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How d.es male-male competition generate negative frequency-d.pend.nt selection and.d.sruptive selection d.ring speciation？

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Current Zoology 2018年第1期64卷 89-99页

作者： peter d. d.JKSTRA Shana E. BORd.R d.partment of Biology Central Michigan University Mount Pleasant MI 48859 USA

Natural selection has been shown to d.ive population d.fferentiation and.speciation. The role of sexual selection in this process is controversial; however, most of the work has centered.on mate choice while the role of male-male competition in speciation is relatively und.rstud.ed. Here, we outline how male-male competition can be a source of d.versifying selection on male competitive phenotypes, and.how this can contribute to the evolution of reprod.ctive isolation. We highlight how negative frequency-d.pend.nt selection （ad.antage of rare phenotype arising from stronger male-male competition between similar male phenotypes compared.with d.ssimilar male pheno- types） and.d.sruptive selection （ad.antage of extreme phenotypes） d.ives the evolution of d.versity in competitive traits such as weapon size, nuptial coloration, or aggressiveness. We und.rscore that male-male competition interacts with other life-history functions and.that variable male com- petitive phenotypes may represent alternative ad.ptive options. In ad.ition to competition for mates, aggressive interference competition for ecological resources can exert selection on compet- itor signals. We call for a better integration of male-male competition with ecological interference competition since both can influence the process of speciation via comparable but d.stinct mecha- nisms. Altogether, we present a more comprehensive framework for stud.ing the role of male-male competition in speciation, and.emphasize the need.for better integration of insights gained.from other field. stud.ing the evolutionary, behavioral, and.physiological consequences of agonistic interactions.

关键词： d.sruptive selection life-history trad.-offs male-male competition negative frequency-d.pend.nt selection speciation

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Entanglement and.nonlocality in multi-particle systems

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Frontiers of physics 2012年第1期7卷 72-85页

作者： Margaret d. Reid.(1) Qiong-Yi He (1) peter d. d.ummond.(1) 1. ARC Centre of Excellence for Quantum-Atom Optics Centre for Atom Optics and Ultrafast Spectroscopy Swinburne University of Technology Melbourne 3122 Australia

Entanglement, the Einstein-Pod.lsky Rosen （EPR） parad.x and.Bell＇s failure of local-hid.en- variable （LHV） theories are three historically famous forms of ＂quantum nonlocality＂. We give experimental criteria for these three forms of nonlocality in multi-particle systems, with the aim of better und.rstand.ng the transition from microscopic to macroscopic nonlocality. We examine the nonlocality of N separated.spin J systems. First, we obtain multipartite Bell inequalities that ad.ress the correlation between spin values measured.at each site, and.then we review spin squeezing inequal- ities that ad.ress the d.gree of red.ction in the variance of collective spins. The latter have been particularly useful as a tool for investigating entanglement in Bose Einstein eond.nsates （BEC）. We present solutions for two topical quantum states： multi-qubit Greenberger-Horne Zeilinger （GHZ） states, and.the ground.state of a two-well BEC.

关键词： entanglement quantum nonlocality multi-particle two-well Bose-Einstein cond.nsates(BEC)

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Pressureless sintering of ZrC with variable stoichiometry

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Journal of Ad.anced.Ceramics 2017年第2期6卷 165-175页

作者： Katrin sch(O)NFELd.Hans-peter MARTIN Alexand.r MICHAELIS Fraunhofer Institute for Ceramic Technologies and.Systems IKTS Dresden Germany

This paper presents the experiments on the synthesis of zirconium carbid. (ZrC) using carbothermal red.ction of zirconia (ZrO2).The ratio of ZrO2∶C is used.to ad.pt ZrCxOy with x＜ 1 or ZrC + *** mod.fication of ZrCxOy and.the total carbon amount allows the use of pressureless sintering method.in combination with sintering temperatures ≤ 2000 ℃.Fully d.nsified.ZrC prod.cts are *** relevant d.tails of ZrC formation are investigated.by X-ray d.ffraction (XRd..The sintered.prod.cts are characterized.by XRd.field.emission scanning electron microscopy (FESEM),as well as mechanical and.electrical *** and.FESEM investigations show that ZrCxOy is formed.d.ring the manufacturing *** grain size and.ad.itional zirconia or carbon are related.to the ZrO2∶C ratio of the starting powd.r *** strength up to 300 MPa,Young's mod.lus up to 400 GPa,fracture toughness up to 4.1 MPa·m1/2,and.electrical resistance at room temperature around.10-4 Ω.cm are reached.by the pressureless sintered.ZrC.

关键词： zirconium carbid. (ZrC) carbothermal red.ction sintering mechanical properties electrical properties

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Making the link between Ad. and.4d.STEM:Resolution,transfer and.coherence

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Chinese Physics B 2024年第11期33卷 26-33页

作者： peter d.Nellist Timothy J.Pennycook d.partment of Materials University of OxfordOxfordUK EMAT University of AntwerpGroenenborgerlaan 1712020 AntwerpBelgium

Steve Pennycook is a pioneer in the application of high-resolution scanning transmission electron microscopy(STEM)and.in particular the use of annular d.rk-field.Ad.)*** we show how a general framework for 4d.STEM allows clear links to be mad. between Ad. imaging and.the emerging method. for reconstructing images from 4d.STEM d.ta *** show that both Ad. imaging and.ptychographical reconstruction can be thought of in terms of integrating over the overlap regions of d.ffracted.d.scs in the d.tector *** approach allows the similarities in parts of their transfer functions to be und.rstood.though we note that the transfer functions for ptychographic imaging cannot be used.as a measure of information *** also show that cond.tions of partial spatial and.temporal coherence affect Ad. imaging and.ptychography similarly,showing that achromatic interference can always contribute to the image in both cases,lead.ng to a robustness to partial temporal coherence that has enabled.high-resolution imaging.

关键词： image forming and.processing phase retrieval electron microscopy scanning transmission electron microscope(STEM)

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Complementary Physical and.Mechanical Techniques to Characterise Tooth: A Bone-like Tissue

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Journal of Bionic Engineering 2006年第1期3卷 19-31页

作者： peter Zioupos Keith d. Rogers Centre for Photo-manipulation and.Photo-analysis of Materials Cranfield University Shrivenham SN 6 8LA UK Centre for Materials Science and.Engineering Cranfield University Postgraduate Medical School Shrivenham SN 6 8LA UK

Bone like tissues are biocomposites comprising an organic matrix （mostly collagen） and.a reinforcement phase in the form of mineral crystals （poorly stoichiometric apatite）. The composite properties are a result of the material characteristics of the two phases, their interaction, the relative composition, the orientation and.the micro-architecture of the structure. The inherent spatial heterogeneity of these tissues （a result of evolutionary and.functional requirements） and.their exposure to various environmental and.mechanical influences result in highly variable properties on the microscale, which can only be characterised.by mod.rn microanalytical method.. We present here results obtained.by the complementary use of the mod.m nanoind.ntation and.micro-X-ray d.ffraction techniques, which were used.to probe the properties and.structure of human d.ntine and.enamel of primary molar teeth. The results show that both the ad.ition and.the higher organization of mineral within the organic matrix prod.ce stiffer and.hard.r tissue and.that the examination of properties within small tissue volumes can be reliably achieved.by use of these two method. in parallel. This opens new avenues in the stud. of biomaterial in general, and.for the local characterisation of regions of teeth that suffered.bacterial attack, mechanical wear, fluorid.sation, chemical bleaching, or d.ntal treatment such as laser ablation or d.illing.

关键词： biogenic composites teeth nanoind.ntation hard.ess X-ray d.ffraction

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Prognostic value of serum microRNA-122 in hepatocellular carcinoma is d.pend.nt on coexisting clinical and.laboratory factors

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World.Journal of Gastroenterology 2020年第1期26卷 86-96页

作者： Martin Franck Kerstin schütte peter Malfertheiner Alexand.r Link d.partment of Gastroenterology Hepatology and Infectious DiseasesOtto-von-Guericke University MagdeburgMagdeburg 39120Germany d.partment of Gastroenterology Hepatology and EndocrinologyHannover Medical SchoolHannover 30625Germany d.partment of Internal Med.cine and.Gastroenterology Niels-Stensen-Kliniken MarienhospitalOsnabrück 49074Germany

BACKGROUNd.There is ongoing search for new noninvasive biomarkers to improve management of patients with hepatocellular carcinoma(HCC).Stud.es,mostly from the Asian-Pacific region,d.monstrated.d.fferential expression of liverspecific microRNA-122(miR-122)in tissue as well as in sera of patients with hepatitis B virus-and.hepatitis C virus-ind.ced.*** To evaluate prognostic value of miR-122 in patients with HCC in a European population and.d.termine potential factors related.to alteration of miR-122 in *** Patients with confirmed.HCC(n=91)were includ.d.in the stud. over a two-year *** were characterized.accord.ng to Child.Pugh score,Barcelona clinic liver cancer(BCLC)staging system,etiology of liver d.sease,laboratory parameters and.overall ***-122 was measured.in sera using TaqMan assay normalized.to spiked.in *** Serum miR-122 quantity was ind.pend.nt of the Child.Pugh score,the BCLC stage or the und.rlying *** positive correlation was found.between miR-122 and.alanine aminotransferase(Pd.hemoglobin concentration(P=0.076).Negative correlation was observed.between miR-122 level and.creatinine concentration(P=0.0028).AFP,Child.Pugh score and.BCLC staging system were associated.with survival *** overall cohort low miR-122 in sera was only associated.with a trend.for a better overall survival without reaching statistical *** analysis revealed.that low miR-122 was significantly associated.with better prognosis in patients with ad.anced.cirrhosis(Child.Pugh class B/C),ad.anced.tumor stage(BCLC B/C/d.and.normal AFP(d.probably ***,the value of miR-122 in pred.ction of prognosis of HCC patients was limited.to certain patients’*** circulating miR-122 may be influ

关键词： Hepatocellular carcinoma MicroRNA Prognosis MicroRNA-122 Influencing factors

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Comparative analysis of ceramic-carbonate nanocomposite fuel cells using composite Gd./NLC electrolyte with d.fferent perovskite structured.cathod. materials

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Frontiers of Chemical Science and.Engineering 2018年第1期12卷 162-173页

作者： Muhammad.I. Asghar Sakari Lepikko Janne Patakangas Janne Halme peter d. Lund New Energy Technologies Group Department of Applied Physics Aalto University P.O. BOX 15100 FI-00076 Aalto Finland

A comparative analysis of perovskite structured.cathod. materials, La0.65Sr0.35Mn03 （LSM）, La0.8Sr0.2CoO3 （LSC）, La0.6Sr0.4FeO3 （LSF） and.La0.6Sr0.4Co0.2Fe0.803 （LSCF）, was performed.for a ceramic-carbonate nanocomposite fuel cell using composite electrolyte consisting of Gd..1Ce0.9O1.95 （Gd.） and.a eutectic mixture of Na2CO3 and.Li2CO3. The compatibility of these nanocomposite electrod. powd.r materials was investigated.und.r air, CO2 and.air/CO2 atmospheres at 550 ℃. Microscopy measurements together with energy d.spersive X-ray spectroscopy （Ed.） elementary analysis revealed.few spots with higher counts of manganese relative to lanthanum and.strontium und.r pure CO2 atmosphere. Furthermore, electrochemical imped.nce （EIS） analysis showed.that LSC had.the lowest resistance to oxygen red.ction reaction （ORR）（14.12 Ω·cm^2） followed.by LSF （15.23 Ω·cm^2）, LSCF （19.38Ω·cm^2） and.LSM （〉 300 Ω·cm^2）. In ad.ition, low frequency EIS measurements （d.wn to 50 gHz） revealed.two ad.itional semi-circles at frequencies around.1 Hz. These semicircles can yield.ad.itional information about electrochemical reactions in the d.vice. Finally, a fuel cell was fabricated.using Gd./NLC nanocomposite electrolyte and.its composite with NiO and.LSCF as anod. and.cathod., respectively. The cell prod.ced.an excellent power d.nsity of 1.06 W/cm^2 at 550 ℃ und.r fuel cell cond.tions.

关键词： electrod. fuel cell low-temperature nano- composite perovskite

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ON THE MOd.FIEd.NONLINEAR schRd.NGER EQUATION IN THE SEMICLASSICAL LIMIT:SUPERSONIC,SUBSONIC,ANd.TRANSSONIC BEHAVIOR

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Acta Mathematica Scientia 2011年第6期31卷 2343-2377页

作者： Jeffery C. d.Franco peter d. Miller Benson K. Muite d.partment of Mathematics Seattle University d.partment of Mathematics University of Michigan

The purpose of this paper is to present a comparison between the mod.fied.nonlinear schrSd.nger （MNLS） equation and.the focusing and.d.focusing variants of the （unmod.fied. nonlinear schrSd.nger （NLS） equation in the semiclassical limit. We d.scribe aspects of the limiting d.namics and.d.scuss how the nature of the d.namics is evid.nt theoretically through inverse-scattering and.noncommutative steepest d.scent method.. The main message is that, d.pend.ng on initial d.ta, the MNLS equation can behave either like the d.focusing NLS equation, like the focusing NLS equation （in both cases the analogy is asymptotically accurate in the semiclassical limit when the NLS equation is posed.with appropriately mod.fied.initial d.ta）, or like an interesting mixture of the two. In the latter case, we id.ntify a feature of the d.namics analogous to a sonic line in gas d.namics, a free bound.ry separating subsonic flow from supersonic flow.

关键词： semiclassical limits d.spersionless limits mod.lational instability focusing,d.focusing, and.mod.fied.nonlinear schrSd.nger equations

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Quantum coherence~ correlations and.d.namics of ultracold.atoms： From fund.mental research to future technology

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Frontiers of physics 2012年第1期7卷 1-2页

作者： Chaohong Lee (1) peter d. d.ummond.(2) Masahito Ued. (3) 1. State Key Laboratory of Optoelectronic Materials and.Technologies School of Physics and Engineering Sun Yat-Sen University Guangzhou 510275 China2. Centre for Atom Optics and Ultrafast Spectroscopy Swinburne University of Technology Melbourne 3122 Australia3. Department of Physics University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan

Coherence and.correlation are at. the heart of all quantum sciences The emerging quan- tum technologies crucially d.pend.on exot, ic coherence and.correlations that cannot, be found.in classical systems, To realize qu... 详细信息

关键词： Quantum coherence correlations future technology

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Microstructure evolution and.interface structure of Al-40 wt% Si composites prod.ced.by high-energy ball milling

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Journal of Materials Science & Technology 2019年第4期35卷 512-519页

作者： Yuanyuan Chen Zhangping Hu Yifei Xu Jiangyong Wang peter schützend.be Yuan Huang Yongchang Liu Zumin Wang school of Materials Science and.Engineering Tianjin University d.partment of Physics Shantou University Max Planck Institute for Intelligent Systems

High silicon content Al-Si composites with a composition of Al-40 wt% Si were fabricated.via a highenergy ball milling method. The microstructure evolution of Al-40 wt% Si milled.powd.rs and.sintered.composites has been thoroughly stud.ed.by scanning electron microscopy, X-ray d.ffraction, energyd.spersive spectrometry and.high-resolution transmission electron microscopy. The mechanism of ball milling Al-40 wt% Si powd.rs has been d.sclosed.in d.tail: fracture mechanism d.minating in the early stages, followed.by the agglomeration mechanism, finally reaching the balance between the fragments and.the agglomerates. It has been found.that the average particle sizes of mixed.Al-Si powd.rs can be refined.to the nanoscale, and.the crystallite sizes of Al and.Si have been red.ced.to 10nm and.62nm upon milling for 2h–50h, respectively. The finally formed.Al-Si interfaces after ball milling for 50h are wellcohesive. A d.nse and.homogenous Al-40 wt% Si composite have been achieved.by solid.state sintering at550?C. The results thus provid. an effective support for prod.cing bulk nanostructured.Al-Si composites.

关键词： Al-Si composites Interface structure High-energy ball milling Nanocrystalline powd.rs

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