De la capacité d'une bouche artificielle a reproduire le geste d'un instrumentiste

National audienceCe travail présente une étude sur la capacité d'une bouche artificielle aspirante à reproduire le jeu d'une clarinette simplifiée. Le système étudié est composé d'un bec instrumenté connecté à un cylindre. L'instrument est joué d'une part par un musicien, d'autre part à l'aide de la bouche artificielle aspirante. Le bec permet la mesure de la pression dans la bouche du musicien, la pression acoustique dans le bec et le déplacement de l'extrémité de l'anche. Le geste instrumental est caractérisé par les paramètres de jeu et les paramètres d'anche estimés par l'analyse de la partie stationnaire des signaux mesurés. Les paramètres de jeu considérés dans ce travail sont la pression moyenne dans la bouche et la valeur maximale du déplacement de l'anche. Les paramètres d'anche estimés à l'aide d'une méthode inverse sont la raideur non linéaire, l'amortissement équivalent de l'anche et l'ouverture au repos. La bouche artificielle est réglée de façon à obtenir des valeurs de paramètres de jeu proches de ceux obtenus avec un musicien pour une nuance et une embouchure données. L'analyse et la comparaison d'un jeu de paramètres d'anche permet de quantifier la performance de la bouche artificielle à reproduire une situation de jeu. La gamme de fonctionnement de la bouche artificielle est ainsi définie pour pouvoir étudier à terme les caractéristiques d'anches considérées comme différentes

Bio-based substances from urban waste as auxiliaries for solar photo-Fenton treatment under mild conditions: Optimization of operational variables

The use of soluble bio-based organic substances (SBO) obtained from urban wastes to expand the pH region where the photo-Fenton process can be applied has been investigated in this study. For this purpose, a mixture of six pollutants, namely acetaminophen, carbamazepine, amoxicillin, acetamiprid, clofibric acid and caffeine, at an initial concentration of 5 mg L-1 each, has been employed. Surface response methodology, based on the Doehlert matrix, has shown to be a useful tool to determine the effect of pH (in the range 3-7), concentration of SBO (15-25 mg L-1) and iron (2-6 mg L-1) on the performance of the photodegradation of the studied pollutants, measured by their half-life. Results indicate that, at high SBO concentration, the optimum pH shifts in most cases to a higher value (between 3 and 4) and that a significant loss of efficiency of the process was only observed at pH values above 5. An iron concentration of 4-5 mg L-1 and an amount of SBO of 19-22 mg L-1 have been determined to be the optimal conditions for the degradation of most of the studied pollutants at pH = 5. (C) 2014 Elsevier B.V. All rights reserved.The authors want to thank the financial support of the European Union (PIRSES-GA-2010-269128, EnvironBOS) and Spanish Ministerio de Educacion y Ciencia (CTQ2012-38754-C03-02). Juan Gomis would like to thank UPV for his FPI grant (2010-07).Gomis Vicens, J.; Carlos, L.; Bianco Prevot, A.; Teixeira, ACSC.; Mora Carbonell, M.; Amat Payá, AM.; Vicente Candela, R.... (2015). Bio-based substances from urban waste as auxiliaries for solar photo-Fenton treatment under mild conditions: Optimization of operational variables. Catalysis Today. 240(Part A):39-45. https://doi.org/10.1016/j.cattod.2014.03.034S3945240Part

Discovery and validation of a three-gene signature to distinguish COVID-19 and other viral infections in emergency infectious disease presentations: a case-control and observational cohort study

Summary Background Emergency admissions for infection often lack initial diagnostic certainty. COVID-19 has highlighted a need for novel diagnostic approaches to indicate likelihood of viral infection in a pandemic setting. We aimed to derive and validate a blood transcriptional signature to detect viral infections, including COVID-19, among adults with suspected infection who presented to the emergency department. Methods Individuals (aged ≥18 years) presenting with suspected infection to an emergency department at a major teaching hospital in the UK were prospectively recruited as part of the Bioresource in Adult Infectious Diseases (BioAID) discovery cohort. Whole-blood RNA sequencing was done on samples from participants with subsequently confirmed viral, bacterial, or no infection diagnoses. Differentially expressed host genes that met additional filtering criteria were subjected to feature selection to derive the most parsimonious discriminating signature. We validated the signature via RT-qPCR in a prospective validation cohort of participants who presented to an emergency department with undifferentiated fever, and a second case-control validation cohort of emergency department participants with PCR-positive COVID-19 or bacterial infection. We assessed signature performance by calculating the area under receiver operating characteristic curves (AUROCs), sensitivities, and specificities. Findings A three-gene transcript signature, comprising HERC6, IGF1R, and NAGK, was derived from the discovery cohort of 56 participants with bacterial infections and 27 with viral infections. In the validation cohort of 200 participants, the signature differentiated bacterial from viral infections with an AUROC of 0·976 (95% CI 0·919−1·000), sensitivity of 97·3% (85·8−99·9), and specificity of 100% (63·1−100). The AUROC for C-reactive protein (CRP) was 0·833 (0·694−0·944) and for leukocyte count was 0·938 (0·840−0·986). The signature achieved higher net benefit in decision curve analysis than either CRP or leukocyte count for discriminating viral infections from all other infections. In the second validation analysis, which included SARS-CoV-2-positive participants, the signature discriminated 35 bacterial infections from 34 SARS-CoV-2-positive COVID-19 infections with AUROC of 0·953 (0·893−0·992), sensitivity 88·6%, and specificity of 94·1%. Interpretation This novel three-gene signature discriminates viral infections, including COVID-19, from other emergency infection presentations in adults, outperforming both leukocyte count and CRP, thus potentially providing substantial clinical utility in managing acute presentations with infection. Funding National Institute for Health Research, Medical Research Council, Wellcome Trust, and EU-FP7

A review on the toxicology and dietetic role of bacterial cellulose

Bacterial cellulose (BC) is a biopolymer synthesized by certain acetic acid bacteria strains. The safety of BC regarding its potential use in food applications is here reviewed. The acute, sub-acute and subchronic oral toxicity assays showed that consumption of BC had no adverse effects in rats. Several studies demonstrated that BC is not genotoxic, did not induce chromosomal aberrations in CHO cells under both non-activating and metabolic activating conditions, is inactive in the in vitro Rat Primary Hepatocyte Unscheduled DNA Synthesis Assay, had no reproductive toxicity in mice and exerted no embryotoxicity and teratogenicity effects in rats. Several studies on the BC in biomedical applications further reinforces its safety: a primary eye and dermal irritation studies in the rabbit showed that BC was non-irritating. The inflammatory reaction to subcutaneously implanted BC has been evaluated in animal models and for different periods of time, demonstrating that BC is biocompatible and does not trigger a harsh inflammatory reaction. Altogether, and considering its longstanding history of human consumption in Asian countries, as well as its utilization in biomedical devices, it may be concluded that BC is safe for applications in food technology.FCT -Fuel Cell Technologies Program(NORTE-01-0145-FEDER-000004)info:eu-repo/semantics/publishedVersio