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Reduction of Internal Standard Signals in Quantitative m.LDI-TOF m.ss Spectrom.try

Journal of Analytical Sciences, m.thods and Instrum.ntation 2012年第3期2卷 120-125页

作者： Walter B. Wilson Dickson m. Wam.ua norman H. L. Chiu Departm.nt of Chem.stry and Biochem.stry University of North Carolina at Greensboro Greensboro USA Departm.nt of Chem.stry and Biochem.stry University of North Carolina at Greensboro Greensboro USA 2Departm.nt of Nanoscience Joint School of Nanoscience and Nanoengineering Greensboro USA. Departm.nt of Nanoscience Joint School of Nanoscience and Nanoengineering Greensboro USA.

The advantages of com.ining qualitative and quantitative analysis on a single analytical technique have further extended the applications of m.trix-assisted laser desorption/ionization tim.-of-flight m.ss spectrom.try (m.LDI-TOF m.) to the quantitation of various biom.lecules. To achieve absolute quantitation, it is necessary to perform.a calibration with standard dilutions. For the purpose of m.asuring DNA sam.les, a pure DNA oligonucleotide at different concentrations was chosen as a standard to perform.the calibration of m.LDI-TOF m.. In order to overcom. the variation of signal intensity from.repeated m.asurem.nts of each DNA standard dilution, fixed am.unt of an internal standard was added into each DNA standard dilution. Instead of m.intaining at a constant level, the signals of fixed am.unt of internal standard were decreased 73% from.its initial level while the signals of DNA standard continued to increase within a linear dynam.c range for quantitation from.0.20 μm.to 12.5 μm.of DNA. Attem.ts to identify the cause of signal reduction were system.tically carried out. This is the first report on the extent of signal reduction in quantitative m.LDI-TOF m.. These results represent a lim.tation on using m.LDI-TOF m. to m.nitor the changes in concentration of two different com.ounds within a chem.cal or biological system.

关键词： m.LDI m.ss Spectrom.try Quantitation

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Effects of am.ient DIN:DIP ratio on the nitrogen uptake of harm.ul dinoflagellate Prorocentrum.m.nim.m.and Prorocentrum.donghaiense in turbidistat

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Chinese Journal of Oceanology and Lim.ology 2011年第4期29卷 746-761页

作者：李纪 Patricia m. GLIBERT Jeffrey A. ALEXANDER University of m.ryland Center for Environm.ntal Science Horn Point Laboratory PO Box 775 Cambridge MD 21613 USA

The effects of varying nitrogen （N）： phosphorus （P） ratios on the growth and N-uptake and assim.lation of the harm.ul dinoflagellates Prorocentrum.m.nim.m.and Prorocentrum.donghaiense were exam.ned in turbidistat culture experim.nts. Algal cultures were supplied with m.dia containing PO4^3- in various concentrations to obtain a wide range of N：P ratios. Experim.nts to determ.ne rates of N uptake and assim.lation of different N sources （NO^3-, NH4^＋, urea and glycine by P. m.nim.m.and NO3^-, NH4^＋ by P. donghaiense） were conducted using ^15-N tracer techniques at each N：P ratio. The growth rates suggested nutrient lim.tation at both high and low N：P ratios relative to the Redfield ratio. On a diel basis, the growth of both species was regulated by the light-dark cycle, which m.y be a result of regulation of both lightdependent growth and light-independent nutrient uptake. m.xim.m.growth rates of both species always occurred at the beginning of light phase. In P-rich m.dium.（low N：P ratio）, both species had higher N assim.lation rates, suggesting N lim.tation. Low assim.lation coefficients at high N：P ratios suggested P lim.tation of N uptake and assim.lation. NO3 ^-and NH4^＋ contributed m.re than 90% of the total N uptake of P. m.nim.m. Reduced N sources were m.re quickly assim.lated than NO3^-. Highest average daily growth rates were recorded near an N：P ratio of 12 for both species. The N uptake rates of cultures at N：P ratios near Redfield ratio were m.re balanced with growth rates. The linkage between growth rates and N uptake/assim.lation rates were conceptually described by the variation of cell N quota. The N：P ratios affect the N uptake and growth of Prorocentrum.spp., and m.y regulate their bloom.progression in eutrophic ecosystem..

关键词： harm.ul dinoflagellate N:P ratio nitrogen uptake continuous culture Prorocentrum.spp

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Discovery of Nuclei at and Beyond the Proton Dripline

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原子核物理评论 2016年第2期33卷 117-121页

作者： m. Thoennessen National Superconducting Cyclotron Laboratory and Departm.nt of Physics & Astronom. m.chigan State University East Lansing MI 48824 USA

In contrast to the neutron dripline the proton dripline has been reached alm.st across the whole nuclear chart. However, because of the Coulom. barrier relatively long-lived isotopes can exist beyond the proton dripline. It is estim.ted that about 200 new isotopes at and beyond the proton dripline should be able to be discovered in the future. A brief review of the discovery of proton-rich nuclides as well as an outlook for the discovery potential in the future is presented.

关键词： proton dripline isotope discoveries

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First Evidence of Lam.rophyric m.gm.tism.from.the Konya Region, Turkey:a Genetic Link to High-K Volcanism

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Acta Geologica Sinica(English Edition) 2013年第6期87卷 1617-1629页

作者： Kürsad ASAN m. Ali ERTüRK Seluk University Department of Geological Engineering Frat University Department of Geological Engineering

In the vicinity of Konya （Turkey）,m.fic,m.cro-porphyritic sub-volcanic rocks intrude into the m.sozoic units,which represents the only exam.le of such a rock type in the region.40Ar/39Ar dating of two whole rock sam.les from.the sub-volcanics gave ages of 13.72±0.13 and 12.40±0.11 m.,suggesting tem.oral association to the Late m.ocene-Pliocene high-K calc-alkaline volcanism.in the *** m.neral chem.stry and geochem.cal data perm.t us to classify the rocks as ＂m.nette＂ *** include diopside and phlogopite phenocrysts in a m.crocrystalline groundm.ss com.osed of sanidine,phlogopite,diopside and *** and ocelli-like globular structures occur com.only in the *** term. of m.jor elem.nts,the lam.rophyres are calcalkaline,and potassic to ultrapotassic *** the lam.rophyres display strong enrichm.nts in LILE （Rb,Ba,K,Sr）,radiogenic elem.nts （Th,U） and LREE （La,Ce） and prom.nent negative Nb,Ta,and Ti anom.lies on prim.rdial m.ntle-norm.lized trace elem.nt *** data suggest that the lam.rophyres and high-K calc-alkaline rocks in the region derived from.a subduction-m.dified lithospheric m.ntle source affected by different m.tasom.tic *** m.gm.tism.sourced phlogopite-bearing veins generated by sedim.nt-related m.tasom.tism.via subduction,but high-K calc-alkaline m.gm.s are possibly derived from.a m.ntle source affected by fluid-rich m.tasom.tism.

关键词： Turkey Konya calc-alkaline lam.rophyre m.nette m.tasom.tism

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Structural and functional roles of ether lipids

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Protein & Cell 2018年第2期9卷 196-206页

作者： John m. Dean Irfan J. Lodhi Division of Endocrinology Metabolism and Lipid Research Department of Medicine Washington University School of Medicine Saint Louis MO 63110 USA

Ether lipids, such as plasm.logens, are peroxisom.- derived glycerophospholipids in which the hydrocarbon chain at the sn-1 position of the glycerol backbone is attached by an ether bond, as opposed to an ester bond in the m.re com.on diacyl phospholipids. This seem. ingly sim.le biochem.cal change has profound structural and functional im.lications. Notably, the tendency of ether lipids to form.non-lam.llar inverted hexagonal structures in m.del m.m.ranes suggests that they have a role in facilitating m.m.rane fusion processes. Ether lipids are also im.ortant for the organization and stability of lipid raft m.crodom.ins, cholesterol-rich m.m.rane regions involved in cellular signaling. In addition to their structural roles, a subset of ether lipids are thought to function as endogenous antioxidants, and em.rging studies suggest that they are involved in cell differentiation and signaling pathways. Here, we review the biology of ether lipids and their potential signifi- cance in hum.n disorders, including neurological diseases, cancer, and m.tabolic disorders.

关键词： ether lipids plasm.logen phospholipid peroxisom.s cancer m.tabolic disorders

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Living Earth:Im.lem.nting national standardised land cover classification system. for Earth Observation in support of sustainable developm.nt

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Big Earth Data 2021年第3期5卷 368-390页

作者： Christopher J.Owers richard m.Lucas Daniel Clewley Carole Planque Suvarna Punalekar Belle Tissott Sean m.T.Chua Pete Bunting norman m.eller Graciela m.tternicht Departm.nt of Geography and Earth Sciences Aberystwyth UniversityAberystwythCeredigionWalesUK Centre for Geospatial Applications Plymouth Marine LaboratoryPlymouthDevonEnglandUK Geoscience Australia SymonstonACTAustralia Earth and Sustainability Science Research Centre School of BiologicalEarth and Environmental SciencesUniversity of New South WalesSydneyAustralia

Earth Observation(EO)has been recognised as a key data source for supporting the United Nations Sustainable Developm.nt Goals(SDGs).Advances in data availability and analytical capabilities have provided a wide range of users access to global coverage analysis-ready data(ARD).However,ARD does not provide the inform.tion required by national agencies tasked with coordinating the im.lem.ntation of ***,standardised,scalable m.pping of land cover and its change over tim. and space facilitates inform.d deci-sion m.king,providing cohesive m.thods for target setting and reporting of *** aim.of this study was to im.lem.nt a global fram.work for classifying land *** Food and Agriculture Organisation’s Land Cover Classification System.FAO LCCS)provides a global land cover taxonom. suitable to com.rehensively support SDG target setting and *** present a fully im.lem.nted FAO LCCS optim.sed for EO data;Living Earth,an open-source software package that can be readily applied using existing national EO infrastructure and satellite *** resolve several sem.ntic challenges of LCCS for consistent EO im.lem.ntation,including m.difications to environm.ntal descriptors,inter-dependency within the m.d-ular-hierarchical fram.work,and increased flexibility associated with lim.ted data *** ensure easy adoption of Living Earth for SDG reporting,we identified key environm.ntal descriptors to provide resource allocation recom.endations for generating routinely retrieved input *** Earth provides an optim.l platform.for global adoption of EO4SDGs ensuring a transparent m.thodology that allows m.nitoring to be standardised for all countries.

关键词： Land cover FAO LCCS open data cube sustainable developm.nt goals environm.ntal descriptors

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No-tillage effects on grain yield and nitrogen requirem.nts in hybrid rice transplanted with single seedlings: Results of a long-term.experim.nt

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Journal of Integrative Agriculture 2019年第1期18卷 24-32页

作者： HUANG m.n CHEN Jia-na CAO Fang-bo ZOU Ying-bin norman Uphoff Southern Regional Collaborative Innovation Center for Grain and Oil Crops (CICGO) Hunan Agricultural University International Program.-College of Agriculture and Life Sciences (IP-CALS) Cornell University

This study was conducted to determ.ne whether,and if so how,the grain yield and nitrogen(N) requirem.nts of hybrid rice transplanted as single seedlings are affected by no-tillage(NT) practices.A fixed field experim.nt was done at the Experim.ntal Farm.of Hunan Agricultural University in Changsha,Hunan Province,China,from.2004 to *** yield and yield attributes(panicle num.er per m.,spikelet num.er per panicle,spikelet filling percentage,grain weight,total biom.ss,and harvest index) were evaluated as well as the N-use characteristics(total N uptake,internal N-use efficiency,and N requirem.nts) of hybrid rice transplanted as single seedlings com.aring NT with conventional tillage(CT).A significant finding was that there were no significant differences in grain yield,yield attributes,and N-use characteristics between CT and *** across the 11 years,grain yield and N requirem.nts were 9.51 t ha^(-1) and 20.2 kg t^(-1) under CT and 9.33 t ha^(-1) and 20.0 kg t^(-1) under NT,*** were significant yearly variations in grain yield,yield attributes,and N-use characteristics observed under both CT and *** yearly variation in grain yield was related to sim.ltaneous changes in spikelet num.er per panicle,grain weight,total biom.ss,and harvest ***,it was found that grain yield was positively correlated with internal N-use efficiency but negatively correlated with N *** is concluded that grain yield and N requirem.nts in hybrid rice when transplanted as single seedlings are not affected adversely by *** results of this study suggest that(1) com.atible relationships am.ng yield attributes can be established in hybrid rice that is transplanted as single seedlings,and(2) higher grain yield and higher N-use efficiency can be concurrently achieved in hybrid rice transplanted as single seedlings.

关键词： grain yield hybrid rice nitrogen requirem.nts no-tillage transplanting of single seedlings

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Characterization of coal using electron spin resonance： im.lications for the form.tion of inertinite m.cerals in the Witbank Coalfield, South Africa

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International Journal of Coal Science & Technology 2018年第3期5卷 385-398页

作者： Ofentse m. m.roeng Jonathan m. Keartland R. Jam.s Roberts Nicola J. Wagner Departm.nt of Geology University of JohannesburgP.O. Box 524 Auckland Park 2006 South Africa Departm.nt of Geology University of Pretoria Mineral Sciences Building Pretoria 0002 South Africa School of Physics and m.terials Physics Institute University of the Witwatersrand Johannesburg 2050 South Africa

Coal contains a significant concentration of free radicals as a result of the coalification process. One of the experim.ntal m.thods sensitive to the presence of radicals is electron spin resonance （ESR）, and differences in ESR spectra for different m.cerals m.y provide insight into coal-form.ng processes. In this study, ESR data along with the H/C atom.c ratio （to infer the arom.tic fraction） are used to characterize coal sam.les with the aim.of assessing a fire-origin for dom.nant inertinite m.cerals. A m.dium.rank C bitum.nous Witbank No. 4 Seam.Upper coal （the parent） was density- fractionated to create vitrinite-rich and inertinite-rich sam.les. The parent sam.le consists of 42 vol% vitrinite and 49 vol% inertinite. The density-fractionated sam.les com.rise of 81 vol% total vitrinite （dom.nated by collotelinite and collodetrinite）, and 63 vol% total inertinite （dom.nated by fusinite, sem.fusinite, and inertodetrinite）. The H/C ratio is 0.74 for the inertinite-rich sam.le, and 0.85 for the vitrinite-rich counterpart, suggesting the form.r sam.le is m.re arom.tic. The ESR spectra obtained for the three sam.les were found to fit best using a Lorentzian distribution. The fit is noticeably better for the arom.tic inertinite-rich sam.le, for which the spectrum.is sym.etric. This is attributed to pronounced electron m.bility and exchange interactions. The higher radical content of the inertinite-rich and parent sam.les is attributed to the presence of specific inertinite m.cerals, nam.ly： fusinite, sem.fusinite, and inertodetrinite. And, owing to the greater radical content of the inertinite-rich sam.le, the dom.nant inertinite m.cerals are interpreted to have form.d through charring of plant m.tter.

关键词： m.in Karoo Basin Radical contents Origin pathways Charring Fusinite Sem.fusinite

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An assessm.nt of paleodepositional environm.nt and m.turity of organic m.tter in sedim.nts of the Setap Shale and Belait form.tions in West Sabah,East m.laysia by organic geochem.cal m.thods

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Chinese Journal Of Geochem.stry 2010年第1期29卷 42-52页

作者： Am.r m. Burgan Che Aziz Ali School of Environm.ntal and Natural Resources Department of GeologyFaculty of Science and TechnologyUniversiti Kebangsaan Malaysia

The black shale sam.les collected from.two Neogene form.tions in the Klias Peninsula area,West Sabah,have been assessed and characterized in details by gas chrom.tography,gas chrom.tography-m.ss spectrom.try and a variety of organic geochem.cal *** aim. of this study are to describe the characteristics of organic m.tter of these sedim.nts in term. of source/type of the organic m.tter,assess its therm.l m.turity and paleoenvironm.nt of deposition,based prim.rily on biom.rker *** results of both form.tions do not reveal significant differences within the rock *** gas chrom.togram. of the saturated hydrocarbon fractions of the Setap Shale and the Belait form.tions displayed m.nom.dal n-alkane distributions and nearly identical regular sterane com.ositions with a predom.nance of C27 regular *** are consistent with open m.rine depositional environm.nts dom.nated by m.rine biological *** related feature of these rock extracts is the presence of a high relative abundance of gam.acerane,indicating anoxic m.rine hypersaline source depositional *** relatively high abundance of com.on land plant-derived biom.rkers,such as bicadinanes and oleananes,is a clear indication of a m.jor terrigenous input to the source of the extractable organic *** predom.nance of oleanane biom.rkers in both form.tions is indicative of angiosperm.s input and Tertiary source *** high C29/C30 hopane ratios,m.derate developm.nt of C33-C35 hopanes,high abundance of tricyclic terpanes and a slight predom.nance of C27 regular sterane over C28 and C29 steranes are characteristic features tending to suggest a significant m.rine influence on these source rocks,thereby suggesting a m.xed source *** 22S/(22S+22R)C32 hopane ratio has reached equilibrium.and this is supported by the high m.turity level as indicated by the 22S/22SC31-33 extended hopane ratios and 20S/(20S+20R)C29 regular steranes ratios.

关键词：有机质成熟度沉积古环境黑色页岩地球化学方法沉积物评估马来西亚贝雷

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An organic geochem.cal investigation on organic rich sedim.nts from.two Neogene form.tions in the Klias Peninsula area,West Sabah,m.laysia

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Chinese Journal Of Geochem.stry 2009年第3期28卷 264-270页

作者： Am.r m. Burgan Che Aziz Ali School of Environm.ntal and Natural Resources Department of GeologyFaculty of Science and Technology Universiti Kebangsaan Malaysia43600 UKM BangiSelangor

Twenty organic rich outcrop sam.les from.the Belait and Setap Shale form.tions in the Klias Peninsula area, West Sabah, were analysed by m.ans of organic petrology and geochem.cal techniques. The aim. of this study are to assess the type of organic m.tter, therm.l m.turity and established source rock characterization based prim.rily on Rock-Eval pyrolysis data. The shales of the Setap Shale Form.tion have TOC values varying from.0.6 wt%–1.54 wt% with a m.an hydrogen index (HI) of 60.1 m./g, whereas the shales of the Belait Form.tion have TOC values ranging from.0.36 wt%–0.61 wt% with a m.an (HI) of 38.2 m./g, indicating that both form.tions have TOC>0.5 wt% the m.nim.m.lim.t for hydrocarbon generation. The sam.les do not contain sufficient hydrogen-rich organic m.tter (types I, II and III) to be considered good quality source rocks. The kerogen of type II is predom.nantly of m.rine origin. This organic m.tter was deposited in clastic algal environm.nts. Geochem.cal data (Rock-Eval, Tm.x values ranging from.377–451℃ for shales of the Setap Shale Form.tion and ranging from.466–498℃ for shales of the Belait Form.tion, typical of high m.turity), indicate variable m.turation histories in both form.tions. The m.turation level varied from.the beginning to the peak stage of oil generation in the Setap Shale Form.tion and it has reached the over-m.ture level in the sam.les of the Belait Form.tion.

关键词：半岛地区地球化学调查有机沉积物马来西亚有机质类型优质烃源岩热成熟度地球化学技术

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