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Climate change evidence in tree growth and stand productivity at the upper treeline ecotone in the Polar Ural Mountains

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Forest Ecosystems 2020年第1期7卷 76-91页

作者： Nadezhda M.Devi vladimir v.kukarskih Аrina A.Galimova valeriy S.Mazepa Andrey A.Grigoriev Institute of Plant and Animal Ecology Ural BranchRussian Academy of Sciences8 Marta202/3Ekaterinburg 620144Russia

Background:Recent warming is affecting species composition and species areal distribution of many ***,although most treeline studies have estimated the rates of forest expansion into tundra,still little is known about the long-term dynamic of stand productivity at the forest-tundra ***,we make use of tree-ring data from 350 larch(Larix sibirica Ledeb.)and spruce(Picea obovata Ledeb.)sampled along the singular altitudinal treeline ecotone at the Polar Urals to assess the dynamic of stand establishment and productivity,and link the results with meteorological observations to identify the main environmental ***:The analysis of stand instalment indicated that more than 90%of the living trees appeared after *** this period,the stand became denser and moved 50m upward,while in recent decades the trees of both species grew *** maximum afforestation occurred in the last decades of the twentieth century,and the large number of encountered saplings indicates that the forest is still *** upward shift coincided with a slight increase of May-August and nearly doubling of September-April precipitation while the increase in growth matched with an early growth season warming(June+0.27°C per decade since 1901).This increase in radial growth combined with the stand densification led to a 6-90 times increase of biomass since ***:Tree-ring based twentieth century reconstruction at the treeline ecotone shows an ongoing forest densification and expansion accompanied by an increased *** changes are driven by climate change mechanism,whereby the leading factors are the significant increase in May-June temperatures and precipitation during the dormant *** of phytomass accumulation mechanisms within treeline ecotone is valuable for improving our understanding of carbon dynamics and the overall climate balance in current treeline ecosystems and for predicting how these will be altered by global ch

关键词： Polar Urals Treeline Productivity Climate change Radial growth Recruitment Larch Spruce

Mesh-supported v2O5-WO3/TiO2 nanosheet array catalysts for efficient removal of NOx

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Tungsten 2025年第1期7卷 100-111页

作者： Zhi-Qi Zhang Liu Yang Wen Luo vladimir An Jing Li Bao-Dan Liu School of Materials Science and Engineering Northeastern University Foshan Graduate School of Innovation Northeastern University Kizhner Research Center School of Advanced Manufacturing Technologies Tomsk Polytechnic University

The design and synthesis of vanadium-based denitration catalysts with low-temperature activity pose significant challenges in the field of toxic gas *** this study,we have developed a novel approach to fabricate highly efficient v2O5-WO3/TiO2monolithic mesh catalysts for NOxreduction at low ***,TiO2nanosheets with strong adhesion and large surface area were grown on Ti mesh using plasma electrolytic oxidation technology and hydrothermal ***,super-small traces of WO3and v2O5active nano-species were subsequently deposited on TiO2nanosheets using the deposition-precipitation *** to traditional ceramic-based v2O5-WO3/TiO2catalysts,our v2O5-WO3/TiO2monolithic mesh catalyst exhibits superior mechanical performance,excellent thermal conductivity,lower pressure drop,higher utilization of active components,and stronger synergistic ***,the v2O5-WO3/TiO2monolithic mesh catalysts exhibited excellent low-temperature catalytic activity with 98% of NOxconversion at 220℃,and remarkable long-term SO2tolerance and water resistance in the selective catalytic reduction（SCR） of NOxwith *** SCR reaction of tiny v2O5and WO3active species supported on TiO2nanosheets directly demonstrated to follow the Eley-Rideal mechanism by in situ infrared spectra.

关键词： Low temperature activity Monolithic mesh catalysts NH3-SCR SO2 tolerance v2O5-WO3/TiO2

Elaboration of a conceptual solution for the development of the Arctic shelf from seasonally flooded coastal areas

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International Journal of Mining Science and Technology 2022年第1期32卷 113-119页

作者： vladimir S.Litvinenko Mikhail v.Dvoynikov vladimir L.Trushko Saint-Petersburg Mining University Saint-Petersburg 199106Russia

Currently,construction of facilities in the Arctic is carried out on sand islands,but there are limitations for remote coastal *** restrictions are associated with the lack of quarries with construction sand in the immediate vicinity of the work site,as well as the risk of seasonal flooding of the *** article includes conceptual solutions for construction of modular piling in Arctic nearshore conditions,upon which drilling rigs and auxiliary equipment can be placed for the purpose of subsequent wildcatting,development and exploratory extended reach drilling wells(with measured depth about 15000 m).During the construction of the modular piling foundations,a mathematical simulation of the thermodynamic condition of the frozen ground was conducted,and the bearing capacity of the foundations was *** proposed solutions will solve these problems by constructing modular pile foundations and placing the necessary infrastructure on them,taking into account the distribution of loads during operation in seasonally flooded areas.

关键词： Drilling&drillholes Stress analysis Offshore engineering Infrastructure planning Geotechnical engineering Extended reach drilling

Provenance of Precambrian Fe- and Al-rich Metapelites in the Yenisey Ridge and Kuznetsk Alatau, Siberia: Geochemical Signatures

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Acta Geologica Sinica(English Edition) 2007年第3期81卷 409-423页

作者： Igor I. LIKHANOv vladimir v. REvERDATTO Institute of Geology and Mineralogy Siberian Branch Russian Academy of SciencesPr. Acad. Koptyuga3Novosibirsk630090Russian Federation

Major, trace and rare earth element contents of Fe- and Al-rich metapelites from the Korda （Yenisey Ridge） and Amar （Kuznetsk Alatau） formations were determined to examine the nature, origin and evolution of their protoliths. Results indicate that these rocks are the redeposited and metamorphosed products of Precambrian kaolinitic weathering crusts, while the geochemical distinctions between the studied metapelites are determined by different weathering conditions in the source area and tectonic settings. The protolith of the Korda Formation metapelites was produced by erosion products of the post-Archean granitoid rocks, which accumulated under humid climate conditions in shallow-water basins along the continental margin. The geochemical characteristics of the deeper primary deposits of the Amar Formation suggest that volcanogenic material of mafic composition derived from an island-arc environment had a major role in supplying the erosion zone. These results agree with lithofacies data and with the geodynamic reconstruction of the evolution of the Yenisey Ridge and Kuznetsk Alatau during the Mesoproterozoic and Neoproterozoic, respectively. It was shown that REEs had limited mobility during contact metamorphism. The coherent mobility of REEs during collisional metamorphism may be attributed both to mineral reactions responsible for modal changes and to local chemical heterogeneity inherited from the initial protolith.

关键词： geochemistry protolith pelitic schists Kuznetsk Alatau Yenisey Ridge Russia

Role of the Rossiter-McLaughlin effect in the study of close binaries

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Research in Astronomy and Astrophysics 2019年第3期19卷 21-30页

作者： Galina N.Dryomova vladimir v.Dryomov Russian Federal Nuclear Centre

This paper is devoted to binary stars belonging to the class of eclipsing-variable *** and spectroscopic analysis of eclipses allows us to determine geometric parameters of the orbit and physical characteristics of stellar components as well as inclinations of stellar equators to the orbital plane. Estimations of inclinations can be obtained from measurement of the Rossiter-McLaughlin effect, which is discussed using examples of some eccentric binaries with an anomalous apsidal effect. Our task is to find the complete spectrum of solutions of the equation of apsidal motion, depending on the inclinations of the polar axes of the components to the orbital one for these systems, based on their individual spectroscopic and photometric observational data. The matrix of solutions allows us to select those pairs of polar inclinations that provide agreement with the observational apsidal period.

关键词： Rossiter-McLaughlin effect: eclipsing-variable stars apsidal effect individual binaries: AI Hya,NY Cep,EW Ori,DI Her,AS Cam

Tracing molecular margins of lung cancer by internal extractive electrospray ionization mass spectrometry

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Chinese Chemical Letters 2025年第2期36卷 493-497页

作者： Haiyan Lu Jiayue Ye Yiping Wei Hua Zhang Konstantin Chingin vladimir Frankevich Huanwen Chen State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin University Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation East China University of Technology The Second Affiliated Hospital of Nanchang University School of Pharmacy Jiangxi University of Chinese Medicine National Medical Research Center for Obstetrics Gynecology and Perinatology named after Academician V.I.Kulakov of Ministry of Healthcare of Russian Federation

Accurate determination of lung cancer margins at the molecular level is of great significance to determine the optimal extent of resection during surgical operation and reduce the risk of postoperative *** this study, internal extractive electrospray ionization mass spectrometry(i EESI-MS) was used to trace potential molecular tumor margins in lung cancer tissue. Molecular differential model for the determination of lung cancer tumor margin was established via partial least-squares discriminant analysis (PLS-DA)of iEESI-MS data collected from lung tissue pieces within cancer tumor area and iEESI-MS data collected from lung tissue pieces outside cancer tumor area. Proof-of-concept data demonstrate that the developed molecular differential model yields ca. 1–2 mm wider potential molecular tumor margin of a lung cancer compared to the conventional histological analysis, showing promising potential of iEESI-MS to increase the accuracy of tumor margins determination and lower risk of lung cancer postoperative recurrence. Furthermore, our results revealed that creatine and taurine showed positive correlations with lung cancer.

关键词： Internal extractive electrospray ionization Lung cancer Mouse models Postoperative recurrence Tumor margins

Arrestins:structural disorder creates rich functionality

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Protein & Cell 2018年第12期9卷 986-1003页

作者： vsevolod v.Gurevich Eugenia v.Gurevich vladimir N.Uversky Department of Pharmacology Vanderbilt UniversityNashvilleTN 37232USA Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute Morsani College of Medicine University of South FloridaTampaFL 33612USA Institute for Biological Instrumentation Russian Academy of SciencesPushchinoMoscow RegionRussia 142290

Arrestins are soluble relatively small 44-46 kDa proteins that specifically bind hundreds of active phosphorylated GPCRs and dozens of non-receptor partners. There are binding partners that demonstrate preference for each of the known arrestin conformations: free, receptor-bound, and microtubule-bound. Recent evidence suggests that conformational flexibility in every functional state is the defining characteristic of arrestins. Flexibility, or plasticity, of proteins is often described as structural disorder, in contrast to the fixed conformational order observed in high-resolution crystal structures. However, protein-protein interactions often involve highly flexible elements that can assume many distinct conformations upon binding to different partners. Existing evidence suggests that arrestins are no exception to this rule: their flexibility is necessary for functional versatility. The data on arrestins and many other multi-functional proteins indicate that in many cases, "order" might be artificially imposed by highly non-physiological crystallization conditions and/or crystal packing forces. In contrast, conformational flexibility (and its extreme case, intrinsic disorder) is a more natural state of proteins, representing true biological order that underlies their physiologically relevant functions.

关键词： EPR GPCR NMR arrestin crystal structure disorder protein-protein interactions

Sensing Characteristics of Mixed-Potential-Type YSZ-Based NO_x Sensor Using Au-Doped NiO Sensing Electrode

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稀有金属材料与工程 2006年第A3期35卷 36-39页

作者： vladimir v.Plashnitsa Taro Ueda Norio Miura Art Science and Technology Center for Cooperative ResearchKyushu UniversityKasuga-ShiFukuoka 816-8580Japan Interdisciplinary Graduate School of Engineering Sciences Kyushu UniversityKasuga-shiFukuoka 816-8580Japan

The nano-structured NiO powder obtained by sol-gel method was doped with 10 wt% gold in order to modify its morphology as well as its electrochemical catalytic *** NO_x sensing characteristics of mixed-potential-type YSZ-based planar sensors attached with each of the nano-NiO and the Au-doped nano-NiO materials as a sensing electrode SE) were examined at temperatures of 700℃～800℃.The Au-doped NiO-SE was found to give a large enhancement in the NO_2 sensitivity as well as the NO_2 selectivity at 800℃under wet condition,in comparison with the pure *** reason for the improvement in the NO_2 sensitivity was examined based on the data of polarization curves,impedance spectra and catalytic activity for the gas-phase NO_2 decomposition.

关键词： NO_x sensor mixed potential NiO nanostructure YSZ Au

Advances in small animal mesentery models for in vivo flow cytometry,dynamic microscopy,and drug screening

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World Journal of Gastroenterology 2007年第2期13卷 192-218页

作者： Ekaterina I Galanzha valery v Tuchin vladimir P Zharov Philips Classic Laser Laboratories University of Arkansas for Medical Sciences (UAMS) Little Rock AR United States Department of Optics and Biomedical Physics Research-Educational Institute of Optics and Biophotonics Saratov State University Saratov Russia Department of Optics and Biomedical Physics Research-Educational Institute of Optics and Biophotonics Saratov State University Saratov Russia Philips Classic Laser Laboratories University of Arkansas for Medical Sciences (UAMS) Little Rock AR United States

Using animal mesentery with intravital optical microscopy is a well-established experimental model for studying blood and lymph microcirculation in vivo. Recent advances in cell biology and optical techniques provide the basis for extending this model for new applications, which should generate significantly improved experimental data. This review summarizes the achievements in this specific area, including in vivo label-free blood and lymph photothermal flow cytometry, super-sensitive fluorescence image cytometry, light scattering and speckle flow cytometry, microvessel dynamic microscopy, infrared (IR) angiography, and high-speed imaging of individual cells in fast flow. The capabilities of these techniques, using the rat mesentery model, were demonstrated in various studies; e.g., real-time quantitative detection of circulating and migrating individual blood and cancer cells, studies on vascular dynamics with a focus on lymphatics under normal conditions and under different interventions (e.g. lasers, drugs, nicotine), assessment of lymphatic disturbances from experimental lymphedema, monitoring cell traffic between blood and lymph systems, and high-speed imaging of cell transient deformability in flow. In particular, the obtained results demonstrated that individual cell transportation in living organisms depends on cell type (e.g., normal blood or leukemic cells), the cell’s functional state (e.g., live, apoptotic, or necrotic), and the functional status of the organism. Possible future applications, including in vivo early diagnosis and prevention of disease, monitoring immune response and apoptosis, chemo- and radio-sensitivity tests, and drug screening, are also discussed.

关键词： Lymph microcirculation Transmission digital microscopy Rat mesentery Flow cytometry Photothermal technique