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Morphology of crater and caldera lakes in the Far Eastern region of Russia and the features of their development

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Journal of Mountain Science 2024年第4期21卷 1246-1258页

作者： dmitrii N.KOZLOv Ekaterina v.LEBEDEvA Institute of Marine Geology and Geophysics Far Eastern Branch of the Russian Academy of SciencesYuzhno-Sakhalinsk 693022Russia Institute of Geography Russian Academy of SciencesMoscow 119017Russia

volcanic lakes in the Kuril-Kamchatka region are difficult to access,and for this reason,they remain poorly studied,with only scattered and brief data *** authors have conducted a study of 10 lake basins using modern digital echolocation survey techniques and have also compiled and summarized published data for 15 lakes in the region,calculating their main morphometric *** has been established that many caldera lake basins are modified by young explosive funnels,extrusive or effusive domes,and exhibit traces of hydrothermal *** lakes of the same genetic type in the Kuril-Kamchatka region are similar in depth and depression forms,the group of caldera lakes shows less homogeneity across all morphometric *** was found that the absolute heights of the reservoirs on Kamchatka Peninsula are generally greater than those on the Kuril Islands,as is often the case with the size of their *** volcanic lakes under study can rapidly change their volume and shape under the influence of endogenous *** the first time for this region,on the base of repeated observations,underwater extrusive dome rate growth and the approximate rates of 2 lake level changes were *** observations of lakes in the Ksudach calderas(Kamchatka)and on Simushir Island indicate approximate rates of level changes:a decrease ranging within 0.5-0.6 m per year(over a 27-year observation interval)and an increase reaching up to 0.26 m per year(over a 48-year interval).The growth rate of the underwater extrusive dome in Lake Shtyubel has averaged 1-1.6 m per year over the past 25 *** analysis has facilitated the first generalization regarding the morphology and developmental features of crater and caldera lakes in the Kuril-Kamchatka region of Russia,representing an important step in their *** results obtained will provide a solid foundation for subsequent research in this region and may be of interest to researchers studying

关键词： volcanic lakes Echolocation survey volcanism Gashydrotherms Kamchatka Kuril Islands

Telluric iron assemblages as a source of prebiotic phosphorus on the early Earth:Insights from Disko Island,Greenland

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Geoscience Frontiers 2024年第5期15卷 415-429页

作者： Oleg S.vereshchagin Maya O.Khmelnitskaya Larisa v.Kamaeva Natalia S.vlasenko dmitrii v.Pankin vladimir N.Bocharova Sergey N.Britvin Saint Petersburg State University University Embankment 7-9St.Petersburg 199034Russia Udmurt Federal Research Center Ural BranchRussian Academy of SciencesIzhevsk 426067Russia Nanomaterial Research Center Kola Science CentreRussian Academy of SciencesApatity 184209Russia

Phosphorus is one of the key elements,which determined the emergence of primordial life on our *** source of prebiotic phosphorus was most likely to be easily soluble compounds containing phosphorus in the negative form of oxidation(e.g.,phosphides).The present paper is the first thorough investigation of phosphide-bearing mineral assemblages confined to telluric(terrestrial)native iron from volcanic rocks of Disko Island,*** speciation in given assemblages varies from the solid solution in native iron(up to 0.3 wt.%P),different phosphides–schreibersite Fe_(3)P,nickelphosphide Ni_(3)P,barringerite Fe_(2)P,and phosphates,including fluorapatite,anhydrous Fe-Na phosphates,phosphoran olivine and pyroxene(up to 1 wt.%P).The diversity of observed phosphorus speciation can be explained by the steep changes of redox conditions during subsurface crystallization of iron-phosphide-bearing *** on the available data on likely redox conditions on the early Earth,we hypothesize that reactive prebiotic phosphorus may have originated from shallow crustal rocks.

关键词： Prebiotic phosphorus Native iron Phosphide Reduced mineral assemblages

Influence of dust particles on spatial distributions of particles and fluxes in positive column of glow discharge

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Plasma Science and Technology 2019年第11期21卷 45-54页

作者： Ruihuan TIAN Chengxun YUAN dmitrii v BOGDANOv Evgeniy A BOGDANOv Anatoly A KUDRYAvTSEv Zhongxiang ZHOU Department of Physics Harbin Institute of TechnologyHarbin 150001People’s Republic of China Faculty of Physics St.Petersburg State University198504St.PetersburgRussia

The research herein examined the results of numerical simulations of the positive column of a glow discharge in argon dusty plasma using COMSOL Multiphysics software under conditions similar to the project known as *** scenarios dealing with formations of spatial distributions of densities and fluxes for charged particles were studied,and evaluations of the influence of dust particles on the discharge were obtained in a wide range of dust *** extreme cases were distinguished:weak dust influence when the densities,fluxes and electric field profiles are not perturbed,and strong dust influence when all three density profiles(electrons,ions and charged dust)in the dust cloud are similar(parallel)to each other,resulting in all created charges in the dust cloud being lost inside the *** such a case,the ambipolar field and the transport of charged particles are decreased in the dust cloud,and any ambipolar flux is almost absent within the cloud.

关键词： dusty plasma glow discharge kinetics modeling scaling laws

Design of bidirectional frictional behaviour for tactile contact using ellipsoidal asperity micro-textures

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Friction 2022年第5期10卷 762-771页

作者： dmitrii SERGACHEv David MATTHEWS Emile vAN DER HEIDE Laboratory for Surface Technology and Tribology Faculty of Engineering TechnologyUniversity of TwenteOverissel 7522 LIWEnschedethe Netherlands Faculty of Engineering and Architecture Ghent UniversitEast Flanders 9000GhenBelgium

Tactile perception and friction can be modified by producing a deterministic surface *** of surface feature arrangement and texture symmetry can produce an anisotropic frictional *** is generally achieved through skin hysteresis by promoting its *** work investigates whether a bidirectional friction can be created with microscale ellipsoidal asperity textures,thus relying on the adhesive component of *** this purpose,four textured samples with various asperity dimensions were moulded with a silicone rubber having an elastic modulus comparable to that of the *** of friction measurements were conducted in-vivo in two sliding directions with a range of normal loads up to 4 *** element method(FEM)was used to study elastic deformation effects,explain the observed friction difference,and predict surface material *** performed perpendicular to the asperity major radii showed consistently higher friction coefficients than that during parallel *** the larger asperity dimensions,a change of the sliding direction increased friction up to a factor of *** numerical analysis showed that this effect is mostly related to elastic asperity *** friction differences can be further controlled by asperity dimensions,spacing,and material properties.

关键词： surface texture sliding direction skin friction elastomer

High frequency of latent Chlamydia trachomatis infection in patients with rhegmatogenous retinal detachment

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International Journal of Ophthalmology(English edition) 2016年第6期9卷 863-868页

作者： Ernest v.Bolko Alexei L.Pozniak dmitrii S.Maltsev Alexei A.Suetov Irina v.Nuralova St.Petersburg Branch of the Academician S.Fyodorov IRTC "Eye Microsurgery"St.Petersburg 192283Russia Department of Ophthalmology Military Medical AcademySt.Petersburg 194044Russia

AIM： To determine the frequency of detection of ocular and extraocular Chlamydia trachomatis （CT） infection in non -high myopes with rhegmatogenous retinal detachment （RRD）. METHODS： This was a single-center, nonrandomized, prospective, case-control study. One hundred and four patients were divided into a study group with RRD （n= 63） and a control group with traumatic retinal detachment （n=41）. Samples of subretinal fluid （SFR）, conjunctival, urethral/cervical swabs, and blood were collected. The frequency of detection of CT infection in SRF samples was determined by polymerase chain reaction （PCR）, direct fluorescence assay （DFA） and cell culture, whereas that in conjunctival swabs was determined by PCR and DFA, and those in urethral/cervical swabs and blood were determined by DFA. Yates Chi-square test （with Bonferroni correction） and two-tailed Student＇s t-test were used for statistical analysis. RESULTS： SRF CT infection was detected more frequently in the study group （50.8%-71.4%） than in the control group （9.8%-12.2%） by all the methods used （P〈 0.01）. The frequency of detection of conjunctival CT infection by DFA was higher in the RRD patients compared with the controls （81.0% vs 24.4%, P=0.004）. The PCR detected conjunctival CT infection more often in the study group than in the controls （46.0% vs89.8%, P= 0.007）. The DFA detected CT in blood specimens almost as frequently as in urogenital specimens, for the RRD patients （61.2% vs 63.5%） and the controls （7.3% vs 9.8%）. CONCLUSION： CT infection is detected with high frequency in non-high myopes with RRD.

关键词： rhegmatogenous retinal detachment Chlamydia trachomatis myopia latent infection

A Short Review: Limnological and Paleolimnological Researches in Mongolia Carried out by Joint Russian-Mongolian Expeditions

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Journal of Mountain Science 2005年第1期2卷 86-90页

作者： dmitrii v.Sevastyanov Nadezhda I.Dorofeyk Dept.Geography & Geoecology Saint-Petersburg State University 10Liniya33St.-Petersburg199178RussiaInstitute of Evolution & EcologyRussian Academy of Sciences Piatnitskaya 47Stroenie3Moscow109017Russia.

Mongolia-extensive inside-continental country,with an area of more than 1,500,000 km2. There are some mountain areas - Hangai and Hantai in the North, and Mongolian Altai in the West, and Gobi Altai - in the Center of... 详细信息

关键词：湖泊学古湖沼学外蒙古俄罗斯阿尔泰山脉

Surgical outcomes in inferior recurrences of rhegmatogenous retinal detachment

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International Journal of Ophthalmology(English edition) 2021年第12期14卷 1909-1914页

作者： Sergey v.Churashov Tatiana N.Shevalova Alexei N.Kulikov dmitrii S.Maltsev Department of Ophthalmology Military Medical AcademySt Petersburg 194044Russia

AIM:To analyze the anatomical and functional outcomes in the inferior recurrences of rhegmatogenous retinal detachment(RRD)depending on the surgical ***:Eighty-one eyes of 81 patients(47 males and 34 females with a mean age of 54.8±14.1y)who demonstrated at least one inferior recurrence of RRD were included in this retrospective *** patients were categorized as having received either circular scleral buckling(SB),pars plana vitrectomy(PPv),a combination of SB and PPv(SB+PPv),PPv with retinotomy(PPv+RT),or PPv+RT and short-term postoperative perfluorocarbon liquid tamponade(PPv+RT+pPFCL).All cases were followed up until successful retinal reattachment or third *** primary outcome measures were the achievement of the surgical goal without recurrence of RRD and bestcorrected visual acuity(BCvA).RESULTS:After the treatment of the first recurrence,the recurrence rate in the PPv+SB group was statistically significantly lower than that of the PPv(P=0.0012),PPv+RT(P=0.028),or PPv+RT+pPFCL(P=0.047)*** was no statistically significant difference between PPv+SB,PPv+RT,and PPv+RT+pPFCL groups in the recurrence rate after treatment of the second recurrence(42 eyes).However,there was a statistically significant(P=0.016)trend towards a decrease of recurrence rate after PPv+RT+*** was no statistically significant improvement of BCvA in either study group(P>0.05)after both first and second recurrence *** mean time follow-up was 109.0±91.0d before the first recurrence and 210.0±186.6d between previous surgery at second ***:Patients with first inferior recurrence of RRD may benefit from SB as an adjunct to *** and short-term pPFCL tamponade in the second recurrence may allow better anatomical outcomes,however,without functional improvement.

关键词： rhegmatogenous retinal detachment pars plana vitrectomy scleral buckling retinotomy recurrence rate

Quantitative tracking of trans-synaptic nose-to-brain transport of nanoparticles and its modulation by odor,aging,and Parkinson’s disease

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Nano Research 2023年第5期16卷 7119-7133页

作者： Alexander v.Romashchenko dmitrii v.Petrovskii Sergey Yu.Trotsky Ksenia N.Morozova Nina B.Illarionova Maria v.Zhukova Elena v.Kiseleva Marina B.Sharapova Daniil S.Zuev Konstantin E.Kuper Sergey Yu.Taskaev Anna I.Kasatova dmitrii A.Kasatov Olga I.Solovieva Ivan A.Razumov Ludmila A.Gerlinskaya Mikhail P.Moshkin Yuri M.Moshkin The Federal Research Center Institute of Cytology and Genetics SB RASAcademician Lavrentiev Avenue10Novosibirsk 630090Russia International tomography center Institutskaya st.3ANovosibirsk 630090Russia G.K.Boreskov Institute of Catalysis SB RASAcademician Lavrentiev Avenue5Novosibirsk 630090Russia The Federal Research Center Budker Institute of Nuclear Physics SB RASAcademician Lavrentiev Avenue11Novosibirsk 630090Russia Institute of Computational Technologies Academician M.A.Lavrentiev avenue6Novosibirsk 630090Russia Institute of Gene Biology Russian Academy of SciencesMoscow 117334Russia Institute of Molecular and Cellular Biology SB RASAcad.Lavrentiev Ave8/2Novosibirsk 630090Russia Federal Research Centre of Biological Systems and Agrotechnologies RASst.January 929Orenburg 460000Russia

Nanoparticles(NPs)can be transported via the nose-to-brain(N_(2)B)***,quantitative data on their spatiotemporal dynamics and regulation of the N_(2)B transport are largely *** surveyed metal oxide/hydroxide NPs as magnetic resonance imaging(MRI)contrasts for quantitative N_(2)B *** containing divalent transition metals were the only ones capable of N_(2)B *** T1-weighted(T1W)MRI,we showed that Mn_(3)O_(4)-NPs were readily engulfed by olfactory receptor neurons(ORNs)without disrupting olfactory sensing,we mapped their N_(2)B *** neurons,the Mn_(3)O_(4)-NPs were localized to the cytosol,mitochondria,vesicles,moved at mixed fast and slow axonal transport velocities intraand extra-vesicularly through *** NPs’axonal transport is dependent on neuronal activity and microtubule *** Mn_(3)O_(4)-NPs were trans-synaptically transmitted through at least four synapses across the olfactory ***-synaptic transmission of the NPs was dependent on N-type Ca^(2+)channels and NMDA receptors but blocked by GABAB receptor activation.A five-parameter Weibull signal increase/decrease model fitted to the T1W MRI data allowed for estimating kinetic parameters of Mn_(3)O_(4)-NP accumulation/*** and relative accumulation rates,but not elimination,correlated negatively with the number of synapses from ORNs,indicating a coupling of the NPs’N_(2)B transport with spontaneous neuronal ***,olfactory stimuli(2,5-dimethylpyrazine and acetophenone)significantly modulated and rerouted the Mn_(3)O_(4)-NP N_(2)B transport odor ***,the NPs’trans-synaptic transmission was impaired by aging and the onset of Parkinson’s *** data suggest new approaches to diagnostics,functional neuroimaging,controlling N_(2)B drug delivery.

关键词： Mn_(3)O_(4)nanoparticles magnetic resonance imaging(MRI) nose-to-brain transport trans-synaptic transmission olfactory stimulation

Development of a methodology for assessing the adequacy of electric power systems

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Global Energy Interconnection 2022年第5期5卷 543-550页

作者： Dmitry S.Krupenev Denis A.Boyarkin dmitrii v.Iakubovskii Melentiev Energy Systems Institute of Siberian Branch of the Russian Academy of Sciences Lermontov str.130Irkutsk664033Russia

This study presents the results of a research into the developing a methodology for assessing the adequacy of advanced electric power systems characterized by the integration of various innovative technologies,which complicates their *** methodology development is aimed at solving two main problems:(1)increase the adequacy of modeling the processes that occur in the electric power system and (2)enhance the computational efficiency of the adequacy assessment *** study proposes a new mathematical model to minimize the power shortage and enhance the adequacy of modeling the *** model considers quadratic power transmission losses and network *** computational efficiency of the adequacy assessment methodology is enhanced using efficient random-number generators to form the calculated states of electric power systems and machine learning methods to assess power shortages and other reliability characteristics in the calculated states.

关键词： Electric power systems Adequacy Power shortage minimization Pseudo-and quasi-random number generation Machine learning methods.