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Biomphalaria glabrata snails were infected with Schistosoma mansoni and maintained at different dilutions of artificial ocean water for up to 4 weeks. Glucose and maltose concentration of the digestive gland-gonad complex were analyzed by high-performance thin-layer chromatography at different stages of the infection. B. glabrata snails were divided into three experimental groups: Group A, snails with early prepatent infection (10 days post-infection); Group B, snails with late prepatent infection (22 days post-infection); and Group C, snails with patent infection (45 days post-infection). Infected snails in A were maintained at different salinities for 2 weeks and then necropsied, and their two main simple sugars, i.e., glucose and maltose, were analyzed. Groups B and C contained two subgroups: the first subgoups were analyzed after 2 weeks, and the second after 4 weeks. Controls for these experiments were maintained identically in either deionized water or artificial spring water. Maltose and glucose were extracted from the digestive gland-gonad complex in ethanol-water (70:30). 1-Butanol-glacial acetic acid-diethyl ether-deionized water (27:18:5:3) mobile phase was used to separate sugars on EMD Millipore silica gel preadsorbent plates. Sugars were detected using α-naphthol-sulfuric acid reagent and quantified with a CAMAG TLC Scanner 3 at 515 nm. The obtained data were compared using analysis of variance (ANOVA) single factor statistical analysis. Statistical differences were not found in any sugars in Group A snails. For glucose, a significant difference was found after 4 weeks in both B and C snails. For maltose, a significant difference was found after 4 weeks in B snails and after 2 weeks in C snails. Different salinity levels affect the maltose and glucose concentrations of adult B. glabrata snails infected with S. mansoni.

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Journal of Thermal Analysis and Calorimetry
Authors: Lidiane Pinto Correia, Elisana Afonso de Moura, Hallisson Meneses Pires, and Rui Oliveira Macêdo

, with different purposes [ 3 – 6 ]. This study aimed to evaluate the thermal characterization of different salinities water by DSC-cooling. Experimental Samples The samples were collected in Serra

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Biological Development Co., Ltd. (purity: ∼99%). Saline (medical), Glucose (medical). Equipment and conditions Thermoanalyzer Systems (American Thermoanalyzer Companies Inc.) were used for determining the DSC–TG curves of

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Abstract  

An establishéd electrodeposition method for separating americium and plutonium from highly saline used-fuel-leaching solutions has been extended to the determination of Np and U in saline groundwaters. The interference of major ionic species in groundwater on the yield was investigated using three groundwaters of varying salinity (ionic strength I=1.37, 0.0748 and 0.0253 mol/l). High average yields (>92%), and good reproducibility were obtained for Np and U electroplated from solutions with ionic strength less than 0.1. The greatest interferences from individual ions were caused by Mg2+ and HCO 3 .

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The statistical analysis of salinity data from samples collected yearly from genetic soil horizons of 69 points of the Hungarian Soil Information and Monitoring System between 1992 and 2000 showed changes in time. There is a strong atmospheric control over the groundwater level and the resulting soil salinity. Weak statistical association was established between either the pattern of yearly soil salinity changes in the second (10-20 cm) and third (30-40 cm) genetic horizon and the groundwater observation stations or the soil types. In the area of Kecskemét there was a tendency of decreasing soil salinity patterns, while around Békéscsaba a tendency of increasing soil salinity patterns, as illustrated by the correspondence biplot. Regarding soil types, the solonetzic meadow soil showed a tendency of increasing salinity. It was concluded that the statistical analyses of the monitored data must be carefully planned in order to provide the optimal background data as independent data from all those available to accompany the monitored soil data as dependent variable.

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Abstract  

Viscoelastic properties of κ-carrageenan in saline solution at various concentrations and pH were investigated by dynamic rheological techniques, viscosity, elasticity measurements, and IR spectrometry. The viscosity and elasticity at low concentrations of κ-carrageenan do not depend on pH, confirming that κ-carrageenan is in a disordered conformation. At 0.7% κ-carrageenan, the disordered confirmation transforms into an ordered helical confirmation with the possibility of weak-type gel formation. The transformation is also confirmed by dynamic measurements of loss and storage moduli. Furthermore, at this concentration, the viscosity and elasticity are highly dependent on pH. At higher concentrations of NaCl (0.5 M) at some pHs, we observed that storage moduli is greater than loss moduli for the entire frequency region. Hence, there is a possibility of structure transformation from weak-type gel to a somewhat intermediate gel. The lowest viscosity and elasticity were obtained at extreme pH, confirming that there are structural changes occurring at these pHs due to hydrolysis. This is confirmed by IR data.

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Abstract  

A method for the determination of uranium and 210Po in high salinity water samples has been elaborated. Both radionuclides are preconcentrated from 0.5 dm3 saline media by co-precipitation with hydrated manganese dioxide, followed by dissolution of the precipitate in 200 mL of 1 M HCl. Uranium isotopes 235U and 238U can be directly determined by ICP MS method with a detection limit of 0.01 ppb for 238U. Prior to a selective determination of 210Po, the majority of other naturally occurring α-emitting radionuclides (uranium, thorium and protactinium) can be stripped from this solution by their extraction with a 50% solution of HDEHP in toluene. Finally, 210Po is simply separated by direct transfer to an extractive scintillator containing 5% of trioctylphosphine oxide in Ultima Gold F cocktail and determined by an α/β separation liquid scintillation technique with detection limit below 0.1 mBq/dm3.

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Abstract  

Clays high in Mg content occur frequently in the high saline environment of salt lakes in southern Tunisia. The DTA curves of these clays show a striking endothermic-exothermic reaction in the temperature range of 800–820�C. A strong correlation is observed between the intensity of these coupled reactions and the Mg content of the initial clay sample. The initial endothermic reaction is interpreted as the melting/dehydroxylation of the Mg-bearing smectites. The subsequent exothermic peak is interpreted as caused by the crystallisation of the new Mg-silicate phase enstatite. Therefore, the DTA is considered as a suitable method for the identification and relative quantification of high Mg clay minerals (e.g. trioctahedral smectites). Variations of the Mg content of the studied samples were well detectable by means of DTA, disclosing a distinct distribution pattern of the salt lake clays. Clues to bulk chemical composition of the initial clay assemblage can also be found in the results of the X-ray analysis of the firing products.

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Abstract  

A simple method for the determination of trace concentrations of metals in saline water is described. The analytical procedure involves the separation of metal ions of Cu, Zn, Hg and Fe by precipitation with diethyldithiocarbamate (DDTC). The radioisotope X-ray fluorescence method using Si(Li) detector has been applied for the determination of metal ions closed in the DDTC deposition.

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In the hydrogeologically closed Carpathian Basin subsurface waters have particular importance in the salinization/alkalization processes. In the poorly-drained low-lying areas the capillary flow transports high amounts of water soluble salts from the shallow, „stagnant” groundwater with high salt concentration and unfavourable sodium-carbonate(bicarbonate) type ion composition to the overlying soil horizons. Due to the strongly alkaline soil solution, the Ca and Mg salts (mostly carbonates and bicarbonates) are not soluble and Na + became absolutely predominant in the migrating soil solution which leads to high ESP even at relatively low salt concentration. High Na + saturation of heavy-textured soils with high amount of expanding clay minerals results in unfavourable physical-hydrophysical properties and extreme moisture regime of these soils, which are their main ecological constrains and the limiting factors of their fertility, productivity and agricultural utility. The simultaneous hazard of waterlogging or overmoistening, and drought sensitivity in extensive lowland areas, sometimes in the same places within a short period, necessitates a precise, “double function” soil moisture control against their harmful ecological/economical/social consequences. Most of the environmental constrains (including salinity/alkalinity/sodicity) can be efficiently controlled: prevented, eliminated, or - at least - moderated. But this needs permanent care and proper actions: adequate soil and water conservation practices based on a comprehensive soil/land degradation assessment. It includes continuous registration of facts and changes (monitoring); exact and quantitative knowledge on the existing soil processes, their influencing factors and mechanisms.

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