36 research outputs found

    Geochemical Characterization of Groundwater in a Volcanic System

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    A geochemical investigation was undertaken at Mt. Etna Volcano to better define groundwater characteristics of its aquifers. Results indicate that the Na?Mg ± Ca-HCO3− ± (SO42− or Cl−) type accounts for more than 80% of the groundwater composition in the volcano. The remaining 20% is characterized by elevated Ca2+. Waters along coastal areas are enriched in SO42− or Cl−, mainly due to mixing with seawater and anthropogenic effects. The majority of the samples showed values between −4% to −9% for δ18O and −19? to −53% for δ2H, suggesting that precipitation is the predominant source of recharge to the aquifers, especially in the west of the study area. The analysis of δ13C and pCO2 shows values 1 to 3 times higher than those expected for waters in equilibrium with the atmosphere, suggesting a partial gas contribution from deep sources. The diffusion of gasses is likely to be controlled by tectonic structures in the volcano. The ascent of deep brines is also reflected in the CO2 enrichment (up to 2.2 bars) and enriched δ2H/δ18O compositions observed in the salt mounts of Paternò.Fil: Bellia, Carmelo . National Institute of Advanced Industrial Science and Technology. Geological Survey of Japan; JapónFil: Gallardo, Adrian Hugo. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Geologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Yasuhara, Masaya . National Institute of Advanced Industrial Science and Technology. Geological Survey of Japan; JapónFil: Kazahaya, Kohei . National Institute of Advanced Industrial Science and Technology. Geological Survey of Japan; Japó

    Factors Affecting Energy Metabolism and Prognosis in Patients with Amyotrophic Lateral Sclerosis.

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    Background/aims:Nutritional status is a factor affecting prognosis in patients with amyotrophic lateral sclerosis (ALS). Here, we aimed to clarify the factors associated with hypermetabolism and the prognosticators of ALS.Methods:Forty-two inpatients (22 men, 20 women) diagnosed with ALS according to the revised El-Escorial criteria were investigated. The following data were retrospectively analyzed: anthropometric measurements, blood biochemistry, disease severity, basal energy expenditure (BEE), resting energy expenditure (REE) measured by indirect calorimetry, spirometry, and bioelectrical impedance analysis. Single and multiple regression analysis was performed to examine factors affecting REE and metabolic changes (defined as the ratio of REE to fat-free mass [FFM]). The Kaplan-Meier method was used to examine factors associated with the occurrence of cumulative events (death or tracheostomy).Results:Among the 42 inpatients, REE was significantly higher than BEE, indicating hypermetabolism in ALS. Multiple regression analysis revealed that REE/FFM is strongly associated with the skeletal muscle index (-3.746 to -1.532, p < 0.0001) and percent forced vital capacity (%FVC) (-0.172 to -0.021, p = 0.013). Moreover, both the skeletal muscle index and %FVC were significant prognosticators associated with the occurrence of cumulative events.Conclusions:Energy metabolism was elevated in ALS, and respiratory status and muscle mass were associated with the hypermetabolism and poor prognosis. Adequate nutritional support may improve outcomes in ALS by preventing deterioration of respiratory status and reduction in muscle mass

    Mixing of magmatic CO2 into volcano groundwater flow at Aso volcano assessed combining carbon and water stable isotopes

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    To understand deep groundwater flow systems and their interaction with CO2 emanated from magma at depth in a volcanic edifice, deep groundwater samples were collected from hot spring wells in the Aso volcanic area for hydrogen, oxygen and carbon isotope analyses and measurements of the stable carbon isotope ratios and concentrations of dissolved inorganic carbon (DIC). Relations between the stable carbon isotope ratio (δ13CDIC) and DIC concentrations of the sampled waters show that magma-derived CO2 mixed into the deep groundwater. Furthermore, groundwaters of deeper areas, except samples from fumarolic areas, show higher δ13CDIC values. The waters' stable hydrogen and oxygen isotope ratios (δD and δ18O) reflect the meteoric-water origin of that region's deep groundwater. A negative correlation was found between the altitude of the well bottom and the altitude of groundwater recharge as calculated using the equation of the recharge-water line and δD value. This applies especially in the Aso-dani area, where deeper groundwater correlates with higher recharge. Groundwater recharged at high altitude has higher δ13CDIC of than groundwater recharged at low altitude, strongly suggesting that magmatic CO2 is present to a much greater degree in deeper groundwater. These results indicate that magmatic CO2 mixes into deeper groundwater flowing nearer the magma conduit or chamber
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