Lanthanide Metal Ions as Cornerstones in Functional Self-Assembled Supramolecular Complexes

The peculiar spectroscopic, magnetic, and chemical properties of lanthanide ions (4f block, LnIII) are particularly attractive for the design of functional supramolecular devices if these ions can be selectively introduced into organized self-assembled architectures. The systematic investigation of a complete library of tridentate receptors leading to nine-coordinate tricapped trigonal prismatic sites upon coordination to LnIII allows the elucidation of the factors governing the structural, thermodynamic, electronic, magnetic, and spectroscopic properties of the final complexes. The simultaneous use of LnIII as cement between the molecular components of the supramolecular edifices and as functional vectors of the devices has been realized in self-assembled poly nuclear d-f and f-f complexes. Predetermined properties may result from a judicious molecular programming of the nanometric architecture leading to fascinating applications in luminescence, magnetism, template syntheses, and liquid crystals

Amenities and location of hotels: a micro-economic model and estimations.

Among different determinants, amenities play a major role in the location of tourism activities. In Tourism Economics, an extensive literature investigates the influence of amenities either on destination choice made by tourists or on economic development, generally at a regional or national level. This paper aims at analysing the influence of amenities on the location of hotels at local level. In a first part, after a presentation of the context of our work and a brief survey of existing literature on the link between amenities and tourism, we introduce and describe the different amenities features that will be analysed. In a second part, using a micro-economic model of hotel entry inspired by urban economics literature, we analyse the influence of amenities characteristics on a tourist bid-rent function and then on the number of hotels entering the market. The third part will be dedicated to an estimation of the effect of amenities on the creation of new hotels at the French 'Bassins de vie' level, which are functional economic areas

Activity of minocycline against Toxoplasma gondii infection in mice

The chemotherapeutic activity of minocycline, a semi-synthetic tetracycline analogue, was evaluated in a murine model of toxoplasmosis. A lethal acute toxoplas-mosis was produced by injecting 105 tachyzoites of the RH strain of Toxoplasma gondii into the peritoneal cavities of Swiss-Webster mice. When infected mice were treated once daily for 12 days, starting 2 h after challenge, the survival and cure rates were 100% and 40% respectively after minocycline alone (100 mg/kg per day), 0% and 0% after pyrimethamine alone (8.5 mg/kg per day), and 100% and 50% after combination of the two drugs at the same dosages. Absolute survival and cure with minocycline were observed when mice were treated with two daily doses of 100 mg/kg for 12 days. Mice chronically infected with a low virulent strain of T. gondii (Me49) showed a significant reduction in the number of brain cysts after three weeks of treatment with 50 mg/kg per day of minocycline. Minocycline serum levels after a single oral administration of 50 mg/kg or 100 mg/kg to normal mice, peaked at 1.8 mg/1 and 10 mg/1 after 1 h, respectively, and showed an extended half-lif

Evaluation of the efficacy of prolonged administration of azithromycin in a murine model of chronic toxoplasmosis

The efficacy of prolonged administration of azithromycin was evaluated in a murine model of lethal chronic toxoplasmosis. Mice were challenged intraperitoneally with cysts of a moderately virulent strain of Toxoplasma gondii, observed for 4 weeks and then allocated to the treatment or control group. All 26 animals given azithromycin 100 mg/kg/day for 100 days were protected compared with 19 of 25 control animals which died (P < 0.001). Nineteen of the 20 mice in the treatment group survived for an additional month while receiving the same azithriomycin regiment but viable cysts were indentified in the brain tissue of these animals when they were killed. Although there was no significant difference between the groups in terms of the number of cysts in the brain, the administration of azithromycin was associated with a reduction in brain inflammation. The concentrations of azithromycin in the brains of five animals ranged from 0.7 to 2.3 μ/g; there was no evidence of accumulation even after 100 doses. Azithromycin merits further evaluation as primary or secondary prophylaxis against toxoplasma encephalitis in individuals at risk of developing this complicatio

Apport de la mécanique des roches pour l'évaluation et la gestion des risques à long terme dans les exploitations minières abandonnées Cas des mines de fer de Lorraine

International audienceDue to its historical and economical evolution, we are now facing consequences of the end of mining in large sedimentary basins where it was the major regional activity during the last two Centuries. The contribution of Rock Mechanics in "after-mining" phases emerges nowadays, especially in the fields prediction and prevention of sudden collapses overlying partially mined areas. This paper present the example of closed iron mines in Lorraine (France) where different problems, at different scales have been identified : risk assessment, consequences for town-and-country planning and durable development.L'évolution historique et économique nous amène aujourd'hui à être confrontés aux conséquences de l'arrêt de l'exploitation de grands bassins miniers, qui a représenté l'activité dominante de certaines régions pendant un ou deux siècles. On commence à discerner ce que devra être aussi le rôle de la Mécanique des Roches pour la phase d'après-exploitation, notamment pour la prévision et la prévention des effondrements inopinés susceptibles de survenir lorsqu'ont été pratiquées des méthodes d'exploitation partielles. Le cas du bassin ferrifère lorrain, présenté dans cet article, illustre particulièrement bien les problèmes identifiés à différentes échelles : analyse et évaluation des risques, méthodes d'intervention avec les préoccupations d'un meilleur aménagement du territoire et d'un développement durable