A novel hydrogeochemical approach to delineate the origin of potentially toxic elements in groundwater: Sophisticated molar ratios as environmental tracers.

The occurrence, mobilization, and origin of Potentially Toxic Eelements (PTEs) in the environment is always a difficult research question that has not been fully addressed to date; solving this problem would be a major achievement for environmental science and pollution research, a significant scientific breakthrough, and an important contribution to environmental analysis and monitoring. The lack of a holistic methodology that uses chemical analysis to determine the origin of each PTE in the environment is the main motivation for this project. Therefore, the hypothesis tested here is to develop a scientific approach applied to each PTE to determine whether its origin is geogenic (i.

Objective Response to First-Line Treatment as a Predictor of Overall Survival in Metastatic Breast Cancer: A Retrospective Analysis from Two Centers over a 25-Year Period.

Introduction: The purpose of this study was to study the efficacy of subsequent treatment lines for metastatic breast cancer (MBC), as well as the association between radiologic objective response rate (ORR) and overall survival (OS).

Methods: In this retrospective study, consecutive patients treated for MBC in two centers in Greece from January 1, 1992, to December 31, 2016, were identified and clinicopathologic data regarding tumor characteristics and administered treatments were collected. The efficacy per treatment line in terms of ORR, progression-free survival (PFS) and OS, as well as the prognostic value of ORR at first line were investigated.

Expounding the origin of chromium in groundwater of the Sarigkiol basin, Western Macedonia, Greece: a cohesive statistical approach and hydrochemical study.

The aim of this paper is to provide a methodology including statistical tools and spatial techniques, in order to identify the various potential sources of chromium (Cr) in the Sarigkiol basin, Western Macedonia, Greece, where elevated concentrations of Cr in groundwater have been recorded since 1996. Integrated hydrochemical approach and statistical analyses including Pearson's correlation coefficient, multivariate statistical analyses (factor analysis and hierarchical cluster analysis), and spatial techniques (Moran's I spatial autocorrelation index and bivariate local indicator spatial association cluster map) were applied to evaluate the chemical analyses of 73 water samples, from irrigation wells, natural springs, and surface water. Both natural and anthropogenic sources of Cr were recorded; the first (ultramafic-dominated environment) is strongly depicted on the natural spring water, in which Cr concentrations as high as ~ 130 μg/L were recorded, whereas the second (agricultural activities) acts synergistically in the irrigation wells of the Sarigkiol basin, in which strong correlations of Cr, P, and NO were defined.

The synergistic role of agricultural activities in groundwater quality in ultramafic environments: the case of the Psachna basin, central Euboea, Greece.

In the present study, we approach the geochemical processes affecting the hydrochemistry and resulting in elevated concentrations of hexavalent chromium (Cr) in groundwater of the Psachna basin, central Euboea, Greece. Sixty-five groundwater samples and 16 topsoil (5-20 cm) samples were studied in order to examine groundwater and soil quality in relation to geogenic processes and anthropogenic activities. Specifically, the origin of Cr and Cr in groundwater was investigated by co-evaluating (a) hydrochemical cross plots of major ions; (b) spatial distribution maps of Cl, Mg, NO, and Cr; (c) multivariate statistical analyses such as factor analysis (FA) and hierarchical cluster analysis (HCA) of groundwater geochemistry; (d) chemical analyses of soil samples; and (e) chemical analyses of fertilizers.