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This study deals with the evolution of strength and microstructure in pure nickel during wire drawing from an initial diameter of 1.74 mm to 30 μm, corresponding to a total true strain of 8.1. Electron backscattering diffraction (EBSD) and X-ray diffraction (XRD) have been used for microstructural characterization. In the later stages of deformation, the fraction of low angle boundaries decreased as did the misorientations within a grain or cell. The dislocation density stabilized at ∼2 × 1015 m−2, and the activation volume decreased from ∼100 b3 at a strain of 1 to ∼ 15 b3 at strains ≳4, where b is the magnitude of the Burgers vector. Cross-sectional EBSD of the wires revealed that a core region had <111> fiber texture, whereas a peripheral shell region had a complex fiber texture due to redundant shear strain. Viscoplastic self-consistent (VPSC) simulations were in good agreement with the crystallographic texture evolution in the wires during drawing. The wire drawing data is compared with other deformation techniques, to provide a broad framework for analyzing microstructure-strength-ductility relationships. At large strains of >2, with an essentially constant dislocation density, the strength can be related solely to Hall-Petch strengthening by a refinement of the transverse grain size. [Display omitted] [ABSTRACT FROM AUTHOR]

Combined oral contraceptives, comprising of both an oestrogen and a progestin component, are released in aquatic environments and potentially pose a risk to aquatic wildlife by their capacity to disrupt physiological mechanisms. In this study, the endocrine disruptive potential of two mixtures, 17α-ethinylestradiol (EE2), a synthetic oestrogen, or estetrol (E4), a natural oestrogen, with the progestin drospirenone (DRSP) have been characterised in three generations of zebrafish, according to an adapted Medaka Extended One Generation Reproduction Test. Zebrafish (Danio rerio) were exposed to a range of concentrations of EE2/DRSP and E4/DRSP (∼1×, ∼3×, ∼10× and ∼30× predicted environmental concentration, PEC). Survival, growth, hatching success, fecundity, fertilisation success, vitellogenin (VTG), gonad histopathology, sex differentiation, and transcriptional analysis of genes related to gonadal sex steroid hormones synthesis were assessed. In the F0 generation, exposure to EE2/DRSP at ∼10 and ∼30× PEC decreased fecundity and increased male VTG concentrations. The highest concentration of EE2/DRSP also affected VTG concentrations in female zebrafish and the expression of genes implicated in steroid hormones synthesis. In the F1 generation, sex determination was impaired in fish exposed to EE2/DRSP at concentrations as low as ∼3× PEC. Decreased fecundity and fertility, and abnormal gonadal histopathology were also observed. No effects were observed in the F2 generation. In contrast, E4/DRSP induced only minor histopathological changes and an increase in the proportion of males, at the highest concentration tested (∼30× PEC) in the F1 generation and had no effect on hatching success of F2 generation. Overall, this study suggests that the combination E4/DRSP has a more favourable environmental profile than EE2/DRSP. [ABSTRACT FROM AUTHOR]