La presse écrite en Ouzbékistan

Dans la conjoncture contemporaine de ré-agencement des nouveaux États indépendants d’Asie centrale, les domaines de compétence entre les diverses branches du pouvoir ne sont pas distinctement répartis et tendent à être éclipsés par la toute-puissance présidentielle. Les médias auraient pu représenter l’un des seuls contrepoids possibles puisque, dès la perestroïka, le “quatrième pouvoir” avait pris son autonomie face au politique et profité de la glasnost’ pour s’autonomiser et porter un rega..

Applications of liquid chromatography coupled to mass spectrometry-based metabolomics in clinical chemistry and toxicology: A review.

International audienceThe metabolome is the set of small molecular mass organic compounds found in a given biological media. It includes all organic substances naturally occurring from the metabolism of the studied living organism, except biological polymers, but also xenobiotics and their biotransformation products. The metabolic fingerprints of biofluids obtained by mass spectrometry (MS) or nuclear magnetic resonance (NMR)-based methods contain a few hundreds to thousands of signals related to both genetic and environmental contributions. Metabolomics, which refers to the untargeted quantitative or semi-quantitative analysis of the metabolome, is a promising tool for biomarker discovery. Although proof-of-concept studies by metabolomics-based approaches in the field of toxicology and clinical chemistry have initially been performed using NMR, the use of liquid chromatography hyphenated to mass spectrometry (LC/MS) has increased over the recent years, providing complementary results to those obtained with other approaches. This paper reviews and comments the input of LC/MS in this field. We describe here the overall process of analysis, review some seminal papers in the field and discuss the perspectives of metabolomics for the biomonitoring of exposure and diagnosis of diseases

An extremal model for amorphous media plasticity

An extremal model for the plasticity of amorphous materials is studied in a simple two-dimensional anti-plane geometry. The steady-state is analyzed through numerical simulations. Long-range spatial and temporal correlations in local slip events are shown to develop, leading to non-trivial and highly anisotropic scaling laws. In particular, the plastic strain is shown to statistically concentrate over a region which tends to align perpendicular to the displacement gradient. By construction, the model can be seen as giving rise to a depinning transition, the threshold of which (i.e. the macroscopic yield stress) also reveal scaling properties reflecting the localization of the activity.Comment: 4 pages, 5 figure

Characterization of the microbiome associated with in situ earthen materials

Background The current increase in public awareness of environmental risks is giving rise to a growth of interest in the microbiological safety of buildings. In particular, microbial proliferation on construction materials can be responsible for the degradation of indoor air quality that can increase health-risk to occupants. Raw earth materials are still widely used throughout the world and, in some cases, are linked to heritage habitats, as in the southwest of France. Moreover, these building materials are currently the subject of renewed interest for ecological and economic reasons. However, the microbial status of earthen materials raises major concerns: could the microbiome associated with such natural materials cause disease in building occupants? Very few analyses have been performed on the microbial communities present on these supports. Characterizing the raw earth material microbiome is also important for a better evaluation and understanding of the susceptibility of such materials to microbial development. This study presents the distribution of in situ bacterial and fungal communities on different raw earth materials used in construction. Various buildings were sampled in France and the microbial communities present were characterized by amplicon high-throughput sequencing (bacterial 16S rRNA gene and fungal ITS1 region). Bacterial culture isolates were identified at the species level by MALDI-TOF mass spectrometry. Results The major fungal and bacterial genera identified were mainly associated with conventional outdoor and indoor environmental communities, and no specific harmful bacterial species were detected on earthen materials. However, contrary to expectations, few human-associated genera were detected in dwellings. We found lower microbial alpha-diversity in earthen material than is usually found in soil, suggesting a loss of diversity during the use of these materials in buildings. Interestingly enough, the main features influencing microbial communities were building history and room use, rather than material composition. Conclusions These results constitute a first in-depth analysis of microbial communities present on earthen materials in situ and may be considered as a first referential to investigate microbial communities on such materials according to environmental conditions and their potential health impact. The bacterial and fungal flora detected were similar to those found in conventional habitats and are thought to be mainly impacted by specific events in the building’s life, such as water damage

Development of an electrospray-mass spectral database for annotating metabolomics datasets: application to the analysis of the adult human urinary metabolome

Metabolomics opens new perspectives for biomarker discovery in the field of nutrition and heath, and also in the development of system biology. The metabolic profiles of biofluids obtained by mass spectrometry or nuclear magnetic resonance contain a few hundreds to thousands of signals. However, a major part of this information remains unknown, or at least not characterized in the analytical systems, thus hampering the obtention of biologically meaningfull data. In this context, we here report on the development of an electrospray (ESI) spectral database for the annotation of high resolution mass spectrometry based metabolomics data sets and on its application to the analysis of urine samples from a cohort of healthy volunteers

Une stabilisation efficace de l'élément fini P1/P1 en grandes transformations

L'objectif de ce travail est de proposer un stabilisation robuste de l'élément fini P1/P1 en grandes transformations. La première partie est consacrée à l'étude des propriétés de l'élément fini P1/P1 connu pour ne pas être LBB-stable. Ensuite, une nouvelle formulation stabilisée simple et robuste est proposée afin d'éviter les modes de pression parasites pour l'analyse de structures métalliques élasto-plastiques ou élasto-viscoplastiques. Enfin, des exemples sont présentés pour illustrer l'efficacité de l'approche développée