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Time series analysis of mantle cycles Part Ⅱ:The geologic record in zircons, large igneous provinces and mantle lithosphere

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Geoscience Frontiers 2019年第4期10卷 1327-1336页

作者： Kent C. Condie Stephen j. Puetz Department of Earth & Environmental Science New Mexico Institute of Mining and TechnologySocorroNM87801USA Progressive Science Institute HonoluluHI96815USA

Igneous and detrital zircons have six major U/Pb isotopic age peaks in common(2700 Ma,1875 Ma.1045 Ma,625 Ma,265 Ma and 90 Ma).For igneous rocks,each age peak is comprised of subpeaks with distinct geographic distributions and a subpeak age range per age peak≤100 *** are eight major LIP age peaks(found on≥10 crustal provinces)of which only four are in common to major detrital zircon age peaks(2715 Ma,1875 Ma,825 Ma,90 Ma).Of the whole-rock Re depletion ages,58%have correspo nding detrital zircon age peaks and 55%have corresponding LIP age *** age pea ks are fou nd in common to igneous zircon,detrital zircon,LIP,and Re depletion age time series(3225 Ma,2875 Ma,2145 Ma,2085 Ma,1985 Ma,1785 Ma,1455 Ma,1175 Ma,825 Ma,and 90 Ma).and these are very robust peaks on a global scale as recorded in both crustal and mantle *** 50%of the age peaks in each of these time series correspond to predicted peaks in a 94-Myr mantle cycle,including four of the ten peaks in common to all four time series(2875 Ma,1785 Ma,825 Ma and 90 Ma).Age peak widths and subpeak ranges per age peak suggest that mantle events responsible for age peaks are2500 Ma),with the number of new provinces in which age peaks are represented decreasing with time within each *** breaks between the populations(at 2.5 Ga and 1 Ga)fall near the onsets of two transitions in Earth *** First Transition may represent a change from stagnant-lid tectonics into plate tectonics and the Second Transition,the onset of subduction of continental *** major factor controlling geographic distribution of age peaks is the changing locations of ***^2 Ga,age subpeaks and peaks are housed in orogens within or around the edges of crustal provinces,mostly in accretionary *** beginning at 1.9 Ga,collisional orogens become more *** coincidence in duration

关键词： Isotopic age peaks U/Pb zircon ages Re depletion ages Large igneous provinces Age peak correlation Mantle cycles

SARS-CoV-2 productively infects primary human immune system cells in vitro and in CoviD-19 patients

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journal of Molecular Cell Biology 2022年第4期14卷 51-64页

作者： Marjorie C.Pontelli italo A.Castro Ronaldo B.Martins Leonardo La Serra Flavio P.Veras Daniele C.Nascimento Camila M.Silva Ricardo S.Cardoso Roberta Rosales Rogério Gomes Thais M.Lima juliano P.Souza Brenda C.Vitti Diego B.Caetite Mikhael H.F.de Lima spencer D.Stumpf Cassandra E.Thompson Louis-Marie Bloyet juliana E Toller-Kawahisa Marcela C.Giannini Leticia P.Bonjorno Marial.F.Lopes Sabrina S.Batah Li Siyuan Rodrigo Luppino-Assad Sergio C.L.Almeida Fabiola R.Oliveira Maira N.Benatti Lorena L.F.Pontes Rodrigo C.Santana Fernando C.Vilar Maria Auxiliadora-Martins Pei-Yong Shi Thiago M.Cunha Rodrigo T.Calado joséC.Alves-Filho Dario S.Zamboni Alexandre T.Fabro Paulo Louzada-junior Rene D.R.Oliveira Sean P.j.Whelan Fernando Q.Cunha Eurico Arruda Virology Research Center Ribeirao Preto Medical SchoolUniversity of Sao Pauloibeirao PretoSao Paulo 14049-900.Brazil Center of Research in Inflammatory Diseases Ribeirao Preto Medical SchoolUniversity of Sao PauloRibeirao PretoSao Paulo 14049-900Brazil Department of Celland Molecular Biology Ribeirao Preto Medical SchoolUniversityof Sao PauloRibeirao PretoSao Paulo 14049-900 Brazil Regional Blood Centerof Ribeirao Preto Ribeirao Preto Medical ScholUniversity of Sao PauloRibeirao PretoSao Paulo 14049-900Brazil Department of Biochemistry&Molecular Biology the University of Texas Medical BranchGalvestonTX7755USA Divisions of Clinical lmmunology Infectious Diseases and Intensive Care UnitRibeirao Preto Medical Schooniversity of Sao PauloRibeirao PretoSao Paulo 14049-900Brazil Department of Pathology Ribeirao Preto Medical Scholniversity of Sao PauloRibeirao PretoSao Paulo 14049-900Brazil Department of Molecular Microbiology.Washington University in St.Louis Saint LouisMO 63110USA

The severe acute respiratory syndrome coronavirus 2(SARS-CovV-2)infection is associated with a hyperinflammatory state and lymphocytopenia,a hallmark that appears as both signature and prognosis of disease severity *** cytokine storm and a sustained inflammatory state are commonly associated with immune cell depletion,it is still unclear whether direct SARS-Cov-2 infection of immune cells could also play a role in this scenario by harboring viral *** found that monocytes,as well as both B and T lymphocytes,were susceptible to SARS-Cov-2 infection in vitro,accumulating double-stranded RNA consistent with viral RNA replication and ultimately leading to expressive T cell *** addition,flow cytometry and immunofluorescence analysis revealed that SARS-Cov-2 was frequently detected in monocytes and B lymphocytes from coronavirus disease 2019(CoVID-19)*** rates of SARS-Cov-2-infected monocytes in peripheral blood mononuclear cells from CoVID-19 patients increased over time from symptom onset,with SARS-CoV-2-positive monocytes,B cells,and CD4+T lymphocytes also detected in postmortem lung *** results indicated that SARS-CoV-2 infection of blood-circulating leukocytes in covID-19 patients might have important implications for disease pathogenesis and progression,immune dysfunction,and virus spread within the host.

关键词： SARS-CoV-2 CoVID-19 lymphocytopenia peripheral blood mononuclear cell(PBMC) lymphocytes monocytes apoptosis

Identification, Cloning and Characterization of Dictyoglomus Turgidum CelA, an Endoglucanase with Cellulase and Mannanase Activity

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journal of Life Sciences 2011年第7期5卷 488-496页

作者： Phillip j. Brumm spencer Hermanson joshua Luedtke David A. Mead C5-6 Technologies 2120 W. Greenview Drive Middleton W153562 USA

The discovery of new, highly active, biomass-degrading enzymes is important to the development of a sustainable biofuels industry. Dictyoglomus turgidum, a thermophilic, anaerobic eubacterium that ferments cellulose and produces ethanol and hydrogen, was chosen as a candidate to screen for novel enzymes. A novel thermostable endoglucanase, CelA, was identified and purified during screening of a shotgun library of Dictyoglomus turgidum and subsequently subcloned and expressed in E. coli. The celA gene coding for a 312 amino acid protein showed low homology to proteins outside the genus Dictoglomi and lacked an apparent signal peptide. CelA had a broad substrate range, possessing both endo and exo activity on soluble and insoluble β-(1,4)-linked glucose-containing substrates as well as endo activity on soluble and insoluble β-(1,4)-linked mannose containing substrates. The specific activity of CelA was 226 U/mg using β-glucan, 66 U/mg using glucomannan, and 63 U/mg using CMC as substrates. The high temperature optimum of 70 ℃ to 80 ℃ and wide substrate range of the enzyme might make it an excellent tool for biomass degradation at high temperature.

关键词：内切葡聚糖酶纤维素酶亚克隆甘露聚糖酶鉴定大肠杆菌生物燃料厌氧发酵

薄弱的造山带岩石圈地幔影响地幔柱触发的超大陆裂解模式

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矿物岩石地球化学通报 2021年第1期40卷 137-137页

作者： Dang Z Zhang N Li Z X Huang C spencer C j Liu Y B 袁超(编译) 不详

超大陆的裂解是全球构造演化的基本过程,同时也是超大陆旋回的重要组成部分。目前对于超大陆裂解的研究主要集中在是否是由于俯冲或是地幔柱作用而导致超大陆的裂解,但对于其他关键因素,如对控制大陆裂解轨迹的非刚性特性并没有得到充... 详细信息

超大陆的裂解是全球构造演化的基本过程,同时也是超大陆旋回的重要组成部分。目前对于超大陆裂解的研究主要集中在是否是由于俯冲或是地幔柱作用而导致超大陆的裂解,但对于其他关键因素,如对控制大陆裂解轨迹的非刚性特性并没有得到充分研究。最近,北京大学的Zhang Z及其合作者基于具有完整重建历史的潘吉亚超大陆的裂解,根据全球的造山带位置和几何特征,通过三维地球动力学模拟以及地质记录对比解译了超大陆裂解的控制因素和过程。

关键词：动力学模拟非刚性地质记录造山带合作者几何特征地幔柱

Investigations of Microwave Pulse Shortening in a High Power Coaxial Gyrotron

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Investigations of Microwave Pulse Shortening in a High Power...

Improved slope safety analysis by new Druker-Prager type criterion

2000 25～(th) International Conference on Infrared and Millimeter Waves Conference Digest

＜正＞ Experiments have been performed on a coaxial gyrotron driven by the Michigan Electron Long BeamAccelerator（MELBA）at parameters:V=-0.8 MV,I=1-10 kA,and pulseiength=*** pulse shortening has been investigated by spectroscopic plasmadiagnostics to characterize plasma effects inside the operating ***-frequency plasmaprocessing has been applied to clean the inside of the gyrotron in order to reduce the deleteriouseffects of plasma on the microwave pulselength and *** show that plasma cleaning canextend the microwave pulselength and increase the integrated microwave energy output by 15-245% in this gyrotron.

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journal of Central South University 2012年第4期19卷 1132-1137页

作者：朱俊高彭凯 j.F.Shao 刘汉龙 Key Laboratory of Geo-mechanics and Embankment Engineering of Ministry of Education Hohai University Geotechnical Research Institute Hohai University Laboratoire de Mécanique de Lille UMR CNRS 8107Equipe Mécanique des Géomatériaux CohérentsPolytech'LilleCité Scientifique59655 Villeneuve d'AscqFrance

Based on Mohr-Coulomb(M-C) criterion,the parameters of Druker-Prager(D-P) criterion for geomaterial were determined under non-associated flow rule,and thus a new D-P type criterion was *** assumptions were employed during the derivation:1) principal strains by M-C model and D-P model are equal,and 2) the material is under plane strain *** on the analysis of the surface on π plane,it is found that the proposed D-P type criterion is better than the D-P criterion with M-C circumscribed circle or M-C inscribed circle,and is applicable for stress Lode angle less than *** comparing the predicted results with the test data of sand under plane strain condition and other D-P criteria,the proposed criterion is verified and agrees well with the test data,which is further proved to be better than other D-P type criteria in certain range of Lode *** criterion was compiled into a finite difference package FLAC3D by user-subroutine,and was used to analyze the stability of a slope by strength reduction *** predicted slope safety factor from the proposed criterion agrees well with that by spencer method,and it is more accurate than that from classic D-P criteria.

关键词：标准砂安全性分析非关联流动法则应力洛德角格型平面应变边坡稳定三维弹塑性

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非固结砂与砂岩中的岩石骨架模量

油气藏评价与开发 1995年第3期 84-84页

作者： j.W.spencer

本文研究了非固结砂和固结砂岩中的空白颗粒骨架(骨架系数)的弹性模量。该研究的目的是提高地震振幅异常解释及与油气藏有关的AVO异常解释的质量。我们用实验室仪器测量了地震频带(0.2～155Hz范围内)11厘米长的非固结砂样品的骨架泊松... 详细信息

本文研究了非固结砂和固结砂岩中的空白颗粒骨架(骨架系数)的弹性模量。该研究的目的是提高地震振幅异常解释及与油气藏有关的AVO异常解释的质量。我们用实验室仪器测量了地震频带(0.2～155Hz范围内)11厘米长的非固结砂样品的骨架泊松比和杨氏模量。我们用超声脉冲速度测量法测量了固结砂岩的骨架

关键词：砂岩碎屑岩骨架模测井分析测井解释固结模量

Corrections to the scaling of the second-order structure function in isotropic turbulence

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Acta Mechanica Sinica 2010年第2期26卷 151-157页

作者： Le Fang Wouter j. T. Bos Xiaozhou Zhou Liang Shao jean-Pierre Bertoglio Laboratoire de Mecanique des Fluides et d'Acoustique Universit6 de Lyon Ecole centrale de Lyon 69134 Ecully France Department of Mechanical Engineering Center for Biomedical Engineering Research University of Delaware 126 Spencer Laboratory Newark DE 19716 USA

The approach of Obukhov assuming a constant skewness was used to obtain analytical corrections to the scaling of the second order structure function, starting from Kolmogorov＇s 4/5 law. These corrections can be used in model applications in which explicit expressions, rather than numerical solutions are needed. The comparison with an interpolation formula proposed by Batchelor, showed that the latter gives surprisingly precise results. The modification of the same method to obtain analytical corrections to the scaling law, taking into account the possible corrections induced by intermittency, is also proposed.

关键词： Scaling law · Structure function ·Isotropic turbulence

Prevalence of intestinal schistosomiasis in pre-school aged children: a pilot survey in Marolambo District, Madagascar

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Infectious Diseases of Poverty 2021年第3期10卷 124-124页

作者： Caitlin Sheehy Heather Lawson Emmanuel H.Andriamasy Hannah j.Russell Alice Reid Gina U.Raderalazasoa Graham Dodge Robbie Kornitschky james M.StjPenney Tahiry N.Ranaivoson Antsa Andria niaina jenny S.Emmanoela Amaya L.Bustinduy jRussell Stothard Louis Andrianjaka Stephen A.spencer The University of Man Chester Medical School University of Man ChesterManchester M139NTUK 不详

School-aged children(SAC)have a considerable burden of intestinal schistosomiasis in Madagascar yet its burden in pre-school aged children(PSAC)is currently *** assess the at-risk status of PSAC,we undertook a pilot epidemiological survey in june 2019 examining children(n=89),aged 2-4-years of balanced gender,in six remote villages in Marolambo District,*** included use of urine-circulating cathodic antigen(CCA)dipsticks and coproscopy of stool with duplicate Kato-Katz(K-K)thick smears.

关键词： Schistosoma mansoni Soil-transmitted helminthiasis Paediatric Praziquantel Mass drug administration