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Vegetation dynamics at the southern edge of the Siberian mountain taiga

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Journal of Mountain Science 2025年第2期22卷 451-465页

作者： IM sergei T KHARUK Viacheslav I PETROV Il'ya A SHUSHPANOV Alexander S DVINSKAYA Maria L ONDAR sergei O V.N.Sukachev Institute of Forest Krasnoyarsk Science Centre of the Siberian Branch of Russian Academy of ScienceKrasnoyarsk 660036Russia Institute of Ecology and Geography Institute of Space and Information TechnologiesSiberian Federal UniversityKrasnoyarsk 660041Russia Laboratory of Biodiversity and Ecology Tomsk State UniversityTomsk 634050Russia Institute of Space Research and High Technologies Reshetnev Siberian State University of Science and TechnologyKrasnoyarsk 660014Russia Department of Biology and Ecology Tuvan State UniversityKyzyl 667000Russia

The growth,survival,and mortality of conifer species in response to the hydrothermal regime have received considerable *** is expected that the highest sensitivity of trees to the warming-drying climate will occur mainly at the edges of the species *** focused on the responses to climate change of the drought-resistant larch(Larix sibirica)and the moisture-sensitive Siberian pine(Pinus sibirica)along the elevation gradient in the Tannu-Ola Ridge,the southern margin where those two species coexist in Siberia by using satellite data(MODIS,Landsat,and microwave),the indexes of gross(GPP)and net(NPP)primary productivity,and tree radial growth index(GI).We found that since the warming restart in the 2000s,the area of larch-dominated forests increased by~150%while the area of pine-dominated forests decreased by~10%.The Siberian pine has retreated at low elevations(<1800 m)and increased its area at higher *** contrast,the area of larch stands increased in both the uphill and downhill ***(Betula spp.)also increased its area at low elevations(about+120%).Since 2001,the forested area increased by~5%.A shrubification,i.e.,an increase in the area of shrubs,was observed at high *** uphill rate of timberline and shrubline migration was about 0.3 m/*** the 2000s,vegetation NPP has increased by 13%.A notable correlation between NPP and the GI of larch and pine was found(r=0.5-0.7).At lower elevations,NPP positively correlated with precipitation and soil moisture,while air temperature and VPD(vapor pressure deficit)increase inhibited *** high elevations,the effects of these variables on productivity *** continuous decline of the Siberian pine forest indicates an inevitable retreat of this species at low elevations and its replacement by larch and birch.

关键词： Trees range changes Mountain taiga Siberian larch Siberian pine Timberline Shrubification Tree uphill migration Forest population dynamics Ecological resilience Habitat suitability

Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

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Neural Regeneration Research 2025年第9期20卷 2454-2463页

作者： Victoria Jiménez Carretero IrisÁlvarez-Merz Jorge Hernández-Campano sergei A.Kirov Jesús M.Hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain Ramón y Cajal Institute for Health Research(IRYCIS) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and Regenerative Medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

连续拉曼光纤激光器光学湍流特征与影响因素探究

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光学学报 2025年

作者：何正樟刘逸文 sergei Turitsyn 舒学文华中科技大学武汉光电国家研究中心 Aston Institute of Photonics Technologies Aston University

激光湍流是一种腔内相干态被破坏而产生的一种非线性演化现象，连续光纤激光器作为一个典型的非线性系统，也成为研究激光湍流现象的良好平台。我们利用耦合非线性薛定谔方程对连续拉曼光纤激光器的湍流现象进行建模，对层流态和湍流态... 详细信息

激光湍流是一种腔内相干态被破坏而产生的一种非线性演化现象，连续光纤激光器作为一个典型的非线性系统，也成为研究激光湍流现象的良好平台。我们利用耦合非线性薛定谔方程对连续拉曼光纤激光器的湍流现象进行建模，对层流态和湍流态的差异性进行表征，分析泵浦功率、腔长、以及光纤布拉格光栅反射镜的带宽对于腔内激光运转状态的影响。仿真实验表明，较大的泵浦功率和较短的腔长都会让腔内非线性效应占据主导地位，降低激光演化的相干性，使得腔内的激光从层流态转变到湍流态。只有一个很窄的光纤布拉格光栅反射带宽区间能让激光系统工作在层流态，因为维持层流态稳定演化对激光模式有严格的要求。这项研究可为更好地开展激光湍流的实验提供理论指导，对于更好地设计连续光纤光纤激光器以及更好地理解非线性物理系统中湍流现象具有重要意义。

关键词：连续拉曼光纤激光器非线性光学光学湍流暗孤子

Using multi-agent simulation to predict natural crossing points for pedestrians and choose locations for mid-block crosswalks

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Geo-Spatial Information Science 2020年第4期23卷 362-374页

作者： Egor Smirnov sergei Dunaenko sergei Kudinov Institute for Design and Urban Studies ITMO UniversitySaint PetersburgRussia

When arranging the pedestrian infrastructure,one of the most important components that make a tangible contribution to the safety of pedestrians is to organize the safe road *** cities,pedestrians often cross a road in the wrong place due to established routes or inadequate location of *** with the participation of pedestrians who crossed the road neglecting the traffic rules,make up a significant part of the total amount of road *** this paper,we propose a method that allows us,on the basis of the results of a computer simulation of pedestrian traffic,to obtain predicted routes for road crossing and to indicate optimal locations for crosswalks that take into account established pedestrian routes and increase their *** work describes an extension for the existing AntRoadPlanner simulation algorithm,which searches for and clusters points where pedestrians cross the roadway and suggests locations for new *** method was tested on the basis of a comparative simulation of several territories before and after its application,as well as on the basis of a field study of the *** developed algorithm can also be used to search for other potentially dangerous places for pedestrians on plans of districts,for example,crossings in places with limited visibility.

关键词： Agent-based modeling computer simulation pedestrian traffic simulation ant road planner pedestrian infrastructure crosswalks pedestrian safety

Conservation utility of botanic garden living collections:Setting a strategy and appropriate methodology

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Plant Diversity 2017年第6期39卷 365-372页

作者： sergei Volis Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of Sciences

In the realities of the modern world, when the natural habitat is rapidly disappearing and the number of imperiled plants is constantly growing, ex situ conservation is gaining importance. To meet this challenge, botanic gardens need to revise both their strategic goals and their methodologies to achieve the new goals. This paper proposes a strategy for the management of threatened plants in living collections,which includes setting regional conservation priorities for the species, creation of genetically representative collections for the high priority species, and usage of these collections in in situ actions. In this strategy, the value of existing and future species living collections for conservation is determined by the species' conservation status and how well the accessions represent their natural genetic variation.

关键词： Biodiversity Threatened plants Ex situ Living collections Conservation strategy Integrated conservation management

Nature and(in-)coherent metamorphic evolution of subducted continental crust in the Neoproterozoic accretionary collage of SW Mongolia

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Geoscience Frontiers 2021年第3期12卷 78-103页

作者： sergei Skuzovatov Vinogradov Institute of Geochemistry SB RAS Favorskogo str.1AIrkutsk 664033Russia

In continental subduction complexes minor volumes of high-pressure mafic rocks(eclogites)often co-exist with much more abundant felsic(granitic)and metasedimentary rocks,which are vital for resolving the origin and metamorphic evolution of subducted continental *** SW Mongolia,the Alag Khadny eclogite-bearing accretionary complex(AKC)is assumed to represent either a remnant of oceanic slab,or a continental margin,subducted in the Early *** we present geochronological,geochemical and petrological evidence of subduction records for the three major types of lithologies that host mafic eclogites,including Mesoproterozoic and Neoproterozoic granitic basement and overlying Neoproterozoic continental-margin *** deformed,ferroan and peraluminous metagranitoids compose a major part of AKC and are interlayered with eclogites in its southern and eastern *** have geochemical features of post-collisional/intraplate high-K calc-alkaline ***-ICP-MS U-Pb zircon geochronology of three distinct metagranite samples show uniform protolith crystallization ages of ca.0.96 Ga and uncertain re-crystallization in the Late Neoproterozoic or Early Paleozoic metamorphic event,whereas abundant zircon inheritance indicates older,Mesoproterozoic to Paleoproterozoic crustal substrate during granite *** existence of Mesoproterozoic crust is highlighted by finding of distinct metagranitoids with the U-Pb zircon crystallization age of ca.1.6 *** isotope signatures(T_(DM)^(C)2.88-1.85 Ga)of zircons from all lithologies preserved the evidence of reworked Neoarchean to Paleoproterozoic crust,similar to that of the Baidrag block(southern Mongolia),for both Mesoproterozoic and Neoproterozoic *** of the specific lithology,the rocks display indicators of high-pressure metamorphic re-equilibration,including garnet(X_(Ca)up to 0.65)+epidote+phengite(Si *** to 3.56)±rutile assemblage in metagranitoids,garnet+phengite(Si ***

关键词： Central Asian Orogenic Belt SW Mongolia Subduction Metasedimentary rocks Orthogneisses Trace elements Zircon U-Pb age Hf isotopes

Spatial analysis of vegetation cover response to climate trends in Khakassia(South Siberia)

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Journal of Mountain Science 2023年第10期20卷 2869-2884页

作者： IM sergei Institute of Natural Sciences and Mathematics Khakassian State University named after N.F.KatanovAbakan 655000Russia V.N.Sukachev Institute of Forest Krasnoyarsk Science Centre of the Siberian Branch of Russian Academy of ScienceKrasnoyarsk 660036Russia Institute of Ecology and Geography Siberian Federal UniversityKrasnoyarsk 660041Russia Institute of Space Research and High Technologies Reshetnev Siberian State University of Science and TechnologyKrasnoyarsk660014Russia

An analysis of the changes in vegetation cover on the territory of the Republic of Khakassia in 2000–2021 due to climatic trends was carried out based on the MODIS *** changes in vegetation cover were estimated based on trends in Normalized Difference Vegetation Index(NDVI)and Enhanced Vegetation Index(EVI).In general,in the 21st century,an increase in the biomass of vegetation cover is *** trends were observed in 16%–22%of the territory,and negative only in 1%–3%.For about 20%of the analyzed territory,a significant influence of climate on the changes in vegetation cover was *** most pronounced negative impact on vegetation cover was caused by summer air and soil temperatures,spring temperature,and summer winds,and the positive impact was caused by summer precipitation and soil *** response of the vegetation cover to climate was non-uniform concerning the ***,a significant correlation with the amount of precipitation was observed for~20%–35%of vegetation growing below 600 m above sea level and for less than 5%above this *** negative effect of summer temperatures on plants prevailed mainly at an elevation below~1400 m above sea *** climate change is likely to lead to significant degradation of vegetation in the steppe and foreststeppe in Khakassia in the coming decades.

关键词： Khakassia South Siberia Vegetation cover Climate trends Remote sensing MODIS NDVI EVI Relief

Complementarities of two existing intermediate conservation approaches

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Plant Diversity 2017年第6期39卷 379-382页

作者： sergei Volis Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences

The need for integration of ex situ and in situ approaches in conservation of plants has long been recognized. However, ex situ collections have numerous limitations that reduce their utility for conservation, necessitating the introduction of new, more appropriate, flexible and less costly *** new approaches that can be called "intermediate" between in situ and ex situ, and bridging them in some way have been proposed over the last two decades. In these approaches material collected in natural populations is planted and maintained outside the original location, but with a different *** the purpose of the inter situs approach is reintroduction, the concern of the quasi in situ approach is long-term storage of species genetic diversity. I view these two approaches as complementary and necessary components of conservation-oriented restoration. In restoration of a degraded habitat using threatened species(i.e. inter situs), quasi in situ collections can serve an important role in providing longterm preservation of these species' genetic diversity and production of seeds needed for restoration.

关键词： Biodiversity Threatened plants In situ Ex situ Quasi in situ Conservation strategy Conservation guidelines

Securing a future for China's plant biodiversity through an integrated conservation approach

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Plant Diversity 2018年第3期40卷 91-105页

作者： sergei Volis Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences

The severely threatened Chinese flora urgently needs a new, well adapted to China and properly formulated conservation strategy. The present review provides a detailed conservation methodology that complements previously described guidelines for preservation of plant species with extremely small populations(PSESP) in China. This review adds to the above concept in several aspects, making it relevant to all threatened Chinese plant species. The proposed integral conservation strategy has the following crucial components:-ecoregional basis for conservation planning and implementation;-a unified scoring system that is used in regional systematic planning for reserve design,monitoring and assessment of efficiency of a reserve network, and creation of seed banks and living collections;-a focus on population demography and the presence of naturally occurring regeneration as the key criteria for defining the conservation status of a species and the appropriate major focus of the species recovery plan;-creation of multi-species living collections that preserve species genetic variation and provide material for in situ actions;-experimental translocation of threatened species into multiple locations within and outside their known *** and implementing these strategies successfully and more fully in China requires that the country changes PA legislation and improves PA management, the National Science Foundation of China(NSFC) re-prioritizes the type of research that receives research funds, and local scientists improve their approach toward information sharing.

关键词： Biodiversity Threatened plants Conservation guidelines Chinese plant conservation Nature reserves Protected areas