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At the end of the Messinian salinity crisis, changes in the\ud palaeoceanography and palaeoclimate induced a transition\ud from hypersaline to hyposaline conditions in the Mediterranean\ud water body. Detailed investigation of natural radioactivity and\ud microfacies analyses of two early post-evaporitic Messinian\ud sections show that the transition occurred in poorly oxygenated\ud and well-stratified water masses. These transitional\ud deposits, which mainly consist of marls and CaCO3-rich\ud horizons, are generally well laminated and totally barren\ud in benthic and planktonic fauna. The presence of barite, small\ud (5–8 lm) authigenic framboidal pyrite, and high values of U\ud indicate persistent anoxic conditions during the early postevaporitic\ud Messinian stage in the Adriatic sub-basin of the\ud Mediterranean Sea. The presence of post-evaporitic welllaminated\ud barren deposits from both Mediterranean borderland\ud sections and ODP sites suggests that these anoxic\ud conditions extended to other sub-basins of the Mediterranean\ud region

Paleoenvironmental and paleoclimate changes that occurred during the late postevapo ritic stage of the Mediterranean Basin in the Messinian foreland domain of the Adriatic region offer a new perspective on the relationship between orbital forcing and climate response. The magnetic susceptibility record of the Fonte dei Pulcini A section (Maiella Mountains, Italy) allows us to orbitally tune the record between 5.394 and 5.336 Ma and to temporally constrain the paleoenvi ronmental and paleoclimate changes evidenced by quantitative paleontological (palynomorphs, ostracods, and calcareous nannofossils), stable isotope (δ 18 O and δ 13 C), and X-ray diffraction (XRD) analyses. The base of the Fonte dei Pulcini A section is characterized by Paratethyan ostracods and dinocysts, which point to the late Messinian Lago-Mare biofacies (Loxocorniculina djafarovi zone) of the Mediterranean Messinian stratigraphy. From paleontological and geochemical (δ 18 O) analyses, there is no evidence of a marine incursion in the Fontedei Pulcini A section. The major changes in terms of paleodepth, paleosalinity, evaporation versus precipitation, aridity versus humidity, and reworking processes occurred in the upper part of the Fonte dei Pulcini A section, during the last Messinian insolation cycle (i-cycle 511/512), which is characterized by high-amplitude oscillations. In contrast, the lower part of the Fonte dei Pulcini A section, which was deposited during relatively low-amplitude insolation cycles, is characterized by more stable environmental conditions. Comparing summer insolation with the paleoenvironmental changes at the Fonte dei Pulcini A section, we identify delays of several thousands of years between orbital forcing and climate response.

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We investigated second order optical nonlinearity of zinc oxide thin films, grown on glass substrates by the dual ion beam sputtering technique under different deposition conditions. Linear optical characterization of the films was carried out by spectrophotometric optical transmittance and reflectance measurements, giving the complex refractive index dispersion. Resistivity of the films was determined using the four-point probe sheet resistance method. Second harmonic generation measurements were performed by means of the Maker fringes technique where the fundamental beam was originated by nanosecond laser at λ=1064nm. We found a relatively high nonlinear optical response, and evidence of a dependence of the nonlinear coefficient on the deposition parameters for each sample. Moreover, the crystalline properties of the films were investigated by x-ray diffraction measurements and correlation with second order nonlinearity were analyzed. Finally, we investigated the influence of the oxygen flow rate during the deposition process on both the second order nonlinearity and the structural properties of the samples.

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