Formation et transport de poussières en plasma magnétisé basse pression

Depuis la fin des années 80, les plasmas poussiéreux sont l’objet d’un grand nombre d’études. Plusieurs domaines de la physique des plasmas sont confrontés à la présence de ces parti- cules: en astrophysique, dans les procédés de dépôt ou de gravure, dans les plasmas de fusion thermonucléaire contrôlée. Les plasmas poussiéreux ont très peu été étudiés dans des dé- charges micro-onde basse pression. Il y a une quinzaine d’années encore, il était admis que les probabilités de recombinaisons d’espèces réactives en volume étaient négligeables à cause de la faible densité du gaz. Au LAPLACE, des poussières incandescentes sont observées en plasma RCER d’acéty- lène. La présente étude a pour objectif d’apporter des éléments de réponses sur les méca- nismes liés à la formation, au transport et au chauffage de ces poussières. Ce document présente les résultats obtenus durant ces 4 années de thèse. Le chapitre 1 introduit brièvement l’émergence de la thématique des plasmas poussiéreux, ainsi que certains aspects théoriques importants des décharges multipolaires. Le chapitre 2 détaille le dispositif expérimental ainsi que les différents diagnostiques utilisés durant cette étude: sonde de Langmuir, sonde de Mach, sonde de flux aux parois et imagerie rapide. Le chapitre 3 présente en détail les mécanismes de chargement et de chauffage des poussières. Dans cette partie, des mesures expérimentales ainsi qu’un modèle sont couplés afin d’expliquer l’incandescence et d’estimer la charge des particules. Le chapitre 4 décrit la caractérisation du transport des poussières dans une plasma d’acétylène par imagerie rapide. Dans ce cha- pitre, nous discutons des forces pouvant être responsables de ce transport. Enfin, le chapitre 5 passe en revue les résultats obtenus sur l’interaction plasma surface, à l’aide d’analyses ex-situ ainsi que des mesures de sondes de flux aux parois.Since the late 1980s, dusty plasmas have been the subject of a large number of studies. Several fields of plasma physics are confronted with the presence of these particles: astrophysics, deposition or etching processes, or controlled thermonuclear fusion plasmas. However, few dusty plasma studies have been reported in low pressure microwave discharges. Fifteen years ago, it was accepted that dust particles cannot be formed in the plasma volume, due to the low probability of recombining reactive species, because of the low density of the gas. At LAPLACE, incandescent dusts are observed in RECR acetylene plasma. The present study aims to provide some answers on the mechanisms related to the formation, transportation and heating of dust particles. This document presents the results obtained during these four years of theses. Chapter 1 briefly introduces the emergence of the topic of dusty plasmas, as well as some important theoretical aspects of multipolar discharges. Chapter 2 details the experimental setup and the different diagnostics used during this study: Langmuir probe, Mach probe, wall probe current and rapid imaging. Chapter 3 details the mechanisms for charging and heating dust. In this part, experimental measurements and a model are coupled to explain the incandescence and to estimate the particles charges. Chapter 4 describes the characterization of dust transport in acetylene plasma by rapid imaging. In this chapter, we discuss the forces that can be responsible for this transport. Finally, Chapter 5 reviews the results obtained on the plasma-surface interaction, using ex-situ analyzes as well as measurements of wall probe currents

La Gestion Dynamique des déchets (GDD) : élaboration d'une approche intégrée d'aide à la décision visant à soutenir une gestion systémique et évolutive des déchets

International audienceEn raison des impacts sociaux, économiques et environnementaux associés à la gestion des déchets, il est nécessaire de favoriser les prises de décision qui intègrent chacun de ces aspects. Actuellement, les approches préconisées sont plutôt statiques et linéaires dans leur application, elles ne permettent pas une utilisation optimale des matières disponibles. En conséquence, le choix des technologies pour la gestion des déchets repose souvent sur des paramètres fixes, alors que les systèmes sont en constante évolution. De plus, la validité de prioriser une technologie est directement liée aux impacts associés aux longueurs de trajets, aux modes de transports et aux caractéristiques des routes empruntées. Cependant, les outils disponibles négligent cet aspect dynamique qui est crucial pour réduire la charge des systèmes étudiés. Dans le but d'assurer une gestion durable et dynamique des déchets, la GDD propose une nouvelle approche évolutive permettant d'assurer une alimentation constante vers les technologies favorables dans un système. Pour y parvenir, la GDD repose sur la loi de la conservation de l'énergie qui permet d'équilibrer un réseau tout en considérant les contraintes associées aux transports. Afin de démontrer la portée de la GDD, cet article décrit l'approche, puis présente un exemple d'application

Effect of Hydrocortisone on Mortality and Organ Support in Patients With Severe COVID-19: The REMAP-CAP COVID-19 Corticosteroid Domain Randomized Clinical Trial.

Importance: Evidence regarding corticosteroid use for severe coronavirus disease 2019 (COVID-19) is limited. Objective: To determine whether hydrocortisone improves outcome for patients with severe COVID-19. Design, Setting, and Participants: An ongoing adaptive platform trial testing multiple interventions within multiple therapeutic domains, for example, antiviral agents, corticosteroids, or immunoglobulin. Between March 9 and June 17, 2020, 614 adult patients with suspected or confirmed COVID-19 were enrolled and randomized within at least 1 domain following admission to an intensive care unit (ICU) for respiratory or cardiovascular organ support at 121 sites in 8 countries. Of these, 403 were randomized to open-label interventions within the corticosteroid domain. The domain was halted after results from another trial were released. Follow-up ended August 12, 2020. Interventions: The corticosteroid domain randomized participants to a fixed 7-day course of intravenous hydrocortisone (50 mg or 100 mg every 6 hours) (n = 143), a shock-dependent course (50 mg every 6 hours when shock was clinically evident) (n = 152), or no hydrocortisone (n = 108). Main Outcomes and Measures: The primary end point was organ support-free days (days alive and free of ICU-based respiratory or cardiovascular support) within 21 days, where patients who died were assigned -1 day. The primary analysis was a bayesian cumulative logistic model that included all patients enrolled with severe COVID-19, adjusting for age, sex, site, region, time, assignment to interventions within other domains, and domain and intervention eligibility. Superiority was defined as the posterior probability of an odds ratio greater than 1 (threshold for trial conclusion of superiority >99%). Results: After excluding 19 participants who withdrew consent, there were 384 patients (mean age, 60 years; 29% female) randomized to the fixed-dose (n = 137), shock-dependent (n = 146), and no (n = 101) hydrocortisone groups; 379 (99%) completed the study and were included in the analysis. The mean age for the 3 groups ranged between 59.5 and 60.4 years; most patients were male (range, 70.6%-71.5%); mean body mass index ranged between 29.7 and 30.9; and patients receiving mechanical ventilation ranged between 50.0% and 63.5%. For the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively, the median organ support-free days were 0 (IQR, -1 to 15), 0 (IQR, -1 to 13), and 0 (-1 to 11) days (composed of 30%, 26%, and 33% mortality rates and 11.5, 9.5, and 6 median organ support-free days among survivors). The median adjusted odds ratio and bayesian probability of superiority were 1.43 (95% credible interval, 0.91-2.27) and 93% for fixed-dose hydrocortisone, respectively, and were 1.22 (95% credible interval, 0.76-1.94) and 80% for shock-dependent hydrocortisone compared with no hydrocortisone. Serious adverse events were reported in 4 (3%), 5 (3%), and 1 (1%) patients in the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively. Conclusions and Relevance: Among patients with severe COVID-19, treatment with a 7-day fixed-dose course of hydrocortisone or shock-dependent dosing of hydrocortisone, compared with no hydrocortisone, resulted in 93% and 80% probabilities of superiority with regard to the odds of improvement in organ support-free days within 21 days. However, the trial was stopped early and no treatment strategy met prespecified criteria for statistical superiority, precluding definitive conclusions. Trial Registration: ClinicalTrials.gov Identifier: NCT02735707

Measurement of the differential and double-differential Drell-Yan cross sections in proton-proton collisions at root s=7 TeV

Copyright @ 2013 CERN, for the bene t of the CMS collaboration. This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.Measurements of the differential and double-differential Drell-Yan cross sections are presented using an integrated luminosity of 4.5 (4.8) fb−1 in the dimuon (dielectron) channel of proton-proton collision data recorded with the CMS detector at the LHC at s√ = 7 TeV. The measured inclusive cross section in the Z-peak region (60–120 GeV) is σ(ℓℓ) = 986.4 ± 0.6 (stat.) ± 5.9 (exp. syst.) ± 21.7 (th. syst.) ± 21.7 (lum.) pb for the combination of the dimuon and dielectron channels. Differential cross sections dσ/dm for the dimuon, dielectron, and combined channels are measured in the mass range 15 to 1500 GeV and corrected to the full phase space. Results are also presented for the measurement of the double-differential cross section d2σ/dm d|y| in the dimuon channel over the mass range 20 to 1500 GeV and absolute dimuon rapidity from 0 to 2.4. These measurements are compared to the predictions of perturbative QCD calculations at next-to-leading and next-to-next-to-leading orders using various sets of parton distribution functions.The Austrian Federal Ministry of Science and Research and the Austrian Science Fund; the Belgian Fonds de la Recherche Scienti que, and Fonds voor Wetenschappelijk Onderzoek; the Brazilian Funding Agencies (CNPq, CAPES, FAPERJ, and FAPESP); the Bulgarian Ministry of Education and Science; CERN; the Chinese Academy of Sciences, Ministry of Science and Technology, and National Natural Science Foundation of China; the Colombian Funding Agency (COLCIENCIAS); the Croatian Ministry of Science, Education and Sport; the Research Promotion Foundation, Cyprus; the Ministry of Education and Research, Recurrent nancing contract SF0690030s09 and European Regional Development Fund, Estonia; the Academy of Finland, Finnish Ministry of Education and Culture, and Helsinki Institute of Physics; the Institut National de Physique Nucl eaire et de Physique des Particules / CNRS, and Commissariat a l' Energie Atomique et aux Energies Alternatives / CEA, France; the Bundesministerium f ur Bildung und Forschung, Deutsche Forschungsgemeinschaft, and Helmholtz-Gemeinschaft Deutscher Forschungszentren, Germany; the General Secretariat for Research and Technology, Greece; the National Scienti c Research Foundation, and National Innovation O ce, Hungary; the Department of Atomic Energy and the Department of Science and Technology, India; the Institute for Studies in Theoretical Physics and Mathematics, Iran; the Science Foundation, Ireland; the Istituto Nazionale di Fisica Nucleare, Italy; the Korean Ministry of Education, Science and Technology and the World Class University program of NRF, Republic of Korea; the Lithuanian Academy of Sciences; the Mexican Funding Agencies (CINVESTAV, CONACYT, SEP, and UASLP-FAI); the Ministry of Business, Innovation and Employment, New Zealand; the Pakistan Atomic Energy Commission; the Ministry of Science and Higher Education and the National Science Centre, Poland; the Funda c~ao para a Ci^encia e a Tecnologia, Portugal; JINR, Dubna; the Ministry of Education and Science of the Russian Federation, the Federal Agency of Atomic Energy of the Russian Federation, Russian Academy of Sciences, and the Russian Foundation for Basic Research; the Ministry of Education, Science and Technological Development of Serbia; the Secretar a de Estado de Investigaci on, Desarrollo e Innovaci on and Programa Consolider-Ingenio 2010, Spain; the Swiss Funding Agencies (ETH Board, ETH Zurich, PSI, SNF, UniZH, Canton Zurich, and SER); the National Science Council, Taipei; the Thailand Center of Excellence in Physics, the Institute for the Promotion of Teaching Science and Technology of Thailand, Special Task Force for Activating Research and the National Science and Technology Development Agency of Thailand; the Scienti c and Technical Research Council of Turkey, and Turkish Atomic Energy Authority; the Science and Technology Facilities Council, UK; the US Department of Energy, and the US National Science Foundation

Measurement of associated W plus charm production in pp collisions at √s=7 TeV

Peer reviewe

Measurement of the muon charge asymmetry in inclusive pp →W + X production at s=7 TeV and an improved determination of light parton distribution functions

Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published articles title, journal citation, and DOI.Measurements of the muon charge asymmetry in inclusive pp → W + X production at root s= 7 TeV are presented. The data sample corresponds to an integrated luminosity of 4.7 fb−1 recorded with the CMS detector at the LHC. With a sample of more than 20 million W → μν events, the statistical precision is greatly improved in comparison to previous measurements. These new results provide additional constraints on the parton distribution functions of the proton in the range of the Bjorken scaling variable x from 10−3 to 10−1. These measurements and the recent CMS measurement of associated W þ charm production are used together with the cross sections for inclusive deep inelastic e p scattering at HERA in a next-to-leading-order QCD analysis. The determination of the valence quark distributions is improved, and the strange-quark distribution is probed directly through the leading-order process g þ s → W þ c in proton-proton collisions at the LHC.the Austrian Federal Ministry of Science and Research and the Austrian Science Fund; the Belgian Fonds de la Recherche Scientifique, and Fonds voor Wetenschappelijk Onderzoek; the Brazilian Funding Agencies (CNPq, CAPES, FAPERJ, and FAPESP); the Bulgarian Ministry of Education and Science; CERN; the Chinese Academy of Sciences, Ministry of Science and Technology, and National Natural Science Foundation of China; the Colombian Funding Agency (COLCIENCIAS); the Croatian Ministry of Science, Education and Sport, and the Croatian Science Foundation; the Research Promotion Foundation, Cyprus; the Ministry of Education and Research, Recurrent financing contract SF0690030s09 and European Regional Development Fund, Estonia; the Academy of Finland, Finnish Ministry of Education and Culture, and Helsinki Institute of Physics; the Institut National de Physique Nucléaire et de Physique des Particules/CNRS, and Commissariat à l’Énergie Atomique et aux Énergies Alternatives/CEA, France; the Bundesministerium für Bildung und Forschung, Deutsche Forschungsgemeinschaft, and Helmholtz-Gemeinschaft Deutscher Forschungszentren, Germany; the General Secretariat for Research and Technology, Greece; the National Scientific Research Foundation, and National Innovation Office, Hungary; the Department of Atomic Energy and the Department of Science and Technology, India; the Institute for Studies in Theoretical Physics and Mathematics, Iran; the Science Foundation, Ireland; the Istituto Nazionale di Fisica Nucleare, Italy; the Korean Ministry of Education, Science and Technology and the World Class University program of NRF, Republic of Korea; the Lithuanian Academy of Sciences; the Mexican Funding Agencies (CINVESTAV, CONACYT, SEP, and UASLP-FAI); the Ministry of Business, Innovation and Employment, New Zealand; the Pakistan Atomic Energy Commission; the Ministry of Science and Higher Education and the National Science Centre, Poland; the Fundação para a Ciência e a Tecnologia, Portugal; JINR, Dubna; the Ministry of Education and Science of the Russian Federation, the Federal Agency of Atomic Energy of the Russian Federation, Russian Academy of Sciences, and the Russian Foundation for Basic Research; the Ministry of Education, Science and Technological Development of Serbia; the Secretaría de Estado de Investigación, Desarrollo e Innovación and Programa Consolider-Ingenio 2010, Spain; the Swiss Funding Agencies (ETH Board, ETH Zurich, PSI, SNF, UniZH, Canton Zurich, and SER); the National Science Council, Taipei; the Thailand Center of Excellence in Physics, the Institute for the Promotion of Teaching Science and Technology of Thailand, Special Task Force for Activating Research and the National Science and Technology Development Agency of Thailand; the Scientific and Technical Research Council of Turkey, and Turkish Atomic Energy Authority; the Science and Technology Facilities Council, UK; the U.S. Department of Energy, and the U.S. National Science Foundation. Individuals have received support from the Marie-Curie programme and the European Research Council and EPLANET (European Union); the Leventis Foundation; the A. P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation à la Recherche dans l’Industrie et dans l’Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); the Ministry of Education, Youth and Sports (MEYS) of Czech Republic; the Council of Science and Industrial Research, India; the Compagnia di San Paolo (Torino); the HOMING PLUS programme of Foundation for Polish Science, cofinanced by EU, Regional Development Fund; and the Thalis and Aristeia programmes cofinanced by EU-ESF and the Greek NSRF

Genome-wide patterns of selection in 230 ancient Eurasians

Ancient DNA makes it possible to directly witness natural selection by analyzing samples from populations before, during and after adaptation events. Here we report the first scan for selection using ancient DNA, capitalizing on the largest genome-wide dataset yet assembled: 230 West Eurasians dating to between 6500 and 1000 BCE, including 163 with newly reported data. The new samples include the first genome-wide data from the Anatolian Neolithic culture whose genetic material we extracted from the DNA-rich petrous bone and who we show were members of the population that was the source of Europe’s first farmers. We also report a complete transect of the steppe region in Samara between 5500 and 1200 BCE that allows us to recognize admixture from at least two external sources into steppe populations during this period. We detect selection at loci associated with diet, pigmentation and immunity, and two independent episodes of selection on height

Measurement of the ratio of the inclusive 3-jet cross section to the inclusive 2-jet cross section in pp collisions at root s=7 TeV and first determination of the strong coupling constant in the TeV range

A measurement is presented of the ratio of the inclusive 3-jet cross section to the inclusive 2-jet cross section as a function of the average transverse momentum, , of the two leading jets in the event. The data sample was collected during 2011 at a proton-proton centre-of-mass energy of 7 TeV with the CMS detector at the LHC, corresponding to an integrated luminosity of 5.0 fb(-1). The strong coupling constant at the scale of the Z boson mass is determined to be alpha(S)(M-Z) = 0.1148 +/- 0.0014 (exp.) +/- 0.0018 (PDF) +/- 0.0050 (theory), by comparing the ratio in the range 0.42 < 1.39 TeV to the predictions of perturbative QCD at next-to-leading order. This is the first determination of alpha(S)(M-Z) from measurements at momentum scales beyond 0.6 TeV. The predicted ratio depends only indirectly on the evolution of the parton distribution functions of the proton such that this measurement also serves as a test of the evolution of the strong coupling constant. No deviation from the expected behaviour is observed

Measurements of differential and double-differential Drell–Yan cross sections in proton–proton collisions at √s = 8TeV

Measurements of the differential and double-differential Drell–Yan cross sections in the dielectron and dimuon channels are presented. They are based on proton–proton collision data at vs = 8TeV recorded with the CMS detector at the LHC and corresponding to an integrated luminosity of 19.7 fb-1. The measured inclusive cross section in the ZZ peak region (60–120 GeV), obtained from the combination of the dielectron and dimuon channels, is 1138±8(exp)±25(theo)±30(lumi)\,pb, where the statistical uncertainty is negligible. The differential cross section ds/dm in the dilepton mass range 15–2000 GeV is measured and corrected to the full phase space. The double-differential cross section d2s/dmd|y| is also measured over the mass range 20 to 1500 GeV and absolute dilepton rapidity from 0 to 2.4. In addition, the ratios of the normalized differential cross sections measured at vs = 7 and 8 TeV are presented. These measurements are compared to the predictions of perturbative QCD at next-to-leading and next-to-next-to-leading (NNLO) orders using various sets of parton distribution functions (PDFs). The results agree with the NNLO theoretical predictions computed with fewz 3.1 using the CT10 NNLO and NNPDF2.1 NNLO PDFs. The measured double-differential cross section and ratio of normalized differential cross sections are sufficiently precise to constrain the proton PDFs.[…] the Secretaría de Estado de Investigación, Desarrollo e Innovación and Programa Consolider-Ingenio 2010, Spain […