Derivation of the Gutenberg-Richter Empirical Formula from the Solution of the Generalized Logistic Equation

We have written a new equation to study the statistics of earthquake distributions. We call this equation "the generalized logistic equation". The Gutenberg-Richter frequency-magnitude formula was derived from the solution of the generalized logistic equation as an asymptotic case in approximation of large magnitudes. To illustrate how the found solution of the generalized logistic equation works, it was used to approximate the observed cumulative distribution of earthquakes in four different geological provinces: the Central Atlantic (40N-25N, 5W-35W), Canary Islands, Magellan Mountains (20N-9S, 148E-170E), and the Sea of Japan. This approximation showed the excellent fit between the theoretical curves and observed data for earthquake magnitudes 1<m<9.Comment: 10 pages, 2 figures, 1 table, 8 references. Submitted to Natural Science, Earthquakes special issu

On the phonon-induced superconductivity of disordered alloys

A model of alloy is considered which includes both quenched disorder in the electron subsystem (``alloy'' subsystem) and electron-phonon interaction. For given approximate solution for the alloy part of the problem, which is assumed to be conserving in Baym's sense, we construct the generating functional and derive the Eliashberg-type equations which are valid to the lowest order in the adiabatic parameter.The renormalization of bare electron-phonon interaction vertices by disorder is taken into account consistently with the approximation for the alloy self-energy. For the case of exact configurational averaging the same set of equations is established within the usual T-matrix approach. We demonstrate that for any conserving approximation for the alloy part of the self-energy the Anderson's theorem holds in the case of isotropic singlet pairing provided disorder renormalizations of the electron-phonon interaction vertices are neglected. Taking account of the disorder renormalization of the electron-phonon interaction we analyze general equations qualitatively and present the expressions for $T_{c}$ for the case of weak and intermediate electron-phonon coupling. Disorder renormalizations of the logarithmic corrections to the effective coupling, which arise when the effective interaction kernel for the Cooper channel has the second energy scale, as well as the renormalization of the dilute paramagnetic impurity suppression are discussed.Comment: 59 pages, 10 Eps figures, LaTe

On the relevance of quantum corrections to the matter stress-energy tensor in eternally expanding universes

We study a toy-model of continuous infinite expansion of space-time with the flat start. We use as the gravitational background a conformaly flat metric with an exponentially growing factor in conformal time. We aim to clarify some properties of quantum fields in such a gravitational background. In particular, we calculate one-loop corrections to the Keldysh propagator to verify the fact of secular growth of the occupation number and anomalous quantum average in the massless scalar field theory with selfinteractions. We perform the calculation in arbitrary dimensions with the use of the Schwinger-Keldysh technique. We get a secular growth which is not of a kinetic type. We provide some results for the case of generic interaction $\frac{\lambda}{b!}\phi^b$.Comment: 21 pages, 2 figure

First-principles Calculations of the Electronic Structure and Spectra of Strongly Correlated Systems: Dynamical Mean-field Theory

A recently developed dynamical mean-field theory in the iterated perturbation theory approximation was used as a basis for construction of the "first principles" calculation scheme for investigating electronic structure of strongly correlated electron systems. This scheme is based on Local Density Approximation (LDA) in the framework of the Linearized Muffin-Tin-Orbitals (LMTO) method. The classical example of the doped Mott-insulator La_{1-x}Sr_xTiO_3 was studied by the new method and the results showed qualitative improvement in agreement with experimental photoemission spectra.Comment: 11 pages, 3 Postscript figures, LaTeX, submit in Journal of Physics: Condensed Matte

Electric-field-induced monoclinic phase in (Ba,Sr)TiO3_3 thin film

We have studied electric-field-induced symmetry lowering in the tetragonal (001)-oriented heteroepitaxial (Ba$_{0.8}$Sr$_{0.2}$)TiO$_3$ thin film deposited on (001)MgO substrate. Polarized micro-Raman spectra were recorded from the film area in between two planar electrodes deposited on the film surface. Presence of \textit{c}-domains with polarization normal to the substrate was confirmed from polarized Raman study under zero field, while splitting and hardening of the \textit{E}(TO) soft mode and polarization changes in the Raman spectra suggest monoclinic symmetry under external electric field

The role of immunotherapy in the management of metastatic/recurrent female reproductive system neoplasms

In 2019 malignant neoplasms of the female reproductive system (ovarian cancer, (OC), endometrial carcinoma (EC) and cervical cancer (CC) were diagnosed in 58 860 patients – 17.6% of all malignant tumors in women in Russia. The morbidity and mortality rates from these neoplasms remain high over the past 10 years. This article provides a detailed review of the current evidence base for  the  use of  various immunotherapeutic agents in  mentioned malignant neoplasms. It has been demonstrated that in  relapsed OC (ROC), the  only proved indication for  immunotherapy is tumors with microsatellite instability (MSI), whereas PD-L1 does not have an independent role in this disease. MSI occurs in approximately 8% of patients with metastatic OC. A significantly higher frequency MSI — up to 25% is detected in metastatic EC. MSI-positive subtype of the disease is characterized by an extremely high sensitivity to immunotherapy - the  rate of  objective response with pembrolizumab exceeds 50%. For  MS-stable  EC, the  combination of  pembrolizumab and lenvatinib is an effective therapeutic option. In  advanced CC, on the other hand, PD-L1 has a predictive role for immunotherapy efficacy — the KEYNOTE-158 study showed that about 15% of  patients with extensively pretreated metastatic PD-L1-positive CC can achieve long-term remission with pembrolizumab compared to 0% in PD-L1 negative tumors. Current evidence shows that PD-L1 expression can be observed in ≥ 30% of patients