Proper organization of microtubule arrays is essential for intracellular trafficking and cell motility. It is generally assumed that most if not all microtubules in vertebrate somatic cells are formed by the centrosome. Here we demonstrate that a large number of microtubules in untreated human cells originate from the Golgi apparatus in a centrosome-independent manner. Both centrosomal and Golgi-emanating microtubules need gamma-tubulin for nucleation. Additionally, formation of microtubules at the Golgi requires CLASPs, microtubule-binding proteins that selectively coat noncentrosomal microtubule seeds. We show that CLASPs are recruited to the trans-Golgi network (TGN) at the Golgi periphery by the TGN protein GCC185. In sharp contrast to radial centrosomal arrays, microtubules nucleated at the peripheral Golgi compartment are preferentially oriented toward the leading edge in motile cells. We propose that Golgi-emanating microtubules contribute to the asymmetric microtubule networks in polarized cells and support diverse processes including post-Golgi transport to the cell front.

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The article presents the results of experiments on the use dispersed components with reduced stiffness in concrete mixtures to assess their influence on the dynamic strength of concrete. A crushed ceramic bricks, the polystyrene foam, cellular glass and expanded clay sand were used components with reduced stiffness. Samples-cubes were subjected to various dynamic loads, and then measured their strength and were compared with the results obtained for a control sample. Furthermore by vertical dynamic koper were measured impact strength of the obtained compositions. The results of experimental studies are showing the possibility of increasing the impact strength of concrete by introducing into the concrete mix an additive with reduced stiffness. In the same time there is some reduction in other properties of the resulting concrete. Has been defined the optimum additive and its amount to use in the concrete that subjected to dynamic loads.

Abstract. To ensure compliance with historic solutions as the primary binder of dry mixes for the restoration is air lime. To date, almost all of the advantages and disadvantages of the lime-based mortars are known, and this allows implementing a scientific approach to the goal of ensuring the maximum possible durability of masonries and finishing designs. This article covers the main problems and goals faced by professionals in the field of producing dry building mixtures that are the most technologically and economically appropriate for the restoration of the historical buildings and constructions. The use of modern mineral additives opens up new prospects for improving the properties of lime dry mixtures, for both new construction and restoration works of the objects of historical heritage.