544 research outputs found
The antica Fonte of Boario (Italy): An hydrochemical and isotopic investigation in support of mineral water development
The "Antica Fonte" mineral water is a valuable resource with well-known therapeutic effects due to its high magnesium and sulphate contents. Hydrochemical and isotopic data indicate that the water is recharged at an elevation exceeding 1000 m asl, derives its mineral content by dissolution of Triassic gypsum and dolomite, and partially mixes with present day recharge from the alluvial aquifer. The results of this investigation provide valuable information for a sustainable development of the resource
Same or different – that is the question: identification of crystal forms from crystal structure data
Hydrochemical and Isotopic Features of the Khaung Daing Hot Spring (Inle lake, Southern Shan State, Myanmar)
Abstract The Inle lake watershed develops along a right-lateral strike-slip fault running parallel to the Sangaing fault, a major continental transform fault between the India and Sunda Plates. Located on the northwestern border of the Inle lake basin, the Khaung Daing hot spring outflows at a temperature of about 70C. This contribution represents a reconnaissance study of the spring and describes its main hydrochemical and isotopic features, compared to surface and ground waters in the watershed. The water pH is slightly acidic, and, compared to the other water samples from the watershed, shows an EC in the high range (57-1284μS/cm), the lowest pH and Eh values, and is Na-HCO 3 , whereas surface and ground waters are Ca(Mg)-HCO 3 type. The hot spring isotopic composition falls close to the Yangon Meteoric Water Line, indicating that, despite its temperature, it is not strongly modified by water-rock interaction processes. Preliminary results suggest that this hydrothermal water is likely related to deep meteoric and ground water circulation within a fault zone, in a region characterized by an elevated geothermal gradient
Squaring the cycle: the integration of groundwater processes in nutrient budgets for a basin-oriented remediation strategy
Contamination, surface and ground waters, sink, mass balances
Integrated socio-hydrogeological approach to tackle nitrate contamination in groundwater resources. The case of Grombalia Basin (Tunisia)
Nitrate contamination still remains one of the main groundwater quality issues in several aquifers worldwide, despite the perduring efforts of the international scientific community to effectively tackle this problem. The classical hydrogeological and isotopic investigations are obviously of paramount importance for the characterization of contaminant sources, but are clearly not sufficient for the correct and long-term protection of groundwater resources. This paper aims at demonstrating the effectiveness of the socio-hydrogeological approach as the best tool to tackle groundwater quality issues, while contributing bridging the gap between science and society. An integrated survey, including land use, hydrochemical (physicochemical parameters and major ions) and isotopic (delta N-15(No3) and delta O-18(No3)) analyses, coupled to capacity building and participatory activities was carried out to correctly attribute the nitrate origin in groundwater from the Grombalia Basin (North Tunisia), a region where only synthetic fertilizers have been generally identified as the main source of such pollution. Results demonstrates that the basin is characterized by high nitrate concentrations, often exceeding the statutory limits for drinking water, in both the shallow and deep aquifers, whereas sources are associated to both agricultural and urban activities
Potentially Toxic Elements (PTEs) in Cultivated Soils from Lombardy (Northern Italy): Spatial Distribution, Origin, and Management Implications
This work aims to quantify the contribution of agricultural practices to diffuse pollution in cultivated soils. Two samples (the first from the top layer and the second from a depth of about 100 cm) were retrieved from about 1000 soil profiles and analyzed for their potentially toxic elements (PTEs) content (Cd, Cu, Ni, Pb, Zn, Mn). In addition, we collected dedicated soil profiles for three specific types of land use and agronomic practice, namely vine-, cereal- and rice-growing areas. Baseline concentrations and distribution maps were produced. Statistical data treatment, coupled with the results of the dedicated soil profiles, enabled the identification of precise pollution sources and processes. In cultivated soils, PTEs contents prove to be generally well below the Italian regulatory limits, with the exception of Cu in vineyard soils, due to the long-lasting use of Cu-based pesticides. South of Milan and in other urban areas, we attribute the top soil enrichment in Cd, Cu, Pb, and Zn to industrial activities and urban settlement. Ni sporadically exceeds regulatory standards, but its association with Mn and its depth distribution point to a natural origin, mostly due to the occurrence of serpentine. The project demonstrates that although agriculture, especially in the form of vineyards and of intensive cultivation, certainly contributes to pollution, such contribution is exceeded by that deriving from industry and road traffic
Wet deposition at the base of Mt Everest: Seasonal evolution of the chemistry and isotopic composition
The chemistry of wet deposition was investigated during 2012–2014 at the Pyramid International Laboratory in the Upper Khumbu Valley, Nepal, at 5050 m a.s.l., within the Global Atmosphere Watch (GAW) programme. The main hydro-chemical species and stable isotopes of the water molecule were determined for monsoon rain (July–September) and snow samples (October–June). To evaluate the synoptic-scale variability of air masses reaching the measurement site, 5 day back-trajectories were computed for the sampling period. Ion concentrations in precipitation during the monsoon were low suggesting that they represent global regional background concentrations. The associations between ions suggested that the principal sources of chemical species were marine aerosols, rock and soil dust, and fossil fuel combustion. Most chemical species exhibited a pattern during the monsoon, with maxima at the beginning and at the end of the season, partially correlated with the precipitation amount. Snow samples exhibited significantly higher concentrations of chemical species, compared to the monsoon rainfall observations. Particularly during 2013, elevated concentrations of NO3−, SO42− and NH4+ were measured in the first winter snow event, and in May at the end of the pre-monsoon season. The analysis of large-scale circulation and wind regimes as well as atmospheric composition observations in the region indicates the transport of polluted air masses from the Himalayan foothills and Indian sub-continent up to the Himalaya region. During the summer monsoon onset period, the greater values of pollutants can be attributed to air-mass transport from the planetary boundary layer (PBL) of the Indo-Gangetic plains. Isotopic data confirm that during the monsoon period, precipitation occurred from water vapor that originated from the Indian Ocean and the Bay of Bengal; by contrast during the non-monsoon period, an isotopic signature of more continental origin appeared, indicating that the higher recorded NO3− and SO42− concentrations could be ascribed to a change in air circulation patterns. A comparison of recent monsoon deposition chemistry with data from the 1990's shows similar levels of contaminants in the rainfall. However, non-monsoon deposition can be significant, as it largely contributed to the ion wet deposition fluxes for all analyzed species in 2013
Valproic acid triggers erythro/megakaryocyte lineage decision through induction of GFI1B and MLLT3 expression
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Aplicación de la impregnación a vacÃo en la biopreservación de carne de pescado de rÃo
Entre RÃos presenta un destacado potencial para la piscicultura. Entre los peces que se desarrollan en la región, es posible destacar a la boga (Megaleporinus obtusidens), especie autóctona, migratoria, muy difundida y altamente demandada. En este contexto, los alimentos a base de pescado constituyen una buena alternativa debido a su mejor perfil lipÃdico. La carne de pescado es altamente perecedera; en este sentido, la incorporación de sobrenadantes libres de células de Lactiplantibacillus plantarum por impregnación a vacÃo representa una alternativa de conservación. Para establecer las condiciones de impregnación, se aislaron cepas de Pseudomonas de la boga entera y se realizaron pruebas de inhibición. La impregnación se estudió utilizando dos SLC que presentaron mayor capacidad de inhibición frente a las cepas aisladas: uno proveniente de cepas de aislado de maÃz (LpM2) y otro de sorgo (LpS10). A las muestras impregnadas se les determinó variación de peso, color, pH, nitrógeno básico volátil total (NBVT), bacterias psicrótrofas y bacterias proteolÃticas cada 3 dÃas durante un perÃodo de 15 dÃas de almacenamiento. La impregnación a vacÃo con el SLC de LpS10 resultó ser la mejor alternativa en términos del control del crecimiento microbiano y permitió disminuir los valores de pH y NBVT.
ARK/CAICYT: http://id.caicyt.gov.ar/ark:/s22504559/ru4xf6tn
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