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Climate change has been linked with the establishment and geographical expansion of zoonotic diseases, an example of which is the well-documented increase in human cases of Lyme disease in Quebec, Canada. As temperatures continue to increase in Quebec, it is anticipated that several zoonotic diseases will be affected. In response to the growing zoonotic issues facing public health authorities, Quebec's Multi-Party Observatory on Zoonoses and Adaptation to Climate Change (Observatoire multipartite québécois sur les zoonoses et l'adaptation aux changements climatiques) (the Observatory) was founded in 2015 as part of the Quebec government's Climate Change Action Plan (Plan d'action 2013-2020 sur les changements climatiques). The Observatory was designed to bring together agencies involved in formulating public policy and experts from the disciplines of human health, animal health and environmental sciences, in a manner similar to the innovative "One World, One Health" approach. The Observatory provides a platform for knowledge sharing and consensus building among representatives of public policy decision makers and scientists. Its main objectives are to anticipate and prioritize potential issues associated with zoonotic diseases in Quebec, in order to support applicable risk management and climate change adaptation. This article describes what the Observatory is, what it does and outlines its plans for the future.
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Titanium(IV) oxide thin films have been prepared by dip-coating at ambient temperature from a TiO2 colloidal suspension. Prior to deposition, this suspension was synthesized by microwave-induced thermal hydrolysis of a titanium tetrachloride aqueous solution in the presence of hydrochloric acid. The effects, on film roughness and film thickness, of substrate, number of layers, substrate withdrawal speed, and heat treatment temperature were investigated on different observation scales. The microwave-born oxide nanoparticles showed good affinity to glass and silicon substrates; 10- to 50-nm-thick thin films, with absorption edge blue-shifted compared to bulk anatase, were obtained through a simple process without the need of heating treatment for crystallization purposes.
RESUMO
Tin(IV) oxide thin films have been prepared by dip-coating. The suspensions used for these depositions have been synthesized by microwave-induced thermohydrolysis of tin tetrachloride aqueous solutions in the presence of hydrochloric acid. Single or multiple depositions were tested, on glass substrates as well as on pure SiO2. The obtained thin films were characterized by optical microscopy, interferometric roughness measurements (Micromap), scanning electron microscopy, secondary ion mass spectroscopy, and scanning tunneling microscopy.
Assuntos
Coloides/síntese química , Micro-Ondas , Compostos de Estanho/química , Coloides/química , Vidro/química , Ácido Clorídrico/química , Hidrólise , Microscopia Eletrônica de Varredura , Microscopia de Interferência , Microscopia de Tunelamento , Tamanho da Partícula , Dióxido de Silício/química , Espectrometria de Massa de Íon Secundário , Análise Espectral , Propriedades de SuperfícieRESUMO
The growth of the hydrocarbon-rich alga Botryococcus braunii was studied under "air-lift" conditions using batch and continuous cultures. Large variations in the physiological state of B. braunii were achieved in batch cultures and in continuous cultures with various dilution rates. The possible effects of these variations upon hydrocarbons (nature, relative abundance, location, level, productivity) and also on the production of exocellular polysaccharides were examined. The relationships between the physiological state of B. braunii and its hydrocarbon and polysaccharide production were discussed and compared with those generally observed in unicellular algae. The factors giving rise to the transition from high to low productivity stages were considered. To this end we examined, at first, the variations in cell ultrastructure and the resulting degeneration occurring during batch cultures. Afterward the parallel changes in some parameters of the medium (pH, phosphate level) were determined and their possible relationships with B. braunii growth and hydrocarbon production were discussed. The main features of phosphate nutrition in B. braunii and its effects on hydrocarbons were finally examined.