Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
An inter-laboratory exercise was organized under the PHARMAS EU project, by the Advanced School of Public Health (EHESP), in order to evaluate the performances of analytical methods for the measurement of antibiotics in waters (surface and tap). This is the first time such an exercise on antibiotics has been organized in Europe, using different kinds of analytical methods and devices. In this exercise thirteen laboratories from five countries (Canada, France, Italy, the Netherlands and Portugal) participated, and a total number of 78 samples were distributed. During the exercise, 2 testing samples (3 bottles of each) prepared from tap water and river water, respectively, spiked with antibiotics, were sent to participants and analyzed over a period of one month. A final number of 77 (98.7%) testing samples were considered. Depending on substances studied by each participant, 305 values in duplicate were collected, with the results for each sample being expressed as the target concentration. A statistical study was initiated using 611 results. The mean value, standard deviation, coefficient of variation, standard uncertainty of the mean, median, the minimum and maximum values of each series as well as the 95% confidence interval were obtained from each participant laboratory. In this exercise, 36 results (6% of accounted values) were outliers according to the distribution over the median (box plot). The outlier results were excluded. In order to establish the stability of testing samples in the course of the exercise, differences between variances obtained for every type of sample at different intervals were evaluated. The results showed no representative variations and it can be considered that all samples were stable during the exercise. The goals of this inter-laboratory study were to assess results variability when analysis is conducted by different laboratories, to evaluate the influence of different matrix samples, and to determine the rate at which participating laboratories successfully completed the tests initiated.
Talanta

hal-00878118
https://hal.archives-ouvertes.fr/hal-00878118
DOI : 10.1016/j.talanta.2012.06.064
PUBMED : 22939142

Éditeur(s) : HAL CCSD Oxford University Press
Résumé : International audience
Chronic rhinosinusitis (CRS) rank second at chronic inflammatory diseases in industrialized countries and are an important public health concern. Diagnosis relies on a set of arguments including clinical signs, imaging, histopathologic and mycological analyses of sinus specimens, collected during nasal endoscopy. The sensitivity of fungal cultures is reported to be poor, even when direct examination is positive, thus the epidemiology of fungal chronic sinusitis is ill-known. This study evaluated the sensitivity of molecular diagnosis in 70 consecutive samples (61 patients with CRS) analysed at the University Hospital of Rennes during a 3-year period. DNA detection was performed using a conventional PCR method targeting the ITS1/ITS2 sequence and the resulting amplification products were sequenced. Fungal CRS was proven in 42 patients (69%), of which only 20 (48%) had a positive culture. 37/42 (88%) patients were diagnosed with a fungus ball, 3 with allergic fungal CRS and 2 with undetermined fungal CRS. PCR was positive in all 42 cases and direct sequencing allowed to identify fungi in all cases but one, and detected multiple infection in 3. Aspergillus fumigatus was present in 69% of patients; Cladosporium cladosporoides in 9.5%, Scedosporium sp., A. nidulans and A. flavus in 7% each. In 2/19 patients with negative direct examination, sequencing analysis revealed the presence of Capnobotryella sp. and C. cladosporoides, in clinical settings compatible with fungal sinusitis. In conclusion, ITS1/ITS2 PCR had a twice better sensitivity than culture, and combined sequencing provides accurate epidemiological data on fungal CRS.
ISSN: 1369-3786

hal-01383632
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01383632
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01383632/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01383632/file/Contribution%20of%20molecular%20tools%20for%20the%20diagnosis.pdf
DOI : 10.1093/mmy/myw041

Éditeur(s) : HAL CCSD American Geophysical Union
Résumé : International audience
Torsion experiments (inline image =3 × 10−4 s−1) were performed to investigate the large strain (γmax = 15) rheology on quartz-muscovite aggregate as analogue to pelitic rocks undergoing melting and crystallization during deformation at 300 MPa confining pressure and 750°C temperature. Microstructures reveal four distinct but gradational stages of crystal-melt interactions during deformation--(a) solid state deformation, (b) initiation and domination of partial melting, (c) simultaneous partial melting and crystallization, and (d) domination of crystallization. The microstructural stages are linked to the rheology of the deforming samples. Partial melting starts at relatively low finite shear strains (γ = 1-3) showing approximately 60% strain softening. At γ = 4-10 the partially molten bulk material shows a steady state flow at low stress. Further crystallization of new crystals at the expense of melt between γ = 10 and 15 causes weak strain hardening until the material fails by developing brittle fractures. The stress exponent (n), calculated at γ = 1, 5, and 10, increases from ∼ 3 to ∼ 43, indicating a transition from power to power law breakdown or exponential flow of the bulk system. Hydrostatic experiments for equivalent times and conditions of the torsion experiments were also conducted to evaluate the reaction kinetics and microstructures under static conditions. The new experimental data establish that partially molten rock does not flow according to a constant strain rate-dependent power law (steady state) rheology. The rheological transition from strain rate sensitive to strain rate insensitive flow is interpreted as a function of melt-crystal ratio, their mutual interactions, and the evolution of microstructures in the partially molten rock.
ISSN: 0148-0227

hal-01053709
https://hal.archives-ouvertes.fr/hal-01053709
DOI : 10.1002/2013JB010777

Éditeur(s) : [S.l.] : Harper
Siècle(s) traité(s) : 19
Droits : Domaine public
Provenance : Université des Antilles. Service commun de la documentation
Permalien : http://www.manioc.org/patrimon/HASH40423832e7422746ff4d15
HASH40423832e7422746ff4d15