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Geochem.stry and.geochronology of m.fic rocks from.the Spanish Central System.Constraints on the m.ntle evolution beneath central Spain

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Geoscience Frontiers 2020年第5期11卷 1651-1667页

作者： d.Orejana C.Villaseca m.Kristoffersen d.to.m.neralogia y Petrologia Facultad de Ciencias GeologicasUniversidad Complutense de Madrid28040MadridSpain Instituto d. Geociencias IGEO(UCm CSIC)28040MadridSpain d.partm.nt of Geosciences University of OsloP.O.Box 1047BlindernN-0316OsloNorway

The Spanish Central System.SCS)contains several suites of Palaeozoic m.fic igneous intrusions with contrasting geochem.cal affinity:Ord.vician tholeiitic m.tabasites,Variscan calc-alkaline gabbros(Gb1)and.m.crod.orites(Gb2),shoshonitic m.nzogabbros(Gb3)and.alkaline d.abases and.lam.rophyres(Gb4).Not all of these rocks are accurately d.ted.and.several aspects of their genesis are still poorly *** present new whole-rock geochem.cal d.ta(m.jor and.trace elem.nts,and.Sr-Nd.isotopes),U-Pb and.Lu-Hf isotopic ratios on m.gm.tic zircons and.40 Ar/39Ar am.hibole geochronology results in ord.r to establish a precise chronology for the successive events of m.gm.tism.in the SCS,and.d.scuss the nature of their m.ntle *** ages have been d.term.ned.for the Variscan gabbros(305-294 m.),the m.crod.orites(299 m.)and.the accom.anying felsic porphyries(292 m.),the shoshonitic m.nzogabbros(285 m.),and.the alkaline d.abases(274 m.)and.m.nzosyenites(271-264 m.).Accord.ng to this inform.tion,the Variscan m.fic m.gm.tism.would.be m.inly concentrated.in the range of 305-294 m.,with a final m.nifestation represented.by the m.nor shoshonitic *** alkaline m.gm.tism.proved.to be slightly old.r than previously thought and.yield.d.at least two d.stinct pulses:d.abases and.*** Hf isotopes evid.nce the involvem.nt of d.pleted.and.slightly enriched.m.ntle *** bulk of the eHf values are in the broad.range of-8 to+11,ind.cative of m.lting both d.pleted.and.enriched.m.ntle *** high within-sam.le Hf isotope variation(up to-11 epsilon units)shown by sam.les from.the Variscan series(gabbros,m.crod.orites and.m.nzogabbros)could.be explained.m.inly by hybrid.sation of m.gm.s d.rived.from.heterogeneous lithospheric m.ntle *** estim.tes ind.cate that the Variscan m.fic m.gm.s were extracted.from.the *** Nd.Hf isotopic com.osition of these suites of rocks suggests the recycling of pelitic sed.m.nts d.ring the Cad

关键词： Spanish central system m.fic m.gm.tism m.ntle sources Lu–Hf isotopes Hf–Nd.d.coupling m.tasom.tism

Convergent evolution of brain m.rphology and.com.unication m.d.lities in lizard.

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Current Zoology 2015年第2期61卷 281-291页

作者： Christopher d. ROBIN.SON m.chael S. PATTON Britm.y m. ANd.E m.chele A. JOHNSON Trinity University Department of Biology One Trinity Place San Antonio Texas 78212 USA

Anim.ls com.unicate inform.tion within their environm.nts via visual, chem.cal, aud.tory, and.or tactile m.d.lities. The use of each m.d.lityis generally linked.to particular brain regions, but it is not yet known whether the cellular m.rphology of neurons in these regions has evolved.in association with the relative use of a *** investigated.relationships between the behavioral use of com.unication m.d.lities and.neural m.rphologies in six lizard.species. Two of these species （Anolis carol# nensis and.Leiocephalus carinatus） prim.rily use visual signals to com.unicate with conspecifics and.d.tect potential prey, and.two （Aspid.scelis gularis and.Scincella lateralis） com.unicate and.forage prim.rily using chem.cal signals. Two other species （Hem.d.ctylus turcicus and.Sceloporus olivaceus） use both visual and.chem.cal signals. For each species, we perform.d.beha- vioral observations and.quantified.rates of visual and.chem.cal behaviors. We then cryosectioned.brain tissues from.9-10 m.les of each species and.m.asured.the som. size and.d.nsity of neurons in two brain regions associated.with visual behaviors （the lat- eral geniculate nucleus and.the nucleus rotund.s） and.one region associated.with chem.cal behaviors （the nucleus sphericus）. With analyses cond.cted.in a phylogenetic context, we found.that species that perform.d.higher rates of visual d.splays had.a d.nser lateral geniculate nucleus, and.species that used.a higher proportion of chem.cal d.splays had.larger som.s in the nucleus sphericus. These relationships suggest that neural m.rphologies in the brain have evolved.convergently in species with sim.lar com.unication behaviors .

关键词： Brain Com.unication m.d.lity Lizard. Pherom.nes Social behavior Vision

Toward. full repair of d.fects in red.ced.graphene oxid. film. by two-step graphitization

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Nano Research 2013年第3期6卷 216-233页

作者： Ruben Rozad. Juan I, Pared.s Silvia Villar-Rod.l Am.lia m.rlinez-Alonso Juan m. d. Tascon Instituto Nacional d.l Carbon INCAR-CSIC Apartado 73 33080 Oviedo Spain

The com.lete restoration of a perfect carbon lattice has been a central issue in the research on graphene d.rived.from.graphite oxid. since this preparation route was first proposed.several years ago, but such a goal has so far rem.ined.elusive. Here, we d.m.nstrate that the highly d.fective structure of red.ced.graphene oxid. sheets assem.led.into free-stand.ng, paper-like film. can be fully repaired.by m.ans of high tem.erature annealing （graphitization）. Characterization of the film. by X-ray photoelectron and.Ram.n spectroscopy, X-ray d.ffraction and.scanning tunneling m.croscopy ind.cated.that the m.in stages in the transform.tion of the film. were （i） com.lete rem.val of oxygen functional groups and.generation of atom.c vacancies （up to 1,500 ~C）, and.（ii） vacancy annihilation and.coalescence of ad.acent overlapping sheets to yield.continuous polycrystalline layers （1,800-2,700 ~C） sim.lar to those of highly oriented.graphites. The prevailing type of d.fect in the polycrystalline layers were the grain bound.ries separating neighboring d.m.ins, which were typically a few hund.ed.nanom.ters in lateral size, exhibited.long-range graphitic ord.r and.were virtually free of even atom.c-sized.d.fects. The electrical cond.ctivity of the annealed.film. was as high as 577,000 S-m.1, which is by far the largest value reported.to d.te for any m.terial d.rived.from.graphene oxid., and.strategies for further im.rovem.nt without the need.to resort to higher annealing tem.eratures are suggested. Overall, this work opens the prospect of truly achieving a com.lete restoration of the carbon lattice in graphene oxid. m.terials.

关键词： graphene graphene oxid. film. annealing d.fect

Efficient approaches of d.term.ning the m.tion of a spherical particle in a swirling fluid.flow using weighted.resid.al m.thod.

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Particuology 2015年第6期13卷 68-74页

作者： Seiyed.E. Ghasem. m. Vatani d.d. Ganji Young Researchers and.Elite Club Qaemshahr Branch Islamic Azad University Qaemshahr lran d.partm.nt of m.chanical Engineering Babol University of Technology Babol lran

The m.tion of a spherical particle released.in a swirling fluid.flow is stud.ed.em.loying the least-squares m.thod.and.m.thod.of m.m.nts. The governing equations are obtained.and.solved.em.loying the two m.thod.. The accuracy of the results is exam.ned.against the results of a fourth-ord.r Runge-Kutta num.r- ical m.thod. The effects of various param.ters, nam.ly the initial rad.us, initial rad.al velocity, initial angular velocity, and.d.ag-to-inertia ratio, on the non-d.m.nsional velocity profiles and.particle position d.stribution are consid.red. The results show that the rad.al velocity increases over tim. while the angular velocity d.creases, and.that an increase in the initial rad.al velocity increases the particle rad.al d.stance and.angular velocity but d.creases the rad.al velocity profile.

关键词： Spherical particle Swirling flow Rad.al velocity Angular velocity Least-squares m.thod m.thod.of m.m.nts

Spontaneous Ca2+ oscillations in subcellular com.artm.nts of vascular sm.oth m.scle cells rely on d.fferent Ca2+ pools

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Cell Research 2004年第5期14卷 379-388页

作者： Olesya d. FEd.RYAK,Yvonne SEARLS,Irina V. Sm.RNOVA,d.uglas m. BURNS,Lisa STEHNO-BITTEL d.partm.nts of Physical Therapy and.Rehabilitation Sciences University of Kansas m.d.cal Center Kansas City KS 66160 USA d.partm.nts of Physical Therapy and.Rehabilitation Sciences University of Kansas m.d.cal Center Kansas City KS 66160 USA d.partm.nt of Anatom. and.Cell Biology University of Kansas m.d.cal Center Kansas City KS 66160 USA d.partm.nts of Physical Therapy and.Rehabilitation Sciences University of Kansas m.d.cal Center Kansas City KS 66160 USA VA m.d.cal Center Kansas City m. 64128 USA d.partm.nts of Physical Therapy and.Rehabilitation Sciences University of Kansas m.d.cal Center Kansas City KS 66160 USA d.partm.nt of Anatom. and.Cell Biology University of Kansas m.d.cal Center Kansas City KS 66160 USA

Spontaneous Ca2+ oscillations in vascular sm.oth m.scle cells have been m.d.led.using a single Ca2+ pool. This report d.scribes spontaneous Ca2+ oscillations d.pend.nt on two separate Ca2+ sources for the nuclear versus cytoplas- m.c com.artm.nts. Changes in free intracellular Ca2+ were m.nitored.with ratiom.tric Ca2+- fluorophores using confo- cal m.croscopy. On average, spontaneous oscillations d.veloped.in 79% of rat aortic sm.oth m.scle cells that were synchronous between the cytoplasm.and.nucleus. Red.ction of extracellular Ca2+ (m. d.creased.the frequency and.am.litud. of the cytoplasm.c oscillations with 48% of the oscillations asynchronous between the nuclear and. cytoplasm.c com.artm.nts. Sim.lar results were obtained.with the Ca2+ channel blockers, nim.d.pine and.d.ltiazem. Arg-vasopressin (AVP) ind.ced.a rapid.release of intracellular Ca2+ stores that was greater in the nuclear com.artm.nt (4.20 ± 0.23 ratio units, n = 56) than cytoplasm.(2.54 ± 0.28) in cells that had.spontaneously d.veloped.prior oscillations. Conversely, cells in the sam. cond.tions lacking oscillations had.a greater AVP-ind.ced.Ca2+ transient in the cytoplasm. (4.99 ± 0.66, n = 17) than in the nucleus (2.67 ± 0.29). Pre-treatm.nt with Ca2+ channel blockers d.pressed.the AVP responses in both com.artm.nts with the cytoplasm.c Ca2+ m.st d.m.nished. d.pletion of internal Ca2+ stores prior to AVP exposure blunted.the nuclear response, m.m.cking the response of cells that lacked.prior oscillations. Spontaneous oscillating cells had.a greater sarcoplasm.c reticulum.network than cells that d.d.not oscillate. We propose that sponta- neous nuclear oscillations rely on perinuclear sarcoplasm.c reticulum.stores, while the cytoplasm.c oscillations rely on Ca2+ influx.

关键词： oscillations vascular sm.oth m.scle cells nuclear Ca2+ vasopressin thapsigargin d.ltiazem nim.d.pine.

Scanning m.crofocus Sm.ll Angle X-ray Scattering Stud. of the Avian Eggshell

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Journal of Bionic Engineering 2006年第1期3卷 11-18页

作者： d. Lam.ie m. m. Bain S. E. Solom.n T. J. Wess d.vision of Cell Sciences Institute of Comparative Medicine Faculty of Veterinary Medicine University of Glasgow Glasgow G61 1QH UK Biophysics Group School of Optometry and Vision Sciences Redwood Building King Edward VII Avenue Cardiff University Cardiff CF10 3NB UK d.vision of Cell Sciences Institute of Comparative Medicine Faculty of Veterinary Medicine University of Glasgow Glasgow G61 1QH UK

Synchrotron m.crofocus sm.ll angle X-ray scattering was used.to investigate the nanostructure and.m.croscopic variation of eggshells. It uses a m.crobeam.allowing the ability to probe interactions between the organic and.inorganic com.onents at nanom.ter level and.is id.al for m.pping over sm.ll areas to obtain a d.tailed.analysis of structural variations. Thin sections of eggshells were scanned.from.the shell m.m.rane （inner） to the cuticle （outer） surface. The d.ta collected.was used.to prod.ce two-d.m.nsional m.ps showing m.croscopic changes within the d.fferent layers of the eggshell. The structural alterations ap- parently could.have im.lications at the m.croscopic level of the resulting eggshell. As the organic m.trix is em.ed.ed.within the eggshell this m.y contribute to the variations observed.in calcite crystal form.and.texture, Structural inform.tion obtained.about a biom.terial at d.fferent length scales is im.ortant in relating the structure to its functional properties. This knowled.e and.the principles behind.the form.tion of biom.terials could.be used.in the attem.t of bioengineering new system..

关键词： biom.terial eggshell nanostructure m.crofocus sm.ll angle X-ray scattering

d.struction of hexafluoroethane in a d.electric-packed.bed.plasm. reactor

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Journal of Zhejiang University-Science A(Applied.Physics & Engineering) 2010年第7期11卷 538-544页

作者： d. H. KIm.Y. S. m.K S. B. LEE S. m. SHIN d.partm.nt of Chem.cal & Biological Engineering Research Institute of Advanced Technology Jeju National University Environm.ntal Business Unit Samsung Engineering Co. Ltd. Hwasung Gyeonggido Korea

The d.struction of hexafluoroethane (C2F6), also known as R-116, was investigated.in a nontherm.l plasm. reactor packed.with d.electric pellets. The effects of the feed.gas com.osition and.the input power on the d.struction of C2F6 were exam.ned. The feed.gas com.osition was varied.by changing the oxygen content, the argon content and.the initial C2F6 concentration. An increased.input power led.to increased.C2F6 d.struction as a result of prom.ting the electron-m.lecule collisions to d.ssociate C2F6 m.lecules. The ad.ition of argon to the feed.gas greatly im.roved.the C2F6 d.struction by red.cing the energy losses d.e to vibrational excitation and.d.ssociation of N2 m.lecules, while the increases in the oxygen content and.the initial C2F6 concentration d.creased.the d.struction efficiency. The byprod.cts includ.ng CO2, CO, COF2, CF4, SiF4, NO2, and.N2O were id.ntified. and.the d.struction m.chanism. were elucid.ted. referring to these com.ound.. The m.st abund.nt byprod.ct was found.to be carbonyl fluorid. (COF2), ind.cating that it serves as an im.ortant m.d.um.to convert C2F6 into CO2. The energy requirem.nt for the C2F6 d.struction was in the range of 8.2–45.3 m./g, d.pend.ng on the initial concentration.

关键词： Hexafluoroethane (C2F6) Nontherm.l plasm. Gas com.osition d.struction m.chanism.

Glia-to-neuron reprogram.ing to the rescue?

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Neural Regeneration Research 2025年第5期20卷 1395-1396页

作者： Jack W.Hickm.tt Cind. m.m.rshead d.partm.nt of Surgery University of TorontoTorontoONCanada d.nnelly Centre for Cellular and.Biom.lecular Research TorontoONCanada Institute of Biom.d.cal Engineering University of TorontoTorontoONCanada The KITE Research Institute Toronto Rehabilitation InstituteUniversity Health NetworkTorontoONCanada

Over the last two d.cad.s,the d.gm. that cell fate is im.utable has been increasingly challenged.with im.ortant im.lications for regenerative *** brea kth rough d.scovery that ind.ced.pluripotent stem.cells could.be generated.from.ad.lt m.use fibroblasts is powerful proof that cell fate can be *** exciting extension of the d.scovery of cell fate im.erm.nence is the d.rect cellular reprogram.m.ng hypothesis-that term.nally d.fferentiated.cells can be reprogram.ed.into other ad.lt cell fates without first passing through a stem.cell state.

关键词： program.ing passing proof

Extragastric m.nifestations of Helicobacter pylori infection: Possible role of bacterium.in liver and.pancreas d.seases

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World.Journal of Hepatology 2015年第30期7卷 2968-2979页

作者： Elizabeth m. rabelo-Goncalves Bruna m.Roesler Jose m. Zeitune Laboratory of Gastroenterology and.Hepatology Center of Diagnosis of Digestive DiseasesState University of CampinasCampinasSao Paulo 13083-878Brazil d.partm.nt of Internal m.d.cine Faculty of Medical SciencesState University of CampinasCampinasSao Paulo13083-887Brazil

Helicobacter pylori(H. pylori) is an ancient m.croorganism.that has co-evolved.with hum.ns for over 60000 years. This bacterium.typically colonizes the hum.n stom.ch and.it is currently recognized.as the m.st com.on infectious pathogen of the gastrod.od.nal tract. Although its chronic infection is associated.with gastritis, peptic ulcer, d.splasia, neoplasia, m.LT lym.hom. and.gastric ad.nocarcinom., it has been suggested.the possible association of H. pylori infection with several extragastric effects includ.ng hepatobiliary and.pancreatic d.seases. Since a m.croorganism.resem.ling H. pylori was d.tected.in sam.les from.patients with hepatobiliary d.sord.rs, several reports have been d.scussed.the possible role of bacteria in hepatic d.seases as hepatocellular carcinom., cirrhosis and.hepatic encephalopathy, nonalcoholic fatty liver d.sease and.fibrosis. Ad.itionally, stud.es have reported.the possible association between H. pylori infection and.pancreatic d.seases, especially because it has been suggested.that this infection could.change the pancreatic physiology. Som. of them.have related.a possible association between the m.croorganism.and.pancreatic cancer. H. pylori infection has also been suggested.to play a role in the acute and.chronic pancreatitis pathogenesis, autoim.une pancreatitis, d.abetes m.llitus and.m.tabolic synd.om.. Consid.ring that association of H. pylori to liver and.pancreas d.seases need. further clarification, our work offers a review about the results of som. investigations related.to the potential pathogenicity of H. pylori in these extragastric d.seases.

关键词： Hepatocellular carcinom. Cirrhosis Hepaticencephalopathy Helicobacter pylori Nonalcoholic fattyliver d.sease Fibrosis Pancreatitis Pancreatic cancer d.abetes m.llitus m.tabolic synd.om.