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Abstract Agglutinated foraminifera from surface sediments of two sites (S1 and E1) in the North Adriatic Sea were investigated in order to detect their test composition and to explore possible links with the surrounding environment. Chemical-mineralogical analyses of the agglutinated tests by scanning Electron Microscopy and Energy Dispersive Spectroscopy, suggest that the chemical composition of the test surfaces generally mirrors the one of the sea-floor sediment. Only some species, as Reophax nana and Leptohalysis scottii exhibit a clear selectivity of the agglutinated grains. In detail, specimens of R. nana from site E1, which is mainly characterized by high hydrodynamic conditions at the sea-floor, show a preferential selection of mineral grains containing high concentrations of Zircon (Zr) and Titanium (Ti) even if these elements occur in very low concentrations in the surrounding sediment. L. scottii exclusively picks mica flakes to build the test. We suggest that the compositional differences recorded in the considered agglutinated foraminiferal tests represent distinctive life strategies in order to live successfully in different environments. Highlights • Agglutinated foraminifera were investigated in recent sediments from the Adriatic Sea. • Test surface mineralogical composition reflect the surrounding sediment. • Reophax nana select heavy minerals to survive in high energy environments. • Leptohalysis scottii use phillosilicates to build their test as adaptive strategy. [ABSTRACT FROM AUTHOR]

Time recurrences and slip rates of paleoearthquakes along offshore seismogenic faults represent one of the key challenges that the scientific community is facing off. Here we provide an integrated study combining geophysical, sedimentological and geochemical data in order to define slip rates and time recurrences of the Sant'Eufemia normal Fault (SE Tyrrhenian Sea). We have documented the paleo-events associated to this geological structure and reconstructed the paleoenvironmental history. From post-LGM (ca. 20,484 yr BP) to Present, four main events (EQ1, EQ2, EQ3, and EQ4) and the historical 1905 Calabria earthquake have been recognized. Time recurrence ranges from 4.68 ± 0.94 to 7.322 ± 1.84 ky (mean value of 5.4 ky), while the co-seismic vertical displacement ranges from 0.21 to 1.085 m (mean value of 0.68 m), indicating that slip rates change along the fault plane moving from the central part to the lateral edges. In this work we have defined a new class of active fault, here named "ultra-slow", that allowed to extend the range of time recurrences previously provided for the main earthquakes affecting the Southern Apennines. Phenomena that may be related with the oceanic slab sinking beneath the Calabrian arc. • Five paleoearthquakes have been identified on chirp profiles, sediment cores and geochemical data. • Slip rates and time recurrences of five events generated by a submarine seismogenic fault have been measured integrating dating from 14C AMS, Tephra, Pb-210 and biozones. • Catastrophic events identified at the hanging wall and footwall of an active fault have been correlated using the bio-stratigraphic analysis. • An ultra-slow earthquake category has been introduced in the active fault systems of the Apennines. • Since LGM, the paleoenvironmental analysis highlighted that the gulf has mainly suffered erosion due to water currents coming from emerged areas. [ABSTRACT FROM AUTHOR]

• he advent of EUV/X-ray FEL sources combined with instrumental advances have permitted to develop the nanoscale transient grating approach. - The performance of the two set-ups, designed and operated at FERMI, demonstrates significant research advances in condensed matter dynamics. • The EUV/soft x-ray transient grating method can be further exploited for addressing more exotic and unexplored matter properties. The development of ultra-bright extreme ultraviolet (EUV) and X-ray free electron laser (FEL) sources has enabled the extension of wave-mixing approaches into the short wavelength regime. Such a class of experiments relies upon nonlinear interactions among multiple light pulses offering a unique tool for exploring the dynamics of ultrafast processes and correlations between selected excitations at relevant length and time scales adding elemental and site selectivity as well. Besides the availability of a suitable photon source, the implementation of wave mixing methodology requires efforts in developing the instrumental set-up. We have realized at the FERMI FEL two dedicated set-ups to handle multiple FEL beams with preselected parameters in a non-collinear fashion and control their interaction sequence at the target. These unique apparatuses, combined with the exceptional characteristics of the seeded FERMI FEL, have allowed us to make the first steps into this field and further advances are foreseen in the near future. [ABSTRACT FROM AUTHOR]

Abstract: In order to determine the factors controlling the distribution of planktonic foraminifera as a proxy for reconstruction of paleoenvironments, we present data on live assemblages collected in the Southern Ocean. Plankton tows and hydrographic measurements were taken in the upper 400 m of the water column at different sites in the Ross Sea (site B) and at the Polar Front of the Pacific Ocean (site O) during austral summers from 1998 to 2003. Based on qualitative micropaleontological observations we discriminated between Neogloboquadrina pachyderma dextral (dex) and N. pachyderma sinistral (sin). In addition for N. pachyderma (sin) we distinguished four morphs: the first one (1) has a thickened test and depressed sutures; the second morph (2) is represented by specimens characterized by a subspheric and heavily encrusted test; the third morph (3) has a thin and lobate walled test; the fourth one (4) represent the juvenile stage of N. pachyderma (sin) and is characterized by a smaller average size. The microfauna collected in the Ross Sea (site B) is characterized by the dominance of N. pachyderma (sin) (morphs 1 and 2), whereas low occurrences of Turborotalia quinqueloba, N. pachyderma (dex) and Neogloboquadrina dutertrei were noted in the first 50 m of the water column. The water column at this station is characterized by a marked and shallow stratification and a marked thermocline during the sampling season. At the ocean station (site O), the assemblage shows increasing diversification: T. quinqueloba, G. bulloides, N. pachyderma (dex) and few specimens of Globigerinita uvula characterize the planktonic microfauna. There is a predominance of non-encrusted morphs and juvenile specimens (3 and 4). At this station the mixed surface layer is deeper than in the Ross Sea (60–70 m), the pycnocline and the thermocline less marked. The depth and the intensity of the Deep Chlorophyll Maximum (DCM) influence foraminiferal distribution: N. pachyderma (sin) shows abundance peaks at or just below the DCM while G. bulloides peaks above the DCM. Coiling direction of N. pachyderma seems to be not controlled exclusively by Sea Surface Temperature (SST): probably the two coiling types are genetically different. Results document that diversity of planktonic foraminifera, number of specimens and variations in test morphology are related to regional differences in water properties (temperature, salinity, and DCM depth). [Copyright &y& Elsevier]

Trace Metals (TMs: Pb, Zn, Cu, Cr, Cd, and Ni), major elements (Al and Fe) and radionuclides (210Pb/137Cs) investigations on EL-C01 sediment core provides new information on sedimentary regime and anthropogenic impacts during the last 175 years in the Po river prodelta area. The results allow to identify some TMs/Al peak in the upper part of the core, likely related to the major flood events of the Po river during the XXth century. Sediments deposited after the year 1900 exhibit a gradual increase of some TMs concentrations compared to pre-industrial era values. In particular, Pb, Zn, and Cu high contents are detected after the World War II and during the "Italian Economic Miracle" period. The decrease of heavy metal (Zn and Pb) contents from the second half of the 1980s is probably the effect of the Italian Law 319/76 and anti-pollution environmental policies concerning industrial and urban emitters. • Po river prodelta 175 yr environmental history reconstructed from a sediment core • Trace metal peaks identify Po river major flood events during the XXth century • Cu, Pb, and Zn trends relate to the economic/industrial Italian history • Pre-industrial Pb and Zn concentrations of 31 and 91 mg kg−1 respectively [ABSTRACT FROM AUTHOR]

Abstract: The dynamical link between mean state biases and dominant timescales of interannual variability is examined using the output from two state-of-the-art coupled model simulations, results from an ocean-only simulation forced with observed surface fields, and various observational data sets. The focus of this study is the relative role of the mean upper ocean density structure vs. anomalous wind forcing in controlling the spectral characteristics of tropical Pacific interannual variability. It is shown that an extensive South Pacific Convergence Zone (SPCZ) creates a potential vorticity (PV) barrier in the Southern Hemisphere similar to the one associated with the Intertropical Convergence Zone (ITCZ) in the Northern Hemisphere in both climate models. The PV barrier in the Southern Hemisphere strongly constrains the mean equatorward flow in the ocean model pycnocline, creating a “choke point” for the mean flow around 10°S. It is then examined whether the PV barrier can also limit the anomalous flow associated with mass recharge/discharge to/from the equatorial thermocline at interannual timescales. If the anomalous flow were impeded by the mean PV structure the meridional extent of the area involved in the mass recharge/discharge process would be narrower, leading to a shorter adjustment (and ENSO) timescale. Comparison of the two climate models, both of which have similarly erroneous PV structures in the southern tropical Pacific, but different interannual timescales, shows that the meridional extent of the anomalous meridional transport is primarily controlled by the latitudinal location of the wind stress curl anomalies, while the mean state bias in the Southern Hemisphere does not seem to have any significant influence. [Copyright &y& Elsevier]

Abstract: Tropical Pacific interannual variability is examined in nine state-of-the-art coupled climate models, and compared with observations and ocean analyses data sets, the primary focus being on the spatial structure and spectral characteristics of El Niño-Southern Oscillation (ENSO). The spatial patterns of interannual sea surface temperature (SST) anomalies from the coupled models are characterized by maximum variations displaced from the coast of South America, and generally extending too far west with respect to observations. Thermocline variability is characterized by dominant modes that are qualitatively similar in all the models, and consistent with the “recharge oscillator” paradigm for ENSO. The meridional scale of the thermocline depth anomalies is generally narrower than observed, a result that can be related to the pattern of zonal wind stress perturbations in the central-western equatorial Pacific. The wind stress response to eastern equatorial Pacific SST anomalies in the models is narrower and displaced further west than observed. The meridional scale of the wind stress can affect the amount of warm water involved in the recharge/discharge of the equatorial thermocline, while the longitudinal location of the wind stress anomalies can influence the advection of the mean zonal temperature gradient by the anomalous zonal currents, a process that may favor the growth and longer duration of ENSO events when the wind stress perturbations are displaced eastwards. Thus, both discrepancies of the wind stress anomaly patterns in the coupled models with respect to observations (narrow meridional extent, and westward displacement along the equator) may be responsible for the ENSO timescale being shorter in the models than in observations. The examination of the leading advective processes in the SST tendency equation indicates that vertical advection of temperature anomalies tends to favor ENSO growth in all the CGCMs, but at a smaller rate than in observations. In some models it can also promote a phase transition. Longer periods tend to be associated with thermocline and advective feedbacks that are in phase with the SST anomalies, while advective tendencies that lead the SST anomalies by a quarter cycle favor ENSO transitions, thus leading to a shorter period. [Copyright &y& Elsevier]

Abstract: We have investigated the scattering mechanisms limiting the low-temperature electron mobility in unintentionally doped In0.75Al0.25As/In0.75Ga0.25As metamorphic quantum wells grown on GaAs (001) substrates. We found that the mobility is limited by background impurity scattering for densities lower than 2.0×1011 cm−2, and by the combination of this mechanism and alloy disorder scattering for higher densities. From such analysis we estimate an alloy disorder scattering potential of about 0.5±0.1eV. Moreover we show that when a strained InAs layer is located in the centre of the In0.75Ga0.25As well, the alloy disorder scattering can be reduced, yielding mobilities up to 320000cm2/Vs at a carrier concentration of 3.1×1011 cm−2. [Copyright &y& Elsevier]