Assessment of exposure to air pollution from road traffic: use of air dispersion model CALINE4 at a fine scale in Cracow

This article deals with the road traffic air pollution modeling which is also part of a main multidisciplinary study of health risk characterization untitled: "Air pollution generated by road traffic and childhood asthma in Cracow". Cracow, a city declared as a UNESCO World Heritage Site, constitutes a relevant urban area to study insofar road traffic as a strong anthropogenic source of air pollution. The final aim of the health study is to establish in Cracow the relationship between air quality and the development of asthma among children. We have chosen the air dispersion model CALINE4 and its software interface, CALROADS VIEW, to estimate the PM10 and NO2 concentrations generated by road traffic at 43 key intersections in Cracow during the period 2001-2005. This model is recognized as an international reference in road traffic air pollution modeling. The concentration of traffic and trips in the historical downtown area and the importance of exchanges between the two downtowns of Cracow (historical downtown and Nowa Huta) are the main causes of high air pollution levels from road traffic. Depending on the pollutant considered (PM10, NO2) as well as the density of traffic and the meteorological situations, areas of exposure to air pollution and their potential health effects to the exposed population are quite different in time and in space. The main results show that: 1) Only the NO2 exposure areas reach the residential areas because the PM10 areas of exposure (Avg: 66.8 m SD: ą 48.5, max: 284 m) are quite less extensive than those of NO2 (Avg: 125.4 SD: ą 64.4, max: 381 m); 2) Extension of these two pollutant areas is proportionally related to the density of traffic and is extended in an unsymmetrical way around roads depending on meteorological cases determined by both the Pasquill-Gifford classification and the wind directions. According to our methodology, the validation of estimated PM10 and NO2 concentrations shows that they have been overwhelmingly validated

A combinatorial algorithm for microbial consortia synthetic design

International audienceSynthetic biology has boomed since the early 2000s when it started being shown that it was possible to efficiently synthetize compounds of interest in a much more rapid and effective way by using other organisms than those naturally producing them. However, to thus engineer a single organism, often a microbe, to optimise one or a collection of metabolic tasks may lead to difficulties when attempting to obtain a production system that is efficient, or to avoid toxic effects for the recruited microorganism. The idea of using instead a microbial consortium has thus started being developed in the last decade. This was motivated by the fact that such consortia may perform more complicated functions than could single populations and be more robust to environmental fluctuations. Success is however not always guaranteed. In particular, establishing which consortium is best for the production of a given compound or set thereof remains a great challenge. This is the problem we address in this paper. We thus introduce an initial model and a method that enable to propose a consortium to synthetically produce compounds that are either exogenous to it, or are endogenous but where interaction among the species in the consortium could improve the production line. Synthetic biology has been defined by the European Commission as " the application of science, technology, and engineering to facilitate and accelerate the design, manufacture, and/or modification of genetic materials in living organisms to alter living or nonliving materials ". It is a field that has boomed since the early 2000s when in particular Jay Keasling showed that it was possible to efficiently synthetise a compound–artemisinic acid–which after a few more tricks then leads to an effective anti-malaria drug, artemisini

BacHBerry: BACterial Hosts for production of Bioactive phenolics from bERRY fruits

BACterial Hosts for production of Bioactive phenolics from bERRY fruits (BacHBerry) was a 3-year project funded by the Seventh Framework Programme (FP7) of the European Union that ran between November 2013 and October 2016. The overall aim of the project was to establish a sustainable and economically-feasible strategy for the production of novel high-value phenolic compounds isolated from berry fruits using bacterial platforms. The project aimed at covering all stages of the discovery and pre-commercialization process, including berry collection, screening and characterization of their bioactive components, identification and functional characterization of the corresponding biosynthetic pathways, and construction of Gram-positive bacterial cell factories producing phenolic compounds. Further activities included optimization of polyphenol extraction methods from bacterial cultures, scale-up of production by fermentation up to pilot scale, as well as societal and economic analyses of the processes. This review article summarizes some of the key findings obtained throughout the duration of the project

Organisation du peuplement de marsupiaux en Guyane Française

The structure of the marsupial communities was investigated from 1984 to 1987 in different forest types of French Guiana. The mature forest community of the Piste de Saint-Elie (PSE) study site was studied at regular intervals for 22 months by direct observation and trapping, allowing a detailed comparison to be made with the Cabassou (Cab) secondary forest community previously studied by P. Charles-Dominique et al. (1981), and with other sites less thoroughly investigated. Nine marsupial species (Didelphidae) coexist in the PSE mature forest, ranging in weight from 20 to 1 100 g. All share the habitat, both vertically (ground level, understorey and/or canopy) and horizontally (well drained vs. hydromor- phic soils, watercourses) (Tables II, III). The eight terrestrial and arboreal species are found in pairs, in which both species are morphologically and ecologically comparable, but one is common and the other is rare (Table VII). Population densities appear to be low, even for the most abundant species. In contrast, species richness is lower in secondary forest (six species at Cabassou), and the density of the most common species is higher. Only one species pair is remaining, through the disappearance of most rare species. A review of the scanty data available for French Guiana, and of those scattered in the literature, suggests that those marsupial species which are rare and found only in mature forest are habitat specialists, whereas the second-growth species are habitat generalists. However, such a tentative conclusion needs to be supported by further field work. Didelphis albiventris is reported for the first time from French Guiana (PSE).Julien-laferriere Didier. Organisation du peuplement de marsupiaux en Guyane Française. In: Revue d'Écologie (La Terre et La Vie), tome 46, n°2, 1991. pp. 125-144

Modéliser le métabolisme : Expliciter les réponses aux perturbations et composer des consortia microbiens

In this PhD work, we proposed to model metabolism. Our focus was to develop generic models, that are not specific to one organism or condition, but are instead based on general assumptions that we tried to validate using data from the literature.We first present TOTORO that uses a qualitative measurement of concentrations in two steady-states to infer the reaction changes that lead to differences in metabolite pools in both conditions.TOTORO enumerates all sub-(hyper)graphs that represent a sufficient explanation for the observed differences in concentrations. We exploit a dataset of Yeast (Saccharomyces cerevisiae) exposed to cadmium and show that we manage to retrieve the known pathways used by the organisms. We then address the same issue, but using a constraint-based programming framework, called KOTOURA, that allows to infer more quantitatively the reaction changes during the perturbed state. We use in this case exact concentration measurements and the stoichiometric matrix, and show on simulated datasets that the overall variations of reaction fluxes can be captured by our formulation.Finally, we propose MULTIPUS, a method to infer microbial communities and metabolic roads to produce specific target compounds from a set of defined substrates. We use in this case a weighted directed hypergraph. We apply MULTIPUS to the production of antibiotics using a consortium composed of an archae and an actinobacteria and show hat their metabolic capacities are complementary. We then infer for another community the excretion of an inhibitory product (acetate) by a 1,3-propanediol (PDO) producer and its consumption by a methanogene archaeLors de cette thèse, je me suis intéressée à la modélisation du métabolisme des micro-organismes. Nous nous sommes focalisé sur le métabolisme des petites molécules qui ne prend pas en compte les réactions associées aux macromolécules, telle que la synthèse des protéines.Nous avons ainsi utilisé différents formalismes de modélisation.Tout d'abord, nous avons développé TOTORO où les réseaux métaboliques sont représentés par des hypergraphes dirigés et qui permet d'identifier les réactions ayant participé à une transition métabolique. TOTORO a été utilisé sur un jeu de données sur la levure en présence de cadmium. Nous avons pu montrer que nous retrouvons les mécanismes connus de désintoxication.Ensuite, en utilisant une méthode de modélisation par contraintes, nous discutons d'un développement en cours, KOTOURA, qui propose d'utiliser les connaissances actuelles de concentrations de métabolites entre différentes conditions pour inférer de manière quantitative les possibles asynchronies des réactions lors du passage d'un état stable à un autre. Nous avons testé son implémentation sur des données simulées.Enfin, nous proposons MULTIPUS, une méthode d'extraction d'(hyper)-arbres de Steiner dirigés qui permet de sélectionner les voies métaboliques pour la production de composés au sein d'une communauté bactérienne. Les réseaux métaboliques sont modélisés en utilisant des hypergraphes dirigés et pondérés. Nous proposons un algorithme de programmation dynamique paramétré ainsi qu'une formulation utilisant la programmation par ensemble réponse. Ces deux propositions sont ensuite comparées dans deux cas d'application

Place du Médecin traitant dans le suivi de patients atteints par le VIH

TOURS-BU Médecine (372612103) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF