37 research outputs found
Energy transferred to the substrate surface during reactive magnetron sputtering of aluminum in Ar/O2 atmosphere
International audienceA study of the reactive sputtering of aluminum was carried out by coupling energy flux measurements at the substrate location with conventional diagnostics of the gas phase and analyses of the deposited films. The main purpose was to get some insight into the elementary mechanisms involved at the substrate surface during the film growth in the well known metal and oxide regimes and at the transitions from one to another. Measurements were carried out in front of a 10 cmAl target at a power of 400W (i.e. 5 W/cm2) and a total pressure of 0.6 Pa. The flow rate ratio (O2/O2+Ar) was varied in the range 0 to 50 %. Different kinetics and values of energy transfer, denoting different involved mechanisms, were evidenced at metal-oxide (increasing flow rate) and oxide-metal (decreasing flow rate) transitions. The metal-oxide transition was found to be a progressive process, in agreement with optical emission spectroscopy and deposit analysis, characterized by an increase of the energy flux that could be due to the oxidation of the growing metal film. On the contrary, oxide-metal transition is abrupt, and a high energy released at the beginning that could not be attributed to a chemical reaction. The possible effect of O-ions at this step was discussed
Influence of step structure on preferred orientation relationships of Ag deposited on Ni(111)
Previous studies have shown that the orientation relationships which develop
in hetero-epitaxy are strongly influenced by the alignment of steps in the
deposit with the pre-existing steps of the substrate. In this paper we use a
combination of experiments with computer simulations to identify the important
influence of substrate step structure on the eventual orientation relationships
that develop in the deposit. We have made use of Ag deposited on Ni as it has
been used extensively as a model system for the study of hetero-epitaxy. This
system displays a large lattice mismatch of 16%. It is shown that on any
surface vicinal to Ni(111), which has two possible kinds of steps
(A-steps with {100} ledges and B-steps with {111} ledges), a Ag deposit adopts
a single orientation relationship because only A-steps remain stable in the
presence of Ag.Comment: Acta Materialia, Elsevier, In pres
Decim v2
The original publication is available at www.springerlink.comIn this paper, we present Decimv2, a stream cipher hardware- oriented selected for the phase 3 of the ECRYPT stream cipher project eSTREAM. As required by the initial call for hardware-oriented stream cipher contribution, Decimv2 manages 80-bit secret keys and 64-bit public initialization vectors. The design of Decimv2 combines two filtering mechanisms: a nonlinear Boolean filter over a LFSR, followed by an irregular decimation mechanism called the ABSG. Since designers have been invited to demonstrate flexibility of their design by proposing vari-ants that take 128-bit keys, we also present a 128-bit security version of Decim called Decim-128
Death and the Societies of Late Antiquity
Ce volume bilingue, comprenant un ensemble de 28 contributions disponibles en français et en anglais (dans leur version longue ou abrĂ©gĂ©e), propose dâĂ©tablir un Ă©tat des lieux des rĂ©flexions, recherches et Ă©tudes conduites sur le fait funĂ©raire Ă lâĂ©poque tardo-antique au sein des provinces de lâEmpire romain et sur leurs rĂ©gions limitrophes, afin dâouvrir de nouvelles perspectives sur ses Ă©volutions possibles. Au cours des trois derniĂšres dĂ©cennies, les transformations considĂ©rables des mĂ©thodologies dĂ©ployĂ©es sur le terrain et en laboratoire ont permis un renouveau des questionnements sur les populations et les pratiques funĂ©raires de lâAntiquitĂ© tardive, pĂ©riode marquĂ©e par de multiples changements politiques, sociaux, dĂ©mographiques et culturels. Lâapparition de ce qui a Ă©tĂ© initialement dĂ©signĂ© comme une « Anthropologie de terrain », qui fut le dĂ©but de la dĂ©marche archĂ©othanatologique, puis le rĂ©cent dĂ©veloppement dâapproches collaboratives entre des domaines scientifiques divers (archĂ©othanatologie, biochimie et gĂ©ochimie, gĂ©nĂ©tique, histoire, Ă©pigraphie par exemple) ont Ă©tĂ© dĂ©cisives pour le renouvellement des problĂ©matiques dâĂ©tude : rĂ©vision dâanciens concepts comme apparition dâaxes dâanalyse inĂ©dits. Les recherches rassemblĂ©es dans cet ouvrage sont articulĂ©es autour de quatre grands thĂšmes : lâĂ©volution des pratiques funĂ©raires dans le temps, lâidentitĂ© sociale dans la mort, les ensembles funĂ©raires en transformation (organisation et topographie) et les territoires de lâempire (du cĆur aux marges). Ces Ă©tudes proposent un rĂ©examen et une rĂ©vision des donnĂ©es, tant anthropologiques quâarchĂ©ologiques ou historiques sur lâAntiquitĂ© tardive, et rĂ©vĂšlent, Ă cet Ă©gard, une mosaĂŻque de paysages politiques, sociaux et culturels singuliĂšrement riches et complexes. Elles accroissent nos connaissances sur le traitement des dĂ©funts, lâemplacement des aires funĂ©raires ou encore la structure des sĂ©pultures, en rĂ©vĂ©lant une diversitĂ© de pratiques, et permettent au final de relancer la rĂ©flexion sur la maniĂšre dont les sociĂ©tĂ©s tardo-antiques envisagent la mort et sur les Ă©lĂ©ments permettant dâidentifier et de dĂ©finir la diversitĂ© des groupes qui les composent. Elles dĂ©montrent ce faisant que nous pouvons vĂ©ritablement apprĂ©hender les structures culturelles et sociales des communautĂ©s anciennes et leurs potentielles transformations, Ă partir de lâĂ©tude des pratiques funĂ©raires.This bilingual volume proposes to draw up an assessment of the recent research conducted on funerary behavior during Late Antiquity in the provinces of the Roman Empire and on their borders, in order to open new perspectives on its possible developments. The considerable transformations of the methodologies have raised the need for a renewal of the questions on the funerary practices during Late Antiquity, a period marked by multiple political, social, demographic and cultural changes. The emergence field anthropology, which was the beginning of archaeothanatology, and then the recent development of collaborative approaches between various scientific fields (archaeothanatology, biochemistry and geochemistry, genetics, history, epigraphy, for example), have been decisive. The research collected in this book is structured around four main themes: Evolution of funerary practices over time; Social identity through death; Changing burial grounds (organisation and topography); Territories of the Empire (from the heart to the margins). These studies propose a review and a revision of the data, both anthropological and archaeological or historical on Late Antiquity, and reveal a mosaic of political, social, and cultural landscapes singularly rich and complex. In doing so, they demonstrate that we can truly understand the cultural and social structures of ancient communities and their potential transformations, based on the study of funerary practices
COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study
Background:
The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms.
Methods:
International, prospective observational study of 60â109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms.
Results:
âTypicalâ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (â€â18 years: 69, 48, 23; 85%), older adults (â„â70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each Pâ<â0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country.
Interpretation:
This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men
Un systÚme de dictionnaires électroniques pour les mots simples du français
Courtois Blandine. Un systÚme de dictionnaires électroniques pour les mots simples du français. In: Langue française, n°87, 1990. Dictionnaires électroniques du français, sous la direction de Blandine Courtois et Max Silberztein. pp. 11-22
Dictionnaires électroniques du français
Courtois Blandine, Silberztein Max. Dictionnaires électroniques du français. In: Langue française, n°87, 1990. Dictionnaires électroniques du français, sous la direction de Blandine Courtois et Max Silberztein. pp. 3-4
Dictionnaires électroniques du français
Courtois Blandine, Silberztein Max. Dictionnaires électroniques du français. In: Langue française, n°87, 1990. Dictionnaires électroniques du français, sous la direction de Blandine Courtois et Max Silberztein. pp. 3-4
Procédé de préparation de films minces monocristallins
The invention relates to a process for preparing single-crystal thin films of pure metals or alloys, by deposition and growth of grains on a (0001) sapphire having a miscut comprised between 0.2° and 5°, and oriented towards a specific plane. It also relates to a single-crystal thin film obtainable by such a process and uses thereof.L'invention concerne un procĂ©dĂ© de prĂ©paration de films minces monocristallins de mĂ©taux ou d'alliages purs, par dĂ©pĂŽt et croissance de grains sur un saphir (0001) prĂ©sentant une mauvaise dĂ©coupe comprise entre 0,2° et 5°, et orientĂ©s vers un plan spĂ©cifique. L'invention concerne Ă©galement un film mince monocristallin pouvant ĂȘtre obtenu par un tel procĂ©dĂ© et ses utilisations