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Long-term Speckle Interferometric Monitoring of Binary Systems:2007–2023Positional Measurements and Orbits of Seven Objects

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Research in Astronomy and Astrophysics 2024年第9期24卷 147-155页

作者： Arina Mitrofanova Vladimir Dyachenko Anatoly Beskakotov yuri Balega Alexander Maksimov Denis Rastegaev Special Astrophysical Observatory 369167 Nizhnij ArkhyzRussia

The results of seventeen years of speckle interferometric monitoring of seven objects(Chara 122Aa,GJ 3010,HIP1987,GJ 3076,HIP 11253,HIP 11352,and HIP 14929)are *** data were obtained at the 6 m Big Telescope Alt-azimuthal Special Astrophysical Observatory of the Russian Academy of Science(BTA SAO RAS)from 2007 to the *** of previously published and new measurements made it possible to construct completely new orbits for Chara 122Aa,HIP 11253,and HIP *** orbit of GJ 3076 cannot be constructed accurately due to the large influence of the weights assigned to the *** resulting orbital solutions are classified based on a grading scheme suggested by ***,*** and ***;most orbits are“definitive”(Grade 1).The mass sums and masses of components calculated by two independent methods using Hipparcos and Gaia DR2 and DR3 parallaxes were compared for the objects under study.

关键词： techniques:high angular resolution (stars:)binaries:visual stars:fundamental parameters stars:low-mass stars:solar-type

Electrical triggering of earthquakes:results of laboratory experiments at spring-block models

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Earthquake Science 2017年第4期30卷 167-172页

作者： Victor A.novikov Vladimir I.Okunev Vadim n.Klyuchkin Jing Liu yuri Ya.Ruzhin Xuhui Shen Joint Institute for High Temperatures of Russian Academy of Sciences MoscowRussia Institute of Earthquake Science China Earthquake AdministrationBeijingChina Pushkov Institute of Terrestrial Magnetism and Radio Wave Propagation TroitskMoscow RegionRussia Institute of Crustal Dynamics China Earthquake AdministrationBeijingChina

Recently published results of field and laboratory experiments on the seismic/acoustic response to injection of direct current （DC） pulses into the Earth crust or stressed rock samples raised a question on a possibility of electrical earthquake triggering. A physical mechanism of the considered phenomenon is not clear yet in view of the very low current density （10-7-10-s A/m^2） generated by the pulsed power systems at the epicenter depth （5-10 km） of local earthquakes occurred just after the current injection. The paper describes results of laboratory ＂earthquake＂ triggering by DC pulses under conditions of a spring-block model simulated the seismogenic fault. It is experimentally shown that the electric triggering of the laboratory ＂earthquake＂（sharp slip of a movable block of the spring-block system） is possible only within a range of subcritical state of the system, when the shear stress between the movable and fixed blocks obtains 0.98-0.99 of its critical value. The threshold of electric triggering action is about 20 A/m^2 that is 7-8 orders of magnitude higher than estimated electric current density for Bishkek test site （northern Tien Shan, Kirghizia） where the seismic response to the man-made electric action was observed. In this connection, the electric triggering phenomena may be explained by contraction of electric current in the narrow conductive areas of the faults and the corresponding increase in current density or by involving the secondary triggering mechanisms like electromagnetic stimulation of conductive fluid migration into the fault area resulted in decrease in the fault strength properties.

关键词： Earthquake simulation Spring-block model Electric pulse Triggering threshold

Applications of two electric arc plasma torches for the beneficiation of natural quartz

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International Journal of Minerals,Metallurgy and Materials 2019年第3期26卷 267-273页

作者： yuri-Mikhailovich Grishin Long Miao Lev-Alekseevich Borisov nikolay-Mikhailovich Serykh Alexey-yurievich Kulagin Department of Thermal physics Bauman Moscow State Technical University Federal State Unitary Enterprise Tsentrkvarts

Experimental beneficiation processes of quartz concentrate in arc plasma torches of two different types and electric powers were studied. An emission scanning electron microscope and a universal laser analyzer were used to investigate the structures as well as the size distributions of grains and microparticles. Inductively coupled plasma–mass spectrometry was used to determine the chemical compositions of nonstructural solid-phase mineral impurities in quartz concentrate. Results related to the modified grains' structure and size distribution, the compositions of impurities, and the gas–liquid inclusions in the quartz concentrate were investigated. The total impurities concentrations in the processed grains were found to satisfy the IOTA-STD standard(industry standard for grading high quality fused quartz products). The optimal condition(i.e., the optimal specific plasma enthalpy) for the production of high-purity quartz in arc plasma torches was found to depend on the geological-genetic type and the structural and textural features(i.e., chemical composition and gas–liquid inclusions) of the quartz concentrate.

关键词： low-temperature plasma beneficiation high purity quartz arc plasma torch IOTA-STD standard

Update on the pathological roles of prostaglandin E_(2) in neurodegeneration in amyotrophic lateral sclerosis

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Translational neurodegeneration 2023年第1期12卷 464-478页

作者： Hiroshi nango Komugi Tsuruta Hiroko Miyagishi yuri Aono Tadashi Saigusa Yasuhiro Kosuge Laboratory of Pharmacology School of PharmacyNihon University7-7-1 NarashinodaiFunabashi-ShiChiba 274-8555Japan Department of Pharmacology School of Dentistry at MatsudoNihon University2-870-1 SakaechonishiMatsudo-ShiChiba 271-8587Japan

Amyotrophic lateral sclerosis(ALS)is a progressive neurodegenerative disease characterized by selective degeneration of upper and lower motor *** pathogenesis of ALS remains largely unknown;however,inflammation of the spinal cord is a focus of ALS research and an important pathogenic process in *** E_(2)(PGE_(2))is a major lipid mediator generated by the arachidonic-acid cascade and is abundant at inflammatory ***_(2)levels are increased in the postmortem spinal cords of ALS patients and in ALS model *** therapeutic effects have been obtained in ALS model mice using cyclooxygenase-2 inhibitors to inhibit the biosynthesis of PGE_(2),but the usefulness of this inhibitor has not yet been proven in clinical *** this review,we present current evidence on the involvement of PGE_(2)in the progression of ALS and discuss the potential of microsomal prostaglandin E syn-thase(mPGES)and the prostaglandin receptor E-prostanoid(EP)2 as therapeutic targets for *** pathways involving prostaglandin receptors mediate toxic effects in the central nervous *** some situations,however,the receptors mediate neuroprotective *** recent studies demonstrated that levels of mPGES-1,which catalyzes the final step of PGE_(2)biosynthesis,are increased at the early-symptomatic stage in the spinal cords of transgenic ALS model mice carrying the G93A variant of superoxide *** addition,in an experimental motor-neuron model used in studies of ALS,PGE_(2)induces the production of reactive oxygen species and subsequent caspase-3-de-pendent cytotoxicity through activation of the EP2 ***,this PGE_(2)-induced EP2 up-regulation in motor neurons plays a role in the death of motor neurons in ALS model *** understanding of the pathophysiologi-cal role of PGE_(2)in neurodegeneration may provide new insights to guide the development of novel therapies for ALS.

关键词： Prostaglandin E_(2) Amyotrophic lateral sclerosis Motor neuron death E-prostanoid receptor Microsomal prostaglandin E synthetase-1

Machine perfusion of the liver: Which is the best technique to mitigate ischaemia-reperfusion injury?

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World Journal of Transplantation 2019年第1期9卷 14-20页

作者： yuri L Boteon Simon C Afford Liver Unit Queen Elizabeth HospitalUniversity Hospitals Birmingham NHS Foundation Trust Centre for Liver and Gastrointestinal Research Institute of Immunology and ImmunotherapyCollege of Medical and Dental SciencesUniversity of Birmingham national Institute for Health Research (nIHR) Birmingham Biomedical Research Centre University of Birmingham and University Hospitals Birmingham NHS Foundation Trust

Longstanding research describes the mechanisms whereby the restoration of blood flow and reoxygenation(reperfusion) aggravates the ischaemic injury caused by a period of anoxia to a donor liver. This phenomenon, called ischaemia-reperfusion injury(IRI), leads to parenchymal cell death,microcirculatory failure, and inflammatory immune response. Clinically, IRI is the main factor responsible for the occurrence of posttransplant graft dysfunction and ischaemic-type biliary lesions. While extended criteria donor livers are more vulnerable to IRI, their utilisation is required to address the shortfall in donor organs. Thus, the mitigation of IRI should drive the setting of a new benchmark for marginal organ preservation. Herein, strategies incorporating different modalities of machine perfusion of the liver to alleviate IRI are discussed in conjunction with advantages and disadvantages of individual *** leading to reperfusion of the liver during machine perfusion(in situ normothermic regional perfusion and ex situ normothermic machine perfusion)may mitigate IRI by shortening the ischaemic period of the organs. This benefit potentially escalates from the minimum level, obtained following just partial alleviation of the ischaemic period, to the maximum level, which can be potentially achieved with ischaemia-free organ transplantation. Techniques that do not lead to reperfusion of the liver during machine perfusion(hypothermic,subnormothermic, and controlled-oxygenated rewarming) optimise mitochondrial oxidative function and replenish cellular energy stores, thereby lowering reactive oxygen species production as well as the activation ofdownstream inflammatory pathways during reperfusion. Further mechanistic insights into IRI may guide the development of donor-specific protocols of machine perfusion on the basis of the limitations of individual categories of extended criteria donor organs.

关键词： Machine perfusion of the liver Ischaemia-reperfusion injury Liver transplantation Organ preservation Organ reconditioning

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The Jewish century

The Jewish century

Mollisols Properties and Changes in Ukraine and China

作者： yuri Slezkine.

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Chinese Geographical Science 2011年第3期21卷 257-266页

作者： yuri S KRAVCHEnKO ZHAnG Xingyi LIU Xiaobing SOnG Chunyu Richard M CRUSE Key Laboratory of Mollisols Agroecology Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Harbin 150081 China national University of Life and Environmental Sciences of Ukraine Kyiv 03041 Ukraine Department of Agronomy Iowa State University Ames 500011 IA USA

Soils are the foundation of civilizations and the basis for human food *** in Ukraine and northeast China are two out of the four major Mollisol regions in the *** natural areas from which Mollisols developed are the prairies and steppes that experience temperate and freezing *** review paper introduces the general climate,vegetation,and topography of Mollisols regions in Ukraine and northeast China,analyzes their properties,including soil texture,soil organic matter content,soil bulk density,pH,cation exchange capacity and other chemical properties,and compares the property changes and management practices of Mollisols in relation to sustainable grain production.

关键词： Mollisols soil properties soil organic matter tillage Mollisols management

Fracture network characterisation of the Balmuccia peridotite using drone-based photogrammetry,implications for active-seismic site survey for scientific drilling

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第10期16卷 3961-3981页

作者： niccolo Menegoni yuri Panara Andrew Greenwood Davide Mariani Alberto Zanetti Gyorgy Hetenyi Ali I.Al-naimi Petroleum Engineering Research Center King Abdullah University of Science and TechnologyThuwal23955-6900Saudi Arabia Chair of Applied Geophysics Montanuniversit€at LeobenLeobenAustria Department of Earth and Environmental Sciences University of PaviaPaviaItaly Institute of Geosciences and Earth Resources National Research Council(IGG-CNR)PaviaItaly Institute of Earth Sciences University of Lausanne1015LausanneSwitzerland

The presence of discontinuities(***,fractures,veins,layering)in crystalline rocks can be challenging for seismic interpretations because the wide range of their size,orientation,and intensity,which controls the mechanical properties of the rock and elastic wave propagation,resulting in equally varying seismic responses at different *** geometrical characterisation of adjacent outcrop discontinuity networks allows a better understanding of the nature of the subsurface rocks and aids seismic *** this study,we characterise the discontinuity network of the Balmuccia peridotite(BP)in the IvreaeVerbano Zone(IVZ),northwestern *** geological body is the focus of the Drilling the Ivrea eVerbano zonE(DIVE),an international continental scientific drilling project,and two active seismic surveys,SEismic imaging of the Ivrea ZonE(SEIZE)and high-resolution SEIZE(Hi-SEIZE),which aim to resolve the subsurface structure of the DIVE drilling target through high-resolution seismic *** fracture characterisation,we developed two drone-based digital outcrop models(DOMs)at two different resolutions(10^(-3)-10 m and 10^(-1)-10^(3)m),which allowed us to quantitatively characterise the orientation,size,and intensity of the main rock *** properties affect the seismic velocity and consequently the interpretation of the seismic *** found that(i)the outcropping BP discontinuity network is represented by three more sets of fractures with respect to those reported in the literature;(ii)the discontinuity sizes follow a power-law distribution,indicating similarity across scales,and(iii)discontinuity intensity is not uniformly distributed along the *** results help to explain the seismic behaviour of the BP detected by the SEIZE survey,suggesting that the low P-wave velocities observed can be related to the discontinuity network,and provide the basic topological parameters(orientation,density,distribution,and aperture)of the frac

关键词： Remote sensing Fracture intensity Digital outcrop model(DOM) Rock discontinuity Fault SEismic imaging of the Ivrea ZonE(SEIZE) IvreaeVerbano Zone(IVZ) Crystalline rock

numerical Simulation of Blood Flow in Aorta with Dilation:A Comparison between Laminar and LES Modeling Methods

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Computer Modeling in Engineering & Sciences 2020年第8期124卷 509-526页

作者： Lijian Xu Tianyang Yang Lekang Yin Ye Kong yuri Vassilevski Fuyou Liang School of naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Shanghai Chest Hospital Shanghai Jiao Tong UniversityShanghai200030China Zhongshan Hospital Fudan UniversityShanghai200032China Marchuk Institute of numerical Mathematics Russian Academy of SciencesMoscow119333Russia Institute for Personalized Medicine Sechenov UniversityMoscow119991Russia Key Laboratory of Hydrodynamics(Ministry of Education) Shanghai Jiao Tong UniversityShanghai200240China

Computational modeling methods have been increasingly employed to quantify aortic hemodynamic parameters that are challenging to in vivo measurements but important for the diagnosis/treatment of aortic *** the presence of turbulence-like behaviors of blood flow in normal or diseased aorta has long been confirmed,the majority of existing computational model studies adopted the laminar flow assumption(LFA)in the treatment of sub-grid flow *** far,it remains unclear whether LFA would significantly compromise the reliability of hemodynamic *** the present study,we addressed the issue in the context of a specific aortopathy,namely aortic dilation,which is usually accompanied by disturbed flow *** patient-specific aortas with treated/untreated dilation of the ascending segment were investigated,and their geometrical models were reconstructed from computed tomography angiographic images,with the boundary conditions being prescribed based on flow velocity information measured in vivo with the phase contrast magnetic resonance imaging *** the modeling of blood flow,apart from the traditional LFA-based method in which sub-grid flow dynamics is ignored,the large eddy simulation(LES)method capable of incorporating the dissipative energy loss induced by turbulent eddies at the sub-grid level,was adopted and taken as a reference for examining the performance of the LFA-based *** results showed that the simulated large-scale flow patterns with the two methods had high similarity,both agreeing well with in vivo measurements,although locally large between-method discrepancies in computed hemodynamic quantities existed in regions with high intensity of flow ***,a switch from the LES to the LFAbased modeling method led to mild(nges in computed space-averaged wall shear stress metrics(i.e.,SA-TAWSS,SA-OSI)in the ascending aortic segment where intensive vortex evolution accompanied by high stat

关键词： Blood flow aortic dilation computational modeling turbulence laminar flow assumption large eddy simulation