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A rened analytical model for reconstruction problems in diuse reectance spectroscopy

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 33-51页

作者： Ekaterina Sergeeva Daria Kurakina ilya Turchin and Mikhail Kirillin A.V.gaponov-grekhov institute of applied physics of the russian academy of sciences ulyanov st.46 603950nizhny novgorodrussia

A rened analytical model of spatially resolved diffuse reectance with small source-detector separations(SDSs)for the in vivo skin studies is *** to the conventional model developed by Farrell et al.,it accounts for the limited acceptance angle of the *** rened model is validated in the wide range of optical parameters by Monte Carlo simulations of skin diffuse reectance at SDSs of units of *** of uniform dermis and two-layered epidermis-dermis structures are *** accuracy of the rened model compared to the conventional one is demonstrated in the separate,constraint-free reconstruction of absorption and reduced scattering spectra of uniform dermis from the Monte Carlo simulated *** the case of epidermis-dermis geometry,the recovered values of reduced scattering in dermis are overestimated and the recovered values of absorption are underestimated for both analytical ***,in the presence of a thin mismatched topical layer,only the effective attenuation coe±cient of the bottom layer can be accurately recovered using a diffusion theorybased analytical model while separate reconstruction of absorption and reduced scattering fails due to the inapplicability of the method of ***-ndings require implementation of more sophisticated models of light transfer in inhomogeneous media in the recovery algorithms.

关键词： Diffuse reffectance spectroscopy in vivo skin studies optical properties reconstruction diffuse approximation Monte Carlo simulations method of images

High Accuracy Finite Volume Method for Solving Nonlinear Aeroacoustics Problems on Unstructured Meshes

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Chinese Journal of Aeronautics 2006年第2期19卷 97-104页

作者： ilya ABALAKIN Alain DERVIEUX Tatiana KOZUBSKAYA Institute for Mathematical Modelling RAS . MoscowRussia INRIA Sophia-Antipolis France Institute for Mathematical Modelling RAS . MoscowRussia

The paper presents a finite volume numerical method universally applicable for solving both linear and nonlinear aeroacoustics problems on arbitrary unstructured meshes. It is based on the vertexcentered multi-parameter scheme offering up to the 6th accuracy order achieved on the Cartesian meshes. An adaptive dissipation is added for the numerical treatment of possible discontinuities. The scheme properties are studied on a series of test cases, its efficiency is demonstrated at simulating the noise suppression in resonance-type liners.

关键词： nonlinear aeroacoustics Euler based models finite volume method high accuracy approximation unstructured meshes liners

Ellagic acid induces apoptosis through inhibition of nuclear factor κB in pancreatic cancer cells

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World Journal of Gastroenterology 2008年第23期14卷 3672-3680页

作者： Mouad Edderkaoui Irina Odinokova Izumi Ohno ilya Gukovsky Vay Liang W Go Stephen J Pandol Anna S Gukovskaya Department of Medicine Veterans Affairs Greater Los Angeles Healthcare System and University of CaliforniaLos Angeles CA 90073CaliforniaUnited States Institute of Theoretical and Experimental Biophysics Russian Academy of SciencesPushchinoMoscow Region 142290Russia

AIM： To determine the effect of ellagic acid on apoptosis and proliferation in pancreatic cancer cells and to determine the mechanism of the pro-survival effects of ellagic acid.METHODS： The effect of ellagic acid on apoptosis was assessed by measuring Phosphatidylserine externalization, caspase activity, mitochondrial membrane potential and DNA fragmentation; and proliferation by measuring DNA thymidine incorporation. Mitochondrial membrane potential was measured in permeabilized cells, and in isolated mitochondria. Nuclear factor κB （NF-κB） activity was measured by electromobility shift assay （EMSA）. RESULTS： We show that ellagic acid, a polyphenolic compound in fruits and berries, at concentrations 10 to 50 mmol/L stimulates apoptosis in human pancreatic adenocarcinoma cells. Further, ellagic acid decreases proliferation by up to 20-fold at 50 mmol/L. Ellagic acid stimulates the mitochondrial pathway of apoptosis associated with mitochondrial depolarization, cytochrome C release, and the downstream caspase activation. Ellagic acid does not directly affect mitochondria. Ellagic acid dose-dependently decreased NF-κB binding activity. Furthermore, inhibition of NF-κB activity using IkB wild type plasmid prevented the effect of ellagic acid on apoptosis. CONCLUSION： Our data indicate that ellagic acid stimulates apoptosis through inhibition of the prosurvival transcription factor NF-κB.

关键词： Ellagic acid Nuclear factor-κB Apoptosis Pancreatic cancer

Wootz: Cast Iron or Steel?

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Materials Sciences and Applications 2016年第11期7卷 792-802页

作者： D. A. sukhanov N. V. Plotnikova ASK-MSC Company Moscow Russia Novosibirsk State Technical University Novosibirsk Russia

It is shown that the excess carbide phase in Wootz is of an unusual nature origin that differs from the excess phase of secondary cementite, ledeburite and primary cementite in iron-carbon alloys. It is revealed that the morphological features of excess cementite in Wootz lie in the abnormal size of excess carbides having the shape of irregular prisms. It is discovered that the faceted angular carbides are formed within the original of metastable ledeburite, so they are called “eutectic carbides”. It was found that angular eutectic carbides in the Wootz formed during long isothermal soaking at the annealing and subsequent deformation of ledeburite structures. It is revealed that carbon takes up 2.25% in Wootz (in the region of white cast iron), while none in its structure of crushed ledeburite. It is shown that the pattern of carbide heterogeneity consists entirely of angular eutectic carbides having an irregular trigonal-prismatic morphology. It is shown that Wootz (Damascus steel) is non-alloy tool steel of ledeburite class, similar with structural characteristics of die steel of ledeburite class and high-speed steel, differing from them only in the nature of excess carbide phase.

关键词： Wootz Damascus Steel Bulat Tool Steel

Perspectives on protected area and wildfire management in the Black Sea region

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Journal of Forestry Research 2020年第1期31卷 257-268页

作者： George N.Zaimes Petros A.Tsioras Chrysovalantis Kiosses Mustafa Tufekcioglu Sergiy Zibtsev ilya Trombitsky Razvan Uratu Luiza Gevorgyan Department of Forestry and Natural Environment Management Eastern Macedonia and Thrace Institute of Technology(EMaTTech)1st km Drama66100 MikrohoriouDramaGreece Department of Forestry and Natural Environment Aristotle University of ThessalonikiP.O.Box 22754124 Thessalonı´kiGreece 66100 Choristi DramaGreece Artvin Coruh University ArtvinTurkey National University of Life and Environmental Sciences of Ukraine KievUkraine Eco-TIRAS International Association of River Keepers Chis¸ina˘uRepublic of Moldova Prefect’s Institution of Braila County BrailaRomania Zikatar Environmental Centre Ministry of Nature ProtectionYerevanRepublic of Armenia

Protected areas are necessary for the conservation and enhancement of *** are major threats to forests and other natural areas,because they may cause irreversible *** aim of this study was to analyze the perspective of experts(N=284),from six countries of the Black Sea,on the current status and problems of protected areas and *** their points of view could enhance future management on these issues in the *** collection was carried out for 9 months,using a web-based *** were perceived as a serious problem in Turkey,Armenia and Greece but as a substantially less serious problem in Romania,Ukraine and *** Greece,Armenia,and especially Ukraine,the current designated protected areas are considered sufficient to maintain biodiversity,while in Romania,Turkey,and especially Moldova,more areas should be designated as protected.A major need in all countries(except for Turkey)is the increased use of information and communication technologies for both wildfire suppression and protected area *** were divided on whether wildfire suppression and management of protected areas are ***,there is growing awareness of the adverse impacts of climate change in protected areas and the frequency of wildfires in the *** most frequently suggested measures to alleviate these impacts were:changes in forest management and increasing public awareness for wildfire suppression,along with changes in forest management and increased staff training to enhance protected area conservation.

关键词： Climate change Experts Forested areas Web-based questionnaires

A blind climber:The first evidence of ultrasonic echolocation in arboreal mammals

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Integrative Zoology 2017年第2期12卷 172-184页

作者： Aleksandra A.PANYUTINA Alexander N.KUZNETSOV ilya A.VOLODIN Alexei V.ABRAMOV Irina B.SOLDATOVA Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia Department of Vertebrate Zoology Faculty of BiologyLomonosov Moscow State UniversityMoscowRussia Scientific Research Department Moscow ZooMoscowRussia Zoological Institute Russian Academy of SciencesSaint PetersburgRussia Joint Vietnam-Russian Tropical Research and Technological Centre HanoiVietnam

The means of orientation is studied in the Vietnamese pygmy dormouse Typhlomys chapensis,a poorly known enigmatic semi-fossorial semi-arboreal *** on eye structure are presented,which prove that Typhlomys(translated as“the blind mouse”)is incapable of object vision:the retina is folded and retains no more than 2500 ganglion cells in the focal plane,and the optic nerve is subject to ***,Typhlomys has no other means for rapid long-range orientation among tree branches other than *** vocalization recordings at the frequency range of 50-100 kHz support this *** vocalizations are represented by bouts of up to 7 more or less evenly-spaced and uniform frequency-modulated sweep-like pulses in rapid ***,these sweeps are similar to frequency-modulated ultrasonic echolocation calls of some bat species,but they are too faint to be revealed with a common bat *** recording video simultaneously with the ultrasonic audio,a significantly greater pulse rate during locomotion compared to that of resting animals has been *** findings of locomotion-associated ultrasonic vocalization in a fast-climbing but weakly-sighted small mammal ecotype add support to the“echolocation-first theory”of pre-flight origin of echolocation in bats.

关键词： arboreal locomotion reduced eyes Rodentia Typhlomys ultrasonic echolocation

Density of Vacuum-Like Plasma and Hubble Constant

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Journal of High Energy Physics, Gravitation and Cosmology 2017年第4期3卷 572-587页

作者： ilya A. Obukhov Research & Development Company “System Resources” Moscow Russia

The model in which expansion of the Universe leads to a generation of non-equilibrium vacuum-like electron-positron plasma is proposed and researched. The formulas that relate the Hubble’s constant with the concentration of plasma particles and the cosmological constant are obtained. The collective properties of vacuum-like plasma are investigated. It is shown, that the coefficient of a two-photon annihilation in such plasma is nine times less than for the free particles. A simple formula for dark energy density as a function of electron mass and charge is obtained. It was demonstrated that acceleration of plasma’s chemical potential fluctuations flow proportional of dark energy density.

关键词： Non-Equilibrium Vacuum-Like Plasma Hubble Constant Dark Energy Electron Positron Annihilation Zero Enthalpy

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Nanoporous magnesium

Nano Research 2018年第12期11卷 6428-6435页

作者： ilya Vladimirovich Okulov Sviatlana V.Lamaka Takeshi Wada Kunio Yubuta Mikhail L.Zheludkevich Jorg Weissmuller Jurgen Markmann Hidemi Kato Institute for Materials Research Tohoku UniversityKatahira 2-1-1Sendai980-8577Japan Institute of Materials Research Materials MechanicsHelmholtz-Zentrum Geesthacht21502GeesthachtGermany MagiC-Magnesium Innovation Centre Helmholtz-Zentrum Geesthacht21502GeesthachtGermany Faculty of Engineering University of Kiel24118KielGermany Institute of Materials Physics and Technology Hamburg University of Technology21073HamburgGermany

In this study, we present freestanding nanoporous magnesium as a novel lightweight material with high potential for structural and functional applications. Thus far, the high reactivity of Mg with oxygen and aqueous media prevented the fabrication of nanoporous Mg. First, in order to synthesize nanoporous Mg, we fabricated a bicontinuous nanocomposite consisting of interpenetrating Mg and non-Mg phases by liquid metal dealloying. The non-Mg phases in the nanocomposite protect Mg against corrosion. Second, we etched the non-Mg phases from the nanocomposite, leaving nanoporous Mg, using HF solution. This process is advantageous because the nanoporous Mg was passivated by a MgF2 layer during the etching. Our approach is very flexible, and we demonstrate that versatile microstructures of the nanoporous Mg—e.g., nanoscale bicontinuous network, hierarchical, or plate-like structures—can be designed for the given needs. More importantly, these nanoporous Mg samples can readily be exposed to air without being harmed by corrosion.

关键词： dealloying nanoporous magnesium

Formation of Eutectic Carbides in the Structure of High-Purity White Cast Iron in the Forging Process

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Materials Sciences and Applications 2017年第5期8卷 351-360页

作者： D. A. sukhanov L. B. Arkhangelsky ASK-MSC Company Moscow Russia President Union Smiths Moscow Russia

It is found that the deformation of white cast iron under forging production is only possible with a minimum number of permanent impurities. The developed modes of high-temperature intermediate annealing facilitate the deformation of the forging under normal production conditions. It is shown that in the process of isothermal annealing of white cast iron begins the process of disintegration of ledeburite in the more stable eutectic carbides, providing technological plasticity for subsequent forging. The installed influence of the purity of white cast iron on the morphology of the excess carbides and their ability to divide. Studies the morphology of the excess eutectic carbides after melting, pre-annealing and after deformation forging. Discovered that after severe plastic deformation the structure of white cast iron becomes more stable, due to the appearance of eutectic carbides. It was determined that the deformed structure of white iron, because of its lack ledeburite component, was more identical with the structure of the alloy ledeburite steels. The data obtained can be used for making Damascus bladed weapons products, experiencing shock-variables loads.

关键词： White Cast Iron Damascus steel Wootz Ledeburitic Steel