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A new method to prepare clean cuticular membrane from fossil leaves with thin and fragile cuticles

science China Earth sciences 2011年第2期54卷 223-227页

作者： WANG Li1,2 & LENG Qin1,3 1 State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of sciences,Nanjing 210008,China 2 Graduate School of Chinese Academy of sciences,Beijing 100049,China 3 department of science and technology,bryant university,smithfield ri 02917,usa State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Graduate School of Chinese Academy of sciences Beijing China department of science and technology Bryant University Smithfield USA

Leaf cuticle analysis has long been a powerful tool for fossil plant identification, systematics, and palaeoclimatological recon- struction. In recent decades the application of stomatal frequency data that are relied on precise calculation of stomata on plant fossil cuticles to reconstruct ancient atmospheric CO2 concentration made the preparation of cuticular membrane with sufficient size a critical technique in palaeoclimatological research. However, for plants with originally thin and fragile cuticles, e.g., most deciduous plants, conventional techniques sometimes fail to obtain cuticular membranes with sufficient size, or sometimes unable to recover any. This has largely hampered the usage of fossil cuticle analysis in palaeobotanical and palaeo- climatological research. Here, we describe a new method using clear nail polish as a medium to ＂strengthen＂ the originally thin and fragile cuticles prior to maceration procedures. We demonstrate the method by using middle Eocene Metasequoia fossils that were notorious for the difficulty of recovering large-sized clean cuticular membranes due to their thin and fragile nature. Metasequoia, with well-documented and widely-distributed fossil records since the Late Cretaceous and with a living repre- sentative, 114. glyptostroboides, as a comparative reference, bas been widely used as a model genus for the study of evolution of plants, palaeoclimatological reconstruction, and plant adaptation to climate changes. But its deciduous habit produces thin cuticles and makes the preparation of clean cuticular membranes a tedious process. The new method successfully allows us to recover its delicate cuticular membranes with sufficient sizes for SEM observation and stomatal frequency analysis.

关键词： fossil leaf cuticle Metasequoia new method thin and fragile cuticle SEM observation stomatal frequency CO2

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Molecular hydrogen isotope analysis of living and fossil plants—Metasequoia as an example

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Progress in Natural science:Materials International 2009年第8期19卷 901-912页

作者： Hong Yang a,b, Qin Leng a,c a department of science and technology, College of Arts and sciences, bryant university, smithfield, ri 02917, usa b department of Geology and Geophysics, Yale university, New Haven, CT 06520, usa c LPS, Nanjing Institute of Geology and Palaeontology, CAS, Nanjing 210008, China department of science and technology College of Arts and Sciences Bryant University Smithfield RI 02917 USA department of Geology and Geophysics Yale University New Haven CT 06520 USA LPS Nanjing Institute of Geology and Palaeontology CAS Nanjing 210008 China

Molecular hydrogen isotope analysis preformed on modern and fossil plants has made a significant impact on diverse research fields in biology and geology. Using living and fossil Metasequoia as an example, we review the technology of online GC-IRMS that made the molecular analysis of hydrogen isotope possible and discuss critical issues concerning with the studies of molecular dD and its applications. The apparent hydrogen fractionation factors between lipid molecules and source water (ewater–lipid) vary across plant taxonomy and differ among biomolecules and are affected by multiple environmental factors in which precipitation dD values exercise the first order of control. Eco-physiological factors and environmental parameters are also known to influence dD in plants. Molecular hydrogen isotope analysis of chemically stable lipid molecules, such as n-alkanes, finds a wide range of applications in detecting source sediments, reconstruction of paleoclimatic parameters, inference of air-mass trajectory, as well as in petroleum industry and environmental studies.

关键词： Compound-specific dD Plant molecule Hydrogen fractionation Paleoclimate Metasequoia

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New ancient DNA sequences suggest high genetic diversity for the woolly mammoth (Mammuthus primigenius)

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Progress in Natural science:Materials International 2006年第4期16卷 379-386页

作者： YANG Shujuan, LAI Xulong, SHI Suhua, CHENG Shenghong, ZHOU Xiugao, YANG Xiujuan and YANG Hong department of Earth science, China university of Geosciences, Wuhan 430074, China department of Life science, Sun Yat-Sen university, Guangzhou 510275, China Institute of Zoology, Chinese Academy of sciences, Beijing 100080, China Heilongjiang Provincial Museum, Harbin 150001, China department of sciences and technology, College of Arts and sciences, bryant university, smithfield, Rhode Island 02917, usa and department of Geology and Geophysics, Yale university, New Haven, CT 06520, usa Institute of Zoology Chinese Academy of Sciences Beijing 100080 China department of Earth science China University of Geosciences Wuhan 430074 China department of Life science Sun Yat-Sen University Guangzhou 510275 China Heilongjiang Provincial Museum Harbin 150001 China department of sciences and technology College of Arts and Sciences Bryant Universi- ty Smithfield Rhode Island 02917 USA and Department of Geology and Geophysics Yale University New Haven CT 06520 USA)

Partial DNA sequences of cytochrome b gene (mtDNA) were successfully retrieved from Late Pleistocene fossil bone of Mammuthus primigenius collected from the Xiguitu County ( Yakeshi), Inner Mongolia Autonomous Region and from Zhaodong, Harbin of Heilongjiang Province in northern China. Two ancient DNA fragments (109 bp and 124 bp) were authenticated by reproducible experiments in two different laboratories and by phylogenetic analysis with other Elephantidae taxa. Phylogenetic analysis using these sequences and published data in either separate or combined datasets indicate unstable relationship among the woolly mammoth and the two living elephants, Elephas and Loxodonta . In addition to the short sequences used to attempt the long independent evolution of Elephantidae terminal taxa, we suggest that a high intra-specific diversity existed in Mammuthus primigenius crossing both spatial and temporal ranges, resulting in a complex and divergent genetic background for DNA sequences so far recovered. The high genetic diversity in the extinct woolly mammoth can explain the apparent instability of Elephantidae taxa on the molecular phylogenetic trees and can reconcile the apparent paradox regarding the unresolved Elephantidae trichotomy.

关键词： Mammuthus primigenius genetic diversity ancient DNA phylogenetic analysis.

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Quantitative discrimination of surface adsorbed NO_(x) species on CeO_(2) via spectrophotometry for SCR denitration investigation

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Journal of Rare Earths 2024年第6期42卷 1066-1072,I0003页

作者： Songil Sin Jiawei Ji Lijun Cheng Zhiwen Gu Chong Tan Kwangchol ri Changjin Tang School of Environment Nanjing Normal UniversityNanjing210023China department of Mining Engineering Kim Chaek University of TechnologyPyongyang999093Democratic People's Republic of Korea Laboratory of Mesoscopic Chemistry of MOE School of Chemistry and Chemical EngineeringNanjing UniversityNanjing20023China Institute of Chemical Engineering Hamhung University of Chemical EngineeringHamhungDemocratic People's Republic of Korea Jiangsu Province Engineering Research Center of Environmental risk Prevention and Emergency Response technology Nanjing210023China

CeO_(2)-based catalysts are widely investigated for selective catalytic reduction(SCR)of NO with *** of NO/O_(2) with CeO_(2) generally produces two surface species,i.e.,nitrates and ***,the explicit quantification of these two species is still ***,we reported that spectrophotometry characterization was effective in determining surface adsorbed NOx species on CeO_(2) by measuring the corresponding ions(NO_(2)-and NO_(3)^(-))dissolved in aqueous *** results show that both nitrate(-NO_(3))and nitrite(-NO_(2))species can be quantitatively evaluated and the accuracy is verified by calibrating with NOx-TPD *** transfer of adsorbed NOx from catalyst surface to aqueous solution is confirmed and the dissolution process can be accelerated by ultrasonic ***,useful information related to evolution of surface NOx species under various conditions(O_(2) treatment,different adsorption temperature and duration)and over different catalysts(Fe_(2)O_(3),MnO_(2) and MnOx—CeO_(2))are *** result of present study demonstrates the potential of spectrophotometry for quantitative discrimination of surface NOx species on CeO_(2) and other oxide-based materials,which is conducive to mechanism analysis of SCR reaction.

关键词： Quantitative evaluation Spectrophotometry analysis Nitrate species Nitrite species CeO_(2)catalyst NH_(3)-SCR

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Pyrite framboids associated with the Mesozoic Jehol Biota in northeastern China:Implications for microenvironment during early fossilization

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Progress in Natural science:Materials International 2003年第3期 48-54页

作者： LENG Qin and YANG Hong (1. Nanjing Institute of Geology & Palaeontology, Chinese Academy of sciences, Nanjing 210008, China 2. department of Geological sciences, Brown university, Providence, ri 02912, usa 3. department of science & technology, bryant College, smithfield, ri 02917, usa) Nanjing Institute of Geology & Palaeontology，Chinese Academy of sciences，Nanjing 210008，China department of Geological sciences，Brown university，Providence，ri 02912，usa department of science & technology，bryant College，smithfield，ri02917，usa

Despite of the recent influx of reports describing important fossil specimens from the Mesozoic Jehol Biota, detailed in-formation on the mechanism of fossilization and paleoenvironment in which these fossils were deposited is scanty. We present an analysis ofmicroenvironment based upon scanning electron microscope observations of in situ pyrite framboids and microcrystallines of plant and ver-tebrate feather fossils in the Jehol Biota. Pyrite microcrystallines and framboids occur extensively inside and on surface of plant *** found on feathers and in sedimentary matrix were in a lower abundance. These framboids have diameters ranging from 6 μm to31μm with an average of 20μm, indicating a dysoxic aqueous condition with free oxygen level less than 30μmol/L for the microenviron-ment where these framboids were formed. The outgrowth of framboids inside plant tissues suggests the presence of water molecules andfree oxygen at the cellular level during pyritization; the relative timing betwee

关键词： framboid Jehol Biota microenvironment.

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Isorhamnetin Downregulates MMP2 and MMP9 to Inhibit Development of Rheumatoid Arthritis through SRC/ERK/CREB Pathway

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Chinese Journal of Integrative Medicine 2024年第4期30卷 299-310页

作者： LIU Xiao-rong LI Shuo-fu MEI Wen-ya LIU Xiang-dan ZHOU ri-bao College of Pharmacy Hunan University of Chinese MedicineChangsha(410208)China department of Orthopaedics The First Hospital of Hunan University of Chinese MedicineChangsha(410007)China

Objective To investigate the effect of isorhamnetin on the pathology of rheumatoid arthritis(RA).Methods Tumor necrosis factor(TNF)-α-induced fibroblast-like synoviocytes(FLS)was exposed to additional isorhamnetin(10,20 and 40µmol/L).Overexpression vectors for matrix metalloproteinase-2(MMP2)or MMP9 or SRC were transfected to explore their roles in isorhamnetin-mediated RA-FLS ***-FLS viability,migration,and invasion were ***,a collagen-induced arthritis(CIA)rat model was *** were randomly divided to sham,CIA,low-,medium-,and high-dosage groups using a random number table(n=5 in each group)and administed with normal saline or additional isorhamnetin[2,10,and 20 mg/(kg·day)]for 4 weeks,*** index was calculated and synovial tissue inflammation was determined in CIA *** levels of MMP2,MMP9,TNF-α,interleukin-6(IL-6),and IL-1β,as well as the phosphorylation levels of SRC,extracellular regulated kinase(ERK),and cyclic adenosine monophosphate response element-binding(CREB),were detected in RA-FLS and synovial *** docking was also used to analyze the binding of isorhamnetin to *** In in vitro studies,isorhamnetin inhibited RA-FLS viability,migration and invasion(Pritis index scores(P<0.05)and alleviated synovial *** reduced the levels of MMP2,MMP9,TNF-α,IL-6,and IL-1β,as well as the phosphorylation of SRC,ERK,and CRE

关键词： rheumatoid arthritis isorhamnetin SRC/ERK/CREB matrix metalloproteinase

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Influence and Analysis of Concentrate Degree of Plasma Arc for Heat Process of Hardening Treatment

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材料热处理学报 2004年第5B期25卷 779-782页

作者： WANGShuo-gui YANHong-ri wdepartmentofPrecisionMachineryandPrecisionInstrument UniversityofScienceandTechnologyofChinaHefeiChina

According to the practicable model of the plasma arc surface quench, the influence law of the heat process, cooling course, temperature field about surface quench treatment by plasma arc due to the concentrate degree of plasma arc heat source are discussed in this paper. It shows that the concentrate degree of plasma arc heat source can change the width of the hardening zone and can not change the maximum harden depth. With the increase of the concentrate degree, the area of the heat influence zone is decreased and its shape is narrowed after the heat source. Relative to cooling rate, the influence of the heat source concentrate degree for heat absorption is bigger. The correctness of the practical model are proved with experimental results for quench hardening of steel by plasma arc.

关键词：等离子电弧热源表面淬火硬化处理集中度

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Anatomical variations of living and fossil Liquidambar leaves:A proxy for paleoenvironmental reconstruction

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science China Earth sciences 2011年第4期54卷 493-508页

作者： XIAO Liang 1,2,3,4,SUN BaiNian 1,2,,LI XiangChuan 1,REN WenXiu 1 &JIA Hui 1 1 Key Laboratory of Western China's Environmental Systems of the Ministry of Education and College of Earth and Environment science,Lanzhou university,Lanzhou 730000,China 2 State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of sciences,Nanjing 210008,China 3 College of Arts and sciences,bryant university,smithfield ri 02917,U.S.A. 4 Key Laboratory of Western China's Mineral Resources and Geological Engineering of Ministry of Education,Chang’an university,Xi’an 710054,China Key Laboratory of Western China’s Environmental Systems of the Ministry of Education and College of Earth and Environment science Lanzhou University Lanzhou China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China College of Arts and sciences Bryant University Smithfield USA Key Laboratory of Western China’s Mineral Resources and Geological Engineering of Ministry of Education Chang’an University Xi’an China

Based on living ***,we have established that such epidermal cell properties as epidermal cell circumference(Circum.) ,undulation index(UI) ,epidermal cell area(EA) on both upper and lower epidermis and the corresponding epidermal cell density(ED) ,are suitable to differentiate between sun and shade ***,stomatal properties on the lower epidermis,including stomatal length(SL) ,stomatal pore length(PL) and the corresponding stomatal density(SD) ,are reliable parameters to identify sun/shade *** this anatomical approach was applied to 18 leaf remains of *** from the Miocene Xiannanshan Formation,Zhejiang Province(eastern China) ,and the fossil leaves were sorted into two groups,namely,sun and shade *** indicates that anatomical differences between sun and shade leaves found in living species could be used for fossil ***,the variation of UI between sun and shade morphotypes is larger on the upper epidermis as compared with the lower epidermis,showing that the UI on the upper epidermis is more sensitive to environmental *** addition,anatomical features are more variable in sun leaves than in shade leaves for both modern and fossil Liquidambar,suggesting sun leaves may be more sensitive to environmental *** leaves can then be a better indicator of paleoenvironmental ***,stomatal parameters of sun morphotype should be adopted on reconstructing paleoenvironments using Liquidambar leaf *** the other hand,the three-lobed fossil *** leaf assemblage in the Xiananshan Formation is represented by an almost similar percentage of sun and shade morphotypes(56%and 44%,respectively) ,which is attributed to the short transport before *** a result,identifying sun/shade morphotypes are very useful in reconstructing paleoenvironments based on fossil leaves of Liquidambar.

关键词： Liquidambar formosana Liquidambar miosinica leaf anatomy the Miocene Xiananshan Formation sun and shade leaves

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Four decades of full-scale nitrous oxide emission inventory in China

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National science Review 2024年第03期11卷 137-149页

作者： Minqi Liang Zheyan Zhou Peiyang Ren Han Xiao Xu-ri Zhongmin Hu Shilong Piao Hanqin Tian Qing Tong Feng Zhou Jing Wei Wenping Yuan School of Atmospheric sciences Guangdong Province Data Center of Terrestrial and Marine Ecosystems Carbon Cycle Sun Yat-sen University State Key Laboratory of Tibetan Plateau Earth System Resources and Environment Institute of Tibetan Plateau Research Chinese Academy of Sciences Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province Hainan University Sino-French Institute for Earth System science College of Urban and Environmental SciencesPeking University Schiller Institute for Integrated science and Society Department of Earth and Environmental Sciences Boston College Institute of Energy Environment and Economy Tsinghua University Southern Marine science and Engineering Guangdong Laboratory(Zhuhai)

China is among the top nitrous oxide（N2O）-emitting countries, but existing national inventories do not provide full-scale emissions including both natural and anthropogenic sources. We conducted a four-decade（1980–2020） of comprehensive quantification of Chinese N2O inventory using empirical emission factor method for anthropogenic sources and two up-to-date process-based models for natural sources. Total N2O emissions peaked at 2287.4（1774.8–2799.9） Gg N2O yr-1in 2018, and agriculture-developed regions, like the East, Northeast, and Central, were the top N2O-emitting regions. Agricultural N2O emissions have started to decrease after 2016 due to the decline of nitrogen fertilization applications, while, industrial and energetic sources have been dramatically increasing after 2005. N2O emissions from agriculture, industry,energy, and waste represented 49.3%, 26.4%, 17.5%, and 6.7% of the anthropogenic emissions in 2020,respectively, which revealed that it is imperative to prioritize N2O emission mitigation in agriculture,industry, and energy. Natural N2O sources, dominated by forests, have been steadily growing from 317.3（290.3–344.1） Gg N2O yr-1in 1980 to 376.2（335.5–407.2） Gg N2O yr-1in 2020. Our study produces a Full-scale Annual N2O dataset in China（FAN2020）, providing emergent counting to refine the current national N2O inventories.

关键词： nitrous oxide four decades anthropogenic sources natural sources

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Integer multiple quantum image scaling based on NEQR and bicubic interpolation

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Chinese Physics B 2024年第4期33卷 259-273页

作者：蔡硕周日贵罗佳陈思哲 College of Information Engineering Shanghai Maritime UniversityShanghai 201306China Research Center of Intelligent Information Processing and Quantum Intelligent Computing Shanghai 201306China College of Merchant Marine Shanghai Maritime UniversityShanghai 201306China School of Mathematics and Computational science Shangrao Normal UniversityShangrao 334001China

As a branch of quantum image processing,quantum image scaling has been widely ***,most of the existing quantum image scaling algorithms are based on nearest-neighbor interpolation and bilinear interpolation,the quantum version of bicubic interpolation has not yet been *** this work,we present the first quantum image scaling scheme for bicubic interpolation based on the novel enhanced quantum representation(NEQR).Our scheme can realize synchronous enlargement and reduction of the image with the size of 2^(n)×2^(n) by integral ***,the image is represented by NEQR and the original image coordinates are obtained through multiple CNOT ***,16 neighborhood pixels are obtained by quantum operation circuits,and the corresponding weights of these pixels are calculated by quantum arithmetic ***,a quantum matrix operation,instead of a classical convolution operation,is used to realize the sum of convolution of these *** simulation experiments and complexity analysis,we demonstrate that our scheme achieves exponential speedup over the classical bicubic interpolation algorithm,and has better effect than the quantum version of bilinear interpolation.

关键词： quantum image processing image scaling bicubic interpolation quantum circuit

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