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Collisionless shock acceleration of protons in a plasma slab produced in a gas j.t by the collision of two laser-driven hydrodynamic shockwaves

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Matter and Radiation at Extremes 2024年第2期9卷 12-25页

作者： j.-R.Marquès L.Lancia P.Loiseau P.Forestier-Colleoni M.Tarisien E.Atukpor V.Bagnoud C.Brabetz F.Consoli j.Domange F.Hannachi P.Nicolaï M.Salvadori B.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance CEA DAMDIF91297 Arpajon CedexFrance UniversitéParis-Saclay CEALMCE91680 Bruyères-le-ChatelFrance CENBG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany University of Darmstadt Schloßgartenstr.764289 DarmstadtGermany ENEA Fusion and Technologies for Nuclear Safety Department C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly CELIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance UniversitéParis-Saclay CEALIDYL91191 Gif-sur-YvetteFrance

We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas j.t[Marquès et al.,*** 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas *** tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by Coulomb *** the front side of the gas j.t is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are *** forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(CSA).The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe *** refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma *** with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas *** parameters are in good agreement with those required for CSA.

关键词： acceleration hydrodynamic collision

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从机械机器人到智能机器人:人工智能的图像学

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外国文学研究 2024年第3期46卷 1-7页

作者： W.j.T.米切尔韦清琦(译) 美国芝加哥大学东南大学外国语学院

智能机器人将人类带入了自原子弹、电灯或是印刷术以来最伟大的科技革命之中,同时智能机器也能走火入魔这一构思也向来是科幻作品的核心想象。纵观媒体发明的历史长河,对人工智能的恐慌并不新鲜,人们曾认为书写的发明和照相术将扼杀记... 详细信息

智能机器人将人类带入了自原子弹、电灯或是印刷术以来最伟大的科技革命之中,同时智能机器也能走火入魔这一构思也向来是科幻作品的核心想象。纵观媒体发明的历史长河,对人工智能的恐慌并不新鲜,人们曾认为书写的发明和照相术将扼杀记忆和绘画,现在又照例指责数码正在毁灭模拟技术的独一性。人类应该冷静下来,采取对症下药的态度。有必要解构关于人与机器之差异的想象,而毋需躲避与智能机器人的交互谈话。人类物种虽然在作茧自缚,但同时又以进化与生态智能为基础,努力建设可持续全球体系。图像学研究的图像和文字同时包括了机器和人类的作品,因而相关的研究者应明确自己的任务:就文字与图像和智能机器人展开对话,在上述人类的生存努力中谋求与智能机器人携手合作。

关键词：智能机器人人工智能机器图像学传媒人文

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Long-term olfactory loss post-COVID-19:Pathobiology and potential therapeutic strategies

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World j.urnal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 148-155页

作者： Sarah Kim j.hn B.Finlay Tiffany Ko Bradley j.Goldstein Department of Head and Neck Surgery&Communication Sciences Duke UniversityDurhamNorth CarolinaUSA Medical Scientist Training Program Duke UniversityDurhamNorth CarolinaUSA Department of Neurobiology Duke UniversityDurhamNorth CarolinaUSA

An acute loss of smell emerged as a striking symptom present in roughly half of the people infected with the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)virus in the early phases of the COVID-19 *** most COVID-19 patients,olfaction recovers over the course of a few ***,a lasting partial or complete loss of smell,often associated with distorted olfactory perceptions termed parosmia,has emerged as a widespread problem impacting at least 5%-10%of those who experience anosmia due to *** inability to offer effective therapies to this hyposmic or anosmic population,comprising millions of patients,highlights an enormous unmet need for the medical ***,we summarize the current understanding of the pathobiology causing acute olfactory loss due to SARS-CoV-2 infection,focusing on how the virus interacts with the peripheral olfactory system,a maj.r site of viral *** also explore the problem of long-COVID olfactory dysfunction,which may accompany other persistent systemic disorders collectively termed postacute sequelae of ***,we discuss an emerging model focused on unresolved immune cell activity driving ongoing ***,we review current and future therapeutic approaches aimed at restoring olfactory function.

关键词： hyposmia inflammation long-COVID parosmia

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地球演化历史中氧逸度变化对壳幔循环启动、风化和超大陆循环的指示

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Science Bulletin 2024年第1期69卷 97-102页

作者：王瑞邬绍宸 Roberto F.Weinberg William j.Collins Peter A.Cawood State Key Laboratory of Geological Processes and Mineral Resources Institute of Earth SciencesChina University of GeosciencesBeijing 100083China Frontiers Science Center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing 100083China School of Earth Atmosphere and EnvironmentMonash UniversityClayton VIC 3800Australia The Institute for Geoscience Research Curtin UniversityPerth WA 6102Australia

We apply a zircon redox index to a global compilation of detrital zircons to track the variation of oxidation state,expressed asΔFMQ,through Earth's *** from I-type rocks,which comprise mantle and crustal igneous protoliths,including tonalite–trondhj.mite–granodiorites(TTGs),generally have a high oxidation state(ΔFMQ>0).In contrast,zircons from igneous rocks derived from supracrustal source rocks(S-type)are commonly reduced(ΔFMQ0 over the last 3 *** that the redox state of magmas is independent of crustal thickness and silica variation,and elevated values are likely more closely related to tectonic setting,we suggest that the consistent averageΔFMQ>0 from ca.3.5 Ga onwards relates to recycling of oceanic lithosphere back into the mantle in what eventually became established as subduction *** more reduced magmas associated with sedimentary sources,became established at 2.6 Ga,presumably in response to continental rocks rising above sealevel,and follow peaks of productivity associated with the supercontinent cycle.

关键词： Oxidation state Supercontinent Weathering Subduction Zircon Granite

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《全部的真相》

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环球科学 2024年第9期 91-91页

作者： P.j.E.皮布尔斯武星(译) 不详

出版:中信出版集团如果你曾思考过“客观”和“主观”,那你可能也会好奇:科学家总结出来的规律到底是一种客观实在,还是一种主观总结。因为说到底,即便是被认作“客观规律”的很多成果也不过是在目前的条件下没有被证伪。这多少让人疑... 详细信息

出版:中信出版集团如果你曾思考过“客观”和“主观”,那你可能也会好奇:科学家总结出来的规律到底是一种客观实在,还是一种主观总结。因为说到底,即便是被认作“客观规律”的很多成果也不过是在目前的条件下没有被证伪。这多少让人疑惑于宇宙的“本质”。当一位获得诺贝尔物理学奖的天文学家尝试跳出自己熟悉的领域,开始思考这类带有哲学意味的问题时,你不仅可以看到他扎实的专业基础,也能看到大量跨专业的巧思和火花。

关键词：诺贝尔物理学奖哲学意味客观实在跨专业真相天文学家客观规律好奇

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Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science Review 2024年第1期11卷 8-10页

作者： David j.Bottj.r Department of Earth Sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

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Global weirding at mass extinction horizons

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National Science Review 2024年第1期11卷 10-12页

作者： Gregory j.Retallack Department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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Degradation and resynthesis of chlorophyll during increased oxidative stress and prolonged darkness differ between annual and perennial flax(Linum L.)

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Oil Crop Science 2024年第2期9卷 121-130页

作者： Kenyon j. Nisbett Abida Alokozai Su Hyun Elizabeth Ko G. Adam Mott j.son C.L. Browna Department of Biological Sciences University of Toronto ScarboroughTorontoONCanada Department of Cell&Systems Biology University of TorontoTorontoONCanada Centre for the Analysis of Genome Evolution&Function University of TorontoTorontoONCanada

Among plants,there is considerable variation in lifespan:annuals live less than one year,whereas perennials live for several years,with the longest-living perennial having survived 43,600 *** proposed by the Disposable Soma Theory,this lifespan variation among plants likely reflects differential investment of limited energy and nutrient resources,with perennials investing more energy and nutrients into biomolecular maintenance compared to annuals in order to ensure persistence over multiple *** differential investment may be particularly important during periods of exogenous stress,which are known to accelerate biomolecular *** present study evaluated this hypothesis using annual and perennial flax(Linum L.)subj.cted to two exogenous stressors—increased oxidative stress(i.e.,foliar H2O2spraying)and complete prolonged *** chlorophyll has been shown to exhibit degradation in response to changes in environmental conditions,we utilized changes in chlorophyll levels during and after periods of exogenous stress to evaluate our *** predicted that i)perennials would exhibit a slower rate of chlorophyll degradation during exposure to exogenous stressors compared to annuals,and ii)perennials would exhibit a faster rate of chlorophyll resynthesis following such exposure compared to *** levels before,during,and after exposure to both exogenous stressors were measured in two separate trails,once using image colour analysis and once using *** chlorophyll degradation rates in response to oxidative stress did not differ between annuals and perennials,contrary to our predictions,chlorophyll resynthesis rates following such exposure were significantly higher in perennials,as *** plants were subj.cted to complete prolonged darkness,chlorophyll degradation rates were significantly lower in perennials than annuals,as predicted;however,when plants were subsequently reintroduced to natural photoperiod,ch

关键词： Ageing Life history Maximum lifespan Oxidative stress Somatic maintenance

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A Modified Lagrange Method for Solving Convex Quadratic Optimization Problems

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Open j.urnal of Optimization 2024年第1期13卷 1-20页

作者： Twum B. Stephen Avoka j.hn Christian j. Etwire School of Mathematical Science C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana Department of Mathematics University for Development Studies Tamale Ghana

In this paper, a modified version of the Classical Lagrange Multiplier method is developed for convex quadratic optimization problems. The method, which is evolved from the first order derivative test for optimality of the Lagrangian function with respect to the primary variables of the problem, decomposes the solution process into two independent ones, in which the primary variables are solved for independently, and then the secondary variables, which are the Lagrange multipliers, are solved for, afterward. This is an innovation that leads to solving independently two simpler systems of equations involving the primary variables only, on one hand, and the secondary ones on the other. Solutions obtained for small sized problems (as preliminary test of the method) demonstrate that the new method is generally effective in producing the required solutions.

关键词： Quadratic Programming Lagrangian Function Lagrange Multipliers Optimality Conditions Subsidiary Equations Modified Lagrange Method

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Diagnostic Dilemma of Intracardiac Mass: Tumor versus Thrombus-Case Series and Systematic Review

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j.urnal of Biosciences and Medicines 2024年第7期12卷 141-150页

作者： Indira Acharya Ashik Pokharel Raktim Ghosh Christopher j. Haas Department of Internal Medicine Internal Medicine Residency Program Medstar Health Baltimore MD USA Department of Cardiology MedStar Union Memorial Hospital MedStar Health Baltimore MD USA School of Medicine Georgetown University Washington D.C. USA

Background: The differential diagnosis for intracavitary cardiac masses is limited, typically including vegetations, tumors, or thrombi. Cardiac thrombi can often mimic cardiac tumors on imaging, creating a diagnostic challenge. Primary cardiac tumors are rare and usually benign, whereas most cardiac tumors result from metastases, commonly originating from malignancies in the breast, lung, or melanoma. Aim: This report highlights the importance of distinguishing various cardiac masses based on clinical presentations, clinical courses, and radiological features. Case Presentation: We describe two cases of cardiac masses with unique and diverse clinical features. Each case posed significant diagnostic challenges due to their distinct presentations and clinical progressions. Conclusion: These cases underscore the importance of considering both benign and metastatic origins in the differential diagnosis of intracavitary cardiac masses. Accurate differentiation between thrombi and tumors is crucial for appropriate management and treatment.

关键词： Echocardiography Cardiac Masses Arrhythmias Cardiac Magnetic Resonance Imaging Cardiac Thrombi

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