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20篇 您的检索式:作者名="S.Weber"
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1基于IMRT时代的第八版AJCC/UICC鼻咽癌临床分期建议显示文摘目的准确的分期系统对癌症的治疗至关重要。随着癌症分期和治疗方法的演变,需要不断评价分期的适用性和改进性。方法基于第7版AJCC/UICC分期回顾性分析香港和中国大陆2个肿瘤中心收治的1609例接受调强放射治疗的首诊无转移鼻咽癌患者临床资料,所有患者治疗前均行核磁共振分期评估。结果无其他T3、T4期解剖结构受侵患者中,伴有咀嚼肌间隙(翼内肌和/或翼外肌)侵犯、椎前肌侵犯及咽旁间隙侵犯的三组患者之间0s相近。伴广泛软组织(上述侵犯结构以外的软组织)受侵患者OS与伴有颅内侵犯或颅神经侵犯相似。仅2%患者锁骨上窝以上淋巴结转移者直径〉6cm,其0s率与下颈淋巴结转移者类似。用下颈(环状软骨尾侧缘水平以下)代替锁骨上窝并不影响N分期之间的风险差异性。采用推荐的T、N分期,T。N。、T。N,期0s相近。结论经AJCC/UICC分期筹备委员会审阅后,建议第8版分期应将翼内肌/翼外肌从T。降到T:期,增加椎前肌为L期,用下颈取代锁骨上窝,将淋巴结最大直径〉6cm合并归为N,期,将T。、N,期统一归为Ⅳ。期。这些改变不仅使得相邻分期间风险差异性更好,而且使得临床实践性与全球适用性之间达到最佳平衡。潘建基 Wai Tong Ng 宗井凤 Lucy L.K.Chan Brian O' Sullivan 林少俊 Henry C.K.Sze 陈韵彬 Horace C.W.Choi 郭巧娟 Wai Kuen Kan 肖友平 Xu Wei Quynh Thu Le Christine M.Glastonbury A.Dimtrios Colevas Randal S.Weber Jatin P.Shah Anne W.M.Lee 2016中华放射肿瘤学杂志2016,25,3:65
2P3: An installation for high-energy density plasma physics and ultra-high intensity laserematter interaction at ELI-Beamlines显示文摘ELI-Beamlines(ELI-BL),one of the three pillars of the Extreme Light Infrastructure endeavour,will be in a unique position to perform research in high-energy-density-physics(HEDP),plasma physics and ultra-high intensity(UHI)ð>10^(22) W=cm^(2)) lasereplasma interaction.Recently the need for HED laboratory physics was identified and the P3(plasma physics platform)installation under construction in ELI-BL will be an answer.The ELI-BL 10 PW laser makes possible fundamental research topics from high-field physics to new extreme states of matter such as radiation-dominated ones,high-pressure quantum ones,warm dense matter(WDM)and ultra-relativistic plasmas.HEDP is of fundamental importance for research in the field of laboratory astrophysics and inertial confinement fusion(ICF).Reaching such extreme states of matter now and in the future will depend on the use of plasma optics for amplifying and focusing laser pulses.This article will present the relevant technological infrastructure being built in ELI-BL for HEDP and UHI,and gives a brief overview of some research under way in the field of UHI,laboratory astrophysics,ICF,WDM,and plasma optics.S.Weber S.Bechet S.Borneis L.Brabec M.Bucka E.Chacon-Golcher M.Ciappina M.DeMarco A.Fajstavr K.Falk E.-R.Garcia J.Grosz Y.-J.Gu J.-C.Hernandez M.Holec P.Janecka M.Jantac M.Jirka H.Kadlecova D.Khikhlukha O.Klimo G.Korn D.Kramer D.Kumar T.Lastovicka P.Lutoslawski L.Morejon V.Olsovcova M.Rajdl O.Renner B.Rus S.Singh M.Smid M.Sokol R.Versaci R.Vrana M.Vranic J.Vyskocil A.Wolf Q.Yu 2017Matter and Radiation at Extremes2017,2,4:8
3Studies of laser-plasma interaction physics with low-density targets for direct-drive inertial confinement schemes显示文摘Comprehensive understanding and possible control of parametric instabilities in the context of inertial confinement fusion (ICF) remains achallenging task. The details of the absorption processes and the detrimental effects of hot electrons on the implosion process require as mucheffort on the experimental side as on the theoretical and simulation side. This paper describes a proposal for experimental studies on nonlinearinteraction of intense laser pulses with a high-temperature plasma under conditions corresponding to direct-drive ICF schemes. We propose todevelop a platform for laser-plasma interaction studies based on foam targets. Parametric instabilities are sensitive to the bulk plasma temperatureand the density scale length. Foam targets are sufficiently flexible to allow control of these parameters. However, investigationsconducted on small laser facilities cannot be extrapolated in a reliable way to real fusion conditions. It is therefore necessary to performexperiments at a multi-kilojoule energy level on medium-scale facilities such asOMEGAor SG-III. An example of two-plasmon decay instabilityexcited in the interaction of two laser beams is considered.V.Tikhonchuk Y.J.Gu O.Klimo J.Limpouch S.Weber 2019Matter and Radiation at Extremes2019,4,4:3
4Temperature dependence of parametric instabilities in the context of the shock-ignition approach to inertial confinement fusion显示文摘The role of the coronal electron plasma temperature for shock-ignition conditions is analysed with respect to the dominant parametric processes: stimulated Brillouin scattering, stimulated Raman scattering, two-plasmon decay(TPD), Langmuir decay instability(LDI) and cavitation. TPD instability and cavitation are sensitive to the electron temperature. At the same time the reflectivity and high-energy electron production are strongly affected. For low plasma temperatures the LDI plays a dominant role in the TPD saturation. An understanding of laser–plasma interaction in the context of shock ignition is an important issue due to the localization of energy deposition by collective effects and hot electron production.This in turn can have consequences for the compression phase and the resulting gain factor of the implosion phase.S.Weber C.Riconda 2015High Power Laser Science and Engineering2015,3,1:3
5Raman-Brillouin interplay for inertial confinement fusion relevant laser-plasma interaction显示文摘The co-existence of the Raman and Brillouin backscattering instability is an important issue for inertial confinement fusion. The present paper presents extensive one-dimensional(1D) particle-in-cell(PIC) simulations for a wide range of parameters extending and complementing previous findings. PIC simulations show that the scenario of reflectivity evolution and saturation is very sensitive to the temperatures, intensities, size of plasma and boundary conditions employed. The Langmuir decay instability is observed for rather small k_(epw)λ_D but has no influence on the saturation of Brillouin backscattering, although there is a clear correlation of Langmuir decay instability modes and ion-fractional decay for certain parameter ranges. Raman backscattering appears at any intensity and temperature but is only a transient phenomenon. In several configurations forward as well as backward Raman scattering is observed. For the intensities considered, I λ_o^2 above 10^(15) W μm^2/cm^2, Raman is always of bursty nature. A particular setup allows the simulation of multi-speckle aspects in which case it is found that Raman is self-limiting due to strong modifications of the distribution function. Kinetic effects are of prime importance for Raman backscattering at high temperatures. No unique scenario for the saturation of Raman scattering or Raman–Brillouin competition does exist. The main effect in the considered parameter range is pump depletion because of large Brillouin backscattering. However, in the low k_(epw)λ_D regime the presence of ion-acoustic waves due to the Langmuir decay instability from the Raman created electron plasma waves can seed the ion-fractional decay and affect the Brillouin saturation.C.Riconda S.Weber 2016High Power Laser Science and Engineering2016,4,3:2
6Studies of laser-plasma interaction physics with low-density targets for direct-drive inertial confinement fusion on the Shenguang III prototype显示文摘The physics of laser-plasma interaction is studied on the Shenguang III prototype laser facility under conditions relevant to inertial confinement fusion designs.A sub-millimeter-size underdense hot plasma is created by ionization of a low-density plastic foam by four high-energy(3.2 kJ)laser beams.An interaction beam is fired with a delay permitting evaluation of the excitation of parametric instabilities at different stages of plasma evolution.Multiple diagnostics are used for plasma characterization,scattered radiation,and accelerated electrons.The experimental results are analyzed with radiation hydrodynamic simulations that take account of foam ionization and homogenization.The measured level of stimulated Raman scattering is almost one order of magnitude larger than that measured in experiments with gasbags and hohlraums on the same installation,possibly because of a greater plasma density.Notable amplification is achieved in high-intensity speckles,indicating the importance of implementing laser temporal smoothing techniques with a large bandwidth for controlling laser propagation and absorption.V.T.Tikhonchuk T.Gong N.Jourdain O.Renner F.P.Condamine K.Q.Pan W.Nazarov L.Hudec J.Limpouch R.Liska M.Krus F.Wang D.Yang S.W.Li Z.C.Li Z.Y.Guan Y.G.Liu T.Xu X.S.Peng X.M.Liu Y.L.Li J.Li T.M.Song J.M.Yang S.E.Jiang B.H.Zhang W.Y.Huo G.Ren Y.H.Chen W.Zheng Y.K.Ding K.Lan S.Weber 2021Matter and Radiation at Extremes2021,6,2:2
7Initial combination of linagliptin and metformin improves glycaemic control in type 2 diabetes: a randomized, double‐blind, placebo‐controlled study显示文摘T.Haak T.Meinicke R.Jones S.Weber M. vonEynatten H.‐J.Woerle 2012Diabetes, Obesity and Metabolism2012,,6:1
8Sintering of High Wear Resistant Metal Matrix Composites显示文摘S.Weber W.Theisen 2007Adv Eng Mater2007,,3:1
9Safety of Completion Thyroidectomy Following Unilateral Lobectomy for Well‐Differentiated Thyroid Cancer显示文摘Michael E.Kupferman Susan J.Mandel LiesjeDiDonato PatWolf Randal S.Weber 2009The Laryngoscope2009,,7:1
10Design,installation and commissioning of the ELI-Beamlines high-power,high-repetition rate HAPLS laser beam transport system to P3显示文摘The design and the early commissioning of the ELI-Beamlines laser facility’s 30 J,30 fs,10 Hz HAPLS(High-repetitionrate Advanced Petawatt Laser System)beam transport(BT)system to the P3 target chamber are described in detail.It is the world’s first and with 54 m length,the longest distance high average power petawatt(PW)BT system ever built.It connects the HAPLS pulse compressor via the injector periscope with the 4.5 m diameter P3 target chamber of the plasma physics group in hall E3.It is the largest target chamber of the facility and was connected first to the BT system.The major engineering challenges are the required high vibration stability mirror support structures,the high pointing stability optomechanics as well as the required levels for chemical and particle cleanliness of the vacuum vessels to preserve the high laser damage threshold of the dielectrically coated high-power mirrors.A first commissioning experiment at low pulse energy shows the full functionality of the BT system to P3 and the novel experimental infrastructure.S.Borneis T.Laštovickaˇ M.Sokol T.-M.Jeong F.Condamine O.Renner V.Tikhonchuk H.Bohlin A.Fajstavr J.-C.Hernandez N.Jourdain D.Kumar D.Modranskýˇ A.Pokorný A.Wolf S.Zhai G.Korn S.Weber 2021High Power Laser Science and Engineering2021,9,2:0
11Fiduciary Responsibility: Facilitating Public Trust in Automated Decision Making显示文摘Automated decision-making systems are being increasingly deployed and affect the public in a multitude of positive and negative ways.Governmental and private institutions use these systems to process information according to certain human-devised rules in order to address social problems or organizational challenges.Both research and real-world experience indicate that the public lacks trust in automated decision-making systems and the institutions that deploy them.The recreancy theorem argues that the public is more likely to trust and support decisions made or influenced by automated decision-making systems if the institutions that administer them meet their fiduciary responsibility.However,often the public is never informed of how these systems operate and resultant institutional decisions are made.A“black box”effect of automated decision-making systems reduces the public’s perceptions of integrity and trustworthiness.Consequently,the institutions administering these systems are less able to assess whether the decisions are just.The result is that the public loses the capacity to identify,challenge,and rectify unfairness or the costs associated with the loss of public goods or benefits.The current position paper defines and explains the role of fiduciary responsibility within an automated decision-making system.We formulate an automated decision-making system as a data science lifecycle(DSL)and examine the implications of fiduciary responsibility within the context of the DSL.Fiduciary responsibility within DSLs provides a methodology for addressing the public’s lack of trust in automated decision-making systems and the institutions that employ them to make decisions affecting the public.We posit that fiduciary responsibility manifests in several contexts of a DSL,each of which requires its own mitigation of sources of mistrust.To instantiate fiduciary responsibility,a Los Angeles Police Department(LAPD)predictive policing case study is examined.We examine the development and deployment by the LAPD of predictive policing technology and identify several ways in which the LAPD failed to meet its fiduciary responsibility.Shannon B.Harper Eric S.Weber 2022Journal of Social Computing2022,3,4:0
12The L4n laser beamline of the P3-installation:Towards high-repetition rate high-energy density physics at ELI-Beamlines显示文摘The P3 installation of ELI-Beamlines is conceived as an experimental platform for multiple high-repetition-rate laser beams spanning time scales from femtosecond via picosecond to nanosecond.The upcoming L4n laser beamline will provide shaped nanosecond pulses of up to 1.9 kJ at a maximum repetition rate of 1 shot/min.This beamline will provide unique possibilities for high-pressure,high-energy-density physics,warm dense matter,and laser–plasma interaction experiments.Owing to the high repetition rate,it will become possible to obtain considerable improvements in data statistics,in particular,for equation-of-state data sets.The nanosecond beam will be coupled with short sub-picosecond pulses,providing high-resolution diagnostic tools by either irradiating a backlighter target or driving a betatron setup to generate energetic electrons and hard X-rays.N.Jourdain U.Chaulagain M.Havlik D.Kramer D.Kumar V.T.Tikhonchuk G.Korn S.Weber 2021Matter and Radiation at Extremes2021,6,1:0
13Fast magnetic energy dissipation in relativistic plasma induced by high order laser modes显示文摘Fast magnetic field annihilation in a collisionless plasma is induced by using TEM(1,0) laser pulse. The magnetic quadrupole structure formation, expansion and annihilation stages are demonstrated with 2.5-dimensional particle-in-cell simulations. The magnetic field energy is converted to the electric field and accelerate the particles inside the annihilation plane. A bunch of high energy electrons moving backwards is detected in the current sheet. The strong displacement current is the dominant contribution which induces the longitudinal inductive electric field.Y.J.Gu Q.Yu O.Klimo T.Zh.Esirkepov S.V.Bulanov S.Weber G.Korn 2016High Power Laser Science and Engineering2016,4,2:0
14Plasma optics in the context of high intensity lasers显示文摘The use of plasmas provides a way to overcome the low damage threshold of classical solid-state based optical materials,which is the main limitation encountered in producing and manipulating intense and energetic laser pulses.Plasmas can directly amplify or alter the characteristics of ultra-short laser pulses via the three-wave coupling equations for parametric processes.The strong-coupling regime of Brillouin scattering(sc-SBS)is of particular interest:recent progress in this domain is presented here.This includes the role of the global phase in the spatio-temporal evolution of the three-wave coupled equations for backscattering that allows a description of the coupling dynamics and the various stages of amplification from the initial growth to the so-called self-similar regime.The understanding of the phase evolution allows control of the directionality of the energy transfer via the phase relation between the pulses.A scheme that exploits this coupling in order to use the plasma as a wave plate is also suggested.H.Peng J.-R.Marques L.Lancia F.Amiranoff R.L.Berger S.Weber C.Riconda 2019Matter and Radiation at Extremes2019,4,6:0
15Macroscopic lasereplasma interaction under strong non-local transport conditions for coupled matter and radiation显示文摘Reliable simulations of laseretarget interaction on the macroscopic scale are burdened by the fact that the energy transport is very often non-local.This means that the mean-free-path of the transported species is larger than the local gradient scale lengths and transport can be no longer considered diffusive.Kinetic simulations are not a feasible option due to tremendous computational demands,limited validity of the collisional operators and inaccurate treatment of thermal radiation.This is the point where hydrodynamic codes with non-local radiation and electron heat transport based on first principles emerge.The simulation code PETE(Plasma Euler and Transport Equations)combines both of them with a laser absorption method based on the Helmholtz equation and a radiation diffusion scheme presented in this article.In the case of modelling ablation processes it can be observed that both,thermal and radiative,transport processes are strongly non-local for laser intensities of 10^(13) W=cm^(2) and above.In this paper simulations for various laser intensities and different ablator materials are presented,where the non-local and diffusive treatments of radiation transport are compared.Significant discrepancies are observed,supporting importance of non-local transport for inertial confinement fusion related studies as well as for pre-pulse generated plasma in ultra-high intensity laseretarget interaction.J.Nikl M.Holec M.Zeman M.Kucharík J.Limpouch S.Weber 2018Matter and Radiation at Extremes2018,3,3:0
16Collective absorption of laser radiation in plasma at sub-relativistic intensities显示文摘Processes of laser energy absorption and electron heating in an expanding plasma in the range of irradiances Iλ^2=1015–1016 W·μm^2/cm^2 are studied with the aid of kinetic simulations.The results show a strong reflection due to stimulated Brillouin scattering and a significant collisionless absorption related to stimulated Raman scattering near and below the quarter critical density.Also presented are parametric decay instability and resonant excitation of plasma waves near the critical density.All these processes result in the excitation of high-amplitude electron plasma waves and electron acceleration.The spectrum of scattered radiation is significantly modified by secondary parametric processes,which provide information on the spatial localization of nonlinear absorption and hot electron characteristics.The considered domain of laser and plasma parameters is relevant for the shock ignition scheme of inertial confinement fusion.Y.J.Gu O.Klimo Ph.Nicolai S.Shekhanov S.Weber V.T.Tikhonchuk 2019High Power Laser Science and Engineering2019,7,3:0
17Time evolution of stimulated Raman scattering and two-plasmon decay at laser intensities relevant for shock ignition in a hot plasma显示文摘Laser–plasma interaction(LPI)at intensities 1015–1016 W·cm^-2 is dominated by parametric instabilities which can be responsible for a significant amount of non-collisional absorption and generate large fluxes of high-energy nonthermal electrons.Such a regime is of paramount importance for inertial confinement fusion(ICF)and in particular for the shock ignition scheme.In this paper we report on an experiment carried out at the Prague Asterix Laser System(PALS)facility to investigate the extent and time history of stimulated Raman scattering(SRS)and two-plasmon decay(TPD)instabilities,driven by the interaction of an infrared laser pulse at an intensity^1.2×1016 W·cm^-2 with a^100μm scalelength plasma produced from irradiation of a flat plastic target.The laser pulse duration(300 ps)and the high value of plasma temperature(~4 ke V)expected from hydrodynamic simulations make these results interesting for a deeper understanding of LPI in shock ignition conditions.Experimental results show that absolute TPD/SRS,driven at a quarter of the critical density,and convective SRS,driven at lower plasma densities,are well separated in time,with absolute instabilities driven at early times of interaction and convective backward SRS emerging at the laser peak and persisting all over the tail of the pulse.Side-scattering SRS,driven at low plasma densities,is also clearly observed.Experimental results are compared to fully kinetic large-scale,two-dimensional simulations.Particle-in-cell results,beyond reproducing the framework delineated by the experimental measurements,reveal the importance of filamentation instability in ruling the onset of SRS and stimulated Brillouin scattering instabilities and confirm the crucial role of collisionless absorption in the LPI energy balance.G.Cristoforetti L.Antonelli D.Mancelli S.Atzeni F.Baffigi F.Barbato D.Batani G.Boutoux F.D'Amato J.Dostal R.Dudzak E.Filippov Y.J.Gu L.Juha O.Klimo M.Krus S.Malko A.S.Martynenko Ph.Nicolai V.Ospina S.Pikuz O.Renner J.Santos V.T.Tikhonchuk J.Trela S.Viciani L.Volpe S.Weber L.A.Gizzi 2019High Power Laser Science and Engineering2019,7,3:0
18Collective coherent emission of electrons in strong laser fields and perspective for hard x-ray lasers显示文摘Coherent motion of particles in a plasma can imprint itself on radiation.The recent advent of high-power lasers—allowing the nonlinear inverse Compton-scattering regime to be reached—has opened the possibility of looking at collective effects in laser–plasma interactions.Under certain conditions,the collective interaction of many electrons with a laser pulse can generate coherent radiation in the hard x-ray regime.This perspective paper explains the limitations under which such a regime might be attained.E.G.Gelfer A.M.Fedotov O.Klimo S.Weber 2024Matter and Radiation at Extremes2024,9,2:0
19Direct acceleration of an annular attosecond electron slice driven by near-infrared Laguerre-Gaussian laser显示文摘A new near-infrared direct acceleration mechanism driven by Laguerre-Gaussian laser is proposed to stably accelerate and concentrate electron slice both in longitudinal and transversal directions in vacuum.Three-dimensional simulations show that a 2-μm circularly polarized LG_(p)^(l)(p=0,l=1,σ_(2)=-1)laser can directly manipulate attosecond electron slices in additional dimensions(angular directions)and give them annular structures and angular momentums.These annular vortex attosecond electron slices are expected to have some novel applications such as in the collimation of antiprotons in conventional linear accelerators,edge-enhancement electron imaging,structured X-ray generation,and analysis and manipulation of nanomaterials.C.Jiang W.P.Wang S.Weber H.Dong Y.X.Leng R.X.Li Z.Z.Xu 2021High Power Laser Science and Engineering2021,9,3:0
20Plasma optics:A perspective for high-power coherent light generation and manipulation显示文摘Over the last two decades,the importance of fully ionized plasmas for the controlled manipulation of high-power coherent light has increased considerably.Many ideas have been put forward on how to control or change the properties of laser pulses such as their frequency,spectrum,intensity,and polarization.The corresponding interaction with a plasma can take place either in a self-organizing way or by prior tailoring.Considerable work has been done in theoretical studies and in simulations,but at present there is a backlog of demand for experimental veri-fication and the associated detailed characterization of plasma-optical elements.Existing proof-of-principle experiments need to be pushed to higher power levels.There is little doubt that plasmas have huge potential for future use in high-power optics.This introduction to the special issue of Matter and Radiation at Extremes devoted to plasma optics sets the framework,gives a short historical overview,and briefly describes the various articles in this collection.C.Riconda S.Weber 2023Matter and Radiation at Extremes2023,8,2:0
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