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Impact of historical pattern of human activities and natural environment on wetland in heilongjiang River Basin

Frontiers of Environmental science & Engineering 2023年第12期17卷 123-136页

作者： Chaoxue song Hong s.he Kai Liu Haibo Du Justin Krohn Key Laboratory of Geographical Processes and Ecological security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun 130024China school of Natural Resources University of MissouriColumbiaMO 65211USA Center for Applied Research and Engagement systems University of MissouriColumbiaMO 65211USA

Mid and high latitude wetlands are becoming fragmented and losing ecosystem functions at a much faster rate than many other *** is due in part to increasing human activities and climate *** this study,we analyzed wetland distribution and spatial pattern changes for the heilongjiang River Basin over the past 100 *** identified the driving factors and quantified the relative importance of each factor based on landscape pattern metrics and machine learning *** results show that wetlands have been fragmented into smaller and regular patches with dominant factors that varied at different *** features play the most important role in patterns of wetland change for the entire basin(with 50%-60%of relative importance).Human activities are more important than climate change at the century scale,but less important when magnified at the decadal *** the early 1900s,human activities were relatively low and localized and remained that way in the subsequent ***,the effect of human activities on wetland area of the entire basin is weaker when examined at the magnified decadal *** results also show that human activities are more important on the Chinese side of the heilongjiang River Basin,in the ZeyaBureya Plain on the Russian side,and at lower altitudes(0-100 m).Revealing the spatial and temporal processes and driving factors over the past 100 yr helps researchers and policymakers understand and anticipate wetland change and design effective conservation and restoration policies.

关键词： Wetland change Human activities Climate change Driving mechanism heilongjiang River Basin

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On governance in the long-term vegetation process: How to discover the rules?

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Frontiers in Biology 2009年第4期4卷 557-568页

作者： Laszlo ORLOCI Kate s.he Departamento de Ecologia Universidade Federal do Rio Grande do SulPorto AlegreRS91540-000Brazil Department of Biological sciences Murray State UniversityMurrayKY 42071USA

Ecological practice is telling us that to identify Nature’s rules,we should look for regularities in the resulting *** rules are involved and the effects are manifested by compositional,functional,and structural *** paper’s focus is on two conjectures regarding the governance of specific transition compo-nents,the first supposedly under global co-ordination,and the second under superimposed site specific instability *** reality of any apparent regularity in these is the sole condition for the regularity’s acceptance as a *** is testable but in retrospect only,based on time series *** long pollen spectra supply the evidence,the time period involved is measured in thousands of *** maximal usefulness,a spectrum should have a long period length,dated horizons intensely sampled at short time steps,and precisely identified *** length and time step width matter because both may have a masking effect on the *** is,of course,a natural limit for period length,which is set by the age of the pollen bearing *** completed the analysis of 23 spectra using techniques deemed suitable for testing the *** spectra originated from sites in the Americas where we found suitable spectra in sufficient numbers and in geographic contiguity from the Arctic region to the *** presented results have clear indications that the two conjectures identify real *** main body of the paper narrates the analyses and provides *** materials,too voluminous for inclusion in the paper,are made available on the Internet at URL:*** linking to“Appen-dices Ta”.

关键词： governance long-term process vegetation rules

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Response of larch species to climate changes

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Journal of Plant Ecology 2008年第3期1卷 203-205页

作者： Wenfang Leng Hong s.he Hongjuan Liu Group of Landscape Ecology Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China The Tourism Department Qinghuangdao Institute of TechnologyQinghuangdao 066100China Department of Forest School of Nature ResourcesUniversity of MissouriColumbiaMO 65211USA Group of Information Management of Agriculture and Ecosystem Center for Agriculture Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China

Global warming has changed the distributions of forests of northeastern *** are very important species in this *** the potential distributions of Larix species and their responses to climate change would attract more and more *** paper predicted the potential distributions of three Larix species based on‘climatic-topographic’relationships by logistic *** results showed that *** is predicted to retreat northwestward by 220 km by 2050 and by 270 km more by 2100;*** *** is predicted to retreat northwestward by 200 km by 2050 and by 190 to 300 km more by 2100;***-rupprechtii is predicted to retreat northeastward by 200 km by 2050 and by 250 to 400 km more by *** indicated that *** could have its optimum latitude moved into Russia,*** *** could move to the small Xing’an Mountains and *** would move to the middle part of the Great Xing’an Mountains.

关键词： Larix gmelinii Larix olgensis var.changpaiensis Larix principis-rupprechtii logistic regression climate change Northeastern China

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Carbon allocation in Picea jezoensis:Adaptation strategies of a non-treeline species at its upper elevation limit

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Forest Ecosystems 2024年第3期11卷 347-357页

作者： Renkai Dong Na Li Mai-he Li Yu Cong Haibo Du Decai Gao Hong s.he Key Laboratory of Geographical Processes and Ecological security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun130024China school of Natural Resources University of MissouriColumbiaMO65211USA swiss Federal Institute for Forest Snow and Landscape Research WSL8903BirmensdorfSwitzerland Northeast Institute of Geography and Agricultural Ecology Chinese Academy of SciencesChangchun130102China school of Life science Hebei UniversityBaoding071002China

Understanding the physiological adaptations of non-treeline trees to environmental stress is important to understand future shifts in species composition and distribution of current treeline *** aim of the present study was to elucidate the mechanisms of the formation of the upper elevation limit of non-treeline tree species,Picea jezoensis,and the carbon allocation strategies of the species on Changbai *** employed the^(13)C in situ pulse labeling technique to trace the distribution of photosynthetically assimilated carbon in Picea jezoensis at different elevational positions(tree species at its upper elevation limit(TsAUE,1,700 m a.s.l.)under treeline ecotone;tree species at a lower elevation position(TsALE,1,400 m a.s.l.).We analyzed^(13)C and the non-structural carbohydrate(NsC)concentrations in various tissues following *** findings revealed a significant shift in carbon allocation in TsAUE compared to *** was a pronounced increase inδ^(13)C allocation to belowground components(roots,soil,soil respiration)in TsAUE compared to ***,the C flow rate within the plant-soil-atmos.here system was faster,and the C residence time in the plant was shorter in *** trends indicate enhanced C sink activity in belowground tissues in TsAUE,with newly assimilated C being preferentially directed there,suggesting a more conservative C allocation strategy by *** at higher elevations under harsher *** a strategy,prioritizing C storage in roots,likely aids in withstanding winter cold stress at the expense of aboveground growth during the growing season,leading to reduced growth of TsAUE compared to *** results of the present study shed light on the adaptive mechanisms governing the upper elevation limits of non-treeline trees,and enhances our understanding of how non-treeline species might respond to ongoing climate change.

关键词： ^(13)C pulse labeling Carbon distribution Non-structural carbohydrates(NsC) Non-treeline species sink activity stressful environments Upper elevation limit

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The interaction between temperature and precipitation on the potential distribution range of Betula ermanii in the alpine treeline ecotone on the Changbai Mountain

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Forest Ecosystems 2024年第1期11卷 42-51页

作者： Yu Cong Yongfeng Gu Wen J.Wang Lei Wang Zhenshan Xue Yingyi Chen Yinghua Jin Jiawei Xu Mai-he Li Hong s.he Ming Jiang Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China Key Laboratory of Geographical Processes and Ecological security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun 130024China school of Natural Resources University of MissouriColumbiaMO 65211USA swiss Federal Institute for Forest Snow and Landscape Research WSLCH-8903 BirmensdorfSwitzerland school of Life science Hebei UniversityBaoding 071000China

Alpine treeline ecotones are highly sensitive to climate *** low temperature-determined alpine treeline is expected to shift upwards in response to global ***,little is known about how temperature interacts with other important factors to influence the distribution range of tree species within and beyond the alpine treeline ***,we used a GF-2 satellite image,along with bioclimatic and topographic variables,to develop an ensemble suitable habitat model based on the species distribution modeling algorithms in *** investigated the distribution of suitable habitats for *** under three climate change scenarios(i.e.,low(ssP126),moderate(ssP370)and extreme(ssP585)future emission trajectories)between two consecutive time periods(i.e.,current-2055,and 2055-2085).By 2055,the potential distribution range of *** will expand under all three climate *** medium and high suitable areas will decline under ssP370 and ssP585scenarios from 2055 to ***,under the three climate scenarios,the uppermost altitudes of low suitable habitat will rise to 2,329 m a.s.l.,while the altitudes of medium and high suitable habitats will fall to 2,201 and2,051 m *** 2085,*** promotes the expansion of *** distribution range in Changbai Mountain,and this expansion will be modified by precipitation as climate warming *** interaction between temperature and precipitation plays a significant role in shaping the potential distribution range of *** in the alpine treeline *** study reveals the link between environmental factors,habitat distribution,and species distribution in the alpine treeline ecotone,providing valuable insights into the impacts of climate change on high-elevation vegetation,and contributing to mountain biodiversity conservation and sustainable development.

关键词： Biomod2 Birch Climate change Climate scenarios Habitat suitability Range shift Treeline species

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soluble EphB4-A New Inhibitor For Choroidal Neovascularization

Soluble EphB4-A New Inhibitor For Choroidal Neovascularizati...

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第三届全球华人眼科学术大会暨中华医学会第十一届全国眼科学术大会

作者： s.he R．subramanyan V．Krasnoperov Y．Kim D．Zhu E．A．Barron A．Rodriguez s．J．Ryan P．s．Gill D．R．Hinton Departments of Pathology Ophthalmology and MedicineKeck School of Medicine at University of Southern California the Doheny Eye Institute Los AngelesCA and Vasgene TherapeuticsInc Los Angeles CA

Purpose: EphB4 receptor and its ligand (EphrinB2) are critical regulators of cell adhesion, growth, migration and vascular assembly. Recombinant soluble form of EphB4 extracellular domain (sEphB4) inhibits vessel maturation and angiogenesis. The purpose of this study was to evaluate the effect sEphB4 receptor on the regulation of choroidal endothelial cell (CEC) and retinal pigment epithelial cell function (RPE) cell function and the inhibition of laser induced choroidal neovascularization (CNV). Methods: Early passage bovine CEC and human fetal RPE cells were used in the study. Effect of sEphB4 on PDGF or VEGF induced CEC

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基于Kappa系数的景观变化测度——以辽宁省中部城市群为例

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生态学报 2005年第4期25卷 778-784,i001页

作者：布仁仓常禹胡远满李秀珍贺红士中国科学院沈阳应用生态研究所

分析了辽宁省中部城市群1988～1998年间的景观变化,结果表明沼泽地从景观中完全消失,沙地的变化弹性最大,耕地的变化最小。优势景观类型(耕地)的转化方向较多,非优势景观类型(沙地)转化的方向少。某些景观类型之间较稳定地相互转化(林... 详细信息

分析了辽宁省中部城市群1988～1998年间的景观变化,结果表明沼泽地从景观中完全消失,沙地的变化弹性最大,耕地的变化最小。优势景观类型(耕地)的转化方向较多,非优势景观类型(沙地)转化的方向少。某些景观类型之间较稳定地相互转化(林地和耕地) ,但某些景观类型之间转化极不稳定(耕地和沼泽地)。总体上,景观的变化趋势是:居住用地面积增加,占居了周围的耕地,促进了耕地向菜地的转化。面积大的景观类型变化小(林地和耕地) ,相反,面积小的类型变化大。Kappa系数分析结果表明,位置、数量、随机和标准Kappa系数都降低,即景观在数量上丢失3.86 %的信息,位置上丢失5 .95 %的信息,丢失的综合信息为6 .89%。而且建议进行综合信息评价时用随机Kappa系数,因为它既不考虑数量,又不考虑位置的影响。虽然Kappa系数从位置、数量和综合信息方面揭示了景观变化,但是这些分析是单方面的,而且没有说明在整个图的一致率中由于空间位置、数量和偶然因子所引起的一致率和变化率。景观变化过程中,不考虑空间位置和数量的情况下,景观在空间上随机分布,某个象元属于某个类型的概率等于1/ J(J=类型总数) (8% )。随景观中类型数量的减少,偶然一致率所占的比重增加,因此建议对单个类型不要进行一致性分析。

关键词：转移矩阵一致性分析景观动态 Kappa系数

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The effects of enriched environment from birth on dendritic complexity and synaptic plasticity in CA1 pyramidal neuron

The effects of enriched environment from birth on dendritic ...

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中国神经科学学会第四次会员代表大会暨第七届全国学术会议

作者： s.he~(1,2),N.LIU~(1,2),L.LIU~(1,2),J.J.CAI~1,X.YU~1 1 Institute of Neuroscience and Key Laboratory of Neurobiology,shanghai Institute of Biological sciences,Chinese Academy of sciences,shanghai,China 2 Graduate school of the Chinese Academy of sciences,shanghai 200031,China

＜正＞Enriched Environment（EE） is a well-established paradigm for naturally increasing neural activity in *** have shown that rearing adult rodents in enriched environments elicit changes throughout the brain,including the levels of various proteins,the extent of dendritic arborization and synapse strength of various neural ***, rodents reared in EE have improved spatial learning compared to control animals reared in standard ***, most of the above mentioned research were performed using adult *** different mechanisms of synaptic plasticity exist between early development and the adult stage,and the neural consequences of environmental enrichment in young animals is still largely unknown,we established an EE paradigm from *** conveniently mark hippocampus CA1 pyramidal neuron,we used a Thy-1 promoter driven GFP *** the mouse pups in EE for 2 week was sufficient to considerably increase both the total dendritic branch length and tip number in pyramidal neurons compared to animals reared in standard *** addition,we performed whole-cell patch clamp recordings in CA1 pyramidal neurons from acute brain slices of EE and standard housed *** find that NMDAR-dependent LTP is facilitated at the CAl-schaffer collateral synapse,and the strength of LTD is also *** electrophysiological tests are ongoing.

关键词： enriched environment dendrite arborization synaptic plasticity

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Constraints on holographic QCD phase transitions from PTA observations

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： song he Li Li sai Wang shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University school of Physical science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAs Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences school of Fundamental Physics and Mathematical sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) school of Physical sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

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Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic heterointerfaces for superior Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 191-204页

作者： Zizhuang he Lingzi shi Ran sun Lianfei Ding Mukun he Jiaming Li Hua Guo Tiande Gao Panbo Liu school of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710129People’s Republic of China school of Marine science and Technology Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China

Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase ***,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation *** results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial ***,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic ***,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon *** design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption.

关键词： Magnetic heterointerfaces Phase evolution Interfacial polarization Magnetic coupling Electromagnetic wave absorption

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