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An unprotected vulnerable relict subtropical conifer-Keteleeria evelyniana: Its forests, populations, growth and endangerment by invasive alien plant species in China

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Plant Diversity 2024年第5期46卷 648-660页

作者： Cindy Q.Tang Min-Rui Du Huan-Chong Wang You-Cai Shi Jia-Le Zeng Shu-Li Xiao peng-Bin Han Jian-Ran Wen Shi-Qian Yao ming-chun peng Chong-Yun Wang Yong-Ping Li Jordi López-Pujol Institute of Ecology and Geobotany College of Ecology and Environmental ScienceYunnan UniversityBuilding#3Guozhong DalouDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina College of Life Sciences Yunnan UniversityShengming Kexueyuan Building#2Chenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina College of Natural Resources Yunnan UniversityChenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina Botanic Institute of Barcelona(IBB CSIC-CMCNC)Passeig del Migdia s/nBarcelona 08038CataloniaSpain Escuela de Ciencias Ambientales Universidad Espíritu Santo(UEES)Samborondon 091650Ecuador

Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien *** the crucial importance of understanding forest dynamics,knowledge gaps persist,particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria *** this study,we investigated the impact of invasive plants on the regeneration of forests dominated by ***,a subtropical relict species in southwestern *** this purpose,we characterized forest dynamics of 160 forest plots featuring *** as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of *** identified four distinct forest types in which *** was *** found that radial growth of *** trees is faster in younger ageclasses today than it was for older trees at the same *** population structure of *** in each forest type exhibited a multimodal age-class ***,three forest types lacked established saplings younger than 10 years old,a situation attributed to the dense coverage of the invasive alien Ageratina *** invasive species resulted in a reduction of understory species ***,our analysis uncovered a significant negative correlation in phylogenetic relatedness(net relatedness index)between native and invasive alien plant species in eastern *** suggests closely related invasive species face heightened competition,hindering successful *** together,our findings indicate that successful establishment and habitat restoration of *** seedling/saplings require effective measures to control invasive plants.

关键词： Keteleeria evelyniana Age structure Regeneration Species diversity Invasive alien species Phylogenetic relatedness

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Forest characteristics,population structure and growth trends of threatened relict Pseudotsuga forrestii in China

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Plant Diversity 2023年第4期45卷 422-433页

作者： Cindy Q.Tang Shi-Qian Yao peng-Bin Han Jian-Ran Wen Shuaifeng Li ming-chun peng Chong-Yun Wang Tetsuya Matsui Yong-Ping Li Shan Lu Yuan He Institute of Ecology and Geobotany College of Ecology and Environmental ScienceYunnan UniversityBuilding ShixunChenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunmingYunnan 650504China College of Life Sciences Yunnan UniversityShengming Kexueyuan Building#2Chenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunmingYunnan 650504China Institute of Highland Forest Science Chinese Academy of ForestryKunmingYunnan 650224China Forestry and Forest Products Research Institute Forest Research and Management OrganizationMatsunosato 1Tsukuba-shiIbaraki-ken305-8687Japan Faculty of Life&Environmental Sciences University of Tsukuba1-1-1 TennodaiTsukubaIbaraki305-8572Japan College of Natural Resources Yunnan UniversityChenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunmingYunnan 650504China Forestry and Grassland Bureau of Diqing Tibetan Autonomous Prefecture 1st Floor of Government BuildingShengping TownDeqing CountyYunnan 674500China Forestry and Grassland Bureau of Weixi Lisu Autonomous County Nanjian Dao#7Baohe TownWeixi Lisu Autonomous CountyYunnan 674600China

Pseudotsuga forrestii is a relict evergreen coniferous tree species in Pinaceae endemic to *** tree numbers have greatly decreased due to deforestation,over-utilization and habitat *** we clarify *** community types,structure,species diversity,seedling recruitments and growth *** identified four *** community types:(1)Pseudotsuga forrestii-Quercus guyavifolia-Acer davidii evergreen coniferous and broad-leaved mixed forest;(2)Pseudotsuga forrestii-Pinus yunnanensis-Quercus guyavifolia evergreen coniferous and broad-leaved mixed forest;(3)Pseudotsuga forrestii evergreen coniferous forest;(4)Pseudotsuga forrestii-Abies georgei *** evergreen coniferous *** forests are characterized by both warm temperate and temperate *** diversity,Pielou evenness,Shannon-Wiener diversity indices ranged from 0.75 to 0.76,0.74-0.81,and 1.62-1.93,respectively,with no significant differences among the four forest *** forest stratification was *** canopy layer was generally 10-25 m tall,with the emergent layer reached 25-42 *** and age structures of *** showed multimodal *** maximum age *** was 570 years with a DBH of 143 *** growth of annual ring width of *** was slow,and generally decreased with age,whereas the basal area at the breast height increased with *** seedlings/saplings were mainly found in unstable *** of *** depends on moderate natural ***,we provide recommendations for *** conservation.

关键词： Pseudotsuga forrestii Community structure Species diversity Population structure Regeneration Growth trend

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Reactive oxygen species:Multidimensional regulators of plant adaptation to abiotic stress and development

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Journal of Integrative Plant Biology 2024年第3期66卷 330-367页

作者： pengtao Wang Wen-Cheng Liu Chao Han Situ Wang ming-Yi Bai chun-peng Song State Key Laboratory of Crop Stress Adaptation and Improvement School of Life SciencesHenan UniversityKaifeng 475004China The Key Laboratory of Plant Development and Environmental Adaptation Biology Ministry of EducationSchool of Life SciencesShandong UniversityQingdao 266237China Faculty of Science McGill UniversityMontreal H3B1X8Canada

Reactive oxygen species(ROS)are produced as undesirable by-products of metabolism in various cellular compartments,especially in response to unfavorable environmental conditions,throughout the life cycle of *** ROS production disrupts normal cellular function and leads to oxidative *** cope with excessive ROS,plants are equipped with a sophisticated antioxidative defense system consisting of enzymatic and non-enzymatic components that scavenge ROS or inhibit their harmful effects on ***,when maintained at relatively low levels,ROS act as signaling molecules that regulate plant growth,development,and adaptation to adverse ***,we provide an overview of current approaches for detecting *** also discuss recent advances in understanding ROS signaling,ROS metabolism,and the roles of ROS in plant growth and responses to various abiotic stresses.

关键词： abiotic stress growth and development plant reactive oxygen species

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Optimal Timing of Business Conversion for Solvency Improvement

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 744-757页

作者： peng LI ming ZHOU School of Finance Nanjing University of Finance and EconomicsNanjing 210023China Center for Applied Statistics and School of Statistics Renmin University of ChinaBeijing 100872China

In this paper,we study the optimal timing to convert the risk of business for an insurance company in order to improve its *** cash flow of company evolves according to a jump-diffusion *** conversion option offers the company an opportunity to transfer the jump risk business *** exchange for this option,the company needs to pay both fixed and proportional transaction *** proportional cost can also be seen as the profit loading of the jump risk *** formulated this problem as an optimal stopping *** solving this stopping problem,we find that the optimal timing of business conversion mainly depends on the profit loading of the jump risk business.A larger profit loading would make the conversion option *** fixed cost,however,only delays the optimal timing of business *** the end,numerical results are provided to illustrate the impacts of transaction costs and environmental parameters to the optimal strategies.

关键词： optimal stopping jump-diffusion process conversion option

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Species richness, forest types and regeneration of Schima in the subtropical forest ecosystem of Yunnan, southwestern China

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Forest Ecosystems 2020年第3期7卷 443-461页

作者： Cindy QTang peng-Bin Han Shuaifeng Li Li-Qin Shen Diao-Shun Huang Yun-Fang Li ming-chun peng Chong-Yun Wang Xiao-Shuang Li Wei Li Wei Wang Zhi-Ying Zhang Institute of Ecology and Geobotany College of Ecology and Environmental ScienceYunnan UniversityKunming650504China Research Institute on Resource Insects Chinese Academy of ForestryKunming650224China Caojian Forest Farm of Yunlong Forestry Bureau Yunlong County672711YunnanChina Yunnan Academy of Forestry Kunming650201China Tibet Agriculture and Animal Husbandry College Linzhi860000China

Background: Schima genus of Theaceae is confined to subtropics and tropics of South, East and Southeast *** species of Schima are distributed in subtropical China. Many of them appear as dominant canopy species in the subtropical forests. To date, Schima species richness distribution patterns of China have remained ***, there has been a longtime debate as to whether forests dominated by Schima species are early or late successional forests. We aim to clarify Schima species richness patterns and these species' roles in the forest succession and regeneration dynamics of the subtropical ecosystem in Yunnan Province, ***: We mapped Schima species richness distribution patterns in China. Based on 71 vegetation plots, we analyzed forest characteristics, population structure, and regeneration dynamics of Schima species in ***: Yunnan was found to harbor the greatest richness and the highest rarity-weighted richness of Schima species in the subtropical regions of China. We classified five primary and six secondary forest types containing Schima species as one of dominants. Yunnan had the high floristic diversity and varying stand structure of forests containing Schima species. The Schima species studied generally had a sporadic regeneration type and a long lifespan. Four species(Schima argentea, Schima villosa, Schima sinensis, Schima sericans) were shade-intolerant. But three species(Schima noronhae, Schima khasiana and Schima wallichii) were considered as bi-modal type species having shade-intolerant and shade-tolerant traits. Schima noronhae was seen to be a top dominant in late successional forests, while S. wallichii was found as a top-dominant in early or middle or late successional forests. ***, Schima villosa, Schima sinensis usually appeared as a top dominant in early or middle successional secondary forests, though they also presented as a second dominant in late-successional forests. Schima argentea and Schima se

关键词： Forest structure Regeneration dynamics Schima Species richness Forest succession Yunnan

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Supercoiled DNA Minicircles under Double-strand Breaks

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Chinese Journal of Polymer Science 2024年第9期42卷 1353-1359,I0007页

作者： Ye-peng Qiao chun-Lai Ren National Laboratory of Solid State Microstructures and Department of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China

Understanding how supercoiled DNA releases intramolecular stress is essential for its functional ***,the molecular mechanism underlying the relaxation process remains insufficiently *** we employed MD simulations based on the oxDNA2 model to investigate the relaxation process of a 336-base pair supercoiled minicircular DNA under double-strand breaks with two fixed *** simulations show that the conformational changes in the DNA occur continuously,with intramolecular stress release happening abruptly only when the DNA chain traverses the breakage *** relaxation process is influenced not only by the separation distance between the fixed ends but also their ***,we observe an inhibitory effect on the relaxation characterized by small angles,where short terminal loops impede DNA conformational adjustments,preserving the supercoiled *** findings elucidate the intricate interplay between DNA conformational change,DNA motion and intramolecular stress release,shedding light on the mechanisms governing the relaxation of supercoiled DNA at the molecular level.

关键词： Supercoiled DNA DNA minicircle DNA relaxation oxDNA model MD simulation

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In-situ powder mixing for laser-based directed energy deposition of functionally graded materials

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Advances in Manufacturing 2024年第1期12卷 150-166页

作者： Ji-peng Chen Shou-chun Xie He Huang School of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing210037People’s Republic of China Nanjing Huirui Photoelectric Technology Co. LtdNanjing211121People’s Republic of China

The mixing of powders is a highly relevant field under additive manufacturing,however,it has attracted limited interest to *** in-situ mixing of various powders remains a significant *** paper proposes a new method utilizing a static mixer for the in-situ mixing of multiple powders through the laser-based directed energy deposition(DED)of functionally graded ***,a powder-mixing experimental platform was established;WC and 316L powders were selected for the mixing ***,scanning electron microscopy,energy dispersive spectroscopy,and image processing were used to visually evaluate the homogeneity and proportion of the in-situ mixed ***,powder-mixing simulations were conducted to determine the powder-mixing *** the simulations,a powder carrier gas flow field and particle mixing were ***,a WC/316L metal matrix composite sample was produced using laser-based DED to verify the application potential of the static *** was found that the static mixer could adjust the powder ratio online,and a response time of 1–2 s should be considered when adjusting the ratio of the mixed powder.A feasible approach for in-situ powder mixing for laser-based DED was demonstrated and investigated,creating the basis for functionally graded materials.

关键词： Laser Deposition Static mixer Powder mixing Functionally graded materials

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Emerging materials and transistors for integrated circuits

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National Science Review 2024年第3期11卷 7-8页

作者： ming Liu Lian-Mao peng Lab of Nanofabrication and Novel Device Integration Institute of Microelectronics Chinese Academy of Sciences Key Laboratory for the Physics and Chemistry of Nanodevices and Center for Carbon-based Electronics School of Electronics Peking University

The device technology for integrated circuits(ICs) has received a great deal of attention in the past decade since the mainstream silicon-based complementary metal-oxide-semiconductor(CMOS) field-effect transistor(FET) for modern ICs had been encountering development bottlenecks due to the combination of power constraints, physics, cost and fabrication processes.

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How the enhanced East Asian summer monsoon regulates total gross primary production in eastern China

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Advances in Climate Change Research 2024年第2期15卷 244-252页

作者： ming-Yu HAN Yong ZHANG Jing peng China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China China Meteorological Administration Institute for Development and Programme Design Beijing 100081China CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences(CAS)Beijing 100029China

Recognizing the relationship between gross primary production(GPP)and precipitation in eastern China,the East Asian Summer Monsoon(EASM)plays a crucial role in shaping *** confirmation of the strong link between EASM and GPP,there remains a notable research gap in understanding the specific impact of the EASM on GPP in different regions of eastern *** we used simulations from Trends in Net Land-Atmosphere Carbon Exchanges(TRENDY)models from 1951 to 2010 and divided eastern China into five subregions for the *** also used the New East Asian Summer Monsoon Index(NEWI)as a quantitative metric to distinguish between periods of strong and weak *** on this,this study aims to investigate the response of GPP in different subregions of eastern ***,under strengthened EASM years(1954,1957,1965,1969,1977,1980,1983,1987,1993 and 1998),East China experienced the most pronounced increase in GPP at 12±21(mean±1 sigma)gC m^(-2) mon^(-1) compared to the weak EASM years(1958,1961,1972,1973,1978,1981,1985,1994,1997 and 2004).In contrast,Southwest China showed a decline in GPP at-4±10 gC m^(-2) mon^(-1).Moreover,GPP also increased in Northeast and North China when EASM strengthened,while South China showed a decline in *** indicated that GPP changed with monsoon *** to the mechanism analysis,during strong EASM,there was intense moisture convergence through alterations in the atmospheric circulation field over East China and abundant precipitation,which further contributed to the increase in *** solar radiation in Southwest China decreased with EASM enhancement,which suppressed GPP and hindered vegetation ***,the results highlight the importance of accurately predicting the impact of different EASM intensities of regional carbon fluxes.

关键词： Gross primary production Surface air temperature Precipitation Solar radiation Eastern China Carbon cycle

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Forest characteristics and population structure of a threatened palm tree Caryota obtusa in the karst forest ecosystem of Yunnan,China

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Journal of Plant Ecology 2022年第4期15卷 829-843页

作者： Cindy Q.Tang Xia Lu Min-Rui Du Shu-Li Xiao Shuaifeng Li peng-Bin Han Jia-Le Zeng Jian-Ran Wen Shi-Qian Yao You-Cai Shi Yun-Fang Li ming-chun peng Chong-Yun Wang Zhi-Ying Zhang Institute of Ecology and Geobotany College of Ecology and Environmental ScienceYunnan UniversityKunming 650504China Research Institute on Resource Insects Chinese Academy of ForestryKunming 650224China Management Office of Yunlong Tianchi National Nature Reserve GuolangDali PrefectureYunnan 672700China

Caryota obtusa of Arecaceae is a fascinating palm tree native to southwestern China,India,Myanmar,Thailand,Laos and *** is an economically important and threatened species and appears as a canopy dominant in some karst areas in *** aim to clarify the forest structure,species diversity,population status and regeneration dynamics of *** in the karst forest ecosystem of Yunnan,*** established 56 vegetation plots dominated by *** in 10 counties of southern *** on the plot data,we analyzed the community stratification,floristic composition and ***’s population *** used questionnaires to interview local people and recorded the human activity history in ***-dominated *** obtusa palm forests were distributed on limestone mountain slopes and *** were seven forest community *** stratification of each community included arborous layer,shrub layer and *** communities had rich species *** all the plots as a whole of each community type,Shannon–Wiener diversity index of either woody or herbaceous species ranged from 2.1 to *** diameter at breast height(DBH)-class frequency distribution of *** was a multimodal *** regeneration was sporadic and dependent on intermediate natural *** the current population structure,a number of *** trees with small DBHs consisted mainly of the forest communities with no or a slight degree of human *** human activities terribly hindered recruitment of ***,followed by the medium intensity of human activities.

关键词： Caryota obtusa community structure species diversity population structure regeneration dynamics human disturbance

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