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WAVELET-BASED AnALYSIS OF CEREBROVASCULAR DYnAMICS In nEWBORn RATS WITH InTRACRAnIAL HEMORRHAGES

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Journal of Innovative Optical Health Sciences 2014年第1期7卷 66-75页

作者： ALEXEY n.PAVLOV ALEXEY I.nAZIMOV olga n.pavlova VLADISLAV V.LYCHAGOV VALERY V.TUCHIn olga A.BIBIKOVA SERGEYS.SInDEEV OXAnA V.SEMYACHKInA-GLUSHKOVSKAYA Department of Physics Saratou State University 83 Astrakhanskaya str.Saratou 410012Russia

Intracranial hemorrhage(I)is a major problem of neonatal intensive *** incidence of Iistypically asymptomatic and'canmot be effectively detected by standard diagnostic *** mechanisms underlying IH are unknown but there is evidence that stress-induced disorders inadrenergic regulation of cerebral venous blood flow (CVBF) are among the main *** and qualitative:could significantly advance understanding ofthe nature of I in newbornslth1sions of CVBF in newborn rats withan experimental model of *** analysis is bas ed on theDoppler optical coheavelet-based approachthat provides sensitiv external *** resultsccompanied by asupprectivity to *** show that the values0nto the sympathicusindicate abnormal reactions associated with the developent of *** conclude that t he revealed areactivity of the cerebral veins to adrenaline represents a possible mechanism responsible forpat hological changes in CVBF.

关键词： Brain hemorhages optical coherence tomography cerebrovascular dynamics wavelet analy sis stress.

Characterization of cerebral blood flow dynamics with multiscale entropy

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Journal of Innovative Optical Health Sciences 2017年第5期10卷 85-93页

作者： Alexey n.Pavlov Arkady S.Abdurashitov olga n.pavlova Maria V.Ulanova Anastasia A.Bodrova natalia A.Shushunova Alexander P.Khorovodov Oxana V.Semyachkina-Glushkovskaya Yuri Gagarin State Technical University of Saratov 77 Politechnicheskaya Street Saratov 410054Russia Saratov national Research State University 83 Astrakhanskaya Street Saratov 410012Russia

Based on the laser speckle contrast imaging(LSCI)and the multiscale entropy(MSE),we study in this work the blood flow dynamics at the levels of cerebral veins and the surrounding network of microcerebral *** discuss how the phenylephrine-related acute peripheral bypertension is refected in the cerebral circulation and show that the observed changes are scale dependent,and they are signifcantly more pronounced in microcerebral vessels,while the macrocerebral dynamics does not demonstrate authentic inter-group *** also consider the permeability of blood-brain barrier(BBB)and study its opening caused by sound *** show that alterations associated with the BBB opening can be revealed by the analysis of blood flow at the level of macrocerebral vessels.

关键词： Cerebral blood flow laser speckle contrast imaging arterial pressure complexity

Optical in vivo and ex vivo imaging of glioma cells migration via the cerebral vessels:Prospective clinical application of the beta2-adrenoreceptors blockade for glioma treatment

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Journal of Innovative Optical Health Sciences 2018年第4期11卷 98-107页

作者： olga pavlova Alexander Shirokov Alexander Fomin nikita navolokin Andrey Terskov Alexander Khorovodov Anton namykin Alexey Pavlov Valery Tuchin Oxana Semyachkina-Glushkovskaya Interdisciplinary Center of Critical Technologies in Medicine Saratov State University 83 Astrakhanskaya Str.Saratov 410012Russia Institute of Biochemistry and Physiology of Plants and Microorganisms Russian Academy of Sciences13 Entuziastov Ave.Saratov 410049Russia Saratov State Medical University 112 Bolshaya Kazachia Str. Saratov 410012Russia Department of Optics and Biophotonics Saratov State University 83 Astrakhanskaya Str.Saratov 410012Russia Yuri Gagarin State Technical University of Saratov 77 Politechnicheskaya Str. Saratov 410054Russia Laboratory of Laser Diagnostics of Technical and Living Systems Institute of Precision Mechanics and Control of RAS 24 Rabochaya Str.Saratov 410028Russia Laboratory of Biophotonics Tomsk State University 36 Lenin's Ave.Tomsk 634050Russia

Malignant gliomas are highly invasive tumors that 1use the cerebral vessels for invasion due to high vascular fragility of the blood--brain barrier(BBB).On one hand,glioma is characterized by the BBB disruption,on the other hand,drug brain delivery via the BBB is a big challenge in glioma *** limited information about vascular changes associated with glioma growth is a reason of slow progress in prevention of glioma ***,we present in vrivo and er vrivo study of the BBB disruption and glioma cells(GCs)migration in rats using fuorescence and confocal *** uncovered a local breach in the BBB in the main tumor mass but not within the border of normal and malignant cells,where the BBB was impermeable for high weight *** migr ation of GCs were observed via the cerebral vessels with the intact BBB that was associated with macrophages *** mechanisms underlying glioma progression remain umknown but there is an evidence that the sympathetic nervous system(SnS)via activation of vascular beta2-adrenoreceptors(B2-ADRs)can play an important role in tumor *** results clearly show an increase in the expression of vascular B2-ADRs and production of the beta arrestin-1-co-factor of B2-ADRs signaling pathway in rats with *** blockade of B2-ADRs reduces the BBB disruption,macrophages infiltration,GCs migration and increases survival *** data suggest that the blockade of B2-ADRs may be a novel adjuvant therapeutic strategy to reduce glioma progression and prevent metastasis。

关键词： Glioma macrophages blood-brain barrier beta-2 adrenoreceptors bet a arrestin-1

Photodynamic diagnostics of early gastric cancer:Complexity measures of gastric microcirculation and new model of metastatic adenocarcinoma of rat stomach

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Journal of Innovative Optical Health Sciences 2019年第2期12卷 64-73页

作者： Alexey Pavlov Ekaterina Borisova olga pavlova Ilana Agranovich Alexander Khorovodov Andrey Terskov Aysel Mamedova Maria Klimova Latchezar Avramov Oxana Semyachkina-Glushkovskaya Saratov State University 83 Astrakhanskaya Str.Saratov 410012Russia Institute of Electronics Bulgarian Academy of Sciences Tsarigradsko Chaussee Blvd.72Sofia 1784Bulgaria

The detection of early gastric cancer that often develops asymptomatically is crucial for improving patient *** photodynamic diagnosis(PDD)of gastric cancer using 5-aminolevulinic acid/protoporphyrin IX(5-ALA/PpIX)has been reported in several ***,the selectivity of PDD of gastric tumor is poor with often false-positive results that require the development of new methods to improve PDD for early gastric ***,a measure of the complexity of gastric microcirculation(multi-scale entropy,MSE)and the detrendedfluctuation analysis(DFA)were applied as additional tools to detect early gastric cancer in *** this experimental study,we used our original model of metastatic adenocarcinoma in the stomach of a *** induce a gastric tumor,we used a long-term combination(for 9 months,which is 1/2 of the life of rats)of two natural factors,such as chronic stress(overpopulation being typical for modern cities)and the daily presence of nitrites in food and drinks,which are common ingredients added to processed meat andfish to help preserve *** results clearly show that both methods,namely,PDD using 5-ALA/PpIX and complexity/correlation analysis,can detect early gastric cancer,which was confirmed by histological ***-cancerous areas in the stomach were detected as an intermediatefluorescent signal or MSE level between normal and malignant lesions of the ***,in some cases,PDD with 5-ALA/PpIX produced a false-positivefluorescence of exogenousfluorophores due to its accumulation in benign and inflammatory areas of the *** fact indicates that the PDD itself is not sufficient for the correct diagnosis of gastric cancer,and the use of additional characteristics,e.g.,complexity measures or scaling exponents,can significantly improve the diagnostic accuracy of PDD of gastric cancer that should be confirmed in further clinical studies and applications.

关键词： Experimental model of gastric cancer in animals highly heterogeneous adenocarcinoma photodynamic diagnosis complexity measures gastric microcirculation

Searching for the brightest stars in galaxies outside the Local Group

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Research in Astronomy and Astrophysics 2021年第4期21卷 264-270页

作者： nikolay Tikhonov olga Galazutdinova olga Sholukhova Antoniya Valcheva Petko nedialkov olga Merkulova Special Astrophysical Observatory Nizhnij ArkhyzKarachai-Cherkessian RepublicRussia 369167 Department of Astronomy Sofia University1504 Sofia15 Tsar Osvoboditel Blvd.SofiaBulgaria Astronomical Institute St.Petersburg State UniversityUniversitetskii pr.28St.Petersburg198504 Russia

This paper introduces a technique for searching for bright massive stars in galaxies beyond the Local *** search for massive stars,we processed the results of stellar photometry from the Hubble Space Telescope(HST)images using the DAOPHOT and DOLPHOT *** results of such searches are demonstrated with examples of the galaxies DDO 68,M94 and nGC *** the galaxy DDO 68,the LBV star changes its brightness,and massive stars in M94 can be identified by excess in the Ha *** the galaxy nGC 1672,we measure the distance for the first time by the TRGB method,which enabled determining the luminosities of the brightest stars,likely hypergiants,in the young star formation *** far,we have performed stellar photometry on HST images of 320 northern sky galaxies located at a distance less than 12 *** allowed us to identify 53 galaxies with probable *** photometric and spectral observations of these galaxies are planned to search for massive stars.

关键词： stars:massive stars:variables:LBV galaxies:individual:M94 DDO 68 nGC 1672

A word about the teacher

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Research in Astronomy and Astrophysics 2019年第3期19卷 35-46页

作者： Galina n.Dryomova olga V.Eretnova Tatyana S.Polushina Russian Federal nuclear Centre named after academician E.I.Zababakhin Chelyabinsk State University Ural Federal University named after the First President of Russia B.n.Yeltsin

This is a memorial report on the biography and scientific heritage of M.A. Svechnikov — an outstanding scientist and teacher, the founder of the Ural school of close binary stars and the author of the classification ... 详细信息

关键词： catalogs photometric-spectroscopic-stars eclipsing variables classification scheme-close binary stars

The Fifth Edition of the General Catalogue of Variable Stars:experiences in the constellation Centaurus

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Research in Astronomy and Astrophysics 2018年第7期18卷 93-100页

作者： nikolay n.Samus Elena n.Pastukhova olga V.Durlevich Elena V.Kazarovets Institute of Astronomy Russian Academy of Sciences Sternberg Astronomical Institute Lomonosov Moscow University

We have recently announced that the General Catalogue of Variable Stars enters the stage of its fifth, purely electronic edition （GCVS 5.1）. We have included 1408 variable stars in the constellation Centaurus in this new version, GCVS 5.1. Working on this revision, we applied current possibilities from data mining, suggested new variability types for many variable stars and found new light elements for a large number of periodic variables. This paper describes the work completed during the preparation of GCVS 5.1 for Centaurus and discusses in detail a number of the most astrophysically significant cases.

关键词： catalogs - techniques photometric - stars variables general - binaries eclipsing

InITIAL VALUE TECHnIQUES FOR THE HELMHOLTZ AnD MAXWELL EQUATIOnS

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Journal of Computational Mathematics 2007年第3期25卷 368-373页

作者： Frank natterer olga Klyubina Department of Mathematics University of MünsterGermany

We study the initial value problem of the Helmholtz equation with spatially variable wave number. We show that it can be stabilized by suppressing the evanescent waves. The stabilized Helmholtz equation can be solved numerically by a marching scheme combined with FFT. The resulting algorithm has complexity n^2 log n on a n x n grid. We demonstrate the efficacy of the method by numerical examples with caustics. For the Maxwell equation the same treatment is possible after reducing it to a second order system. We show how the method can be used for inverse problems arising in acoustic tomography and microwave imaging.

关键词： Stability of elliptic initial value problems Parabolic wave equation Inverseproblems in acoustics and electromagnetics.

Euxinia as a dominant process during OAEla(Early Aptian)on the Eastern Russian Platform and during OAElb(Early Albian)in the Middle Caspian

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Science China Earth Sciences 2017年第1期60卷 58-70页

作者： Svetlana O. ZORInA Oksana V. pavlova Bulat M. GALIULL1n Vladimir P. MOROZOV Alexey A. ESKIn Institute of Geology and Petroleum Technologies Kazan Federal University 4/5 Kremlyovskaya street Kazan 420008 Russian Federation

A detailed study of the mineral composition and microstructure of the black shales associated with OAE1 a （Eastern Russian Platform）, OAElb （Middle Caspian）, and the host rocks has been carried out using X-ray diffraction, scanning electron microscopic, and microprobe analyses. The results provide important constraints for depositional environments in the sedimentary basins. Black shales with pyrite framboids imply euxinic （sulfidic） conditions with increased organic matter preservation. Disintegrating framboids suggest partial or complete dissolution of the organic matter inside the framboids due to increasing water oxygenation. OAEla on the Eastern Russian Platform is heterogeneous as it includes thin interbeds of concretionary coccolith limestones within the interval of bituminous shales, and correlates with the Lower Aptian Rhagodiscus angustus nannofossil zone. The coccolith limestones indicate short intermittent episodes of interrupted stagnation, rapid oxygenation, and restoration of normal marine conditions. The presence of montmorillonite, albite, microcline, and diopside in the bituminous siltstones and in the host siltstones of OAEla on the Eastern Russian Platform, as well as a high content of titanium in the black siltstones correlated with OAEIb in the Middle Caspian allow proposing significant input of pyroclastic material into the extant sea.

关键词： OAEIa OAElb Black shales Pyrite framboids Euxinia Oxygenation Eastem Russian Platform MiddleCaspian Cretaceous