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Quantification of glucose and glycerol diffusion in myocardium

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Journal of Innovative Optical Health Sciences 2015年第3期8卷 46-55页

作者： Daria K.Tuchina Alexey N.Bashkatov Elina A.Genina valery V.Tuchin Research-Educational Institute of Optics and Biophotonics Saratov State University Saratov 410012Russia Laboratory of Laser Diagnostics of Technical and Living Systems Institute of Precise Mechanics and Control RAS Saratov 410028 Russia Optoelectronics and Measurement Techniques Laboratory P.O.Box 4500 University of Oulu FIN-90014OuluFinland

The results on determination of glucose and glycerol difusion cofficients in myocardium tissuse are *** method is based on the measurement and analysis of temporal dependence of tissue optical collimated transmittance umder action of a hyperosmotic *** temporal tissue response is related to the rate of the agent and water diffusion in a *** diffusion coefficients for tssue fAuid fluxes at glucose and glycerol application to the myocardium at 20℃ have been estimated as(4.75±3.40)×10^(-7) and(7.71±4.63)×10^(-7) cm^(2)/s,respectively.

关键词： Difusion cofficient optical clearing delhydration scattering.

Viscosity of Nanofluids. Why It Is Not Described by the Classical Theories

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Advances in Nanoparticles 2013年第3期2卷 266-279页

作者： valery Ya. Rudyak Department of Theoretical Mechanics Novosibirsk State University of Architecture and Civil Engineering Novosibirsk Russian Federation

Transport properties of nanofluids are extensively studied last decade. This has been motivated by the use of nanosized systems in various applications. The viscosity of nanofluids is of great significance as the application of nanofluids is always associated with their flow. However, despite the fairly large amount of available experimental information, there is a lack of systematic data on this issue and experimental results are often contradictory. The purpose of this review is to identify the typical parameters determining the viscosity of nanofluids. The dependence of the nanofluid viscosity on the particles concentration, their size and temperature is analyzed. It is explained why the viscosity of nanofluid does not described by the classical theories. It was shown that size of nanoparticles is the key characteristics of nanofluids. In addition the nanofluid is more structural liquid than the base one.

关键词： Nanofluids Gas Nanosuspensions Nanoparticles Viscosity Kinetic Theory Molecular Dynamics Rheology of Nanofluids Effect of Nanoparticles Size

Changes in Ice Cover Duration and Maximum Ice Thickness for Rivers and Lakes in the Asian Part of Russia

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Natural Resources 2018年第3期9卷 73-87页

作者： valery Vuglinsky Dmitry Valatin St. Petersburg State University St. Petersburg Russia

This article is concerned with assessment of changes in two critical characteristics of lake and river ice regime, namely ice cover duration and maximum ice thickness, in the period from the beginning of the 80s to the present, which is characterized by higher temperatures in the Northern Hemisphere compared with the previous period. The above ice regime characteristics are often limiting factors in winter operation of lakes and rivers (navigation, hydraulic construction works in cold period, construction of ice roads etc.). Assessment of changes in ice characteristics of lakes and rivers has been made for 52 river and five lake gauging sites of the Asian part of Russia (APR) using long-term observation data from the Russian observing network. Long-term series of the above characteristics were divided into two periods: from 1955 to 1979 (the period of stationary climate) and from 1980 to 2014 (non-stationary climate) and assessed from the point of view of their homogeneity and trend significance by Student’s t-test. The research has found that at most of the sites in the APR, both ice cover duration and maximum ice thickness decreased during non-stationary climate period compared with the previous one. The greatest quantitative changes have occurred in the Eastern Siberia (average net decrease in ice cover duration amounted to 7 ***-1 and in maximum ice thickness-20 ***-1) and in the Amur River basin (7 ***-1 and 17 ***-1 respectively).

关键词： Ice Regime Rivers Lakes Asian Part of Russia Changes Last Three Decades

Combined Algorithms of Optimal Resource Allocation

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Applied Mathematics 2012年第1期3卷 78-85页

作者： valery I. Struchenkov 不详

Under study is the problem of optimum allocation of a resource. The following is proposed: the algorithm of dynamic programming in which on each step we only use the set of Pareto-optimal points, from which unpromising points are in addition excluded. For this purpose, initial approximations and bilateral prognostic evaluations of optimum are used. These evaluations are obtained by the method of branch and bound. A new algorithm “descent-ascent” is proposed to find upper and lower limits of the optimum. It repeatedly allows to increase the efficiency of the algorithm in the comparison with the well known methods. The results of calculations are included.

关键词： Dynamic Programming The Pareto Set Branch and Bound Method The Curse of Dimensionality Algorithm “Descent-Ascent”

Modeling Mechanical Patterns for Striated Muscles

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Journal of Biomedical Science and Engineering 2014年第8期7卷 473-496页

作者： valery B. Kokshenev Departamento de Fisica Instituto de Ciencias Exatas Universidade Federal de Minas Gerais Belo Horizonte Brazil

Muscles show a surprisingly large variety of functions when they mechanically respond to different environmental requests. However, the in vivo workloop studies distinguish well only four patterns of skeletal muscles, producing positive, negative, almost zero and zero net works, that qualifies them respectively as motors, brakes, struts, and springs. While much effort of comparative biologists has been done in searching for muscle design patterns, no fundamental concepts underlying such four primary patterns were established. In this interdisciplinary study, continuum mechanics is applied to the problem of muscle structure in relation to function. The known ability of a powering muscle as whole to be tuned via natural (resonant) frequency to the efficient locomotion is now modeled through the non-linear elastic muscle moduli, controlling both the contraction frequency and velocity. When incorporated in activated skeletal and cardiac (striated) muscles via the mechanical similarity between loaded and reaction forces, further exploration of elastic force patterns (borrowed from solid state physics) yields an explicit rationalization for currently known locomotor muscle patterns. Besides explanation of the origin of allometric exponents derived for leg muscles in animals adapted to fast running and wing muscles in flying birds, the skeletal and cardiac muscles are patterned through the primary and secondary high power activities. Further applications are expected to be useful in designing of artificial muscles and modeling living and extinct animals.

关键词： Continuum Mechanics Modeled Muscles Workloops Scaling Elastic Effects Allometry Active Stiffness

Blood-brain barrier and cerebral blood flow: Age differences in hemorrhagic stroke

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Journal of Innovative Optical Health Sciences 2015年第6期8卷 101-110页

作者： Semyachkina-Glushkovskaya Oxana Sindeeva Olga Abdurashitov Arkady Sindeev Sergey Zinchenko Ekaterina Gekaluk Artem Ulanova Maria Mohanad Kassim Yankovskaya Ludmila Tuchin valery Department of Physiology of Human and Animals Saratov State University Astrakhanskaya Str.83 Saratov 410012Russia Department of Optics and Biophotonics Saratov State University Astrakhanskaya Str.83 Saratov 410012Russia Department of Therapy Grodno Medical State University Limozha Str.23Grodno 230005Byelorussia Laboratory of Biophotonics Tomsk State University Tomsk 634050Russia

Neonatal stroke is similar to the stroke that occurs in adults and produces a significant morbidity and long-term neurologic and cognitive *** are important differences in the factors,clinical events and outcomes associated with the stroke in infants and ***,mechanisms underlying age differences in the stroke development remain largely ***,treatment guidelines for neonatal stroke must extrapolate from the adult data that is often not suitable for *** new information about differences between neonatal and adult stroke is essential for identification of significant areas for future treatment and effective prevention of neonatal ***,we studied the development of stress-induced hemorrhagic stroke and possible mechanisms underlying these processes in newborn and adult *** histological methods and magnetic resonance imaging,we found age differences in the type of intracranial *** rats demonstrated small superficial bleedings in the cortex while adult rats had more severe deep bleedings in the *** Doppler optical coherent tomography,we found higher stress-reactivity of the sagittal sinus to deleterious effects of stress in newborn *** rats suggesting that the cerebral veins are more vulnerable to negative stress factors in neonatal *** brain in ***,adult but not newborn rats demonstrated the stroke-induced breakdown of blood brain barrier(BBB)*** one of possible mechanisms underlying the higher resistance to stress-related stroke injures of cerebral vessels in newborn rats compared with adult animals is the greater expression of two main tight junction proteins of BBB(occludin and claudin-5)in neonatal *** brain in rats.

关键词： Stroke age di®erences cerebral blood flow brain blood barrier

Topological to trivial insulating phase transition in stanene

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Nano Research 2016年第3期9卷 774-778页

作者： Michel Houssa Bas van den Broek Konstantina Iordanidou Anh Khoa Augustin Lu Geoffrey Pourtois Jean-Pierre Locquet valery Afanas'ev Andre Stesmans Department of Physics and Astronomy University of Leuven Celestijnenlaan 200D B-3001 Leuven Belgium imec 75 Kapeldreef B-3001 Leuven Belgium

Electronic properties of stanene, the Sn counterpart of graphene are theoretically studied using first-principles simulations. The topological to trivial insulating phase transition induced by an out-of-plane electric field or by quantum confinement effects is predicted. The results highlight the potential to use stanene nanoribbons in gate-voltage controlled dissipationless spin-based devices and are used to set the minimal nanoribbon width for such devices, which is typically approximately 5 nm.

关键词： two-dimensional (2D)materials topological insulators density functional theory(DFT) simulations electronic structure

Medical images classification for skin cancer using quantitative image features with optical coherence tomography

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Journal of Innovative Optical Health Sciences 2016年第2期9卷 8-16页

作者： Wei Gao valery P.Zakharov Oleg O.Myakinin Ivan A.Bratchenko Dmitry N.Artemyev Dmitry V.Kornilin Department of Laser and Biotechnical Systems Samara State Aerospace University

Optical coherence tomography(OCT)is employed in the diagnosis of skin ***,quantitative image features extracted from OCT images might be used as indicators to classify the skin *** the present paper,we investigated intensity-based,texture-based and fractalbased features for automatically classifying the melanomas,basal cell carcinomas and pigment *** estimating equations were used to test for differences between the skin tumors.A modified p value of<0.001 was considered statistically *** increase of mean and median of intensity and significant decrease of mean and median of absolute gradient were observed in basal cell carcinomas and pigment nevi as compared with *** decrease of contrast,entropy and fractal dimension was also observed in basal cell carcinomas and pigment nevi as compared with *** results suggest that the selected quantitative image features of OCT images could provide useful information to differentiate basal cell carcinomas and pigment nevi from the *** research is warranted to determine how this approach may be used to improve the classification of skin tumors.

关键词： Optical coherence tomography skin tumor texture analysis fractal analysis differentiate box counting

Reducing the Dose of Local Anesthetic Reduces the Duration of Analgesia—Myth or Reality: A Double-Blind Randomized Study

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Open Journal of Anesthesiology 2015年第1期5卷 7-12页

作者： Piacherski valery Marachkou Aliaksei Department of Anesthesiology and Intensive Care Health Care Institution “Mogilev Regional Hospital” Mogilev Republic of Belarus

Background: The aim of the study is to determine the effect of a reduction in dose of local anesthetic blockade on the development of the sciatic nerve. Methods: Forty blocks of sciatic nerve were used in a double-blind randomized research, under ultrasonic guidance, using an electric stimulator with the peripheral nerves. Forty patients were divided into 2 equal groups. In the first group, a sciatic nerve block was performed with 5 ml of 0.75% ropivacaine solution (37.5 mg);in the second group, 10 ml of 0.75% ropivacaine solution (75 mg) was used. The assessment of the time required for developing sensory and motor blocks was carried out from the beginning of local anesthetic solution injection in the fascial sheath of the sciatic nerve. Results: Demographic data of patients were identical in the two sample groups. The time required for achieving a complete sensory block in groups treated with 5 and 10 ml ropivacaine was 45 (40;48) and 30 (28;30) min, respectively, (р 0.05. Conclusions: Complete blockade of the sciatic nerve is developed using 5 ml of 0.75% ropivacaine. Reducing the dose of ropivacaine prolongs the latent period of the LA during the blockade of the sciatic nerve. Time of postoperative analgesia was not significantly changed.

关键词： Ropivacaine Sciatic Nerve Ultrasound Guidance