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Tree wave migration across an elevation gradient in the Altai Mountains,Siberia

Journal of Mountain Science 2017年第3期14卷 442-452页

作者： Viacheslav I.kHARUk Sergei T.im Maria L.DVINSkAya kenneth J.RANSON Il'ya A.PETROV Sukachev Institute of Forest SB RAS KrasnoyarskRussia Siberian Federal University KrasnoyarskRussia M.F.Reshetnev Siberian State Aerospace University KrasnoyarskRussia NASA's Goddard Space Flight Center GreenbeltMarylandUSA

The phenomenon of tree waves （hedges and ribbons） formation within the alpine ecotone in Altai Mountains and its response to observed air temperature increase was considered. At the upper limit of tree growth Siberian pine （Pinus sibirica） forms hedges on windward slopes and ribbons on the leeward ones. Hedges were formed by prevailing winds and oriented along winds direction. Ribbons were formed by snow blowing and accumulating on the leeward slope and perpendicular to the prevailing winds, as well as to the elevation gradient. Hedges were always linked with microtopography features, whereas ribbons were not. Trees are migrating upward by waves and new ribbons and hedges are forming at or near tree line, whereas at lower elevations ribbons and hedges are being transformed into dosed forests. Time series of high-resolution satellite scenes （from 1968 to 2OLO） indicated an upslope shift in the position ribbons averaged 155＋26 m （or 3-7 m yr^-1） and crown closure increased （about 35%-90%）. The hedges advance was limited by poor regeneration establishment and was negligible. Regeneration within the ribbon zone was approximately 2.5 times （5060 vs 2120 ha^-1） higher then within the hedges zone. During the last four decades, Siberian pine in both hedges and ribbons strongly increased its growth increment, and recent tree growth rate for 50 year-old trees was about twice higher than those recorded for similarly-aged trees at the beginning of the 20^th century. Hedges and ribbons are phenomena that are widespread within the southern and northern Siberian Mountains.

关键词： Ribbon forest Hedges Siberian forests Alpine treeline Tree waves Siberian pine Altaimountains

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BIOLOGICAL INVASION PROBLEM WITH FREE BOUNDARY NONLOCAL DIFFUSION EQUATION

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数学杂志 2025年第1期45卷 48-56页

作者： HE Yu-rong ZHANG ya-rong School of Science Xi'an University of Architecture and TechnologyXi'an 710055China Xi'an Special Equipment Inspection Institute Xi'an 710065China School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China

In order to better describe the phenomenon of biological invasion,this paper introduces a free boundary model of biological ***,the right free boundary is added to the equation with logistic ***,the existence and uniqueness of local solutions are proved by the Sobolev embedding theorem and the comparison ***,according to the relevant research data and contents of red fire ants,the diffusion area and nest number of red fire ants were simulated without external *** paper mainly simulates the early diffusion process of red fire *** the early diffusion stage,red fire ants grow slowly and then spread over a large area after reaching a certain number.

关键词： Free boundary biological invasion differential equation

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四波混频Autler-Townes分裂中的探测光影响

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原子与分子物理学报 2025年第3期42卷 110-115页

作者：裴丽娅侯海龙北京化工大学数理学院北京100029

在双Λ-型四波混频系统中,研究了探测光强度对Autler-Townes(AT)分裂效应的影响.随着弱探测光强度增大,由缀饰态共振产生的AT分裂双峰间隔不变,但却逐渐增宽线宽且减弱直至消失;而在强耦合光失谐条件下,不对称地位于单光子共振峰两侧的A... 详细信息

在双Λ-型四波混频系统中,研究了探测光强度对Autler-Townes(AT)分裂效应的影响.随着弱探测光强度增大,由缀饰态共振产生的AT分裂双峰间隔不变,但却逐渐增宽线宽且减弱直至消失;而在强耦合光失谐条件下,不对称地位于单光子共振峰两侧的AT分裂双峰却会逐渐趋于对称分布.详细讨论了探测光场对原子的缀饰影响,提出通过探测光强度可以调控原子两基态之间的有效Raman相干,从而影响AT分裂双峰的特征.

关键词：四波混频原子相干 Autler-Townes分裂缀饰态横向弛豫率

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绿原酸对中性粒细胞功能及胞外诱捕网形成的影响及机制

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中国药理学通报 2025年第1期41卷 101-107页

作者：杨运刘娅王翠彭春红贵州中医药大学第二临床医学院贵州贵阳550025 七星关区中医妇幼集团医院贵州毕节551700 毕节市中医医院贵州毕节551700 贵州医科大学临床医学院贵州贵阳550025 贵州省人民医院呼吸与危重医学科贵州贵阳550002 国家卫健委肺脏免疫性疾病重点实验室贵州贵阳550002

目的探究绿原酸(chlorogenic acid,CGA)对中性粒细胞(neutrophil,NEU)功能及中性粒细胞胞外诱捕网(neutrophil extracellular traps,NETs)形成的影响及机制。方法从小鼠骨髓中分离并纯化NEU;将NEU与CGA共培养,通过CCk-8法筛选共培养适合的干预浓度;检测NEU迁移能力、髓过氧化物酶(MPO)以及脱颗粒弹性蛋白酶(NE)、基质金属蛋白酶9(MMP-9)的水平观察CGA对NEU功能的影响;免疫荧光法观察NETs的主要结构组蛋白H3及DNA骨架,以及检测NEU释放的游离DNA(cf-DNA)含量,观察NETs的形成情况;检测NEU产生的活性氧(ROS)水平,以确定CGA是否影响NEU释放NETs过程中的ROS的生成。结果CGA在浓度为100、200、400μmol·L^(-1)时对NEU活性有明显抑制作用(Pk)相比,CGA(100、200、400μmol·L^(-1))干预后,细胞迁移能力及MPO、NE、MMP-9分泌量增加(P<0.05),组蛋白H3及DNA骨架、cf-DNA的释放量明显增加(P<0.01),细胞产生的ROS也明显增加(P<0.01),上述作用在一定范围内具有浓度依赖性。结论CGA能够增强NEU功能及促进NETs的形成,可能与促进细胞内ROS水平增加有关。

关键词：绿原酸中性粒细胞胞外诱捕网免疫抗菌活性氧

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主体结构荷载可控的新型组合式防护结构(Ⅱ)：影响因素及设计理念

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爆炸与冲击 2025年第1期45卷 011101-1-011101-12页

作者：方秦高矗孔祥振杨亚陆军工程大学爆炸冲击防灾减灾国家重点实验室江苏南京210007 内蒙古财经大学财政税务学院内蒙古呼和浩特010070

为明确泡沫混凝土厚度和强度对组合式防护结构抗爆性能的影响，充分发挥和合理利用泡沫混凝土良好的消波特性，首先通过试验及数值模拟探讨不同泡沫混凝土厚度和强度对组合式防护结构抗爆性能的影响，并分析分层梯度泡沫混凝土在爆炸波... 详细信息

为明确泡沫混凝土厚度和强度对组合式防护结构抗爆性能的影响，充分发挥和合理利用泡沫混凝土良好的消波特性，首先通过试验及数值模拟探讨不同泡沫混凝土厚度和强度对组合式防护结构抗爆性能的影响，并分析分层梯度泡沫混凝土在爆炸波作用下的消波特性。然后将组合式防护结构与采用中粗砂为分配层的传统成层式结构进行对比分析验证其优越性，在此基础上，总结凝练出组合式防护结构的主体结构荷载可控的设计理念。结果表明，利用泡沫混凝土材料较长的屈服平台和较低的波阻抗，以泡沫混凝土作为能量调控层，通过设计泡沫混凝土强度等级（密度等级）和厚度以及采用多层梯度泡沫混凝土，可使得作用于主体结构上的爆炸荷载峰值恰为泡沫混凝土屈服强度，实现对主体结构上荷载的可控设计，有效解决了中粗砂为分配层的传统成层式结构不易控制作用于主体结构上荷载的问题。研究结果可为抗新型钻地弹的防护设计提供重要参考。

关键词：泡沫混凝土组合式防护结构可控设计爆炸波消波

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Tree clusters migration into alpine tundra,Siberia

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Journal of Mountain Science 2022年第12期19卷 3426-3440页

作者： kHARUk Viacheslav I. PETROV II'ya A. im Sergei T. GOLYUkOV Alexey S. DVINSkAya Maria L. SHUSHPANOV Alexander S. Sukacheu Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk 660036Russia Siberian Federal University Svobodny str.79Krasnoyarsk 660041Russia Reshetneu Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk 66014Russia Tomsk State University Leninastr.36Tomsk 634050Russia

We hypothesize that in mountain windy habitat trees formed clusters(hedges)as adaptive structures for seedlings’rooting,survival,and tress’upslope *** studied hedges formed by Siberian pine(Pinus sibirica du Tour)and larch(Larix sibirica Ledeb.)within the treeline ecotone in southern Siberian Mountains,investigated hedges formation,evolution,habitat amelioration,and analyzed tree’s growth index(GI)dependence on the eco-climate variables(air temperature,precipitation,soil moisture,wind speed)and relief features(elevation,aspect,slope steepness,and terrain curvature).We conducted a ground survey,measured biometrical parameters of trees and hedges,determined species composition and tree physiognomy,soil types and nutrient contents,and sampled wood cores and applied dendrochronology for trees’GI *** high-resolution satellite scenes for hedge detection and upslope migration,we found that winter winds and soil moisture are the main constraints of trees’settlement and *** formation always links with wind-sheltered microtopography features(boulders,local depressions or felled trees).Once the first tree is established,a positive feedback is aroused that facilitates seedling rooting and in-hedge habitat *** form a streamlined dense“common crown”that mitigates adverse winter wind *** always orient along the prevailing winds,and trees’uphill migration occurs by seedlings establishment within the leeward hedge *** growth facilitates soil formation and *** concentration of nutrients(k,P,N and S)within hedges exceeds the background by 1.5-5.5 *** extension leads to increased snow accumulation that mitigates the influence of desiccation and snow abrasion and mitigates seasonal water *** the extremely harsh windy habitat,inhedge trees present in mat,prostrate or krummholz *** warming,tree stems and even twigs turn *** that GI dependence on the wind speed is insignificant unt

关键词： Treeline Timberline Hedges Tree migration Siberian pine Larch Tree growth Siberian mountain forests Wind stress Moisture stress

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Larch growth across thermal and moisture gradients in the Siberian Mountains

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Journal of Mountain Science 2023年第1期20卷 101-114页

作者： kHARUk Viacheslav I. PETROV Il'ya A. GOLYUkOV Alexey S. DVINSkAya Maria L. im Sergei T. SHUSHPANOV Alexander S. Sukachev Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk660036Russia Siberian Federal University Svobodny str.79Krasnoyarsk660041Russia Reshetnev Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk660014Russia Tomsk State University Lenina str.36Tomsk634050Russia

Climate-driven changes in the thermal and moisture regimes may variously influence different tree species growth and *** hypothesize that drought resistant Siberian larch(Larix sibirica Ledeb.)and precipitation-sensitive Siberian pine(Pinus sibirica Du Tour)responded differently to climate change along the elevational thermal and precipitation *** studied the influence of air temperature,precipitation,soil moisture,and atmospheric drought(indicated by the drought index SPEI)on larch and pine growth along the southward megaslope of the West Sayan *** found that since 2000 climate change resulted in increasing larch and pine radial growth index(GI)(c.1.5–3times)within treeline(2000–2300 m)and timberline(1900–2000 m)ecotones,*** high precipitation *** the forest-steppe ecotone(1100–1200 m)in which *** is the only species,larch GI stagnated or even *** total forested area increased since 2000 up to+50%in the high elevations,whereas in the low elevations(imberline,trees’GI was stimulated by summer ***,temperature increase in early spring reduces GI due to living tissue activation followed by tissue damage by *** forest-steppe,larch radial growth was mostly dependent on soil *** shifted dependence on moisture to the early dates of the growing *** droughts decreased GI within forest-steppe as well as within treeline,whereas the drought influence on both species within highlands was *** forest-steppe seedlings establishment was poor,whereas it was successful within treeline and *** climate change leads to stagnation or even decrease in Larix sibirica growth in the southern lowland *** combination with poor seedlings establishment,reduced growth threatens the transformation of open lowland forests into forest-steppe and steppe ***,in the highlands warming

关键词： Larch Siberian pine Climate influence on tree radial growth Mountain forests Treeline Timberline Foreststeppe Drought stress Moisture stress

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Persian medicine non-pharmacological therapies for headache：phlebotomy and wet cupping

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Journal of Traditional Chinese Medicine 2018年第3期38卷 457-464页

作者： Akramo Sadat Atyabi Fatemeh Nejatbakhsh Hoorie Mohammadi kenari Fatemeh Eghbalian Mohammad Hos-sein Ayati Laila Shirbeigi Department of Traditional Medicine School of Traditional Medicine Tehran University of Medical Sciences Tehran *** Iran Research Institute for Islamicand Complementary Medicine School of Traditional Medicine Iran University of Medical Sciences Tehran*** Iran Department of History of Medicine School of Traditional Medicine Tehran University of Medical Sciences Tehran *** Iran

OBJECTIVE: To describe the common causes of headache as well as the different methods of Phlebotomy(Fasd) and wet Cupping(Hijamat) based on Persian ***: In this study, we searched Google Scholar, Science Direct, Pub Med and Scopus to get any in vitro or clinical evidence of the efficacy and possible mechanisms of phlebotomy or wet cupping on different types of headaches. Also different types of headaches, according to PM, under the title of "Sodaa"; extracted from famous Persian medical text books with key words including "Sodaa","Bayze" and "Shaqiqe".RESULTS: According to PM, diseases(dystemperament) are created by abnormal alteration in temperament. Temperament is a monolithic quality yielded by interaction between opposing qualities of four elements that are coldness, hotness, dryness and wetness. Headaches are caused by dystemperament(sue-Mizaj) in brain or in total body that are divided into simple and corporal. Common forms of the latter type are Vaporal and Migrant headache(Bokhari and Rihi). Each of these headaches is treated either through phlebotomy or wet ***: In Persian Medicine, Fasd and Hijamat are easy and economical methods for treatment of headache with reasonable results. By describing the precise areas and indications of phlebotomy and wet cupping, this study provides the first step for future clinical trials in this field.

关键词： Headache Phlebotomy Cupping thera-py Sodaa Persian Medicine

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土壤冻融过程中的水热参数化方案研究进展

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高原气象 2025年第1期44卷 1-15页

作者：侯雅李伟平左金清中国气象科学研究院灾害天气国家重点实验室北京100081 中国气象局地球系统数值预报中心北京100081 中国气象局气候预测研究重点开放实验室/国家气候中心北京100081

冻土是陆地冰冻圈的重要组成部分,其冻融循环变化能够影响土壤结构、土壤水热传输以及土壤生物化学等过程,并通过陆-气相互作用影响局地甚至全球天气气候。因此,研究土壤冻融过程对冻土区人类生产生活和了解区域外天气气候变化具有重要... 详细信息

冻土是陆地冰冻圈的重要组成部分,其冻融循环变化能够影响土壤结构、土壤水热传输以及土壤生物化学等过程,并通过陆-气相互作用影响局地甚至全球天气气候。因此,研究土壤冻融过程对冻土区人类生产生活和了解区域外天气气候变化具有重要的科学意义。本文回顾了土壤中的砾石、有机质对土壤冻融过程的影响及物理机制,总结了土壤冻融过程中水热参数化的相关研究成果,包括土壤导热率和水力学参数的计算、水热耦合方案以及冻融锋面计算方案等。相对于普通的矿物质土粒而言,砾石具有高导热率和低热容,有机质具有低导热率和高热容,他们对热量在土壤中的传输及土壤温度垂直分布有不同的影响。另外,砾石和有机质的存在改变了土壤孔隙度、土壤基质毛细作用与吸附作用,进而影响水分在土壤中的传输过程和垂直分布。已有研究表明:(1)当前大部分数值模式中土壤导热率采用Johansen方案及其派生方案进行计算,其中Balland-Arp方案考虑了砾石和有机质对土壤导热率的影响,该方案更好地刻画了土壤冻融过程中土壤导热率变化的连续性;综合考虑热-水-变形相互作用的导热率参数化方案可以较好地刻画土壤冻融过程中的水热耦合和土体冻胀的作用,对相变过程中土壤导热率变化特征的模拟更符合实际观测。(2)过冷水参数化方案刻画了土壤液态水在0℃以下存在的事实;相变温度方案描述了土壤相变温度低于0℃且不固定的事实;导水阻抗方案考虑了土壤冻结对土壤水分下渗的阻抗作用,改善了对冻土区水文过程的模拟效果。(3)土壤冻融过程伴随着水分的相变和能量的转化,水热耦合方案的发展能够较好地刻画土壤中热力-水文过程的协同变化特征,细化了对冻融过程中水分和能量相互作用的复杂物理机制的描述。(4)等温框架的数值模式通过模拟每层土壤中间深度的冻融过程代表该模式分层的整体特征,导致对冻融深度的严重高估或低估,尤其是对厚度较大的模式深层土壤,冻融锋面计算方案的提出和应用减小了这种模拟偏差。目前土壤冻融参数化方案的不足之处包括:绝大多数数值模式没有考虑土壤盐分导致土壤水的冰点降低这一事实;虽然大部分数值模式考虑了土壤有机质对土壤水、热传输的影响,但是模式中对土壤有机质含量及垂直分布的考虑与植被根系的生长状态脱节;模式模拟的土壤深度不足并且下边界通量为零的假定不符合实际情况。发展土壤溶质传输参数化方案以模拟盐分的分布、刻画植被根系生长过程和土壤有机质的分布特征、考虑深层土壤对浅层的热力学影响并完善数值模式中的下边界条件,这些是未来陆面模式改进土壤冻融过程模拟的可能方向。

关键词：土壤冻融过程参数化方案土壤导热率土壤水文参数冻融锋水热耦合

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A New <i>Stegolophodon</i>(Proboscidea, Mammalia) from the Irrawaddy Formation of Myanmar

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Open Journal of Geology 2020年第8期10卷 863-873页

作者： Chit sein Department of Geology West Yangon University Yangon Myanmar

The new fossil teeth of Stegolophodon (Proboscidea, Mammalia) were discovered from the terrestrial sediments of the Irrawaddy Formation, in kyauksaungsan and Tebingan areas, Magway Region, central Myanmar. A new Stegolophodon species is established in this paper. Stegolophodon iravaticus shares the characters of the advanced Stegolophodon and the primitive Stegodon. The M3 of S. iravaticus is related to that of the molar of Sand Pit in Tha Chang, Thailand and that of from Dhedari, Pakistan which is included in the Stegolophodon group 6 of Saegusa et al. (2005).

关键词： Stegolophodon iravaticus Irrawaddy Formation Magway Region Myanmar

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