84 research outputs found
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
Self-healing glassy thin films for high temperatures applications
Les matĂ©riaux vitreux en couches minces sont des candidats prometteurs comme revĂȘtements de protection pour des applications Ă haute tempĂ©rature. Toutefois, en raison de sollicitations thermiques et/ou mĂ©caniques dans les conditions dâutilisation, ces matĂ©riaux peuvent se fissurer. Des Ă©tudes antĂ©rieures ont montrĂ© que des verres auto-cicatrisants sous forme massive peuvent ĂȘtre Ă©laborĂ©s par incorporation de particules actives. Celles-ci, lors de lâendommagement du matĂ©riau, sâoxydent Ă haute tempĂ©rature pour former des oxydes fluides qui sâĂ©coulent dans la fissure et forment un "nouveau" verre par rĂ©action avec la matrice environnante. En nous appuyant sur ces rĂ©sultats, nos travaux ont eu pour objectif de transposer ce concept vers des matĂ©riaux vitreux dĂ©posĂ©s en couches minces, et ainsi dâenvisager des applications en tant que revĂȘtement. Nous avons montrĂ© la faisabilitĂ© de mise en forme de ces revĂȘtements innovants, par alternance de couches vitreuses et dâagent cicatrisant, aux moyens de lâablation par laser pulsĂ© et de lâĂ©vaporation par bombardement Ă©lectronique. Une premiĂšre Ă©tude a consistĂ© en lâoptimisation des paramĂštres de dĂ©pĂŽt et leur influence sur lâhomogĂ©nĂ©itĂ©, lâĂ©paisseur et la composition des films minces. LâefficacitĂ© du procĂ©dĂ© dâauto-cicatrisation de ces matĂ©riaux a Ă©tĂ© mise en Ă©vidence in situ Ă 700°C par Microscopie Ălectronique Ă Balayage Environnementale Ă Haute TempĂ©rature (MEBE-HT).La tenue de ces revĂȘtements lors de cycles thermiques ainsi que les modifications structurales engendrĂ©es par la cristallisation du verre sous forme de couche mince ont Ă©galement Ă©tĂ© Ă©tudiĂ©es.Glassy thin films are promising candidates as protective coating for high temperature applications. However, due to thermal and/or mechanical stresses under operating conditions, these materials may crack. Previous studies have shown that self-healing glasses in bulk form can be prepared by incorporating active particles. These latter, when damages occur in the material, oxidize at high temperature to form oxides that flow into the crack and form a ânewâ glass by reaction with surrounding matrix.Based on these results, our work aimed at transposing this concept to glass materials deposited as thin layers, and so to envisage coating applications. We have shown the feasibility of forming these innovative coatings composed of alternating vitreous and healing agent layers. They have been prepared by Pulsed Laser Deposition (PLD) and Electron Beam-Physical Vapor Deposition (EB-PVD). A first part of our work was devoted to the optimization of the deposition parameters and their influence on homogeneity, thickness and composition of thin films. The efficiency of the self-healing process of these composite materials was demonstrated in situ at 700°C by High Temperature Environmental Scanning Electronic Microscopy (HT-ESEM). Finally, we studied the behavior of these coatings when they were submitted to thermal cycles as well as the structural changes generated by their crystallization
The dark side of soft tissues: unexpected inorganic carbonate in the invasive slipper limpet Crepidula fornicata and its implications for stable isotope interpretations
Rationale
Stable isotopic analysis is extensively used in trophic ecology. Inorganic carbonates, usually originating from shell fragments, are routinely removed from samples using an acid treatment because they affect ÎŽ13C values. However, acid treatment can also change ÎŽ15N values. For some taxa such as molluscs, the general assumption is that acid preâtreatment is not necessary since their shell is easily dissected from soft tissues and represents the only source of inorganic carbonates. However, other sources of nonâdietary carbon (e.g., intracellular inorganic carbon) enriched in 13C thus get overlooked.
Methods
Soft tissues (foot) of the invasive gastropod Crepidula fornicata of different size classes were analysed for their ÎŽ13C and ÎŽ15N values with and without acid preâtreatment using isotope ratio mass spectrometry. In toto microscopic investigations coupled with acid treatment, scanning electron microscopy and energy dispersive spectroscopy were used to highlight the presence of inorganic carbonate. A correction model was derived and applied to existing stable isotope data for C. fornicata. We used both seasonal variations in ÎŽ13C signatures and mixing model outputs to assess the error in ÎŽ13C values.
Results
Acid preâtreatment had a significant effect on the stable isotope compositions of C. fornicata foot tissue, especially on ÎŽ13C values: isotopic differences increased with size, up to 3â° for large females. No effect was detected for small (below ~20 mm) and motile males. In toto microscopic analysis revealed the presence of small spherules of inorganic carbonate, hence explaining the differences in ÎŽ13C values. Mixing model outputs and seasonal variation of ÎŽ13C values showed that untreated samples can lead to large misinterpretations about diet proportions and degree of trophic niche overlap, respectively.
Conclusions
Spherules of inorganic carbonate in C. fornicata soft tissues are likely to be linked with motility of this species and their mucus production. We recommend assessing the presence of inorganic carbonate in soft tissue of sessile gastropods
Thrombopénie et insuffisance rénale aiguë.
A 31-year old man is addressed to the emergency department for fever, abdominal pain and vomiting. Laboratory tests reveal an inflammatory syndrome, thrombocytopenia, acute kidney injury associated with major proteinuria (more than 3 g/24 h). Evaluation will conclude to an acute interstitial nephritis and the serology is positive for Hantavirus. This clinical case illustrates differential diagnosis of acute renal failure and reminds the theory of hemorrhagic fever with renal syndrome :usual clinical presentation is "flu"-like symptoms, thrombocytopenia and acute renal failure. Hantavirus is endemic in some area in Europe and in Belgium. This clinical presentation should suggest the diagnosis if the patient has stayed in an endemic area.Case ReportsEnglish AbstractJournal Articleinfo:eu-repo/semantics/publishe
A Salience Measure for 3D Shape Decomposition and Sub-parts Classification
International audienceThis paper introduces a measure of significance on a curve skeleton of a 3D piecewise linear shape mesh, allowing the computation of both the shape's parts and their saliency. We begin by reformulating three existing pruning measures into a non-linear PCA along the skeleton. From this PCA, we then derive a volume-based salience measure, the 3D WEDF, that determines the relative importance to the global shape of the shape part associated to a point of the skeleton. First, we provide robust algorithms for computing the 3D WEDF on a curve skeleton, independent on the number of skeleton branches. Then, we cluster the WEDF values to partition the curve skeleton, and coherently map the decomposition to the associated surface mesh. Thus, we develop an unsupervised hierarchical decomposition of the mesh faces into visually meaningful shape regions that are ordered according to their degree of perceptual salience. The shape analysis tools introduced in this paper are important for many applications including shape comparison, editing, and compression
Investigations of phosphate and silicate glasses and glass-ceramics deposited as nanometric thin films
International audienc
: From actimetry to activity, what are the contributions of the ergonomist to the design of a digital tool for measuring work?
International audienceThe collaboration with an industrial company presented here was intended to enrich the development of an actimetric tool, the subject of a thesis in computer science. This interdisciplinary research made it possible, beyond the knowledge transmitted on biomechanical stresses, to take into account its uses and acceptability from the design stage of the actimetric tool. The methodology of activity analysis was central to the conduct of the project.La collaboration avec un industriel prĂ©sentĂ©e ici, visait Ă enrichir le dĂ©veloppement dâun outil dâactimĂ©trie, sujet dâune thĂšse en informatique. Cette recherche interdisciplinaire a permis, au-delĂ des connaissances transmises sur les sollicitations biomĂ©caniques, de prendre en compte dĂšs la conception de lâoutil dâactimĂ©trie ses usages et son acceptabilitĂ©. La mĂ©thodologie dâanalyse de lâactivitĂ© a Ă©tĂ© centrale dans la conduite du projet
ThĂ©saurisation, Offrande, Recyclage et Echange de MĂ©taux Ă lâĂąge du Bronze en Languedoc : le projet ThĂ©OREM.
National audienc
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