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Struggle zone: alpine shrubs are limited in the Southern Urals by an advancing treeline and insufficient snow depth

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Journal of Forestry Research 2024年第6期35卷 1-12页

作者： Andrey A.Grigoriev vladimir S.Mikryukov Yulia v.Shalaumova Pavel A.Moiseev sergey O.vuykhin Jesús J.Camarero Institute of Plant and Animal Ecology Ural BranchRussian Academy of SciencesSt.8 Marta 202EkaterinburgRussia 6201442 Institute of Ecology and Earth Sciences University of TartuSt.Liivi 250409 TartuEstonia Pyrenean Ecology Institute St.Montañana 100550059 SaragossaSpain

In recent decades,the rapid climate warming in polar and alpine regions has been accompanied by an expan-sion of shrub ***,little is known about how changes in shrub distribution will change as the distribution of tree species and snow cover changes as temperatures *** this work,we analyzed the main environmental factors influencing the distribution and structure of Juniperus sibir-ica,the most common shrub species in the Southern Ural *** mapping and digital elevation models,we demonstrated that *** forms a well-defined vegeta-tion belt mainly between 1100 and 1400 m *** this zone,the abundance and cover of *** are influenced by factors such as rockiness,slope steepness,water regime and tree(Picea obovata)*** analysis of data spanning the past 9 years revealed an upward shift in the distribution of *** with a decrease in its *** primary limit-ing factors for the distribution of *** were the removal of snow cover by strong winter winds and competition with *** a consequence of climatic changes,the tree line and forest limit have shifted upward,further restricting the distribution of *** to higher elevations where com-petition for light with trees is reduced and snow cover is sufficiently deep.

关键词： Juniperaceae Juniperus sibirica Snowpack cover Shrubline Shrub-tree competition Southern Urals Tree line

Self-Assembly and Ordering of C60 on the WO2/W（110） Surface

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Nano Research 2011年第2期4卷 194-203页

作者： sergey A. Krasnikov sergey I. Bozhko Kevin Radican Olaf Lübben Barry E. Murphy Sundar-Raja vadapoo Han-Chun Wu Mohamed Abid valery N. Semenov lgor v. Shvets Centre tbr Research on Adaptive Nanostrucmres and Nanodevices （CRANN） School of Physics Trinity College Dublin Dublin 2 Ireland Institute of Solid State Physics Russian Academy of Sciences Chernogolovka Russian Federation King Abdullah Institute for Nanoteclmology College of Science King Saud University Riyadh 1145l Saudi Arabia

The growth and ordering of C60 molecules on the WO2/W（110） surface have been studied by low-temperature scanning tunnelling microscopy and spectroscopy （STM and STS）, low-energy electron diffraction （LEED）, and density functional theory （DFT） calculations. The results indicate the growth of a well-ordered C60 layer on the WO2/W（110） surface in which the molecules form a close-packed hexagonal structure with a unit cell parameter equal to 0.95 nm. The nucleation of the C60 layer starts at the substrate＇s inner step edges. Low-temperature STM of C60 molecules performed at 78 K demonstrates well-resolved molecular orbitals within individual molecules. In the C60 monolayer on the WO2/W（110） surface, the molecules are aligned in one direction due to intermolecular interaction, as shown by the ordered molecular orbitals of individual C60. STS data obtained from the C60 monolayer on the WO2/W（110） surface are in good agreement with DFT calculations.

关键词： Fullerenes self-assembly tungsten oxide low-temperature scanning tunnelling microscopy scanning tunnellingspectroscopy W(110)

Diclofenac sodium aqueous systems at low concentrations: Interconnection between physicochemical properties and action on hydrobionts

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Journal of Environmental Sciences 2020年第2期32卷 177-186页

作者： Irina S.Ryzhkina Yuliya v.Kiseleva Lyaisan I.Murtazina Tatyana v.Kuznetsova Erik R.Zainulgabidinov Igor v.Knyazev Andrew M.Petrov sergey E.Kondakov Alexander I.Konovalov Arbuzov Institute of Organic and Physical Chemistry FRC Kazan Scientific CenterRussian Academy of Sciences8 Arbuzov str.Kazan 420088Russia Institute for Problems of Ecology and Mineral Wealth Use of Tatarstan Academy of Sciences 28 Daurskaya Str.Kazan 420087Russia Lomonosov Moscow State University Chemistry Dept.1/3 Lenin HillsMoscow 119899Russia

Diclofenac sodium(DS) is a widely used nonsteroidal anti-inflammatory drug(NSAIDs).NSAIDs are poorly removed during standard wastewater *** consequences of the presence of NSAIDs in rivers and lakes at 10-11–10-8 mol/L are not yet established;therefore, ecotoxicologists have focused their efforts on studying the effect of lowconcentration NSAIDs on fish and hydrobionts, and also on predicting the potential risks to *** provides some information about the bioeffects of some NSAID solutions in low concentrations but there is no physicochemical explanation for these *** the physicochemical patterns of DS solutions in the low range of concentrations and establishing an interconnection between the solutions’ physicochemical properties and bioeffects can provide a conceptually new and important source of information regarding the unknown effects of *** physicochemical properties and action of DS solutions on Ceriodaphnia affinis cladocerans,Paramecium caudatum infusoria, Chlorella vulgaris unicellular green algae, as well as on the growth of the roots of Triticum vulgare wheat seeds, were studied in the calculated concentration range of 1 × 10-3–1 × 10-18 mol/*** relationship between these phenomena was established using the certified procedures for monitoring the toxicity of natural water and *** was shown for the first time that water solutions of DS are dispersed systems in which the dispersed phase undergoes a rearrangement with dilution, accompanied by changes in its size and properties, which affects the nonmonotonic dependences of the system’s physicochemical properties and could cause nonmonotonic changes in action on hydrobionts in the low concentration range.

关键词： Diclofenac sodium Low concentration Aqueous solutions Physicochemical properties Hydrobionts Toxicity

Russia’s Peace Initiatives in the MENA Region: Evaluation and Prospects

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Asian Journal of Middle Eastern and Islamic Studies 2019年第4期13卷 534-555,I0004页

作者： sergey v.Kostelyanets Institute for African Studies Russian Academy of SciencesMoscowRussia Department of African and Arab Studies Peoples’Friendship University of RussiaMoscowRussia

Russia’s recent thundering‘return’to the Middle East is first and foremost an obvious result of the effective use of hard power,rather than the tools of soft power such as economics or diplomacy,which played important but secondary *** most visible symbol of this return is the establishment of two permanent sovereign Russian military bases in ***,Moscow has extensive experience in employing hard power to protect its interests,but political,financial and security costs and risks of its application are aplenty,which will dictate Russia’s more cautious policy on this matter in the *** gained a military foothold in the region,Russia now seeks to augment its influence in the MENA region further,and increasingly through the use of soft power,particularly diplomatic *** Astana-Sochi process is the format that Russia has moulded for this *** study seeks to provide,first,an analysis of the Astana-Sochi process for Syria,its theoretical foundations and practical implementations,evaluation of its strengths and weaknesses,and then explore its applicability in the MENA region considering both objective features of the format and more subjective implications of the wider Russian involvement in the region against the backdrop of rising tensions between Moscow and the West.

关键词： Russia peace initiatives the Gulf the Middle East and North Africa conflict resolution

Recent Russian remote sensing investigations in Antarctica within the framework of scientific traverses

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Advances in Polar Science 2015年第2期26卷 113-121页

作者： sergey v.Popov Polar Marine Geosurvey Expedition (PMGE) 24 Pobeda Str.St.-PetersburgLomonosov198412Russia

This paper includes a short historical review of Russian and Soviet scientific traverses to study the Antarctic inland. The first traverse left on April 2, 1956. It resulted in the opening of the first Russian inland research station named Pionerskaya and provided the first geophysical and glaciological data on regions inland of the Antarctic coast. By 1965, a number of regional inland scientific traverses had been completed and. the first Atlas of Antarctica was published in 1966. The atlas presented the main achievements of that time. After the discovery of Lake vostok, Russian scientists commenced remote sensing investigations to study this unique natural phenomenon. The propagation of acoustic and electromagnetic waves in the glacier near vostok Station were measured to provide important geophysical data. Radio-echo sounding data showed that Lake vostok is isolated and separated from the rest of the Antarctic subglacial hydrosphere. The total area of the lake is 15 790 km2, excluding 365 km^2 occupied by 11 islands. Reflection seismic soundings of Lake vostok estimated a total volume of about 6 100 km^3, an average depth of about 400 m, and a maximum depth of 1 200 m. Since 2008, there have been a number of scientific traverses between Mirny and vostok stations and between Progress and vostok stations. The data collected during the traverses have provided new insights into sub-ice topography and ice sheet structure, and have led to the discovery of subglacial lakes near Komsomolskaya Station and under Pionerskaya Station.

关键词： Russian scientific traverses Lake vostok Antarctica remote sensing radio-echo sounding seismic

Symmetry of echinoderms: From initial bilaterally-asymmetric metamerism to pentaradiality

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Natural Science 2014年第4期6卷 171-183页

作者： sergey v. Rozhnov Borissiak Paleontological Institute RAS Moscow Russia

Echinoderm radial symmetry has first appeared in the ambulacral system, when the ambulacral channel assumed the shape of a closed ring or a horseshoe with approximated ends, and then spread onto other organ systems. Its origin was a natural consequence of a steady increase of the original asymmetry of bilaterally-asymmetric three-segmented ancestors of echinoderms, culminated by closing of the ancestral linear metamerism into radiality. The evolutionary transformation from a simple pouchlike hydrocoel with one side channel to an elongated hydrocoel (located under the oesophagus) with two side channels, and finally to a nearly closed horseshoeshaped hydrocoel with three radial channels can be reconstructed based on the theca structure and the number of ambulacra in the row SolutaCincta-Helicoplacoidea. After the hydrocoel with three outbound ambulacral channels circled around the oesophagus as a horseshoe, it either closed into a ring, or its ends became closely approximated. This has determined the primary triradiate symmetry, which quickly transformed into pentaradial symmetry of the 2-1-2 type as a result of branching of two of the three primary radial channels. This occurred no earlier than the Late vendian, when the first bilaterians appeared to have begun to acquire body appendages, and no later than the Early Cambrian, when the first skeletal remains of echinoderms entered the fossil record (in the Atdabanian). The 2-1-2 pentaradial symmetry evolved into the true pentaradiality as a result of shifting the timing of tentacle branching to earlier stages of ontogenesis and even spreading of the five tentacle primordia over the ambulacral ring. This occurred during the Ordovician.

关键词： Echinodermata Symmetry Asymmetry Metamerism Pentaradiality Body Plan Hox Genes Colinearity

Fiber-enriched diet helps to control symptoms and improves esophageal motility in patients with non-erosive gastroesophageal reflux disease

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World Journal of Gastroenterology 2018年第21期24卷 2291-2299页

作者： sergey Morozov vasily Isakov Mariya Konovalova department of Gastroenterology and Hepatology Federal Research Center of NutritionBiotechnologyand Food SafetyMoscow 115446Russia

AIM To investigate the effect of dietary fiber on symptoms and esophageal function testing parameters in nonerosive gastroesophageal reflux disease(GERD)(NERD) *** Thirty-six NERD patients with low(vailable to the final analysis. The obtained results were analyzed with the use of non-parametric statistics(Wilcoxon matched pairs test). RESULTS The number of patients experiencing heartburn was less(93.3% at baseline vs 40% at the end of the study, P vs 6.0 ± 2.3, P < 0.001) after the treatment period. Minimal resting lower esophageal sphincter(LES) pressure increased from 5.41 ± 10.1 to 11.3 ± 9.4 mm Hg(P = 0.023), but no change in residual LES pressure and mean resting pressure was found. Total number of gastroesophageal refluxes(GER) decreased from 67.9 ± 17.7 to 42.4 ± 13.5(P < 0.001) predominantly by acid and weak acid types of GERs. No significant change in mean esophageal p H and % of time p H < 4 was registered. Maximal reflux time decreased from 10.6 ± 12.0 min to 5.3 ± 3.7 min(P < 0.05). CONCLUSION Fiber-enriched diet led to a significant increase of minimal lower esophageal sphincter resting pressure, a decrease of number of gastroesophageal refluxes, and a decrease of heartburn frequency per week in NERD.

关键词： gastroesophageal reflux disease psyllium gastroesophageal reflux lower esophageal sphincter relaxation esophageal motility Dietary fiber heartburn non-erosive gastroesophageal reflux disease

Distribution and Status of the Pallas’s Gull Ichthyaetus ichthyaetus(Pallas,1773)in the Reservoirs of the Palearctic:Review

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Research in Ecology 2023年第1期5卷 23-34页

作者： sergey vladimirovich Golubev Fish Ecology Laboratory Papanin Institute for Biology of Inland WatersRussian Academy of SciencesBorok152742Russia

The Pallas’s Gull Ichthyaetus ichthyaetus is a piscivorous gull,some local populations of which are rare and *** review presents data on the status and distribution of the Pallas’s Gull in the reservoirs of the Palearctic-water bodies in which the water level is controlled by *** aim of the study was to assess the current state of the species in the reservoirs of the *** review was based on 1080 publications found in the search engines Yandex,Google,Google Scholar,*** the last 35 years,the Pallas’s Gull has been found in 63 reservoirs of the *** has been established in 11 reservoirs,breeding has not been established in 43 reservoirs,and birds were present in 9 reservoirs,but the status was not ***-thirds of the reservoirs where the gull was recorded or bred were located in the European part and only 1/3 in *** is assumed that up to 5000 adults(0.45%-4.0%of the global population of the species)breed annually in the reservoirs of the Palearctic,and the reservoirs are not the main habitats for maintaining and reproducing the population of the *** majority of the breeding population reproduces in natural water bodies,and the reservoirs of the Palearctic are important for the maintenance of non-breeding *** of presumed breeding and new breeding colonies in reservoirs north of the historical range of the species has been established on the Russian Plain,in the Urals and *** reservoirs of Russia play a leading role in providing breeding sites for the species in water bodies of this *** analysis of the data allows us to state the important and increased role of reservoirs in the modern distribution and expansion of the range of the Pallas’s Gull in the Palearctic.

关键词： Great Black-headed Gull Damming

Determination of Iron in Water Solution by Time-Resolved Femtosecond Laser-Induced Breakdown Spectroscopy

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Plasma Science and Technology 2015年第11期17卷 975-978页

作者： sergey S.GOLIK Alexey A.ILYIN Michael Yu.BABIY Yulia S.BIRYUKOvA vladimir v.LISITSA Oleg A.BUKIN Far Eastern Federal University Institute of Automation and Control Processes Far Eastern BranchRussian Academy of Sciences

The influence of the energy of femtosecond laser pulses on the intensity of Fe I （371.99 nm） emission line and the continuous spectrum of the plasma generated on the surface of Fe^3＋ water solution by a Ti： sapphire laser radiation with pulse duration 〈45 fs and energies up to 7 mJ is determined. A calibration curve was obtained for Fe3＋ concentration range from 0.5 g/L to the limit of detection in water solution, and its saturation was detected for concentrations above 0.25 g/L, which is ascribed to self-absorption. The 3σ- limit of detection obtained for Fe in water solution is 2.6 mg/L in the case of 7 mJ laser pulse energy. It is found that an increase of laser pulse energy insignificantly affects on LOD in the time-resolved LIBS and leads to a slight improvement of the limit of detection.

关键词： femtosecond laser-induced breakdown spectroscopy LIBS femtosecond plasma iron analysis of water atomic emission spectroscopy limit of detection