4,894 research outputs found

    Quality of soil and water in deltaic deposits of Louros and Arachthos rivers related to karstic rocks of the wider area

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    Οι υδρογραφικές λεκάνες των ποταμών Λούρου και Αράχθου αναπτύσσονται κυρίως σε καρστικά πετρώματα από ασβεστόλιθους, δολομίτες και δευτερευόντως γύψων. Τα εδάφη στο δελταϊκό πεδίο των δύο ποταμών, όπως αναμενόταν, είναι επαρκώς εφοδιασμένα με CaCOi και υπάρχει φυσική τροφοδοσία σε Ca++. Οι τιμές της Ικανότητας Ανταλλαγής Κατιόντων (ΙΑΚ) στα εδάφη είναι υψηλές με κυριαρχία των εναλλακτικών ιόντων Ca++ και δευτερευόντως Mg++ . Στα νερά του Δέλτα τόσο του φρεατίου όσο και του υπόγειου υδροφόρου ορίζοντα η περιεκτικότητα σε ιόντα Ca++ είναι υψηλή. Η διακύμανση των τιμών των ιόντων HCOî στο νερό του υπόγειου υδροφόρου είναι σε φυσιολογικά επίπεδα. Τα υπάρχοντα SO/ στα νερά προέρχονται από την καρστικοποίηση της γύψου και του ανυδρίτη. Οι τιμές των ιόντων Να+ και CT είναι υψηλότερες στα νερά του φρεατίου υδροφόρου από αυτά του υπόγειου υδροφόρου ορίζοντα. Τα νερά του Δέλτα κατατάσσονται στα ανθρακικά, χωρίς ιδιαίτερη επίδραση από τη θάλασσα. Υπάρχει συνεπώς άμεση εξάρτηση της ποιότητας των εδαφών και των νερών του Δέλτα με την ύπαρξη των καρστικών σχηματισμών κυρίως των ανθρακικών και σε μικρό βαθμό των εβαποριτώνThe present study focuses on the connection between the existing karstic formations and the quality of soil and water in the River Delta area. The hydrological basins of Louros and Arachthos Rivers (NW Greece) are partially developed on karstic rocks. So the soil is enriched with CaC03 and there is a natural supply of Ca++, which originates mainly from the limestone and secondarily from gypsum formations. The value of the Cation Exchange Capacity (CEC) of soil is high and in the exchange sites Ca++ ions dominate and Mg++ secondarily. Delta water ofphreatic and confined aquifer contain high Ca++ ion concentrations. The fluctuation of HCO3 values in confined aquifer water is within normal levels. Ions of SO 4 ' that occur in water are derived from the karstic process of gypsum and anhydrite formations. The values ofNa+ and CT content in water are higher in the phreatic aquifer than in ground water. The water in the area of the River Delta is classified as Carbonic water, despite its proximity to the sea. Therefore, the quality of soil and water of the River Delta area is highly related to the karstic process of carbonate formations, mainly of calcareous and secondarily evaporate sediment

    Copper removal from industrial wastewaters by means of electrostatic shielding

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    Electrostatic shielding zones made of electrode graphite powder were used as a new type of ionic and electronic currentsinks. Because of the local elimination of the applied electric field, voltage and current within the zones, ions are led insidethem and accumulate there. We implemented the current sinks in electrodialysis of a simulated copper plating rinse watercontaining 100 mg L-1 Cu2+ ions and electrodeionization of a 0.001 M CuSO4 solution with simultaneous electrochemicalregeneration of the used ion exchange resin beds and obtained pure water with a Cu2+ ion concentration of less than 0.12 mgL-1 at a flow rate of 1.29x10-4 L s-1 diluate stream and a current density of 2 mA cm-2

    Differences in the Prevalence of Sarcopenia in Community-Dwelling, Nursing Home and Hospitalized Individuals. A Systematic Review and Meta-Analysis

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    © 2019, Serdi and Springer-Verlag International SAS, part of Springer Nature. Background: Sarcopenia is an age-related disease which leads to a decline in muscle mass and function and is one of the most important health issues in elderly people with a high rate and variety of adverse outcomes. Objective: The current systematic review and meta-analysis study was carried out to estimate the overall prevalence of sarcopenia in both males and females in different regions around the world and to show the major differences in its occurrence among different populations. Design: A systematic review and metaanalysis of studies published in PubMed (Medline) and Scopus. Participants: Community dwelling, nursing home and hospitalized older adults aged over 60 years. Measurements: Sarcopenia was defined by the major validated diagnostic criteria, such as the European Working Group on Sarcopenia in Older People (EWGSOP), the Asian Working Group for Sarcopenia (AWGS) and the International Working Group on Sarcopenia (IWGS). The model used was the random effect model for estimating the prevalence of sarcopenia. The sex-specific prevalence of sarcopenia as well as 95% CI (Confidence interval) were calculated using MetaXL (version 5.3). Heterogeneity assessment was carried out by subgroup analysis. Results: We included 41 studies with a total of 34955 participants. The prevalence of sarcopenia in community-dwelling individuals in the included studies were 11% (95% CI: 8–13%) in men and 9% (95% CI: 7–11%) in women. The prevalence of sarcopenia in nursing-home individuals in the included studies were 51% (95% CI: 37–66%) in men and 31% (95% CI: 22–42%) in women and in hospitalized individuals were 23% (95%, CI: 15–30%) in men and 24% (95% CI: 14–35%) in women. Conclusions: Despite the differences encountered between the studies, regarding diagnostic tools used to measure of muscle mass, different regions around the world and different populations and clinical settings, this systematic review revealed that a significant proportion of old people has sarcopenia (major in nursing homes), even in populations healthy in general. However, sarcopenia is caused by the aging progress, early diagnosis and individualized care, including physical activity and nutrition, can prevent some adverse outcomes in all populations

    Superconductivity and spin-glass like behavior in system with Pd sheet sandwiched between graphene sheets

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    Pd-metal graphite (Pd-MG) has a layered structure, where each Pd sheet is sandwiched between adjacent graphene sheets. DC magnetization and AC magnetic susceptibility of Pd-MG have been measured using a SQUID magnetometer. Pd-MG undergoes a superconducting transition at TcT_{c} (=3.63±0.04= 3.63 \pm 0.04 K). The superconductivity occurs in Pd sheets. The relaxation of MZFCM_{ZFC} (aging), which is common to spin glass systems, is also observed below TcT_{c}. The relaxation rate S(t)S(t) shows a peak at a characteristic time tcrt_{cr}, which is longer than a wait time twt_{w}. The irreversibility between χZFC\chi_{ZFC} and χFC\chi_{FC} occurs well above TcT_{c}. The susceptibility χFC\chi_{FC} obeys a Curie-Weiss behavior with a negative Curie-Weiss temperature (13.1Θ5.4-13.1 \leq \Theta \leq -5.4 K). The growth of antiferromagnetic order is limited by the disordered nature of nanographites, forming spin glass-like behavior at low temperatures in graphene sheets.Comment: 21 pages, 15 figures; submitted to J. Phys.: Condensed Matte
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