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Will the summer sea ice in the Arctic reach a tipping point?

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Atmospheric and Oceanic Science Letters 2023年第3期16卷 58-62页

作者： Ola M.Johannessen elena v.shalina Nansen Scientific Society BergenNorway Nansen International Environmental and Remote Sensing Centre St PetersburgRussia

The Arctic sea-ice cover has decreased in extent,area,and thickness over the last six *** global climate models project that the summer sea-ice extent(SIE)will decline to less than 1 million(mill.)km^(2) in this century,ranging from 2030 to the end of the century,indicating large ***,some models,using the same emission scenarios as required by the Paris Agreement to keep the global temperature below 2°C,indicate that the SIE could be about 2 ***^(2) in 2100 but with a large uncertainty of±1.5 ***^(2).Here,the authors take another approach by exploring the direct relationship between the SIE and atmospheric CO_(2) concentration for the summer-fall *** authors correlate the SIE and In(CO_(2)/CO_(2)r)during the period 1979-2022,where CO_(2)r is the reference value in *** these transient regression equations with an R2 between 0.78 and 0.87,the authors calculate the value that the CO_(2) concentration needs to reach for zero *** results are that,for July,the CO_(2) concentration needs to reach 691±16.5 ppm,for August 604±16.5 ppm,for September 563±17.5 ppm,and for October 620±21 *** values of CO_(2)for an ice-free Arctic are much higher than the targets of the Paris Agreement,which are 450 ppm in 2060 and 425 ppm in 2100,under the IPCC SSP1-2.6 *** these targets can be reached or even almost reached,the "no tipping point"hypothesis for the summer SIE may be valid.

关键词： Sea ice Arctic Climate change Tipping point

Effect of the anionic composition of sulfolane based electrolytes on the performances of lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第8期95卷 231-240,I0005页

作者： elena v.Karaseva elena v.Kuzmina Bo-Quan Li Qiang Zhang vladimir S.Kolosnitsyn Ufa Institute of Chemistry of the Ufa Federal Research Centre of the Russian Academy of Science 71Prospect OktyabryaUfa 450054BashkortostanRussia Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

In lithium-sulfur batteries,cell design,specifically electrolyte design,has a key impact on the battery *** effect of lithium salt anion donor number(DN)(DN[PF_(6)]^(-)=2.5,DN[N(SO_(2)CF_(3))_(2)]^(-)=5.4,DN[ClO_(4)]^(-)=8.4,DN[SO_(3)CF_(3)]^(-)=16.9,and DN[NO_(3)]^(-)=21.1)on the patterns of lithium-sulfur batteries and lithium metal electrode performances with sulfola ne-based electrolytes is *** increase in DN of lithium salt anions leads to an increase in the depth and rate of electrochemical reduction of sulfur and long-chain lithium polysulfides and to a decrease in those for medium-and short-chain lithium *** of lithium salt anions has weak effect on the discharge capacity of lithium-sulfur batteries and the Coulomb efficiency during cycling,with the exception of LiSO_(3)CF_(3)and LiNO_(3).An increase in DN of lithium salt anions leads to an increase in the cycling duration of lithium metal anodes and to a decrease in the presence of lithium *** sulfolane solutions of LiNO_(3)and LiSO_(3)CF_(3),lithium polysulfides do not affect the cycling duration of lithium metal anodes.

关键词： Donor number Lithium salt Sulfolane Lithium polysulfide Electrolyte Lithium-sulfur battery Lithium metal electrode

Thermo-and pH-sensitive Polymer with Pendant Spacer-linked Imidazole Cycles

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Chinese Journal of Polymer Science 2024年第4期42卷 437-445页

作者： Natalya v.Zakharova Stanislav N.Zelinskiy Mariya S.Strelova elena N.Danilovtseva vadim v.Annenkov Institute of Macromolecular Compounds of the Russian Academy of Sciences Saint Petersburg199004Russia Limnological Institute of Siberian Branch of the Russian Academy of Sciences Irkutsk664033Russia

By the reaction of poly(acryloyl chloride) with N-(3-aminopropyl)imidazole, poly(N-(3-(1H-imidazol-1-yl)propyl)acrylamide) was synthesized. The new polymer contains an imidazole ring removed from the main chain by a spacer of five bonds. The structure and purity, molecular weight, hydrodynamic and thermosensitive properties of the obtained sample were studied by1H-and13C-NMR, FTIR spectroscopy, acid-base titration, light scattering, turbidimetry and viscometry. The observed ability of the imidazole-containing polymer to form and destroy associates in water-salt solutions at pH 6.6-7.4 and temperatures of 29-48℃ indicates that these are promising candidates for designing complex biomedical systems. The new polymer is able to form complexes with oligo-DNA more actively than poly(1-vinylimidazole), which is of interest for gene delivery applications. The polymer cross-linked with epichlorohydrin gives micro-relief coatings on the plastic surface, and the modified surface is able to attach negatively charged objects. This thermo-and pH-sensitive polymer modification can be applied to create finely controlled surfaces for cell culturing.

关键词： Imidazole-containing polymer Thermolability pH-sensitivity The modified surface DNA immobilization

Interaction of edge dislocations with voids in tungsten

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Tungsten 2024年第3期6卷 633-646页

作者： Arseny Kazakov Rita I.Babicheva Aleksandr Zinovev Dmitry Terentyev Kun Zhou elena A.Korznikova Sergey v.Dmitriev Research Laboratory for Metals and Alloys under Extreme Impacts Ufa University of Science and Technology Institute for Metals Superplasticity Problems of RAS School of Mechanical and Aerospace Engineering Nanyang Technological University Institute for Nuclear Energy Technology Belgian Nuclear Research Center Technological Machines and Equipment Department Ufa State Petroleum Technological University Institute of Mechanical Science Problems of RAS Institute of Molecule and Crystal Physics UFRC of Russian Academy of Sciences

Tungsten is widely used as a material capable of withstanding extreme operating conditions and is one of the candidates for use in fusion and Generation Ⅳ fission *** modelling implemented to solve various material science problems is an indispensable approach for improving material *** work analyzes the interaction of an edge dislocation with a void in single-crystal tungsten with the help of molecular dynamics *** different approaches for studying the dynamics of dislocations in tungsten that differ in boundary conditions are *** interactions of the dislocation and void at different temperatures are investigated,and based on the obtained stress-strain curves,the dislocation obstacle strength for voids having various diameters is *** is shown that when applied to a crystal with small voids,the model with the fixed boundary conditions returns incorrect ***,the influence of the cell size for the model with periodic boundary conditions is analyzed,and the case of a non-central interaction of a dislocation with a void is *** obtained results improve our understanding of the mechanical response of irradiated materials.

关键词： Tungsten Molecular dynamics method Dislocations voids Boundary conditions

Porous Shish-Kebab Structure Prepared from Oriented UHMWPE Films by Processing in Supercritical CO_(2)

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Chinese Journal of Polymer Science 2024年第1期42卷 97-104,I0009页

作者： Sergey A.Lermontov Aleksey v.Maksimkin Nataliya A.Sipyagina Tarek Dayyoub Alena N.Malkova Evgeniy A.Kolesnikov elena A.Straumal Inna O.Gozhikova Saidkhodzha G.Nematulloev Dmitry v.Telyshev Institute of Physiologically Active Compounds of the Russian Academy of Sciences Chernogolovka 142432Russia Institute for Bionic Technologies and Engineering I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 19991Russia National University of Science and Technology"MISIS"Moscow 119049 Russia Institute of Biomedical Systems National Research University of Electronic TechnologyZelenogradMoscow 124498Russia

For the first time, a highly crystalline porous shish-kebab structure with a high degree of crystallinity was obtained by using a combination of two methods for the formation of porous polymeric materials. A treatment procedure using supercritical carbon dioxide(sc CO_(2))was carried out for oriented ultrahigh molecular weight polyethylene(UHMWPE) films, which provided special conditions for the crystallization of dissolved UHMWPE macromolecules on the surface of oriented UHMWPE crystals. The prepared porous materials were investigated by scanning electron microscopy(SEM) and differential scanning calorimetry(DSC). The particularity of the obtained porous shish-kebab is the absence of the amorphous phase between lamellar crystals(kebabs). The obtained pores had an oval shape, and they were oriented in the orientation direction of the UHMWPE macromolecules. The pore size ranged from 0.05 μm to 4 μm. Controlling the conditions for the crystallization of the UHMWPE macromolecules using supercritical CO_(2) gives the possibility to control the size of both lamellar disks and pores formed.

关键词： UHMWPE Supercritical CO_(2) Porous shish-kebab structure

Wood anatomy chronologies of Scots pine in the foothills of the Western Sayan(Siberia)

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Journal of Forestry Research 2024年第3期35卷 13-27页

作者： elena A.Babushkina Dmitry R.Dergunov Mikhail S.Zharkov Liliana v.Belokopytova Dina F.Zhirnova Bao Yang Jingjing Liu Xiaomei Peng Eugene A.vaganov Khakass Technical Institute Siberian Federal UniversityAbakan 655017Russia Institute of Ecology and Geography Siberian Federal UniversityKrasnoyarsk 660036Russia Mathematical Methods and IT Department Siberian Federal UniversityKrasnoyarsk 660036Russia Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000People's Republic of China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093People's Republic of China Department of Dendroecology V.N.Sukachev Institute of ForestSiberian Branch of the Russian Academy of ScienceKrasnoyarsk 660036Russia

Recent methodological advances in quantitative wood anatomy have provided new insights into the climatic responses of radial growth at the scale of cell structure of tree rings. This study considered long-term chronologies of tracheid measurements, indexed by a novel approach to separate their specific climatic responses from signal recorded in cell production(closely reflected in tree-ring width). To fill gaps in understanding the impact of climate on conifer xylem structure, Scots pine(Pinus sylvestris L.)trees > 200 years old were selected within the forest-steppe zone in southern Siberia. Such habitats undergo mild moisture deficits and the resulting climatic regulation of growth processes. Mean and maximum values of cell radial diameter and cell wall thickness were recorded for each tree *** a low level of climatogenic stress, components of cell chronologies independent of cambial activity were separated to obtain significant climatic signals revealing the timing of the specific stages of tracheid differentiation. Cell expansion lasted from mid-April to July and was impacted similarly to tree-ring width(stimulated by precipitation and stressed by heat), maximum cell size formed late June. A switch in the climatic responses of mean anatomical traits indicated transition to latewood in mid-July. Secondary wall deposition lasted until mid-September, suppressed by end of season temperatures. Generally, anatomical climatic responses were modulated by a less dry May and September compared with summer months.

关键词： Quantitative wood anatomy Cell radial size Cell wall thickness Pinus sylvestris Climatic response

Effects of site preparation methods on soil physical properties and outplanting success of coniferous seedlings in boreal forests

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Journal of Forestry Research 2024年第2期35卷 70-80页

作者： Aleksey S.Ilintsev elena N.Nakvasina Alexander P.Bogdanov Northern Research Institute of Forestry 13 Nikitova Str.Arkhangelsk 163062Russian Federation Department of Silviculture and Forest Management Northern(Arctic)Federal University Named After M.V.LomonosovSevernoy Dviny Emb.17Arkhangelsk 163002Russian Federation

This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of *** study was conducted on 12 forest sites in taiga forests of the European part of Russia.A total of 54 plots were set up to assess seedling survival;root collar diameter,height,and heigh increment were measured for 240 seedlings to assess *** the rooting layer,240 soil samples were taken to determine physical *** study showed that soil treatment methods had no effect on bulk density and total porosity in Cladina ***,reduced soil moisture was noted,particularly in mounds,resulting in increased *** Myrtillus sites,there were increased bulk density,reduced soil moisture,and total porosity in the *** treatment in Polytrichum sites resulted in reduced soil moisture and increased aeration *** the Myrtillus and Polytrichum sites,patch scarification had no effects on physical *** Polytrichum sites,survival rates,heights,and heigh increments of bareroot Norway spruce seedlings in mounds were higher than in patches;however,the same did not apply to *** Cladina and Myrtillus sites,there was no difference in growth for bareroot and containerised seedlings with different soil *** conditions and soil types should be considered when applying different soil treatment methods to ensure high survival rates and successful seedling growth.

关键词： Boreal forests Mechanical site preparation Patch scarification Mounding Soil properties Containerised seedlings Bareroot seedlings

Atherosclerosis originating from childhood:Specific features

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Journal of Biomedical Research 2024年第3期38卷 233-240页

作者： Anastasia v.Poznyak Alexey A.Yakovlev MikhailА.Popov elena B.Zhigmitova vasily N.Sukhorukov Alexander N.Orekhov Institute for Atherosclerosis Research Moscow 121609Russia Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology Moscow 109240Russia Department of Cardiac Surgery Moscow Regional Research and Clinical InstituteMoscow 129110Russia Laboratory of Angiopathology Institute of General Pathology and PathophysiologyMoscow 125315Russia

Atherosclerosis is extremely ***,it is considered a disease of older people,who most often experience problems with the heart and blood *** much attention from the scientific community has been paid to studying the association between aging and atherosclerosis,as well as its consequences,there is evidence that atherosclerosis occurs at an early *** may form both during intrauterine development and in *** plays an important role in childhood atherosclerosis,along with previous infectious diseases and excess weight of both the child and the *** the present review,we examined the development of atherosclerosis and the prerequisites in childhood.

关键词： atherosclerosis childhood pediatrics cardiovascular disease

PD-1^(+)and TIM-3^(+)T cells widely express commonγ-chain cytokine receptors in multiple myeloma patients,and IL-2,IL-7,IL-15 stimulation up-regulates PD-1 and TIM-3 on T cells

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Oncology Research 2024年第10期32卷 1575-1587页

作者： EGOR v.BATOROv ALISA D.INESHINA TATIANA A.ARISTOvA vERA v.DENISOvA SvETLANA A.SIZIKOvA DARIA S.BATOROvA GALINA Y.USHAKOvA EKATERINA Y.SHEvELA elena R.CHERNYKH Laboratory of Cellular Immunotherapy Research Institute of Fundamental and Clinical ImmunologyNovosibirsk630099Russia v.Zelman Institute of Medicine and Psychology Novosibirsk National Research State UniversityNovosibirsk630090Russia Department of Hematology and Bone Marrow Transplantation Research Institute of Fundamental and Clinical ImmunologyNovosibirsk630099Russia

Background:Immune checkpoint ligand-receptor interactions appear to be associated with multiple myeloma(MM)***,previous studies showed the possibility of PD-1 and TIM-3 expression on T cells upon stimulation with commonγ-chain family cytokines in vitro and during homeostatic *** aim of the present work was to study the impact of homeostatic proliferation on the expansion of certain T cell subsets upregulating PD-1 and TIM-3 checkpoint ***:The expression of CD25,CD122,CD127 commonγ-chain cytokine receptors,phosphorylated signal transducer and activator of transcription-5(pSTAT5)and eomesodermin(EOMES)was comparatively assessed with flow cytometry in PD-1-and TIM-3-negative and positive T cells before the conditioning and during the first post-transplant month in peripheral blood samples of MM ***:Substantial proportions of PD-1-and TIM-3-positive T lymphocytes expressed commonγ-chain cytokine receptors and *** of cytokine receptor expressing cells were significantly higher within TIM-3+T cells compared to PD-1+TIM-3−*** proportions of both PD-1-/TIM-3-negative and positive CD8+T cells express EOMES,while only moderate frequencies of CD4+PD-1+/TIM-3+T cells up-regulate this transcription ***,the surface presence of CD25 and intranuclear expression of EOMES in CD4+T cells were mutually exclusive regardless of PD-1 and TIM-3 *** stimulation with commonγ-chain cytokines up-regulates PD-1 and TIM-3 during the proliferation of initially PD-1/TIM-3-negative T cells but fails to expand initially PD-1+and TIM-3+T cell subsets in ***:Both PD-1 and TIM-3 expressing T cells appear to be able to respond to homeostatic cytokine *** in commonγ-chain cytokine receptor expression between PD-1+and TIM-3+T cells may reflect functional dissimilarity of these cell *** blockade appears to alleviate lymphopenia-induced prolif

关键词： Autologous hematopoietic stem cell transplantation(AHSCT) CD25 CD122 Eomesodermin(EOMES) Homeostatic proliferation