A new method for solving the inverse problem of seismology is described in this paper. The problem is formulated as follows: the travel times of body waves are given at a discrete set of points, and we are required to find in the (V, Y ) plane (V being the velocity and Y the depth) the closed area which contains all velocity-depth curves corresponding to the given data. The method is based on the use of the function z(p) = T ( p ) -p X ( p ) , p being the ray parameter, T the travel time, and X the epicentral distance.This method has the following advantages: it does not necessarily involve the estimation of p by numerical differentiation of the travel times; and it does not involve any interpolation of the travel-time curve between actual observations. Only two assumptions are made: spherical symmetry of the structure (the absence of horizontal inhomogeneities), and the postulation of a lower limit for the velocity in low velocity zones. The function z ( p ) is estimated directly from the observed (Ti, Xi) as a singular solution of the Clairaut equation with free term T ( X ) .Application of the method is illustrated using data from deep seismic sounding in Turkmenistan.

Further development of the theory and practice of the method for solving the inverse problem of seismology suggested in Bessonova et al. is described in this paper. The problem is formulated as follows: the travel times of body waves are given at a discrete set of points, and we are required to find in the (V, Y) plane (V is the velocity and Y is the depth) the closed area which contains all velocity-depth curves corresponding to the given data. A spherically symmetric model is assumed and a lower limit for the velocity in the low velocity zones is postulated. The method is based on the use of the function z(p) = T ( p ) -p X ( p ) , p being the ray parameter, T the travel time, and X the epicentral distance. A new formula which expresses the velocity-depth curve in terms of the function r(p) is used to construct the required area. A statistical method of interpretation allows us to construct the confidence region which contains the velocity-depth curve at a given confidence level. Application of the method is illustrated using earthquake data to investigate the velocity distribution in the mantle.

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Introduction. One of the urgent tasks in modern transplantology is the search of biomarkers for predicting and early diagnosis of graft dysfunction.Objective. The study objective was to determine the biomarkers of liver graft dysfunction.Material and methods. We have examined 19 recipients who underwent liver transplantation and 36 healthy blood donors. Levels of 7 serum cytokines were measured by multiparametric fluorescence analysis with magnetic microspheres (xMAP technology, Luminex 200, USA). Statistical analysis was carried out by methods of nonparametric statistics. To determine the predictive value of the test, a ROC-analysis was performed.Results and discussion. We found that the interleukin-8 level was 3.6 times higher in recipients with liver graft dysfunction compared to those who had an uneventful postoperative course. The diagnostic sensitivity of the test was 75%, the specificity was 91%, and negative predictive value was 84.6.Conclusion. Serum interleukin-8 measurement provides a biomarker for early predicting a post-transplant liver graft dysfunction development