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Hidden stage of intracranial hemorrhage in newborn rats studied with laser speckle contrast imaging and wavelets

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Journal of Innovative Optical Health Sciences 2015年第5期8卷 99-106页

作者： Alexey n.Pavlov Arkady S.Abdurashitov Olga n.Pavlova Valery V.Tuchin Olga S.Sindeeva sergey S.Sindeev Oxana V.Semyachkina-Glushkovskaya Department of Physics Saratov State University 83 Astrakhanskaya Str.Saratov 410012Russia Department of Biology Saratov State University 83 Astrakhanskaya Str.Saratov 410012Russia

Using the laser speckle contrast imaging and wavelet-based analyses,we investigate a latent("hidden")stage of the development of intracranial hemorrhages(ICHs)in newborn *** apply two measures based on the continuous wavelet-transform of blood flow velocity in the sagittal sinus,namely,the spectral energy in distinct frequency ranges and a multiscality degree characterizing complexity of experimental *** show that the wavelet-based multifractal formalism reveals changes in the cerebrovascular blood flow at the development of ICH.

关键词： Cerebral blood flow laser speckle contrast imaging stress wavelet-analysis complexity

Structure-property relationships in ILs: A study of the alkyl chain length dependence in vaporisation enthalpies of pyridinium based ionic liquids

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Science China Chemistry 2012年第8期55卷 1525-1531,1-6页

作者： ZAITSAU Dzmitry H. YERMALAYEU Andrei V. EMEL'YAnEnKO Vladimir n. VEREVKIn sergey P. WELZ-BIERMAnn Urs SCHUBERT Thomas Department of Physical Chemistry University of Rostock Dr-Lorenz-Weg 1 D-18059 Rostock Germany Evonik Degussa Taiwan Ltd. 133 Minsheng East Road Section Taipei 10596 China 3IoLiTec Ionic Liquids Technologies GmbH Salzstrasse 184 74076 Heilbronn Germany

The enthalpies of vaporization for the series of pyridinium-based ionic liquids with bis（trifluoromethylsulfonyl）imide anion [CnPy][nTfz] （n = 2, 3, 4, 5, and 6） have been determined with the quartz crystal microbalance technique combined with the Langmuir evaporation. The linear dependence of vaporization enthalpies on the chain length has been revealed. new approach based on volumetric, surface tension, and speed of sound measurements has been developed for estimation of heat capacity differences between gas and liquid phase, which were required for adjustment of measured vaporization enthalpies to the ref- erence temperature 298 K.

关键词： ionic liquids enthalpy of vaporization quartz crystal microbalance structure-property relations

Accounting for natural-climatic conditions in the design of roads in western Siberia

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Research in Cold and Arid Regions 2015年第4期7卷 307-315页

作者： Vladimir n.Efimenko sergey V.Efimenko Alexey V.Sukhorukov Tomsk State University of Architecture and Building

The paper proposes a methodological scheme that thoroughly accounts for natural-climatic conditions which can impair the stability and longevity of transport facilities （roadways）, to ensure the best possible quality of the initial road design. Factors determining the formation of water-heating mode subgrade soils are allocated, and an information database for mathematical modeling of geocomplexes is shown. Values of strength and deformability of clay soils are calculated within the limits of the defined, homogeneous road districts in Western Siberia to provide the required level of reliability of design solutions.

关键词： transport facilities road-climatic zoning water-heating mode subgrade soils design geocomplexes

Impulse magnetic stimulation facilitates synaptic regeneration in rats following sciatic nerve injury

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neural Regeneration Research 2012年第17期7卷 1299-1303页

作者： sergey A.Zhivolupov Miroslav M.Odinak nariman A.Rashidov Ludmila S.Onischenko Igor n.Samartsev Anton A.Jurin Department of neurology Military-Medical AcademySaint-Petersburg194044Lesnoy prospect 2Russian Federation

The current studies describing magnetic stimulation for treatment of nervous system diseases mainly focus on transcranial magnetic stimulation and rarely focus on spinal cord magnetic stimulation. Spinal cord magnetic stimulation has been confirmed to promote neural plasticity after injuries of spinal cord, brain and peripheral nerve. To evaluate the effects of impulse magnetic stimulation of the spinal cord on peripheral nerve regneration, we compressed a 3 mm segment located in the middle third of the hip using a sterilized artery forceps to induce ischemia. Then, all animals underwent impulse magnetic stimulation of the lumbar portion of spinal crod and spinal nerve roots daily for 1 month. Electron microscopy results showed that in and below the injuryed segment, the inflammation and demyelination of neural tissue were alleviated, apoptotic cells were reduced, and injured Schwann cells and myelin fibers were repaired. These findings suggest that high-frequency impulse magnetic stimulation of spinal cord and corresponding spinal nerve roots promotes synaptic regeneration following sciatic nerve injury.

关键词： impulse magnetic stimulation experimental neuropathy sciatic nerve lesion neuroplasticity neuralregeneration

Partnership for eXtreme Xtallography (PX^(2))—A state-of-the-art experimental facility for extreme-conditions crystallography: A case study of pressure-induced phase transition in natural ilvaite

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Matter and Radiation at Extremes 2022年第2期7卷 62-71页

作者： Jingui Xu Dongzhou Zhang sergey n.Tkachev Przemyslaw K.Dera School of Ocean and Earth Science and Technology Hawai’i Institute of Geophysics and PlanetologyUniversity of Hawai’i at ManoaHonoluluHawaii 96822USA Center for Advanced Radiation Sources University of ChicagoChicagoIllinois 60437USA

Single-crystal x-ray diffraction(SCXRD)is an important tool to study the crystal structure and phase transitions of crystalline materials at elevated *** Partnership for eXtreme Xtallography(PX^(2))program at the GSECARS 13-BM-C beamline of the Advanced Photon Source aims to provide state-of-the-art experimental capabilities to determine the crystal structures of materials under extreme conditions using ***^(2) provides a focused x-ray beam(12318μm^(2))at a monochromatic energy of 28.6 ***-pressure SCXRD experiments are performed with a six-circle diffractometer and a Pilatus3 photon-counting detector,facilitated by a membrane system for remote pressure control and an online ruby fluorescence system for pressure *** efficient,high-quality crystal structure determination at PX^(2) is exemplified by a study of pressure-induced phase transitions in natural ilvaite[CaFe^(2+)_(2 )Fe^(3+)Si_(2)O_(7)O(OH),P2_(1)/a space group].Two phase transitions are observed at high *** SCXRD data confirm the already-known ilvaite-I(P2_(1)/a)→ilvaite-II(Pnam)transformation at 0.4(1)GPa,and,a further phase transition is found to occur at 22.8(2)GPa where ilvaite-II transforms into ilvaite-III(P2_(1)/a).The crystal structure of the ilvaite-III is solved and refined in the P2_(1)/a space *** addition to the ilvaite-I→ilvaite-II→ilvaite-III phase transitions,two minor structural modifications are observed as discontinuities in the evolution of the FeO6 polyhedral geometries with pressure,which are likely associated with magnetic transitions.

关键词： phase extreme transitions

Strain control of layer-resolved negative capacitance in superlattices

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npj Computational Materials 2020年第1期6卷 127-130页

作者： Raymond Walter sergey Prosandeev Charles Paillard L.Bellaiche Department of Physics and Institute for nanoscience and Engineering University of ArkansasFayettevilleAR 72701USA Department of Mathematical Sciences University of ArkansasFayettevilleAR 72701USA Identity Engineering Kinesso LLCConwayAR 72032USA Institute of Physics and Physics Department of Southern Federal University Rostov-na-Donu 344090Russia Laboratoire Structures Propriétés et Modélisation des SolidesCentraleSupélecUMR CNRS 8580UniversitéParis-Saclay91190 Gif-sur-YvetteFrance

negative capacitance in BaTiO_(3)/SrTiO_(3) superlattices is investigated by Monte Carlo simulations in an atomistic effective Hamiltonian model,using fluctuation formulas for responses to the local macroscopic field that incorporates depolarizing *** show that epitaxial strain can tune the negative capacitance of the BaTiO_(3) ferroelectric layer and the overall capacitance of the *** addition,we predict and explain an original switching of the negative capacitance from the BaTiO3 layer to the SrTiO_(3) layer at low temperatures for intermediate strains.

关键词： capacitance layer resolved

Pulsating magneto-dipole radiation of a quaking neutron star powered by energy of Alfvn seismic vibrations

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Research in Astronomy and Astrophysics 2011年第9期11卷 1085-1092页

作者： sergey Bastrukov Jun-Wei Yu Ren-Xin Xu Irina Molodtsova State Key Laboratory of nuclear Physics and Technology School of Physics Peking University Beijing 100871 China Joint Institute for nuclear Research 141980 Dubna Russia

We compute the characteristic parameters of the magneto-dipole radiation of a neutron star undergoing torsional seismic vibrations under the action of Lorentz restoring force about an axis of a dipolar magnetic field experiencing decay. After a brief outline of the general theoretical background of the model of a vibration-powered neutron star, we present numerical estimates of basic vibration and radiation characteristics, such as frequency, lifetime and luminosity, and investigate their time dependence on magnetic field decay. The presented analysis suggests that a gradual decrease in frequencies of pulsating high-energy emission detected from a handful of currently monitored AXP/SGR-like X-ray sources can be explained as being produced by the vibration-powered magneto-dipole radiation of quaking magnetars.

关键词： neutron stars -- torsion Alfv6n vibrations -- vibration powered radiation -- magnetic field decay -- magnetars

Investigation of radio pulsar emission features using power spectra

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Research in Astronomy and Astrophysics 2018年第8期18卷 63-70页

作者： Valery M.Malofeev sergey A.Tyul'bashev En.Lebedev Physical Institute of the Russian Academy of Sciences V.V.Vitkevich Pushchino Radio Astronomy ObservatoryPRAO ASC FIANPushchinoRussia

Since 2013, round-the-clock monitoring of the sky has been carried out simultaneously in 96 beams using a high-sensitivity radio telescope called the Large Phased Array （LPA） at the frequency 110.25 MHz. These observations are made under the program of interplanetary plasma investigation. The same data are used to search for pulsars by means of power spectra. To increase the sensitivity of the pulsar search, 500-600 power spectra corresponding to different days of observations are summed. In the integrated spectra of known pulsars, besides expected improvement in signal-to-noise （S/n） ratio for the frequency harmonics, some features are explored in this paper. We present the 27 strongest pulsars which are in a field with declination 21° - 42°. The observable details in the integrated power spectra are connected with the presence of pulsar periods of the second （P2） and third （P3） class, which have been identified. Empirical relations for calculating these periods are obtained. The value P2 is estimated for 26 pulsars, and for 15 sources it is made for the first time. The value P3 is estimated for 13 pulsars, among them these values are given for five sources for the first time.

关键词： pulsars general - pulsars

Modern problems of aircraft aerodynamics

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Advances in Aerodynamics 2019年第1期1卷 145-159页

作者： sergey L.Chernyshev sergey V.Lyapunov Andrey V.Wolkov Department of Aerodynamics Central Aerohydrodynamic Institute named after Prof.N.EZhukovsky(TsAGI)140180Zhukovsky str.1ZhukovskyRussia

The article represents the discussion of several separate directions of investigations,which are performed by TsAGI flight vehicles aerodynamics specialists at the *** are some major trends of classical layout of route aircraft and also peculiarities of some prospective flight *** there are some hypersonic vehicles aerodynamics questions examined along with problems of creation of civil supersonic transport *** is a description given for well-known and some newer methods of flow control for drag reduction.

关键词： Aircraft aerodynamics Hypersonic vehicles aerodynamics Civil supersonic transport aircraft Sonic boom