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Legacy effects of historical woodland changes on contemporary plant functional composition

Forest Ecosystems 2023年第5期10卷 569-578页

作者： Ji-Zhong Wan chun-jing Wang State Key Laboratory of Plateau Ecology and Agriculture Qinghai UniversityXining 810016China Departamento de Ecología Facultad de Ciencias BiologicasPontificia Universidad Catolica de ChileCP 8331150SantiagoChile Centro de Cambio Global UC Facultad de Ciencias BiologicasPontificia Universidad Catolica de ChileCP 8331150SantiagoChile

Considering the legacy of plant functional composition can help assess ecosystem functions and ecosystem services across different spatial scales under land cover *** plants likely respond to natural and anthropogenic perturbations due to historical events(e.g.,agricultural development),thus contemporary plant functional composition may be explained by historical woodland change,a type of land cover *** propose that historical woodland changes may have legacy effects on contemporary plant functional ***,we used partial least squares regression and linear mixed model analyses to test this assumption by coupling data on community weighted means(CWM)and community weighted variance(CWV)of vegetation plots and calculating the time of woodland existence across different periods from AD 0 to *** found that the legacy effects of historical land cover changes on CWM and CWV during the existence time of woodland,particularly from AD 0 to 900,were drivers of contemporary plant functional composition at large spatial ***,historical woodland changes can affect contemporary plant functional composition,depending on the biome ***,the CWM of plant height,seed mass,and seed length showed the strongest correlations with woodland changes from AD 1910 to 2010 in tropics with year-round rain,and the CWM of leaf traits correlated with woodland changes from AD 0 to 1700 in tropics with summer *** study provides the effective evidence on the legacy of historical woodland changes and the effects on contemporary plant functional composition,which is crucial with respect to effective management of plant diversity and assessing ecosystem functions and services from local to global scales over time.

关键词： Biome Community weighted means Global scale Historical woodland Land cover Plant functional trait

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A Method for Effective Population Transfer in U Vapor with Doppler Effect and Collision

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Chinese Physics Letters 1996年第8期13卷 590-593页

作者： NING Xi-jing jing chun-yang LIN Fu-cheng Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800

We proposed a method for effective population transfer in an atomic vapor with Doppler effect and *** this method,we have demonstrated that an efficient population transfer occurs in ^(238)U vapor produced in a hollow-cathode discharge tube.A numerical calculation with density matrix agrees well with our experimental result and indicates that the method can be used to raise the efficiency of atomic vapor isotope separation.

关键词： separation method collision

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Potential impacts of climate change on dengue fever distribution using RCP scenarios in China

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Advances in Climate Change Research 2019年第1期10卷 1-8页

作者： FAN jing-chun LIU Qi-Yong School of Public Health Gansu University of Chinese MedicineLanzhou730000China State Key Laboratory of Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatinent of Infectious DiseasesNational Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and Prevention(China CDC)Beijing102206China Shandong University Climate Change and Health Center School of Public HealthShandong UniversitJinan250012China

This study projected dengue distribution risk map using representative concentration pathways(RCP2.6,RCP4.5,RCP6.0,RCP8.5)in China in 2020s,2030s,2050s and *** on the biological characteristics of Aedes albopictus and the dengue epidemic process,dengue transmission biological model was developed to project the risk epidemic *** temperature data in 1981-2016 at 740 stations and grid data of 0.5°×0.5°(15°-55.5°N,70°-140.5E)under selected RCPs in 2020s,2030s,2050s and 2100s were *** to 142 counties and 168 million people living in the projected high risk area of dengue in the climate condition of 1981-2016,dengue high risk areas in China would expand under same RCP scenarios in the 21st century with time past except RCP2.6 with a turning down point in *** under RCP8.5 which global mean temperature would increase by 4.9 C till 2100s,the high risk area and population for dengue transmission would expand additional 34 counties(20 million)in 2020s,114 counties(60 million)in 2030s,208 counties(160 million)in 2050 and 456 counties(490 million)in 2100s respectively than those of *** RCP8.5 in 2100s,the population and expanded high risk areas would increase 4.2-fold and 2.9-fold than the 1981-2016 *** newly added high risk areas should prepare for controlling and preventing dengue in different period according to projected dengue risk map.

关键词： Dengue fever Climate change Aedes albopictus Representative concentration pathways(RCPs) Risk distribution

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Influence of Megaregolith on the Thermal Evolution of Mercury's Silicate Shell

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Research in Astronomy and Astrophysics 2022年第3期22卷 271-284页

作者： jing-chun Xie Mian Zhang Cheng-Li Huang Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China CAS Key Laboratory of Planetary Sciences Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

A so-called megaregolith layer that is considered to be produced by continuous impacts in Mercury’s early stages is integrated into the thermal evolution models of Mercury to study its influence on the thermal evolution of Mercury’s silicate *** research first implements a one-dimensional parametric global thermal evolution *** results indicate that megaregolith directly affects the thermal evolution of Mercury’s silicate shell by virtue of its good insulation *** way megaregolith exerts its influence is by prolonging the process of partial melting and reducing the heat loss,resulting in a thicker crust and thinner stagnant *** for the deep parts of the silicate shell,it is suggested that more energy is taken away from the mantle due to the longer partial melting,leading to lower temperatures below the crust compared with the case in the absence of megaregolith,which further helps to advance the formation time of the inner core and promote its final *** addition,we also carry out a simplified two-dimensional mantle convection simulation as a supplement to the one-dimensional *** two-dimensional simulation depicts a typical mantle plume fractional melting *** calculations indicate that megaregolith may be key to the long-term volcanic activities on *** far as the megaregolith itself is concerned,the thermal structure of this particular layer is more sensitive to thermal conductivity,suggesting that for such a highly fragmented structure,the thermal conductivity coefficient plays a key role in its *** work emphasizes the importance of megaregolith to the evolution of Mercury.

关键词： planets and satellites:terrestrial planets planets and satellites:physical evolution planets and satellites:interiors

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Enhanced Phase Transition in Poly(ethylene glycol) Grafted Butene-1 Copolymers

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Chinese Journal of Polymer Science 2023年第3期41卷 414-421,I0008页

作者： Ya-Hui Lou Wei Li chun-jing Qv Zhe Ma Tianjin Key Laboratory of Composite and Functional Materials and School of Materials Science and EngineeringTianjin UniversityTianjin 300072China

In the present work,a series of poly(ethylene glycol) grafted polybutene-1 copolymers(PB-g-PEG) were designed and successfully synthesized with reaction intermediate method,of which the branch densities and length could be tuned *** branch density varied from 0.39 mol% to 1.23 mol% and the branch length was tuned by employing PEG number-averaged molecular weight(Mn) from 350 Da to 750 Da and 1000 *** non-isothermal crystallization and phase transition behaviors of these butene-1 copolymers with varying branches were systematically explored by differential scanning *** results first showed that compared with the linear polybutene-1 homopolymer,presence of steric 4-[4-(trimethylsilylalkynyl)-phenyl]-1-butene(TMS) groups suppressed crystallization and phase transition of ***,the introduction of long poly(ethylene glycol)(PEG) branches with M_(n)=350-1000 Da not only elevated the peak temperature of the non-isothermal crystallization but also enhanced the Ⅱ-Ⅰ phase transition,with respect to copolymers with TMS ***,the quantitative correlations between phase transition kinetics with the branch parameters(density and length) were *** was found that the phase transition presents a non-monotonic trend with increasing branch density and branch *** this case,the optimal branch density and length obtained were 0.77 mol% and 750 Da,*** the small angle X-ray scattering and transmission electron microscopy,a direct correlation between the phase transition kinetics and the long periodicity of separated phase was obtained,which may be due to the increased internal stress and facilitated stress transport.

关键词： Polybutene-1 copolymer Crystallization kinetics Phase transition Phase separation

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Memory Effect of Crystallization in 1-Butene/α-olefin Copolymers

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Chinese Journal of Polymer Science 2022年第6期40卷 576-583页

作者： chun-jing Qv Wei Li Rui-Jun Zhao Zhe Ma Tianjin Key Laboratory of Composite and Functional Materials and School of Materials Science and EngineeringTianjin UniversityTianjin 300072China

The macromolecular architecture is the crucial factor in determining the arrangement of the ordering structures,which,because of the multiscale feature,may exhibit distinct melting behaviors and induce the so-called memory effect to affect the following *** present,the correlation between the occurrence of memory effect and the intrinsic molecular structure is still far from the comprehensive *** this work,four kinds of 1-butene/α-olefin random copolymers were designed and synthesized using the(pyridyl-amino)hafnium catalyst to introduce the different *** branch length was precisely controlled by the specific α-olefin comonomers,which include 1-hexene,1-decene,1-tetradecene,and 1-octadecene,while the branch density was tuned by the *** expected,the incorporation of α-olefin co-units to poly(1-butene)backbone decreases the non-isothermal crystallization kinetics and the degree of *** interestingly,the resulting linear branch can induce the occurrence of memory effect and the threshold concentration of co-units(i.e.,branch density)decreases with increasing the branch *** on the results of these 1-butene/α-olefin copolymers with designable branches,a direct correlation with the occurrence of memory effect and the fraction of amorphous region was established,which quantitatively indicates the degree of local segregation of the crystallized poly(1-butene)sequences by theα-olefin co-units.

关键词： Memory effect 1-Butene/α-olefin copolymer Linear branch Crystallinity

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Synthesis of new penicillin derivatives as drug-like molecules for biological screening

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Chinese Chemical Letters 2015年第1期26卷 113-117页

作者： chun-jing Liu Dinah Dutta Lester Mitscher Higuchi Biosciences Center The University of Kansas Department of Medicinal Chemistry The University of Kansas

Chemical modification of penicillin β-lactam ring was *** thiazolidine amides were produced through N4-C7 β-lactam ring opening of penicillin V methyl ester with various aliphatic,aromatic,and heterocyclic primary *** 8-hydroxypenillic acid derivatives with side chains of methyl,propyl,benzyl,and diethylaminoethyl groups were yielded via β-lactam ring rearrangement from6-aminopenicillanic acid（6-APA）.Parallel synthetic methods were used for the alkylation of8-hydroxypenillic acid and β-lactam ring opening of penicillin V methyl *** biological activities of the compounds were evaluated.

关键词： Penicillin Rearrangement β-Lactam antibiotics Nucleophilic ring opening

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COMPUTATION FORMULAS OF GENERALIZED INVERSE PAD APPROXIMANTS USING FOR SOLUTION OF INTEGRAL EQUATIONS

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Applied Mathematics and Mechanics(English Edition) 2001年第9期22卷 1057-1063页

作者： GU Chuan-qing(顾传青) LI chun-jing(李春景) Department of Mathematics Shanghai University Shanghai 200436 P R China Department of Mathamatics Tongji University Shanghai 200331 P R China

For the generalized inverse function-valued Pade approximants, its intact computation formulas are given. The explicit determinantal formulas for the denominator scalar polynomials and the numerator function-valued po... 详细信息

关键词： Pade approximant determinantal formula existence integral equation

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Synthesis and Anti-leukemia Evaluation of Tetrahydro-4H-pyrano[3,2-c]pyridines and Corresponding Anti-CD14 Monoclonal Antibody Conjugates

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Chemical Research in Chinese Universities 2013年第6期29卷 1104-1109页

作者： SUN Chuan-wen WANG jing PANG chun-cheng LI jing XIAO Di College of Life and Environment Sciences Shanghai Normal University Shanghai 200234 P.R.China

A series of novel tetrahydro-4H-pyrano[3,2-c]pyridines（3a-3p） were synthesized and found to possess potent antiproliferative activity against leukemia K562 cells in vitro. Preliminary bioassay indicates that compounds 3a and 3e afford the best activity, the IC50 values of them were 6.93 and 7.51μg/mL, respectively, which were lower than that of the anticancer drug 5-FU（1C50=8.56μg/mL）. To reduce the toxicity of compounds 3a-3p to the prolife- ration of normal bematopoietic cells, a tumor targeted CD14 monoclonal antibody（McAb） was used in conjugation with compounds 3a--3p to get conjugates 4a--4p, respectively. The inhibitory activities of conjugates 4a--4p toward K562 cells were discovered to approach those of compounds 3a--3p. In the presence of CD14 McAb, tumor cells were found to be much more susceptible to conjugates 3a--3p than normal hematopoietic cells. Therefore, the toxicity of conjugates 4a--4p to normal hematopoietic cells declined obviously. For example, as for the toxicity of compound 3a compared with that of compound 4a, the value of ICs0 increased from 35.90 μmol/L to 39.52 μmol/L.

关键词： Tetrahydro-4H-pyrano[3,2-c]pyridine Leukemia K562 cell Anti-CDl4 monoclonal antibody(McAb) Conjugate Inhibitory Toxicity

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Melilite-derived mineral inclusions in chromite from the Gaositai complex: Implications for an extensional tectonic setting in Early Permian at the north North China Craton

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Science China Earth Sciences 2016年第3期59卷 583-589页

作者： SHAO Ji An TIAN Wei WEI chun jing ZHU Wen Ping Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University

The Early Permian mafic-ultramafic concentrically zoned Gaositai intrusion at Chengde, on the northern margin of the North China Craton(NCC), is a cumulative complex emplaced along a giant fracture that penetrates deeply into the continental lithosphere. Melt inclusions are present in chromite crystals from the inner dunite and chromitite zones of the Gaositai complex. The melt inclusions have experienced post-trap crystallization and resulted in multiple mineral phases, including melilite, garnet, phlogopite, magnesite and apatite, which can indicate the liquidus minerals of the primitive magma. The characteristics of the melilite+melanite+clinopyxene assemblage indicate that the primary parental magma was highly undersaturated and derived from an alkali-rich mantle source. The crystallization of phlogopite, magnesite and apatite suggests a primary magma rich in K, H_2O and CO_2. When compared with experimental data, the primary magma of the Gaositai intrusion is concordant with a kamafugite magma originating from partial melting of enriched mantle with H_2O and CO_2 at pressures greater than 2.7 GPa. This magmatic process would have been related to extensional thinning of the continental lithosphere. The Gaositai primary magmas have high Nb/La ratios, which are similar to those of ocean island basalts, but different from arc-related magmas. This suggests that the northern margin of the NCC was not an active continental margin of the Paleo-Asian Ocean subduction zone during the Early Permian: an extensional tectonic setting during the emplacement of the Gaositai intrusion is more likely.

关键词： Melt Inclusion Melilite Primary melt Extension Continental lithosphere North China Craton

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