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Atomic scale visualizations of low-angle grain boundary mediated plasticity by coupled dislocation climb and glide in nanoporous gold

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Nano Research 2023年第2期16卷 2622-2629页

作者： shufen Chu Junnan Jiang Xiaoran Zhao Baode Sun pan Liu Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming State Key Laboratory of Metal Matrix CompositesSchool of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Grain boundaries(GBs),as a prevalent structural characteristic,play a crucial role in the deformation of nanoporous metals with nanosized grains and ligaments.However,the fundamental understanding of GB-mediated deformation is still lacking because the plastic behavior of discrete ligaments involving GBs remains to be unknown.Here,we report atomic scale visualizations of coupled GB dislocation climb and glide in nanoporous gold ligaments with low-angle GBs via in situ tensile straining inside a Cs-corrected transmission electron microscope.The zig-zag motion paths of GB dislocations are precisely determined by real-time tracking of the movements of dislocation cores.The concurrent climb and glide of the dislocation arrays are confined to a narrow GB region,greatly enhancing GB diffusion in the bicrystal ligament.Our findings of coupled dislocation climb and glide shine a light on the room-temperature deformation of nanoporous metals and provide a time-dependent atomic-level physical image for GB engineering.

关键词： nanoporous gold dislocation climb dislocation glide low-angle grain boundaries

Can microplastics mediate soil properties,plant growth and carbon/nitrogen turnover in the terrestrial ecosystem?

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Ecosystem Health and Sustainability 2022年第1期8卷 279-294页

作者： Yao Yao Wang Lili pan shufen Li Gang Liu Hongmei Xiu Weiming Gong Lingxuan Zhao Jianning Zhang Guilong Yang Dianlin Agro-Environmental Protection Institute Ministry of Agriculture and Rural AffairsTianjinChina Key Laboratory of Original Agroenvironment Pollution Prevention and Control of Ministry of Agriculture and Rural Affairs Tianjin Key Laboratory of Agro-Environment and Agro-Product SafetyTianjinChina International Center for Climate and Global Change Research College of ForestryWildlife and EnvironmentAuburn UniversityAuburnUnited States of America

Microplastic(MP)pollution,a global environmental problem,has been recently studied in marine and freshwater environments.However,our understanding of MP effect on terrestrial ecosystems,especially carbon(C)and nitrogen(N)turnover remains poor.This review summarizes the sources and distribution characteristics of MPs in terrestrial ecosystems and explores their effects on soil properties,plant growth,C and N turnover.Once entering the terrestrial ecosystem,MPs could involve in sequestrating carbon and nitrogen by changing soil properties(e.g.,pH,soil aggregate stability,and soil porosity).MPs could exert direct influences on plants or on soil physical environment and microbial metabolic environment to indirectly affect plant growth,thus altering the quantity and quality of soil C and N inputs by shifts in plant litter and roots.The changes of the dominant bacteria phyla,related functional genes,and enzymes caused by MP pollution could affect C and N cycles.Additionally,the MP effect varies with its properties(e.g.,types,shapes,elemental composition,functional groups,released additives).Future researches should unify the standard system of MP separation,detection,and reveal the ecological effects of MPs,especially their impacts on terrestrial carbon and nitrogen cycles in the context of climate changes.

关键词： MPs terrestrial ecosystems carbon and nitrogen turnover greenhouse gases microorganisms

Impacts of climate variability and extremes on global net primary production in the first decade of the 21st century

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Journal of Geographical Sciences 2015年第9期25卷 1027-1044页

作者： pan shufen TIAN Hanqin DANGAL Shree R.S. OUYANG Zhiyun LU Chaoqun YANG Jia TAO Bo REN Wei BANGER Kamaljit YANG Qichun ZHANG Bowen International Center for Climate and Global Change Research School of Forestry and Wildlife Sciences Auburn University AL-36849 USA State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences CAS Beijing 100085 China

A wide variety of studies have estimated the magnitude of global terrestrial net primary production （NPP）, but its variations, both spatially and temporally, still remain uncertain. By using an improved process-based terrestrial ecosystem model （DLEM, Dynamic Land Ecosystem Model）, we provide an estimate of global terrestrial NPP induced by multiple environmental factors and examine the response of terrestrial NPP to climate variability at biome and global levels and along latitudes throughout the first decade of the 21st century. The model simulation estimates an average global terrestrial NPP of 54.6 Pg C yr-1 during 2000-2009, varying from 52.8 Pg C yr-1 in the dry year of 2002 to 56.4 Pg C yr-1 in the wet year of 2008. In wet years, a large increase in terrestrial NPP compared to the decadal mean was prevalent in Amazonia, Africa and Australia. In dry years, however, we found a 3.2% reduction in global terrestrial NPP compared to the decadal mean, primarily due to limited moisture supply in tropical regions. At a global level, precipitation explained approximately 63% of the variation in terrestrial NPP, while the rest was attributed to changes in temperature and other environmental factors. Precipitation was the major factor determining inter-annual variation in terrestrial NPP in low-latitude regions. However, in midand high-latitude regions, temperature variability largely controlled the magnitude of terrestrial NPP. Our results imply that pro- jected climate warming and increasing climate extreme events would alter the magnitude and spatiotemporal patterns of global terrestrial NPP.

关键词： climate variability climate extreme drought global terrestrial ecosystem net primary production（NPP）

Multi-chain Fudan-CCDC model for COVID-19—a revisit to Singapore's case

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Quantitative Biology 2020年第4期8卷 325-335页

作者： Hanshuang pan Nian Shao Yue Yan Xinyue Luo shufen Wang Ling Ye Jin Cheng Wenbin Chen School of Mathematical Sciences Fudan UniversityShanghai 200433China Shanghai Key Laboratory for Contemporary Applied Mathematics Fudan UniversityShanghai 200433China School of Mathematics Shanghai University of Finance and EconomicsShanghai 200433China Daishan County Center for Disease Control and Prevention Daishan 316200China

Background:COVID-19 has been impacting on the whole world critically and constantly since late December 2019.Rapidly increasing infections has raised intense worldwide attention.How to model the evolution of COVID-19 effectively and efficiently is of great significance for prevention and control.Methods:We propose the multi-chain Fudan-CCDC model based on the original single-chain model in[Shao et al.2020]to describe the evolution of COVID-19 in Singapore.Multi-chains can be considered as the superposition of several single chains with different characteristics.We identify the parameters of models by minimizing the penalty function.Results:The numerical simulation results exhibit the multi-chain model performs well on data fitting.Though unsteady the increments are,they could still fall within the range of±30%fluctuation from simulation results.Conclusion:The multi-chain Fudan-CCDC model provides an effective way to early detect the appearance of imported infectors and super spreaders and forecast a second outbreak.It can also explain the data from those countries where the single-chain model shows deviation from the data.

关键词： COVID-19 Singapore multi-chain Fudan-CCDC model

Methane emissions from livestock in East Asia during 1961−2019

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Ecosystem Health and Sustainability 2021年第1期7卷 147-158页

作者： Lei Zhang Hanqin Tian Hao Shi shufen pan Xiaoyu Qin Naiqing pan Shree R.S.Dangal State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina International Center for Climate and Global Change Research School of Forestry and Wildlife SciencesAuburn UniversityAuburnALUSA School of Natural Resources University of NebraskaLincolnNEUSA

Context:East Asia is a crucial region in the global methane(CH4)budget,with significant contributions from the livestock sector.However,the long-term trend and spatial pattern of CH4 emissions from livestock in this region have not been fully assessed.Methods:Here,we estimate CH4 emissions from 10 categories of livestock in East Asia during 1961-2019 following the Tier 2 approaches suggested by the 2019 Refinement to the IPCC 2006 Guidelines.Results:livestock-sourced CH4 emission in 2019 was 13.22[11.42-15.01](mean[minimum%maximum of 95-confidence interval]Tg CH4 yr-1,accounting for an increase of 231%since 1961.The contribution of slaughtered populations to total emissions increased from 3%in 1961 to 24%in 2019.Spatially,the emission hotspots were mostly distributed in eastern China,South Korea,and parts of Japan,but they tend to shift northward after 2000.Conclusion:It is necessary to use dynamic emission factors and include slaughtered populations in the estimation of livestock CH4 emissions.Regions including Northern China,Mongolia,and South Korea deserve more attention in future CH4 mitigation efforts.

关键词： CH4 emissions livestock dynamic emission factors live and slaughtered populations East Asia

pan-cancer analysis of long non-coding RNA NEAT1 in various cancers

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Genes & Diseases 2018年第1期5卷 27-35页

作者： shufen Li Jingming Li Chen Chen Rongsheng Zhang Kankan Wang State Key Laboratory of Medical Genomics and Shanghai Institute of Hematology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina McMaster University HamiltonOntarioCanada

Changes in the abundance and activity of long non-coding RNAs(lncRNAs)have an important impact on the development of cancer.The nuclear paraspeckle assembly transcript 1(NEAT1)has been reported to be overexpressed in many types of cancer since its discovery.However,inconsistencies exist as NEAT1 can also function as a tumor suppressor in certain types of cancer,such as acute promyelocytic leukemia.Here we systematically describe our current understanding of NEAT1 in tumor initiation and progression.First,we analyzed the expression patterns of NEAT1 in various normal tissues and malignant cancers using data from public data portals,the Genotype-Tissue Expression Project(GTEx)and the Cancer Genome Atlas(TCGA),together with recent progress in the study of NEAT1 in various types of cancer.Second,we discussed the functions and mechanisms of NEAT1 in modulating tumor activity.Then,the upstream transcription factors and downstream microRNA targets of NEAT1 in the transcription cascade of cancers were also summarized.These data highlight the emerging role of NEAT1 in tumorigenesis,and present promising targetable pathways and clinical opportunities for tumor prevention and classifications.

关键词： Cancer Long non-coding RNA NEAT1 pan-cancer analysis Regulation

Responses of global terrestrial water use efficiency to climate change and rising atmospheric CO_(2)concentration in the twenty-first century

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International Journal of Digital Earth 2018年第6期11卷 558-582页

作者： shufen pan Guangsheng Chen Wei Ren Shree R.S.Dangal Kamaljit Banger Jia Yang Bo Tao Hanqin Tian International Center for Climate and Global Change Research School of Forestry and Wildlife SciencesAuburn UniversityAuburnALUSA State Key Laboratory of Urban and Regional Ecology Research Center for EcoEnvironmental SciencesChinese Academy of SciencesBeijingPeople’s Republic of China Department of Plant and Soil Sciences College of AgricultureFood and EnvironmentUniversity of KentuckyLexingtonKYUSA

Terrestrial ecosystems play a significant role in global carbon and water cycles because of the substantial amount of carbon assimilated through net primary production and large amount of water loss through evapotranspiration(ET).Using a process-based ecosystem model,we investigate the potential effects of climate change and rising atmospheric CO_(2)concentration on global terrestrial ecosystem water use efficiency(WUE)during the twenty-first century.Future climate change would reduce global WUE by 16.3%under high-emission climate change scenario(A2)and 2.2%under low-emission climate scenario(B1)during 2010–2099.However,the combination of rising atmospheric CO_(2)concentration and climate change would increase global WUE by 7.9%and 9.4%under A2 and B1 climate scenarios,respectively.This suggests that rising atmospheric CO_(2)concentration could ameliorate climate change-induced WUE decline.Future WUE would increase significantly at the high-latitude regions but decrease at the low-latitude regions under combined changes in climate and atmospheric CO_(2).The largest increase of WUE would occur in tundra and boreal needleleaf deciduous forest under the combined A2 climate and atmospheric CO_(2)scenario.More accurate prediction of WUE requires deeper understanding on the responses of ET to rising atmospheric CO_(2)concentrations and its interactions with climate.

关键词： Climate change evapotranspiration net primary productivity water use efficiency

Recent patterns of terrestrial net primary production in Africa influenced by multiple environmental changes

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Ecosystem Health and Sustainability 2015年第5期1卷 34-48页

作者： shufen pan Shree R.S.Dangal Bo Tao Jia Yang Hanqin Tian International Center for Climate and Global Change Research School of Forestry and Wildlife SciencesAuburn UniversityAuburnAlabama 36849 USA

Terrestrial net primary production(NPP)is of fundamental importance to food security and ecosystem sustainability.However,little is known about how terrestrial NPP in African ecosystems has responded to recent changes in climate and other environmental factors.Here,we used an integrated ecosystem model(the dynamic land ecosystem model;DLEM)to simulate the dynamic variations in terrestrial NPP of African ecosystems driven by climate and other environmental factors during 1980-2009.We estimate a terrestrial NPP of 10.22(minimum-maximum range of 8.9-11.3)Pg C/yr during the study period.Our results show that precipitation variability had a significant effect on terrestrial NPP,explaining 74%of interannual variations in NPP.Over the 30-yr period,African ecosystems experienced an increase in NPP of 0.03 Pg C/yr,resulting from the combined effects of climate variability,elevated atmospheric CO_(2)concentration,and nitrogen deposition.Our further analyses show that there is a difference in NPP of 1.6 Pg C/yr between wet and dry years,indicating that interannual climatic variations play an important role in determining the magnitude of terrestrial NPP.Central Africa,dominated by tropical forests,was the most productive region and accounted for 50%of the carbon sequestered as NPP in Africa.Our results indicate that warmer and wetter climatic conditions,together with elevated atmospheric CO_(2)concentration and nitrogen deposition,have resulted in a significant increase in African terrestrial NPP during 1980-2009,with the largest contribution from tropical forests.

关键词： Africa climate change dynamic land ecosystem model elevated CO_(2)concentration net primary production terrestrial ecosystems

Climate extremes and ozone pollution:a growing threat to China’s food security

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Ecosystem Health and Sustainability 2016年第1期2卷 2-11页

作者： Hanqin Tian Wei Ren Bo Tao Ge Sun Art Chappelka Xiaoke Wang shufen pan Jia Yang Jiyuan Liu Ben SFelzer Jerry MMelillo John Reilly International Center for Climate and Global Change Research School of Forestry and Wildlife SciencesAuburn UniversityAuburnAlabama 36849 USA Department of Plant and Soil Sciences College of AgricultureFood and EnvironmentUniversity of KentuckyLexingtonKentucky 40506 USA Eastern Forest Environmental Threat Assessment Center USDA Forest ServiceRaleighNorth CarolinaUSA State Key Lab of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085 China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101 China Department of Earth and Environmental Sciences Lehigh University1 W.Packer DriveBethlehemPennsylvania 18015-3188 USA The Ecosystem Center Marine Biological LaboratoryWoods HoleMassachusetts 02543 USA Joint Program on Science and Policy of Global Change Massachusetts Institute of Technology77 Massachusetts AvenueCambridgeMassachusetts 02139 USA

Ensuring global food security requires a sound understanding of climate and environmental controls on crop productivity.The majority of existing assessments have focused on physical climate vari-ables(i.e.,mean temperature and precipitation),but less on the increasing climate extremes(e.g.,drought)and their interactions with increasing levels of tropospheric ozone(O3).Here we quantify the combined impacts of drought and O3 on China’s crop yield using a comprehensive,process-based agricultural eco-system model in conjunction with observational data.Our results indicate that climate change/variability and O3 together led to an annual mean reduction of crop yield by 10.0%or 55 million tons per year at the national level during 1981-2010.Crop yield shows a growing threat from severe episodic droughts and in-creasing O3 concentrations since 2000,with the largest crop yield losses occurring in northern China,causing serious concerns in food supply security in China.Our results imply that reducing tropospheric O3 levels is critical for securing crop production in coping with increasing frequency and severity of extreme climate events such as droughts.Improving air quality should be a core component of climate adaptation strategies.

关键词： China food security climate change crop yield drought tropospheric ozone(O3).