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Background: Chikungunya fever is a viral disease that recently invaded the American continent. In America, it is transmitted mainly by the mosquito Aedes aegypti, but Aedes albopictus is the main vector in other regions of the world. This work estimates the risk of disease emergence and the corresponding population at risk for the case of a naive population in the metropolitan area of Buenos Aires, the capital city of Argentina.Methods: A classic metapopulation epidemiological model, that considers human and mosquito populations, was extended in order to include different environmental signals. First, the vital rates of the mosquitoes were affected by local temperature. Second, habitat availability estimated from satellite images was used to determine the carrying capacity for local mosquito populations. Disease invasion was proposed to occur at different moments of the year. For each scenario, Monte Carlo simulations were used to estimate the risk of disease invasion and the population at risk.Results: The risk of a Chikungunya outbreak displays strong temporal (seasonal) patterns as well as spatial variability at the level of neighborhoods in the study area. According to the model, Summer and Fall display high risk for a Chikungunya invasion. The population at risk displays less variation over the year underlying the importance of preventive actions.Conclusions: The ability of mapping habitat quality for vector-borne diseases allows developing risk analysis at scales that are easily manageable for public health officers. For this location, the correlation of disease risk with the season of the year and the habitat availability could provide information to develop efficient control strategies. This also underlines the importance of involving the whole community when developing control measures for Chikungunya fever and other recently invading vector-borne diseases such as Zika fever. [ABSTRACT FROM AUTHOR]

The purpose of this work is to assess the impact on the Esteros del Ibera wetland ecosystem caused by the Yacyreta dam, a large hydroelectric power plant on the Parana River, Argentina, in comparison to other factors of environmental change. The project of the dam started around 1970. The power plant began operating in 1994. In 1989, the neighboring Ibera wetland ecosystem showed a substantial increase in the water level for which several different causes were conceivable, including climate change and the dam construction. We analyzed all existing hydrometeorological data and studied other changes that were observed in this ecosystem. A water balance model was used to analyze different scenarios. Increased groundwater inflow, generated since the construction of the dam, appears to be affecting the wetland more than any other factor. The study has implications for the assessment of global and regional consequences of building dams. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this work is to analyze at a regional scale the hydrometeorological and hydrological characteristics of the Esteros del Ibera, a vast freshwater wetland located in NE Argentina. Since water is the main driving force in the inland wetlands and variations in water level impose conditions on the behavior of vegetation and animal populations, the knowledge of the main hydrometeorological variables that affect the hydrology is essential. Data correlation analysis makes it possible to evaluate the observed changes in the wetland and to infer its response to regional climatic change. As a first approach, the construction of a topo-bathymetric map provides a basic tool for developing a digital elevation model (DEM) using a geographic information system (GIS) and models that are based on a spatial scale. [Copyright &y& Elsevier]

To select and establish floral biomarkers of the botanical origin of Diplotaxis tenuifolia honeys, the flavonoids and glucosinolates present in bee-deposited nectar collected from hive combs (unripe honey) and mature honey from the same hives fron which the unripe honey samples were collected were analyzed by LC-UV-PAD-ESI-MS(n). Glycosidic conjugates of the flavonols quercetin, kaempferol, and isorhamnetin were detected and characterized in unripe honey. D. tenuifolia mature honeys contained the aglycones kaempferol, quercetin, and isorhamnetin. The differences between the phenolic profiles of mature honey and freshly deposited honey could be due to hydrolytic enzymatic activities. Aliphatic and indole glucososinolates were analyzed in unripe and mature honeys, this being the first report of the detection and characterization of glucosinolates as honey constituents. Moreover, these honey samples contained different amounts of propolis-derived flavonoid aglycones (1765-3171 μg/100 g) and hydroxycinnamic acid derivatives (29-1514 μg/100 g). Propolis flavonoids were already present in the freshly deposited nectar, showing that the incorporation of these compounds to honey occurs at the early steps of honey production. The flavonoids quercetin, kaempferol, and isorhamnetin and the glucosinolates detected in the samples could be used as complementary biomarkers for the determination of the floral origin of Argentinean Diplotaxis honeys.