No morphological changes in cells indicating changes in

No morphological changes in autotaxin inhibitor indicating changes in their condition, such as nuclear vacuolation, enlargement or segmentation, were observed at prolonged QD incubation. Additionally, no cells were observed to deatech from the substrate (Fig. 3). The effect of the ZnSe:Mn/MPA QDs on the condition of the mononuclear cells (MNCs) isolated from peripheral blood (with an admixture of red blood cells) was assessed in the following way. The material was taken after 18, 24 and 48 h of QD-incubation. No morphological changes in the culture during these times of prolonged incubation with MPA QDs were revealed (Fig. 4). We may thus conclude that the studied QDs have no effect on cell morphology even in high concentrations. The assessment of the QD cytotoxicity on the breast carcinoma line: The cytotoxicity of the CdSe/L-Сys quantum dots was assessed on the ZR-75-1 line. There is characteristically no cytotoxic effect for the time intervals of 1, 3 and 18 h. After 24 h about 4 % of cells from the group injected with QDs (concentration of 17.5 µM/ml) accumulated PI, while for the two other groups these values were 3%. This result was not statistically different from the control group where the number of fluorescing cells was 2 for each 100 scanned. The number of dead cells in the ZR-75-1 culture did not exceed 3% in all control points in both the control and the experimental groups. The increase in cytotoxicity may be connected to the destruction of the l-Cys coating in a cell culture medium. Besides, the MNCs were taken from peripheral blood where lymphocytes do not proliferate without appropriate conditions created. As a result, the cytotoxic effect for this culture may have been more pronounced than for the immortalized ZR-75-1 line.
Acknowledgment
Introduction Stress state problems in the singular points of elastic bodies have been drawing the attention of researchers starting with the classical Williams study of 1952 [1]. These points may be angular, as well as positions where a change of boundary conditions or a discontinuity of elastic moduli in material occurs. The review in Ref. [2] offers an exhaustive bibliography on singular solutions of the problems of linear elastic fracture mechanics. As opposed to a homogeneous medium where stresses exhibit a singularity in the crack tip (, r is the distance from a crack tip), the order of stress singularities in an inhomogeneous medium may differ. For example, the stress singularity of a mode I or II interfacial crack with a perfect contact between the phases and the constant elastic moduli may exhibit an oscillating behavior. At the same time, the order of the singularity for an interfacial antiplane crack remains classical. However, if the contact between the materials is imperfect, the singularity will differ from the classical one, and it may be both strong (1/2 < λ < 1) and weak (0 < λ < 1/2) [3]. Moreover, for some models of imperfect contact, the asymptotic of the stresses will have two singular terms. Strong and weak singularities existing for a crack in a two- or a three-phase medium under the conditions of the antiplane problem also follows from the results of Refs. [4,5] The analysis of stress fields near the vertex of a composite wedge with piecewise-constant elastic properties and perfect phase contact was discussed in many studies, e.g., [4–9]. For some time, based on the conclusions in [10], the consensus regarding the functionally graded materials (FGM) whose elastic moduli vary continuously was that singularity exponent in the crack tip would always be the same as that in a homogeneous medium. However, in 2005, Carpinteri and Paggi showed [11] that for a crack growing in a gradient material with Young\'s modulus varying in the transverse direction the singularity exponent would differ from the classical value . The exponential elastic modulus function of the polar angle was used to ensure the separation of variables in the differential equation.