The measurement of trace elements in Antarctic snow is crucial for understanding historical atmospheric geochemical changes and circulation patterns.However,studies on their spatial distributions remain limited,partic...The measurement of trace elements in Antarctic snow is crucial for understanding historical atmospheric geochemical changes and circulation patterns.However,studies on their spatial distributions remain limited,particularly those evaluating multiple metals across several snowpits,making interpretation challenging.This study investigates the distributions and sources of trace elements-including Cd,Ba,Pb,U,Bi,V,Mn,Fe,Cu,Zn,and As-across four snowpits in the Lambert Glacier Basin,East Antarctica.The trace elements exhibit site-,element-,and season-dependent variations,with higher concentrations observed at inland sites.In contrast,δ^(18)O and ion concentrations decrease with increasing distance from the coast and elevation,underscoring the influence of marine emissions.Crustal sources primarily contributed to Ba,U,V,Mn,and Fe,while non-crustal sources predominantly contributed to Cd,Bi,Zn,Pb,Cu,and As.Positive matrix factorization(PMF)analysis indicates that trace element concentrations in Pits 2 and 3 are influenced by both crustal and non-crustal sources,while Pit 4 reflects a mixed-source influence.Pit 1(coastal site)also indicates the mixed sources with influence of a highly dynamic marine climate and environment.The PMF results reveal similarities in emission sources and atmospheric transport patterns across the snowpits,facilitating a more comprehensive interpretation of longer ice core records.Overall,this study provides valuable insights into trace element distributions and enhances our understanding of past environmental and climatic conditions.展开更多
Yellowhorn （Xanthoceras sorbifolium Bunge） is a drought-tolerant tree in the family Sapindaceae that is native to northeastern China. Its remarkably oil-rich seeds are a reliable biodiesel source. An inter simple se...Yellowhorn （Xanthoceras sorbifolium Bunge） is a drought-tolerant tree in the family Sapindaceae that is native to northeastern China. Its remarkably oil-rich seeds are a reliable biodiesel source. An inter simple sequence repeat （ISSR） analysis showed genetic variation among four artificial populations in China： two in Inner Mongolia （IM）, one in Liaoning （LN）, and one in Shandong （SD）. The average percentage of polymorphic loci was 81.25 % for these four populations. The Forest Farm in SD showed the highest number of effective alleles （Ne）, Shannon index （I）, and expected heterozygosity （He）, i.e., 1.598, 0.470, and 0.325, respectively, but the lowest number of alleles （Na） as 1.600. Based on an analysis of molecular variance, 23 % of the total genetic variation was found among populations, and 77 % within populations. A principal coordinate analysis revealed two groups （Group 1： Lindonglinchang, Jianping Agriculture Research Station and Forest Farm; Group 2： Jinjilinchang）. Understanding the genetic diversity among artificial yellowhorn populations in China, detected using ISSRs, will be useful for yellowhorn conservation and improvement. Additional arti-ficial and natural populations need to be included in the future for a country-wide perspective.展开更多
Fluorescence recovery after photobleaching(FRAP)and single particle tracking(SPT)techni-ques determine the diffusion coefficient from average diffusive motion of high-concentration molecules and from trajectories of l...Fluorescence recovery after photobleaching(FRAP)and single particle tracking(SPT)techni-ques determine the diffusion coefficient from average diffusive motion of high-concentration molecules and from trajectories of low-concentration single molecules,respectively.Lateral dif-fusion coefficients measured by FRAP and SPT techniques for the same biomolecule on cell membrane have exhibited inconsistent values across laboratories and platforms with larger dif-fusion coefficient determined by FRAP,but the sources of the inconsistency have not been investigated thoroughly.Here,we designed an image-based FRAP-SPT system and made a direct comparison between FRAP and SPT for diffusion coefficient of submicron particles with known theoretical values derived from Stokes-Einstein equation in aqueous solution.The combined iFRAP-SPT technique allowed us to measure the diffusion coefficient of the same fluorescent particle by utilizing both techniques in a single platform and to scrutinize inherent errors and artifacts of FRAP.Our results reveal that diffusion coefficient overestimated by FRAP is caused by inaccurate estimation of the bleaching spot size and can be corrected by simple image analysis.Our iFRAP-SPT technique can be potentially used for not only cellular membrane dynamics but also for quantitative analysis of the spatiotemporal distribution of the solutes in small scale analytical devices.展开更多
基金supported by the Korea Polar Research Institute grant(PE25100)the National Research Foundation of Korea grant funded by the Korean Government(NRF2022R1A2C3007047)supported by Korea Institute of Marine Science&Technology Promotion(KIMST)and by the Ministry of Oceans and Fisheries(RS-2023-00256677,PM23020).
文摘The measurement of trace elements in Antarctic snow is crucial for understanding historical atmospheric geochemical changes and circulation patterns.However,studies on their spatial distributions remain limited,particularly those evaluating multiple metals across several snowpits,making interpretation challenging.This study investigates the distributions and sources of trace elements-including Cd,Ba,Pb,U,Bi,V,Mn,Fe,Cu,Zn,and As-across four snowpits in the Lambert Glacier Basin,East Antarctica.The trace elements exhibit site-,element-,and season-dependent variations,with higher concentrations observed at inland sites.In contrast,δ^(18)O and ion concentrations decrease with increasing distance from the coast and elevation,underscoring the influence of marine emissions.Crustal sources primarily contributed to Ba,U,V,Mn,and Fe,while non-crustal sources predominantly contributed to Cd,Bi,Zn,Pb,Cu,and As.Positive matrix factorization(PMF)analysis indicates that trace element concentrations in Pits 2 and 3 are influenced by both crustal and non-crustal sources,while Pit 4 reflects a mixed-source influence.Pit 1(coastal site)also indicates the mixed sources with influence of a highly dynamic marine climate and environment.The PMF results reveal similarities in emission sources and atmospheric transport patterns across the snowpits,facilitating a more comprehensive interpretation of longer ice core records.Overall,this study provides valuable insights into trace element distributions and enhances our understanding of past environmental and climatic conditions.
基金supported by the Cooperative Research Program for Agriculture Science & Technology Development(Project no.PJ01117902) of the National Institute of Horticultural and Herbal Science,RDA,Republic of Koreathe Ministry of Education,People’s Republic of China(Program No.MS2012DBLY017 for Foreign Distinguished Scientists of the Ministry of Education)the Research Foundation of Kangwon National University,Republic of Korea
文摘Yellowhorn （Xanthoceras sorbifolium Bunge） is a drought-tolerant tree in the family Sapindaceae that is native to northeastern China. Its remarkably oil-rich seeds are a reliable biodiesel source. An inter simple sequence repeat （ISSR） analysis showed genetic variation among four artificial populations in China： two in Inner Mongolia （IM）, one in Liaoning （LN）, and one in Shandong （SD）. The average percentage of polymorphic loci was 81.25 % for these four populations. The Forest Farm in SD showed the highest number of effective alleles （Ne）, Shannon index （I）, and expected heterozygosity （He）, i.e., 1.598, 0.470, and 0.325, respectively, but the lowest number of alleles （Na） as 1.600. Based on an analysis of molecular variance, 23 % of the total genetic variation was found among populations, and 77 % within populations. A principal coordinate analysis revealed two groups （Group 1： Lindonglinchang, Jianping Agriculture Research Station and Forest Farm; Group 2： Jinjilinchang）. Understanding the genetic diversity among artificial yellowhorn populations in China, detected using ISSRs, will be useful for yellowhorn conservation and improvement. Additional arti-ficial and natural populations need to be included in the future for a country-wide perspective.
基金This work was supported by grants from the National Research Foundation(NRF)(NRF2019R1A2C2088973)funded by the Ministry of Educationthe Korea Evaluation Institute of Industrial Technology(KEIT)(20011377)funded by the Ministry of Trade,Industry&Energy,Republic of Korea.
文摘Fluorescence recovery after photobleaching(FRAP)and single particle tracking(SPT)techni-ques determine the diffusion coefficient from average diffusive motion of high-concentration molecules and from trajectories of low-concentration single molecules,respectively.Lateral dif-fusion coefficients measured by FRAP and SPT techniques for the same biomolecule on cell membrane have exhibited inconsistent values across laboratories and platforms with larger dif-fusion coefficient determined by FRAP,but the sources of the inconsistency have not been investigated thoroughly.Here,we designed an image-based FRAP-SPT system and made a direct comparison between FRAP and SPT for diffusion coefficient of submicron particles with known theoretical values derived from Stokes-Einstein equation in aqueous solution.The combined iFRAP-SPT technique allowed us to measure the diffusion coefficient of the same fluorescent particle by utilizing both techniques in a single platform and to scrutinize inherent errors and artifacts of FRAP.Our results reveal that diffusion coefficient overestimated by FRAP is caused by inaccurate estimation of the bleaching spot size and can be corrected by simple image analysis.Our iFRAP-SPT technique can be potentially used for not only cellular membrane dynamics but also for quantitative analysis of the spatiotemporal distribution of the solutes in small scale analytical devices.
