State University Education Science Production Complex

Orël, Russia

State University Education Science Production Complex

Orël, Russia

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Dremin V.V.,State University Education Science Production Complex | Zherebtsov E.A.,State University Education Science Production Complex | Rafailov I.E.,Aston University | Vinokurov A.Y.,Aston University | And 4 more authors.
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2016

This study examines the effect of blood absorption on the endogenous fluorescence signal intensity of biological tissues. Experimental studies were conducted to identify these effects. To register the fluorescence intensity, the fluorescence spectroscopy method was employed. The intensity of the blood flow was measured by laser Doppler flowmetry. We proposed one possible implementation of the Monte Carlo method for the theoretical analysis of the effect of blood on the fluorescence signals. The simulation is constructed as a four-layer skin optical model based on the known optical parameters of the skin with different levels of blood supply. With the help of the simulation, we demonstrate how the level of blood supply can affect the appearance of the fluorescence spectra. In addition, to describe the properties of biological tissue, which may affect the fluorescence spectra, we turned to the method of diffuse reflectance spectroscopy (DRS). Using the spectral data provided by the DRS, the tissue attenuation effect can be extracted and used to correct the fluorescence spectra. © 2016 SPIE.


Rafailov I.E.,Aston University | Dremin V.V.,State University Education Science Production Complex | Litvinova K.S.,Aston University | Dunaev A.V.,State University Education Science Production Complex | And 2 more authors.
Journal of Biomedical Optics | Year: 2016

Urinary bladder diseases are a common problem throughout the world and often difficult to accurately diagnose. Furthermore, they pose a heavy financial burden on health services. Urinary bladder tissue from male pigs was spectrophotometrically measured and the resulting data used to calculate the absorption, transmission, and reflectance parameters, along with the derived coefficients of scattering and absorption. These were employed to create a "generic" computational bladder model based on optical properties, simulating the propagation of photons through the tissue at different wavelengths. Using the Monte-Carlo method and fluorescence spectra of UV and blue excited wavelength, diagnostically important biomarkers were modeled. Additionally, the multifunctional noninvasive diagnostics system "LAKK-M" was used to gather fluorescence data to further provide essential comparisons. The ultimate goal of the study was to successfully simulate the effects of varying excited radiation wavelengths on bladder tissue to determine the effectiveness of photonics diagnostic devices. With increased accuracy, this model could be used to reliably aid in differentiating healthy and pathological tissues within the bladder and potentially other hollow organs. © 2016 Society of Photo-Optical Instrumentation Engineers (SPIE).


Palmer S.,University of Dundee | Litvinova K.,Aston University | Dunaev A.,State University Education Science Production Complex | Fleming S.,University of Dundee | And 2 more authors.
Biomedical Optics Express | Year: 2016

Muscle invasive urinary bladder cancer is one of the most lethal cancers and its detection at the time of transurethral resection remains limited and diagnostic methods are urgently needed. We have developed a muscle invasive transitional cell carcinoma (TCC) model of the bladder using porcine bladder scaffold and the human bladder cancer cell line 5637. The progression of implanted cancer cells to muscle invasion can be monitored by measuring changes in the spectrum of endogenous fluorophores such as reduced nicotinamide dinucleotide (NADH) and flavins. We believe this could act as a useful tool for the study of fluorescence dynamics of developing muscle invasive bladder cancer in patients. © 2016 Optical Society of America.


PubMed | Aston University and State University Education Science Production Complex
Type: Journal Article | Journal: Journal of biomedical optics | Year: 2016

Urinary bladder diseases are a common problem throughout the world and often difficult to accurately diagnose. Furthermore, they pose a heavy financial burden on health services. Urinary bladder tissue from male pigs was spectrophotometrically measured and the resulting data used to calculate the absorption, transmission, and reflectance parameters, along with the derived coefficients of scattering and absorption. These were employed to create a generic computational bladder model based on optical properties, simulating the propagation of photons through the tissue at different wavelengths. Using the Monte-Carlo method and fluorescence spectra of UV and blue excited wavelength, diagnostically important biomarkers were modeled. Additionally, the multifunctional noninvasive diagnostics system LAKK-M was used to gather fluorescence data to further provide essential comparisons. The ultimate goal of the study was to successfully simulate the effects of varying excited radiation wavelengths on bladder tissue to determine the effectiveness of photonics diagnostic devices. With increased accuracy, this model could be used to reliably aid in differentiating healthy and pathological tissues within the bladder and potentially other hollow organs.


PubMed | Institute of Photonic Technology, Aston University, University of Dundee and State University Education Science Production Complex
Type: Journal Article | Journal: Medical engineering & physics | Year: 2015

Fluorescence spectroscopy has recently become more common in clinical medicine. However, there are still many unresolved issues related to the methodology and implementation of instruments with this technology. In this study, we aimed to assess individual variability of fluorescence parameters of endogenous markers (NADH, FAD, etc.) measured by fluorescent spectroscopy (FS) in situ and to analyse the factors that lead to a significant scatter of results. Most studied fluorophores have an acceptable scatter of values (mostly up to 30%) for diagnostic purposes. Here we provide evidence that the level of blood volume in tissue impacts FS data with a significant inverse correlation. The distribution function of the fluorescence intensity and the fluorescent contrast coefficient values are a function of the normal distribution for most of the studied fluorophores and the redox ratio. The effects of various physiological (different content of skin melanin) and technical (characteristics of optical filters) factors on the measurement results were additionally studied. The data on the variability of the measurement results in FS should be considered when interpreting the diagnostic parameters, as well as when developing new algorithms for data processing and FS devices.


Markov V.V.,Bryansk State University | Lebedeva L.I.,Bryansk State University | Kanatnikov N.V.,State University Education Science Production Complex
IOP Conference Series: Materials Science and Engineering | Year: 2015

The article describes technological aspects of the marking process using solid-state fibre laser. It presents the analysis of the technological modes and errors of the precise laser marking and establishes low density of the laser system as one of the causes of the poor quality of a laser seam. The article reviews the use of the following material laser marking is performed on - plastic with fine metal and conductive surface coating. © Published under licence by IOP Publishing Ltd.


Koziol Z.,State University Education Science Production Complex | Matukhin S.I.,State University Education Science Production Complex | Buduleva E.A.,Oryol State University
Optica Applicata | Year: 2014

Drift-diffusion computer simulation model available in Synopsys' Sentaurus TCAD User Guide is used to study electrical and optical characteristics of a separate-confinement heterostructure laser based on AlGaAs. We investigate the role of the width and depth of quantum-well active region, below and above the lasing threshold. The device properties depend on both, the number of bound quantum-well states and on closeness of the highest bound states to conduction or valence band offset. The lasing action may not exist at certain widths or depths of quantum-well, and the threshold current is a discontinuous function of these parameters, at such values of quantum-well width or depth when the highest quantum-well bound states cross conduction or valence band energy offset. The effects are more pronounced at low temperatures. Discontinuities in characteristics are found, at certain conditions, in temperature dependences as well. The carriers scattering time on quantum-well is shown to have a crucial role for the amplitude of discontinuities of these characteristics. The current below the lasing threshold and the threshold current density itself decrease with an increase of quantum-well scattering times and the amplitude of discontinuities decreases then as well. © Copyright 2007 T.Przerwa-Tetmajer.


Savin L.,State University Education Science Production Complex | Kornaev A.,State University Education Science Production Complex | Kornaeva E.,State University Education Science Production Complex
International Journal of Mathematics and Computers in Simulation | Year: 2016

The Magnus effect, which occurs with the oncoming flow around the rotating bodies, is known for a long time. The main purpose of the present paper was to identify the conditions of Magnus effect occurrence in a thin lubricant film of the fluid-film bearing and to obtain an approximate analytical dependency for its quantity evaluation. The mathematical model of the viscous incompressible fluid flow is based on the Navier-Stokes equation and the condition of incompressibility considering the non-stationarity of the process, inertia, viscous resistance and mass forces effect. As a result of evaluation of significance of the mathematical model equations terms by means of similarity theory and dimension analysis the conditions were determined as a dimensionless criteria, when inertia forces from the Magnus effect are significantly bigger than the mass and viscosity forces. Given the fulfillment of these conditions an analytical form was obtained to determine the hydrodynamic reaction of the lubricant. © 2016, North Atlantic University Union. All rights reserved.


Frolenkova L.Y.,State University Education Science Production Complex | Shorkin V.S.,State University Education Science Production Complex
PNRPU Mechanics Bulletin | Year: 2013

There are a number of problems for successful solutions to be aware of the surface energy, the energy and the force of adhesion and cohesion. An example is that of the bundle composites. The expression of the energy strength criterion is the total surface energy of the contacting elements or energy of adhesion. These values are determined by methods of the classical theory of elasticity is impossible. Power strength criteria using the limit values of powers - forces of adhesion and cohesion. They are usually determined experimentally, it is not always possible or economically unprofitable. The authors proposed a method for calculating the surface and adhesion energies of elastic bodies in a state of adhesion. It was considered by the authors as follows. Distributed over the boundary of the total surface energy is distributed over its volume free energy change occurring during the formation of the border. The adhesion of the two bodies along the contact surface is formed by a transition layer. In its physical and thermodynamic properties of one body continuously into the properties of another body. The method is based on a variant of the gradient model of continuous elastic medium. It is based on the assumption of many-potential nonlocal interaction infinitely small particles that make up the environment. More to the classic characteristics of the elastic state is calculated by differentiating the known expression bulk density of free energy. It is built on the basis of additional assumptions about the composition of the medium: the elastic part, the phonon and electron (for metals) gases.


Savin L.,State University Education Science Production Complex | Kornaev A.,State University Education Science Production Complex
Applied Mechanics and Materials | Year: 2014

The paper investigates the two-dimensional flow of an incompressible viscous fluid of complex rheology in the gap between two cylinders with respect to fluid friction bearings. The viscosity of the fluid is defined as a physical quantity field, satisfying the criterion of minimum friction loss approximated as a function of shear-strain rate and pressure. The resulting function is used to calculate the carrying capacity and the friction torque in the bearing. Computer experiment resulted in showing the effect of friction loss lowering due to considering complex rheology of lubricating material. © 2014 Trans Tech Publications, Switzerland.

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