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High-energy hybrid femtosecond laser system demonstrating 2 × 10 PW capability

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High Power Laser science and Engineering 2020年第4期8卷 108-122页

作者： Fran?ois Lureau Guillaume Matras Olivier Chalus Christophe Derycke Thomas Morbieu Christophe Radier Olivier Casagrande sébastien laux sandrine Ricaud Gilles Rey Alain Pellegrina Caroline Richard Laurent Boudjemaa Christophe simon-Boisson Andrei Baleanu Romeo Banici Andrei Gradinariu Constantin Caldararu Bertrand De Boisdeffre Petru Ghenuche Andrei Naziru Georgios Kolliopoulos Liviu Neagu Razvan Dabu Ioan Dancus Daniel Ursescu Thales LAs France Thales systems Romania Extreme Light Infrastructure – Nuclear Physics ‘Horia Hulubei' National Institute for Physics and Nuclear Engineering University of Bucharest Faculty of Physics

We report on a two-arm hybrid high-power laser system(HPLs) able to deliver 2 × 10 PW femtosecond pulses,developed at the Bucharest-Magurele Extreme Light Infrastructure Nuclear Physics(ELI-NP) Facility. A hybrid frontend(FE) based on a Ti:sapphire chirped pulse amplifier and a picosecond optical parametric chirped pulse amplifier based on beta barium borate(BBO) crystals, with a cross-polarized wave(XPW) filter in between, has been *** delivers 10 mJ laser pulses, at 10 Hz repetition rate, with more than 70 nm spectral bandwidth and high-intensity contrast, in the range of 1013:1. The high-energy Ti:sapphire amplifier stages of both arms were seeded from this common FE. The final high-energy amplifier, equipped with a 200 mm diameter Ti:sapphire crystal, has been pumped by six 100 J nanosecond frequency doubled Nd:glass lasers, at 1 pulse/min repetition rate. More than 300 J output pulse energy has been obtained by pumping with only 80% of the whole 600 J available pump energy. The compressor has a transmission efficiency of 74% and an output pulse duration of 22.7 fs was measured, thus demonstrating that the dual-arm HPLs has the capacity to generate 10 PW peak power femtosecond pulses. The reported results represent the cornerstone of the ELI-NP 2 × 10 PW femtosecond laser facility, devoted to fundamental and applied nuclear physics research.

关键词： lasers high-power laser pulses ultra-short laser pulses

High-energy hybrid femtosecond laser system demonstrating 2×10 PW capability

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High Power Laser science and Engineering 2020年第4期8卷 104-118页

作者： François Lureau Guillaume Matras Olivier Chalus Christophe Derycke Thomas Morbieu Christophe Radier Olivier Casagrande sébastien laux sandrine Ricaud Gilles Rey Alain Pellegrina Caroline Richard Laurent Boudjemaa Christophe simon-Boisson Andrei Baleanu Romeo Banici Andrei Gradinariu Constantin Caldararu Bertrand De Boisdeffre Petru Ghenuche Andrei Naziru Georgios Kolliopoulos Liviu Neagu Razvan Dabu Ioan Dancus Daniel Ursescu Thales LAs France 78990 ElancourtFrance Thales systems Romania 060071 BucurestiRomania Extreme Light Infrastructure-Nuclear Physics ‘Horia Hulubei’National Institute for Physics and Nuclear Engineering077125 Bucharest MagureleRomania University of Bucharest Faculty of Physics077125 Bucharest MagureleRomania

We report on a two-arm hybrid high-power laser system(HPLs)able to deliver 2×10 PW femtosecond pulses,developed at the Bucharest-Magurele Extreme Light Infrastructure Nuclear Physics(ELI-NP)Facility.A hybrid frontend(FE)based on a Ti:sapphire chirped pulse amplifier and a picosecond optical parametric chirped pulse amplifier based on beta barium borate(BBO)crystals,with a cross-polarized wave(XPW)filter in between,has been *** delivers 10 mJ laser pulses,at 10 Hz repetition rate,with more than 70 nm spectral bandwidth and high-intensity contrast,in the range of 1013:*** high-energy Ti:sapphire amplifier stages of both arms were seeded from this common *** final high-energy amplifier,equipped with a 200 mm diameter Ti:sapphire crystal,has been pumped by six 100 J nanosecond frequency doubled Nd:glass lasers,at 1 pulse/min repetition *** than 300 J output pulse energy has been obtained by pumping with only 80%of the whole 600 J available pump *** compressor has a transmission efficiency of 74%and an output pulse duration of 22.7 fs was measured,thus demonstrating that the dual-arm HPLs has the capacity to generate 10 PW peak power femtosecond *** reported results represent the cornerstone of the ELI-NP 2×10 PW femtosecond laser facility,devoted to fundamental and applied nuclear physics research.

关键词： lasers high-power laser pulses ultra-short laser pulses

Targeting the P2X7 receptor in microglial cells to prevent brain inflammation

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Neural Regeneration Research 2020年第7期15卷 1245-1246页

作者： Lin-Hua Jiang sébastien Roger school of Biomedical sciences Faculty of Biological SciencesUniversity of LeedsSino-UK Joint Laboratory of Brain Function and Injury and Department of Physiology and NeurobiologyXinxiang Medical UniversityXinxiangHenan ProvinceChina EA4245 TransplantationImmunology and InflammationFaculty of MedicineUniversity of ToursToursFrance

Microglial cells are the key innate immune cells in the brain and they are crucial in maintaining brain parenchyma *** physiological conditions,microglial cells assume a ramified morphology with a small cell body and an extensive network of fine processes,which secrete neurotrophic factors and patrol the surroundings in search for pathogens and eliminate cellular debris via *** cells express a repertoire of pattern recognition receptors(PRRs)that enable them to detect diverse danger-associated molecular patterns(DAMPs)released from damaged cells or cells under stress,or pathogen-associated molecular patterns generated by pathogens during infection.

关键词： IL ATP APP Targeting the P2X7 receptor in microglial cells to prevent brain inflammation

Coupling ground-level panoramas and aerial imagery for change detection

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Geo-spatial Information science 2016年第3期19卷 222-232页

作者： Nehla Ghouaiel sébastien Lefèvre Institute of Research in Computer science and Random systems Universitéde Bretagne-SudUMR 6074 IRISAVannesFrance

Geographic landscapes in all over the world may be subject to rapid changes induced,for instance,by urban,forest,and agricultural *** such kind of changes is usually achieved through remote ***,obtaining regular and up-to-date aerial or satellite images is found to be a high costly process,thus preventing regular updating of land cover ***,in this paper,we propose a low-cost solution based on the use of groundlevel geo-located landscape panoramic photos providing high spatial resolution information of the *** photos can be acquired from various sources:digital cameras,smartphone,or even web ***,since the acquisition is performed at the ground level,the users’immediate surroundings,as sensed by a camera device,can provide information at a very high level of precision,enabling to update the land cover type of the geographic *** the described herein method,we propose to use inverse perspective mapping(inverse warping)to transform the geo-tagged ground-level 360◦photo onto a top-down view as if it had been acquired from a nadiral aerial *** re-projected,the warped photo is compared to a previously acquired remotely sensed image using standard techniques such as *** differences in orientation,resolution,and geographical extent between the top-down view and the aerial image are addressed through specific processing steps(***).Experiments on publicly available data-sets made of both ground-level photos and aerial images show promising results for updating land cover maps with mobile ***,the proposed approach contributes to the crowdsourcing efforts in geo-information processing and mapping,providing hints on the evolution of a landscape.

关键词： Image analysis remote sensing change detection crowdsourcing mobile mapping panoramic photos

Analogy between adsorption and sorption： An elementary mechanistic approach. I. Monolayer adsorption and sorption without solvent cluster formation

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Chinese Journal of Chemical Engineering 2017年第12期25卷 1740-1749页

作者： Pierre schaetzel sébastien Thomas Hasna Louahlia Gualous Laboratoire Universitaire des sciences Appliquées de Cherbourg Université de Caen IUT de Caen Boulevard Marechal Juin 14032 Caen cedex France Institut de chimie et procédés pour l'énergie l'environnement et la santé Université de Strasbourg 25 rue Becquerel 67087 Strasbourg cedex 2 France

The elementary mechanistic model of adsorption and sorption is based on a simple hypothesis： the adsorption sites are uniformly distnbuted on the surface of the pore walls in the adsorbent, the sorption sites are uniformly distributed in the volume of the polymer. In this first paper we will analyze the simple case where one solute molecule is only allowed to occupy a single adsorption or sorption site. A common elementary occupation law of the free sites is assumed： the differential increase of the number of the adsorbed/sorbed molecules is proportional to the differential increase of the activity of the solute and the concentration of the free （non-occupied） sites in the solid. The proportionality coefficient is called affinity coefficient depending on the solid/solute couple and on the temperature and independent of the concentration of the solute. In adsorption the concentration of the free sites is a surface concentration on the pore walls and in sorption it is expressed by the molarity. The simple monolayer adsorption law of Jovanovic is obtained： n = no（1 - e KP） where n is the number of moles adsorbed when the pressure is P. no is the total number of adsorption sites and K the affinity coefficient for adsorption. The sorption law writes： a = 1/k [Ф/1-Ф] ＋ 1-r/k In [1 ＋ 1/r Ф/1-Ф] where Ф, r and k hold respectively for the volume fraction of the solvent in the polymer, for the ratio of the molar volumes of the solvent to the elementary polymer chain containing one single adsorption site and for the sorption affinity coefficient. The confrontation of these equations to experimental isotherms is satisfactory in comparison with the classical Langmuir and Flory-Huggins equations： the best results are obtained for adsorption of vapors on a 5A zeolite and for all analyzed sorption results.

关键词： Adsorption isotherms sorption isotherms Flory-Huggins theory Langmuir equation

A new age in understanding adult hippocampal neurogenesis in Alzheimer’s disease

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Neural Regeneration Research 2022年第12期17卷 2615-2618页

作者： Maya A.Hanspal sébastien Gillotin MRL London Discovery MSDLondon Bioscience Innovation CentreLondonUK

several lines of evidence have established that proliferation and differentiation of neural stem cells into neurons within the sub-granular zone of the dentate gyrus,a process named adult hippocampal neurogenesis,contribute to maintaining healthy cognitive functions throughout *** rate of adult hippocampal neurogenesis decreases with aging and a premature impairment of adult hippocampal neurogenesis has been observed both in animal models of Alzheimer’s disease and human post-mortem *** causal relationship between adult hippocampal neurogenesis and the development of Alzheimer’s disease pathology has,however,not been *** is partly due to the limitation of recapitulating the development of Alzheimer’s disease pathology in rodent models and the lack of translatable biomarkers to identify tractable targets in *** it is tempting to postulate that adult hippocampal neurogenesis could be leveraged to improve cognitive deficits in Alzheimer’s disease,consensual results have yet to be reached to fully explore this *** this review,we discuss how the recent progress in identifying molecular pathways in adult hippocampal neurogenesis provides a good framework to initiate strategies for drug-based intervention in neurodegenerative diseases,especially in Alzheimer’s *** outline how discrepancies in pre-clinical disease models and experimental methodology have resulted in contradictory findings and propose a shift towards using more translatable approaches to model neurogenesis in Alzheimer’s *** particular,we review how exploring novel experimental paradigms including the use of human induced pluripotent stem cells and more complex cell culture systems,as well as standardizing protocols used to investigate evidence of neurogenesis in human tissues,could deliver deeper mechanistic insights that would kick-start innovative drug discovery efforts to promote healthy aging and cellular rejuvenation.

关键词： adult hippocampal neurogenesis Alzheimer’s disease cognition human tissue induced pluripotent stem cell mouse models neurodegeneration therapeutics tractable target

Error Estimates for 1D Asymptotic Models in Coaxial Cables with Non-Homogeneous Cross-section

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Advances in Applied Mathematics and Mechanics 2012年第6期4卷 647-664页

作者： sébastien Imperiale Patrick Joly Department of Applied Physics and Applied Mathematics Columbia UniversityNY 10027USA INRIA Rocquencourt POemsdomaine de Voluceau78153 Le ChesnayFrance

This paper is the first contribution towards the rigorous justification of asymptotic 1D models for the time-domain simulation of the propagation of electromagnetic waves in coaxial *** general objective is to derive error estimates between the"exact"solution of the full 3D model and the"approximate"solution of the 1D model known as the Telegraphist’s equation.

关键词： Coaxial cables Telegraphist’s equation error estimates non-homogeneous crosssection

safe-event pruning in spacecraft conjunction management

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Astrodynamics 2023年第4期7卷 401-413页

作者： sébastien Henry Roberto Armellin Thibault Gateau Guggenheim school of Aerospace Engineering Georgia Institute of TechnologyAtlantaGA 30332USA Te Punaha Atea-space Institute The University of AucklandAuckland 1010New Zealand Department of Aerospace Vehicles Design and Control Institut Superieur de I'Aeronautique et de I'EspaceToulouse 31055France

spacecraft conjunction management plays a crucial role in the mitigation of space *** a conjunction event occurs,resources and time are spent analyzing,planning,and potentially maneuvering the *** work contributes to a subpart of the problem:Confidently identifying events that will not lead to a high collision probability,and therefore do not require further *** method reduces the dimensionality of the data via principal component analysis(PCA)on a subset of ***-risk regions are then determined by clustering the projected data,and events that do not belong to a high-risk cluster are pruned.A genetic algorithm(GA)is developed to optimize the number of clusters and feature selection of the ***,an ensemble learning framework is proposed to combine the suboptimal models for better *** results show that the first set of parameters pruned approximately 50%of the events in the testing set with no false negatives,whereas the second set of parameters pruned 70%of the events and maintained a near-perfect *** results could benefit the optimization of operational resources and allow operators to focus better on the events of interest.

关键词： space situational awareness collision avoidance genetic algorithm(GA) ensemble learning

Activity Enhancement of MgCl2-supported Ziegler-Natta Catalysts by Lewis-acid Pre-treatment for Ethylene Polymerization

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Chinese Journal of Polymer science 2019年第10期37卷 1031-1038,I0006页

作者： Matthieu Humbert sébastien Norsic Jean Raynaud Vincent Monteil UMR 5265 Laboratoire de Chimie Catalyse Polymères et Procédés (C2P2) Université de Lyon

Ziegler-Natta precatalysts were synthetized from Lewis-base-modified-MgCl2 supports and treated by various Lewis acids,prior to activation by triethylaluminum, in order to increase their activity in ethylene polymerization. BCl3 provided the highest increase in activity. Interestingly, polymerization results showed no substantial modification of polymer properties, which is consistent with that Lewis acid only promotes the creation of new active sites, after activation by TEA, possessing very similar features to the original ones achievable with conventional precatalysts(i.e. without Lewis-acid treatment).

关键词： Ziegler-Natta catalysis Ethylene polymerization Heterogeneous catalysis Lewis acids