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Phase noise modeling in LC oscillators implemented in SiGe technology

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Journal of Semiconductors 2013年第2期34卷 60-66页

作者： M.Bouhouche S.Latreche C.Gontrand universite Mentouri Faculte des Sciences de l'IngenieurDepartement d'ElectroniqueLaboratoire Hyperfrequence & Semi-conducteur(LHS)25000ConstantineAlegria universite de lyon VilleurbanneF-69621France

This paper addresses phase noise analysis of a radiofrequency LC oscillator built around a SiGe heterojunction bipolar transistor （HBT） realized in a 0.35 um BiCMOS process, as an active device. First, we give a brief background to SiGe HBT device physics. The key point is to initiate quantitative analysis on the influence of defects induced during extrinsic base implantation on electric performances of this device. These defects are responsible for the current fluctuations at the origin of low frequency noise in BiCMOS technologies. Next, we investigate the effect of implantation defects as a source of noise in semiconductors on the phase noise of a radiofrequency LC oscillator. We observe their influence on the oscillator phase noise, and we quantify the influence of their energy distribution in the semiconductor gap. Second, we give a behavioral model of an LC oscillator con- taining a SiGe HBT as an active device. The key goal is to study the susceptibility of a radiofrequency oscillator built around a SiGe HBT to phase noise disturbance sources. Based on the time variance behavior of phase noise in oscillators, transient simulations （in the time domain） were used to analyze the time-dependent noise sensitivity of the oscillator.

关键词： SiGe heterojunction radiofrequency mixed-mode simulations oscillator phase noise

Molecular Networks Regulating Meristem Homeostasis

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Molecular Plant 2018年第7期11卷 883-885页

作者： Jan Traas Laboratoire de Reproduction et Developpement des Plantes INRA CNRS ENSL UCB Lyon I Universite de Lyon 46 allee d'ltalie 69364 Lyon Cedex 07 France

The shoot apical meristem （SAM）, which produces all the aerial parts of the plant, plays a major role in the establish- ment of plant architecture. In many higher plants, the SAM has a stereotypic organization in zones with different func- tions. At the summit of the dome-shaped meristem is a popu- lation of stem cells （called the central zone）, required for meristem maintenance. Part of the cells produced by the central zone will enter a differentiation pathway and their descendants will serve as founders for the stems and lateral organs at the meristem periphery （or peripheral zone）. During the last decades, much of the research on the SAM has focused on three major signaling cascades required for its function：

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Preoperative biliary drainage for resectable or borderline resectable periampullary tumor: what is the best management?

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Hepatobiliary Surgery and Nutrition 2019年第4期8卷 398-400页

作者： Julie Perinel Mustapha Adham Service de chirurgie Digestive Hopital Edouard HerriotHospices Civils de LyonLyonFrance Faculte de Medecine de lyon Universite Claude Bernard Lyon 1(UCBL1)LyonFrance

Management of preoperative biliary drainage (PBD) in patients undergoing pancreaticoduodenectomy (PD) is still debated. Obstructive jaundice is associated with a proinflammatory state, impaired immune function and disturbances in coagulation. Patients with jaundice are at high risk to develop renal dysfunction and bacteriobilia. In this context, PBD was traditionally performed before surgery to improve postoperative outcomes.

关键词： impaired biliary jaundice

Redox evolution of western Tianshan subduction zone and its effect on deep carbon cycle

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Geoscience Frontiers 2020年第3期11卷 915-924页

作者： Renbiao Tao Lijuan Zhang Lifei Zhang The MOE Key Laboratory of Orogenic Belt and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China Univ lyon Ens de LyonUniversite Lyon 1CNRSUMR 5276 LGL-TPEF-69622VilleurbanneFrance

Knowing the phase relations of carbon-bearing phases at high-pressure(HP) and high-temperature(HT) condition is essential for understanding the deep carbon cycle in the subduction *** particular,the phase relation of carbon-bearing phases is also strongly influenced by redox condition of subduction zones,which is poorly *** we summarized the phase relations of carbon-bearing phases(calcite,aragonite,dolomite,magnesite,graphite,hydrocarbon) in HP metamorphic rocks(marble,metapelite,eclogite) from the Western Tianshan subduction zone and high-pressure *** prograde progress of subduction,carbonates in altered oceanic crust change from Ca-carbonate(calcite) to Ca,Mg-carbonate(dolomite),then finally to Mgcarbonate(magnesite) via Mg-Ca cation exchange reaction between silicate and carbonate,while calcite in sedimentary calcareous ooze on oceanic crust directly transfers to high-pressure aragonite in marble or amorphous CaCO3 in subduction *** evolution also plays a significant effect on the carbon speciation in the Western Tianshan subduction *** prograde oxygen fugacity of the Western Tianshan subduction zone was constrained by mineral assemblage of garnet-omphacite from FMQ-1.9 to FMQ-2.5 at its metamorphic peak(maximum P-T) *** comparison with redox conditions of other subduction zones,Western Tianshan has the lowest oxygen *** and light hydrocarbon inclusions were ubiqutously identified in Western Tianshan HP metamorphic rocks and speculated to be formed from reduction of Fe-carbonate at low redox condition,which is also confirmed by high-pressure experimental *** on petrological observation and high-pressure simulation,a polarized redox model of reducing slab but oxidizing mantle wedge in subduction zone is proposed,and its effect on deep carbon cycle in subduction zones is further discussed.

关键词： Oxygen fugacity Western Tianshan Subduction zone Deep carbon cycle Polarized redox model

Once upon a time biomass burning in the western Alps: Nesting effects of climate and local drivers on long-term subalpine fires

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Forest Ecosystems 2022年第2期9卷 257-266页

作者： Christopher Carcaillet Benjamin Boulley Frederique Carcaillet Univ lyon Universite Claude Bernard Lyon 1CNRSENTPE(UMR LEHNA)F-69622VilleurbanneFrance Paris Sciences&Lettres University(PSL) Ecole Pratique des Hautes Etudes(EPHE)F-75014ParisFrance NaturCom Chair Universite de MontpellierF-34000MontpellierFrance MARBEC(universite de Montpellier CNRSIfremerIRD)F-34000MontpellierFrance

Background:The present article questions the relative importance of local-and large-scale processes on the long-term dynamics of fire in the subalpine belt in the western *** study is based on soil charcoal dating and identification,several study sites in contrasting environmental conditions,and sampling of soil charcoal along the elevation gradient of each *** on local differences in biomass combustion,we hypothesize that local-scale or landscape-scale processes have driven the fire history,while combustion homogeneity supports the hypothesis of the importance of large-scale or macro-ecological processes,especially ***:Biomass burning during the Holocene resulted from the nesting effects of climate,land use,and altitude,but was little influenced by slope exposure(north versus south),soil(dryness,pH,depth),and *** mid-Holocene(6500–2700 cal BP)was an important period for climate-driven biomass burning in the subalpine ecosystems of the western Alps,while fires over the last 2500 years appear much more episodic,prompting us to speculate that human activity has played a vital role in their ***:Our working hypothesis that the strength of local drivers should offset the effects of regional climate is not *** homogeneity of the fire regime between sites thus underscores that climate was the main driver during the Holocene of the western ***-term subalpine fires are controlled by climate at the millennial *** conditions matter for little in determining variability at the century *** mid-Holocene was a chief period for climatic biomass burning in the subalpine zone,while fires during the late Holocene appear much more episodic,suggesting that social drivers has exercised key function on their control.

关键词： Biomass burning Subalpine forest Climate Landscape Pedoanthracology Radiocarbon dating Pyrogenic carbon

Modeling and numerical investigation of slow crack growth and crack arrest in ceramic polycrystals

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Theoretical & Applied Mechanics Letters 2013年第5期3卷 53-57页

作者： Bassem El Zoghbi Rafael Estevez Christian Olagnon Laboratoire SIMAP UMR CNRS 5266 Grenoble-INP UJF Universite' de Grenoble Laboratoire MATEIS UMR CNRS 5510 INSA Lyon Universite' de Lyon69621 France

ntergranular slow crack growth in zirconia polycrystal is described with a cohesive zone model that simulate mechanically the reaction-rupture mechanism underlying stress and environ- mentally assisted failure. A 2D polycrystal is considered with cohesive surfaces inserted along the grain boundaries. The anisotropic elastic modulus and grain-to-grain misorientation are accounted for together with an initial stress state related to the processing. A minimum load threshold is shown to originate from the onset of the reaction-rupture mechanism to proceed where a minimum traction is reached locally and from the magnitude of the initial compression stresses. This work aims at providing reliable predictions in long lasting applications of ceramics.

关键词： zirconia ceramic slow crack growth cohesive zone intergranular failure

The LEAFY floral regulator displays pioneer transcription factor properties

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Molecular Plant 2021年第5期14卷 829-837页

作者： Xuelei Lai Romain Blanc-Mathieu Loïc GrandVuillemin Ying Huang Arnaud Stigliani Jeremy Lucas Emmanuel Thevenon Jeanne Loue-Manifel Laura Turchi Hussein Daher Eugenia Brun-Hernandez Gilles Vachon David Latrasse Moussa Benhamed Renaud Dumas Chloe Zubieta François Parcy Laboratoire Physiologie Cellulaire et Vegetale Universite Grenoble AlpesCNRSCEAINRAEIRIG-DBSCI-LPCV17 avenue des martyrs38054GrenobleFrance universite Paris-Saclay CNRSINRAEUniversite d'EvryInstitute of Plant Sciences Paris-Saclay(IPS2)91405OrsayFrance The Bioinformatics Centre Department of Biology and Biotech and Research Innovation CentreUniversity of CopenhagenOle Maalces Vej 5DK2200 Copenhagen NDenmark Laboratoire Reproduction et Developpement des Plantes Universite de LyonENS de LyonUCB Lyon 1CNRSINRA69342 LyonFrance Institut de Biologie Structurale Universite Grenoble AlpesCEACNRSGrenobleFrance universite de Paris Institute of Plant Sciences Paris-Saclay(IPS2)75006 ParisFrance

Pioneer transcription factors(TFs)are a special category of TFs with the capacity to bind to closed chromatin regions in which DNA is wrapped around histones and may be highly ***,pioneer TFs are able to modify the chromatin state to initiate gene *** plants,LEAFY(LFY)is a master floral regulator and has been suggested to act as a pioneer TF in ***,we demonstrate that LFY is able to bind both methylated and non-methylated DNA using a combination of in vitro genomewide binding experiments and structural *** between regions bound by LFY in vivo and chromatin accessibility data suggest that a subset of LFY bound regions is occupied by *** confirm that LFY is able to bind nucleosomal DNA in vitro using reconstituted ***,we show that constitutive LFY expression in seedling tissues is sufficient to induce chromatin accessibility in the LFY direct target genes APETALA1 and *** together,our study suggests that LFY possesses key pioneer TF features that contribute to launching the floral gene expression program.

关键词： flower development pioneer transcription factor gene regulation chromatin remodeling

Enhancing heat transfer at the micro-scale using elastic turbulence

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Theoretical & Applied Mechanics Letters 2015年第3期5卷 103-106页

作者： R.D.Whalley W.M.Abed D.J.C.Dennis R.J.Poole School of Engineering University of Liverpool LMFA Universite de LyonEcole Centrale de Lyon

Small concentrations of a high-molecular-weight polymer have been used to create so-called ＂elastic tur- bulence＂ in a micro-scale serpentine channel geometry. It is known that the interaction of large elastic stresses created by the shearing motion within the fluid flow with streamline curvature of the serpentine geometry leads initially to a purely-elastic instability and then the generation of elastic turbulence. We show that this elastic turbulence enhances the heat transfer at the micro-scale in this geometry by up to 300% under creeping flow conditions in comparison to that achieved by the equivalent Newtonian fluid flow.

关键词： Elastic turbulence Viscoelasticity Serpentine channel Micro-mixing Heat transfer

Energy Filtering and Coaxial Detection of the Backscattered Electrons in Scanning Electron Microscope

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Chinese Physics Letters 2000年第9期17卷 637-639页

作者： JIANG Chang-Zhong P.Morin N.Rosenberg Department of Physics Wuhan UniversityWuhan 430072 Departement de Physique des Materiaux Universite Claude Bernard Lyon I69622 Villeurbanne CedexFrance

A new detection system in scanning electron microscope,which filters in energy and detects the backscattered electrons close to the microscope axis,is *** technique ameliorates the dependence of the *** tering coefficient on atomic number,and suppresses effectively the relief contrast at the same *** this new method is very suitable to the composition analysis.

关键词： Electron scattered system