Computer simulation of field ion images of nanoporous structure in the irradiated materials

Computer simulation and interpretation of field ion microscopy images of ion irradiated platinum are discussed. Field ion microscopy technique provides direct precise atomic scale investigation of crystal lattice defects of atomically pure surface of material; at the same time it allows to analyze the structural defects in volume by controlled and sequential removal of surface atoms by electric field. Defects identification includes the following steps: at the first stage the type of crystalline structure and spatial orientation of crystallographic directions were determined. Thus, we obtain the data about exact position of all atoms of the given volume, i.e. the model image of an ideal crystal. At the second stage, the ion image was processed used the program to obtain the data about real arrangement of atoms of the investigated sample. At the third stage the program compares these two data sets, with a split-hair accuracy revealing a site of all defects in a material. Results of the quantitative analysis show that shape of nanopores are spherical or cylindrical, diameter on nanopores was varied from 1 to 5 run, their depth was fond to be from 1 to 9 nm. It was observed that nearly 40% of nanopores are concentrated in the subsurface layer 10 nm thick, the concentration of nanopores decreased linearly with the distance from the irradiated surface

A LABEL-FREE VOLTAMPEROMETRIC SENSOR BASED ON ELECTRIC CONDUCTIVE POLYMER COATINGS OF 3,4-ETHYLENEDIOXYTHIOPHENE / 3-ETHYNYLTHIOPHENE FOR DETERMINATION OF E.COLI AND S.AUREUS

This work was supported by a grant from the President of the Russian Federation for young scientists - candidates of sciences MK-567.2020.3

Direct estimation of SIR model parameters through second-order finite differences

SIR model is widely used for modeling the infectious diseases. This is a system of ordinary differential equations (ODEs). The numbers of susceptible, infectious, or immunized individuals are the compartments in these equations and change in time. Two parameters are the factor of differentiating these models. Here, we are not interested in solving the ODEs describing a certain SIR model. Given the observed data, we try to estimate the parameters that determine the model. For this, we propose a least squares approach using second-order centered differences for replacing the derivatives appeared in the ODEs. Then we arrive at a simple linear system that can be solved explicitly and furnish the approximations of the parameters. Numerical results over various artificial data verify the simplicity and accuracy of the new method. © 2020 John Wiley & Sons, Ltd

Dielectric functions and collective excitations in MgB_2

The frequency- and momentum-dependent dielectric function $\epsilon{(\bf q,\omega)}$ as well as the energy loss function Im[-$\epsilon^{-1}{(\bf q,\omega)}$\protect{]} are calculated for intermetallic superconductor $MgB_2$ by using two {\it ab initio} methods: the plane-wave pseudopotential method and the tight-binding version of the LMTO method. We find two plasmon modes dispersing at energies $\sim 2$-8 eV and $\sim 18$-22 eV. The high energy plasmon results from a free electron like plasmon mode while the low energy collective excitation has its origin in a peculiar character of the band structure. Both plasmon modes demonstrate clearly anisotropic behaviour of both the peak position and the peak width. In particular, the low energy collective excitation has practically zero width in the direction perpendicular to boron layers and broadens in other directions.Comment: 3 pages with 10 postscript figures. Submitted to PRB on May 14 200

Determination of E. Coli in Water Using the Enzyme Free Electrochemical Impedimetric Immunosensors

In this article, we have shown the results of E. coli bacteria determination in water using the enzyme free electrochemical immunosensor with covalent via click chemistry immobilized receptor layer in comparison with dropwise immobilized antibodies. Covalent immobilization was realized by creating precursors on the surface of the working electrode with the reaction of azide-alkyne copper-catalysed cycloaddition approach. The detection limit of the immunosensor with covalent and dropwise immobilization of antibodies was estimated as 6.6 CFU/ml and 11.2 CFU/ml, respectively, a linear range was 103-106 CFU/ml. Moreover, the sensor with "click"immobilized antibodies showed good stability for 30 days when stored in a phosphate buffer, while the sensor with dropwise immobilized receptor layer was stable for 3 days. © Published under licence by IOP Publishing Ltd.This work was supported by the Presidential Grants Fund of the Russian Federation (grant MK-567.2020.3)

Effects of 1,3,4-thiadiazine compound with antidepressant properties in ligation model of acute pancreatitis

Based on hypotheses concerning the role of stress in acute pancreatitis development, the experimental approach for the decrease stress damage via the use the compound with proven antistress/neuroleptic action was conducted. The study was aimed to discover 2-morpholino-5-phenyl-6H-1,3,4-thiadiazine hydrobromide (compound L-17) therapeutic action in experimental acute pancreatitis. The experimental model used was the ligation model. The trial was carried out on 50 male Wistar rats with average body weight 180-240g. Histological picture of the pancreas was studied and biochemical and enzyme-immunoassays were carried out on the first and seventh days. The significant reduction in mortality on the background of L-17 compound administration was observed. While levels of all cytokines increased in induced experimental acute pancreatitis groups, the cytokine level rise was decreased when compound L-17 was administered. On the cellular level, the study revealed L-17’s ability to prevent granulocytosis and decrease granulocytes infiltration to inflammatory foci. The decrease in inflammatory reaction magnitude and prevention of abscess formation in experimental acute pancreatitis accompanied by sistemic inflamamtion was due to L-17’s ability to reduce neutrophilia and neutrophil entry into the injury zone. © 2018, Slovak Academy of Sciences. All rights reserved.Government Council on Grants, Russian FederationMinistry of Education and Science of the Russian Federation, Minobrnauka: 17.7255.2017/8.9AAAA-A18-118020690020-1Funding information. Partly the study was supported by the Act 211 of the Government of Russian Federation, contract No 02.A03.21.0006; Government contract of Russian Federation with Institute of Immunology and Physiology (AAAA-A18-118020690020-1) and the Ministry of Education and Science of the Russian Federation (# 17.7255.2017/8.9)

ASSESSMENT OF EFFECTIVENESS OF ANTI-RECURRENT AND HORMONAL THERAPY IN WOMEN WITH UTERINE FIBROIDS IN PREGRAVIDAL PREPARATION

Aim. This study was designed to evaluate the effectiveness of sequential prescription of drugs for anti-recurrent therapy of the uterine fibroids (UF) and combined oral contraceptives (COC) in pregravidal preparation.Materials and methods. There was conducted a prospective, nonrandomized and controlled cohort study of 150 women with UF  who are planning a pregnancy after the organ-preserving treatment  of uterine fibroids by means of myomectomy with laparoscopic  access and pregravidal preparation. The immunohistochemical (IHC)  study of the intensity expression of Ki 67, p53, Bcl-2 was performed  for the differential diagnosis of reactive proliferation from dysplasia  in the distant fibroid node and the selection of anti-recurrent therapy.Results. The duration of the UF disease does not depend on the intensity of expression of p53, Ki-67 or Bcl-2, the level of expression  of the progesterone receptors in the distant fibroid node. A negative average correlation between the level of hemoglobin  before myomectomy, the duration of the disease (r = -0.3867) and  the number of nodes (r = -0.5389) was revealed. After the end of  the anti-recurrent treatment in women who underwent organ- preserving treatment of uterine fibroids, the prescription of COC is connected with a further decrease in the size of fibroid nodes remaining after myomectomy from 15.81±0.22 mm to 8.94±0.45  mm (p<0.05), the number of fibroid nodes from 2.25±0.08 to  0.91±0.06 (р<0.05).Conclusion. The combination of anti-recurrent therapy with the subsequent prescription of the COC for prevention of the UF growth  in women planning a pregnancy after myomectomy with endoscopic  access is highly effective

SMALL ORGANIC MOLECULES FOR SELECTIVE ELECTROCHEMICAL DETERMINATION OF NITROAROMATIC COMPOUNDS

The work was carried out with the financial support of the Russian Science Foundation grant No. 20-13-00142

Ubiquinol ameliorates endothelial dysfunction and increases expression of miRNA-34a in a rat model of pulmonary hypertension

In this research, we evaluate the effect of intravenously administrated solubilized ubiquinol on 4-week monocrotalin-induced pulmonary hypertension (PH) in rat

Electronic Structure and Valence Band Spectra of Bi4Ti3O12

The x-ray photoelectron valence band spectrum and x-ray emission valence-band spectra (Ti K _beta_5, Ti L_alpha, O K_alpha) of Bi4Ti3O12 are presented (analyzed in the common energy scale) and interpreted on the basis of a band-structure calculation for an idealized I4/mmm structure of this material.Comment: 6 pages + 7 PostScript figures, RevTex3.0, to be published in Phys.Rev.B52 (Oct.95). Figures also available via anonymous ftp at ftp://ftp.physik.uni-osnabrueck.de/pub/apostnik/BiTiO