechanisms, relationships between organizational members, and reward systems. It therefore elaborates on the organizational implications of the styles and highlights the mechanisms of their sustainable diffusion to lower organizational levels in Russian organizations.

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The interest in jets expanding into a vacuum or a low-density background is raised by the appearance of new technological methods and growing requirements of high technology development. The use of free jets for vacuum technology, including space applications, has a number of aspects. One of the important achievements of the previous investigations is an understanding of jet structures in a variety of gas dynamic conditions. The accumulated knowledge on radial expansion into a vacuum, on the expansion of jets behind axially symmetric and flat sonic, and supersonic nozzles into a vacuum and background from the literature can be used for approximate evaluations. At present, more detailed data can be obtained as the result of computational modeling by continuum and kinetic approaches. Modern gas dynamics has at its disposal effective theoretical methods that open wide possibilities for vacuum technology development. The present article reflects the accumulated knowledge on the structure of jets, calculation of jet parameters, and modern trends in the analysis of low density jets.