[en] We consider the problem of measuring red blood cell deformability by laser diffractometry in shear flow (ektacytometry). A new equation is derived that relates the parameters of the diffraction pattern to the width of the erythrocyte deformability distribution. The numerical simulation method shows that this equation provides a higher accuracy of measurements in comparison with the analogous equation obtained by us earlier. (laser biophotonics)

[en] Stimulated Raman scattering (SRS) of intense laser radiation in hot inhomogeneous plasma is considered. Expression for SRS increment, taking account of electron plasma wave damping, plasma inhomogeneity and pumping radiation modulation is derived. 21 refs

[en] A theoretical model is developed for calculating the impulse response of an ensemble of inhomogeneous quantum oscillators perturbed by collisions. Transformation of the impulse response was studied in detail over a wide range of buffer gas pressures. The results can be used for data analysis in transient CARS (coherent anti-stokes Raman scattering) spectroscopy of metal atoms. The results also showed why the frequency exchange effect observed in thallium atoms is absent in thallium. 22 refs., 2 figs

[en] The problem of suppressing stimulated Raman scattering in plasma under laser thermonuclear fusion is considered. Cases of uniform plasma with noise pumping, nonuniform plasma with monochromatic and noise pumping as well as the case nonuniform plasma and pumping with linear frequency modulation are discussed

[en] Short note

[en] The problem of measuring red blood cell deformability by laser diffractometry in shear flow (ektacytometry) is considered. An algorithm has been developed for measuring the four central parameters of the erythrocyte deformability distribution, i.e. mean value, variance, asymmetry coefficient and kurtosis. The algorithm is designed to work with the peripheral part of the diffraction pattern and serves to analyse weakly inhomogeneous ensembles of red blood cells. (paper)

[en] The iso-intensity line curvature algorithm in laser ektacytometry of red blood cells is investigated by numerical simulation. The algorithm is designed to measure the average deformability, as well as the width and asymmetry of the red blood cell deformability distribution in a blood sample under study. The accuracy and scope of the algorithm are determined. Using a bimodal ensemble as an example, the possibility of determining the fraction of weakly deformable red blood cells in a blood sample by laser ektacytometry is demonstrated. (laser medicine)

[en] The paper is devoted to development of the laser ektacytometry technique for evaluation of the statistical characteristics of inhomogeneous ensembles of red blood cells (RBCs). We have analyzed theoretically laser beam scattering by the inhomogeneous ensembles of elliptical discs, modeling red blood cells in the ektacytometer. The analysis shows that the laser ektacytometry technique allows for quantitative evaluation of such population characteristics of RBCs as the cells mean shape, the cells deformability variance and asymmetry of the cells distribution in the deformability. Moreover, we show that the deformability distribution itself can be retrieved by solving a specific Fredholm integral equation of the first kind. At this stage we do not take into account the scatter in the RBC sizes. - Highlights: • Theoretical analysis of diffraction patterns in laser ektacytometer is performed. • Relations between intensity distribution and shape parameters of RBC are found. • RBC deformability distribution can be calculated from the diffraction pattern. • Experimental results are in good agreement with the theoretical conclusions

[en] Using a simple theoretical model we have obtained approximate relations between the characteristics of particles modeling red blood cells and the parameters of the diffraction pattern produced by a laser beam diffracted in the ektacytometer. Laser beam diffraction by an ensemble of transparent elliptical discs with different shapes is considered. We have shown a feasibility of measuring certain parameters of the particles distribution in shapes by using the laser ektacytometry technique. -- Highlights: ► We consider laser beam diffraction by an ensemble of transparent elliptical discs. ► We justify modeling the shear-deformed erythrocytes by transparent elliptical discs. ► We analyze intensity distributions in the diffraction patterns of a laser ektacytometer. ► We show that the patterns are sensitive to shape distributions of the particles. ► Theoretical and experimental results agree well in case of bimodal distribution