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The integrated chemo-, bio- and sequence stratigraphy from the Cenomanian-Coniacian base-of-slope succession of Monte Turno (Abruzzo, central Italy) provides a fine scale calibration of the local sea-level curve inferred from the adjacent platform to records of global sea-level change. Our results indicate that regional marine regressions were coincident with episodes of global cooling and sea-level fall, providing evidences for a causal link between climate changes and sea-level changes. The presence of small polar icecaps during the assumed ice-free Cretaceous is a likely explanation for the observed pattern.

A systematic investigation evaluated the concentrations of a selected number of trace elements (Cd, Co, Cu, Li, Ni, Pb, V and Zn) in carbonates of the benthic foraminifera Ammonia tepida collected from surface sediments of the highly polluted harbour of Naples. Application of cleaning procedures, combined with Scanning Electron Microscopy investigation (SEM) of the analysed shells allowed reliable quantification of the elements in the carbonate lattice. Adoption of biogenic carbonate/seawater distribution coefficients reported in the literature provided the ranges of variability of total dissolved trace elements in the studied marine environment. Very high concentrations of Zn, Cd, and Cu calculated in seawater (from 100 to 10,000 times higher than those reported for uncontaminated Mediterranean seawaters) testify to intense effects of anthropogenic impact on the harbour mainly related to the industrial and commercial activities carried out in the neighbouring area. The ensemble of the obtained results emphasizes the high potential of measurements of trace elements in the biogenic carbonates of benthic foraminifera as tracers of anthopogenic pollution of seawater and reliable proxies of potentially bioavailable forms (as free ions and/or more labile organic complexes) of seawater dissolved metals.

A ~2000 years long sedimentary record recovered from a gravity core on the eastern Tyrrhenian margin has been analysed by a multiproxy stratigraphic approach and provides a new sub-century paleoclimate time series of the central Mediterranean. Tephra layers of Vesuvius interbedded within the sampled succession and attributed to specific volcanic eruptions along with an AMS 14C dating of the core top have provided an accurate time framework for the studied record. Comparison of the Globorotalia inflata time series with the reconstructed Total Solar Irradiance (TSI) index and tree rings ?14C record, suggests a primary control of the insolation forcing on the planktonic foraminifera assemblage of the eastern Tyrrhenian Sea during the latest Holocene. In particular, the ~200 years (Suess cycles) and ~500 years oscillations attributed by several authors to solar activity were reliably recorded in the G. inflata time series, thus reinforcing the hypothesis that centennial fluctuations of solar intensity exert a primary control on the Mediterranean planktonic assemblage distribution.

The Oligocene represents an important time period from a wide range of perspectives and includes significant climatic and eustatic variations. The pelagic succession of the Umbria-Marche Apennines (central Italy) includes a complete and continuous sequence of marly limestones and marls, with volcaniclastic layers that enable us to construct an integrated stratigraphic framework for this time period. We present here a synthesis of detailed biostratigraphic, magnetostratigraphic, and chemostratigraphic studies, along with geochronologic results from several biotite-rich volcaniclastic layers, which provide the means for an accurate and precise radiometric calibration of the Oligocene time scale. From this study, the interpolated ages for the Rupelian/Chattian stage boundary, located in the upper half of Chron 10n at meter level 188 in the Monte Cagnero section, and corresponding to the O4/O5 planktonic foraminiferal zonal boundary, are 28.36 Ma (paleomagnetic interpolation), 28.27 +/- 0.1 Ma (direct radioisotopic dating), and 27.99 Ma (astrochronological interpolation). These ages appear to be slightly younger than those reported in recent chronostratigraphic time scale compilations. The Monte Cagnero section is a potential candidate for defining the Chattian Global Stratotype Section and Point (GSSP) and some reliable criteria are here proposed for marking the Rupelian/Chattian boundary according to International Union of Geological Sciences (IUGS) recommendations.

The objective of this study was to investigate correlates of risk for having microalbuminuria in individuals with one or more cardiovascular risk factors.The study involved 1919 individuals who attended general practice settings, were aged 55 to 75 yr, and did not have a history of cardiovascular events or diabetes but had one or more cardiovascular risk factors. A tree-based regression technique and multivariate analysis were used to identify distinct, homogeneous subgroups of patients with different likelihood of having microalbuminuria; interaction between correlates of microalbuminuria and risk for microalbuminuria was also investigated.The prevalence of microalbuminuria was 5.9%. Patients who did not have hypertension and had postload glycemia140 mg/dl showed the lowest prevalence of microalbuminuria (1.9%) and represented the reference class. The likelihood of microalbuminuria was seven times higher in men with hypertension and homeostatic model assessment levels in the upper tertile and four times higher in women with the same characteristics. Individuals with hypertension and lower homeostatic model assessment levels and normotensive individuals with postload glycemiaor = 140 mg/dl had a more than three-fold increased likelihood of having microalbuminuria. Treatment with statins was associated with a 54% reduction in the likelihood of having microalbuminuria, whereas levels of triglycerides150 mg/dl and fibrinogen levels in the upper tertile were associated with a significantly higher risk for microalbuminuria.The likelihood of having microalbuminuria in a population-based study of elderly individuals is strongly related to the interaction between the components of the metabolic syndrome, particularly hypertension, insulin resistance, and impaired glucose tolerance.

The concentrations of Rare Earth Elements and yttrium (REY) were measured in dissolved phase, in suspended particulate matter (SPM) and in sediments in seven sampling stations in the Mae Klong estuarine system (Inner Thailand Gulf) in order to study their behaviour and distribution pattern. The analysed samples generally show high Rare Earth Element (REE) content in the dissolved phase, with high Medium Rare Earth Elements (MREEs) and Yenrichments in the shale-normalized pattern (versus PAAS). These chemical features are interpreted in terms of direct influences of weathering processes of REE-rich minerals (e.g., phosphates), which abundantly out-crop in the Mae Klong watershed. These large MREE enrichments also suggest that dissolved sulphate complexes play an important role in the dissolved REE fate close to the marine coastal system. The shale normalized REEs and Y/Ho ratios additionally indicate a direct REY co-precipitation with Fe-oxyhydroxides along the river path and consequent adsorption, as coating, onto FeOOH surfaces. The REY behaviour in SPM appears strongly influenced by Al, Fe and Mn content, suggesting that the formation of an authigenic Fe, Mn oxyhydroxides and aluminosilicate particulate leads to REY adsorption and/or co-precipitation. The observed variations in the Y/Ho ratios suggest that different YeHo fractionation processes take place in the studied estuarine system. Strong similarities among chondrite-normalized REE patterns in both sediments and granitic rocks out-cropping in the surrounding regions suggest a generic relationship between the two groups of materials.

The Naples’s harbour is one of the largest and most important commercial and tourist port of the Mediterranean basin. It is located on the southeast coast of Italy and receives industrial and municipal wastewaters from the city of Naples. Due to its social and economic impact, a comprehensive assessment of levels and sources of contamination of bottom sediments in this area of the Mediterranean basin is essential to identify potential danger due to mobilization of contaminants produced by managing of the same sediments. In this study, superficial sediments collected from 189 sampling sites were analyzed for grain size, heavy metals (Cr, Cu, Ni, Pb, V, Zn, Co, Sn, Cd, Hg, As, Al and Fe), 16 priority polycyclic aromatic hydrocarbons (PAHs) and perylene and 38 individual polychlorinated biphenyl (PCB) congeners. Compared to the estimated local background, Cu, Zn, Pb, Cd, Sn and Hg show enrichment factors >3 and only Hg evidences a median value higher than theNOAA(effects range median) guidelines. Principal component analysis allowed us to clearly discriminate two areas mainly affected by heavy metals contamination and influenced by different sources related to industrial, commercial and/or urban activities. Priority PAHs are predominantly represented by three-five-ring compounds with concentrations ranging between 9 and 31774 ng g-1 and frequently higher than the NOAA ER-M index. A prevalent pyrolitic origin of PAH was assessed on the basis of the relative abundance of the different congeners and selected isomer ratios. The concentrations of PCBs, as sum of the 38 congeners, ranged from 1 to 899 ng g-1, with a predominance of highly chlorinated (tetra- and penta-chlorobiphenyls) congeners. WHO-TEQ values, calculated for the PCDD-like PCB congeners, suggest a relatively high level of toxicity. Generally, the concentration of PAHs and PCBs were higher near the sites of intense industrial, shipping and/or commercial activities suggesting a direct influence of these sources on the pollutant distribution patterns.

A high-resolution pelagic bulk carbonate stable isotope record from a central Tethyan lower Cretaceous composite section is presented. Three well-exposed sedimentary sequences (Chiaserna Monte Acuto, Bosso, and Gorgo a Cerbara sections, central Italy) cropping out throughout the Maiolica Formation were correlated by a detailed magnetostratigraphy, lithostratigraphy, and calcareous plankton biostratigraphy in order to reconstruct a continuous composite record from the middle Berriasian to the lower Aptian. The integrated stratigraphy of the three sequences provided an accurate time framework for the new high-resolution C isotope curve which is presented in this study. The composite ´ 13C signal, recorded in the depth domain, was analyzed by combined Lomb-Scargle periodogram and weighted wavelet Z transform (WWZ) – weighted wavelet amplitudes (WWA) Foster wavelet spectral methodologies, both appropriate for unevenly sampled curves. These tools allowed us to unravel the main frequencies modulating the record and their hypothetical shift in depth, respectively. The long-term

A high-resolution quantitative analysis of the calcareous planktonic assemblages (planktonic foraminifers and calcareous nannofossils) at the Punta Piccola section (at the base of which, the global standard stratotype-section and point of the Piacenzian stage is defined) provided a more accurate biostratigraphy for the Mediterranean middle Pliocene (2.6–3.6 Ma). In particular, an astronomically calibrated age of 2.87 Ma was estimated for the Pliocene first occurrence of Neogloboquadrina atlantica instead of the younger previously proposed age of 2.72 Ma. Spectral analysis performed on the Globigerinoides species (spp.) planktonic foraminifera assemblage along with cross-spectral analysis between the same record and the astronomic target curve La(041,1) calculated for the summer season (June–July) at 65°N provided solid evidence that the Globigerinoides spp. group of planktonic species is a reliable recorder of orbital forcing and can be appropriately used for astronomical tuning of marine sedimentary records. The same procedures of spectral analysis were applied to the individual species that constitute the Globigerinoides spp. group (G. ruber, G. obliquus, and G. quadrilobatus), thus resolving their different frequency structures and species-specific response to the different astronomic periodicities. Whereas G. obliquus and G. quadrilobatus appear primarily controlled by precession, G. ruber is largely forced by obliquity. Small ecological differences, mainly related to dissimilar food quality requirements, were assumed to distinctively control the time distribution of the two groups of species. Precessionally forced oligotrophic conditions in the surface Mediterranean waters, induced by summer continental runoff, led to a dominance of copepods-based dietary, typical of G. quadrilobatus. Conversely, obliquity cycles drove the abundance distribution of G. ruber in the sea surface waters of the Mediterranean, influencing the sea surface temperature, light intensity, and/or phytoplankton distribution. Sub-Milankovitch periodicities (cycles

A geochemical survey of the northwestern part of the Thailand Gulf (Inner Gulf) was carried out in order to define concentrations and distribution patterns of selected heavy metals (V, Cr, Co, Ni, Cu, Zn, and U) in the coastal system and estuarine area of the Mae Klong river. The results indicate the presence of two different sources of heavy metals in the studied environment and allowed us to identify a lithogenic component that significantly influences the composition of coastal waters and suspended particulate matter (SPM). Comparison of the normalized heavy metals concentrations both in the studied samples and in those reported for the Sn–W ores present in the surrounding areas suggests an important anthropogenic contribution to the chemistry of the seafloor sediments. Vanadium and nickel enrichment factors (EF) calculated for coastal waters indicate that contamination by hydrocarbons discharge took place in the investigated area.

We present an astronomically tuned polarity timescale for the late Eocene/early Oligocene based on a cyclic limestone/marls sedimentary succession exposed at Massignano, Italy (GSSP for the Eocene-Oligocene boundary). Here we applied spectral analysis techniques to the high-resolution magnetic susceptibility record. The results provide clear evidence of a regular and cyclic signal that allows us to discard a stochastic mechanism as controlling these fluctuations. Conversely, these outcomes reveal the presence of stable and notable periodicities that are in tune with those associated with orbital forcing. Through a cyclostratigraphic analysis of the rhythmic sedimentary alternations and combination with the results of time series analysis of the proxy record, we refine the late Eocene portion of the GPTS. Through astronomical tuning of the rhythmic sedimentary alternations to recent astronomically calculated variations of Earth's orbit we recalibrated the polarity boundaries ages and the main stratigraphic events recognized throughout the sedimentary record. Among these, an age of 33.714 Ma is proposed for the E/O boundary.

The concentration of rare-earth elements and yttrium (REY) was investigated in dissolved phase, suspended particulate matter, and seafloor sediments of the western coastal area of the Gulf of Thailand. The samples show Eu and Gd positive anomalies in the shale-normalized REY patterns, especially in the suspended particulate matter. On the other hand, a very high REE content was detected in the coastal waters, probably due to the weathering produced by the Mae Klong river waters on rare-earth element (REE)-rich accessory minerals coming from terrains and mineral deposits cropping out in the studied area. The shale-normalized patterns of yttrium and REE estimated for the dissolved phase show an enrichment of medium rare-earth elements (MREE), characteristic of extensive water-rock interactions and weathering occurring in the continental environment. The REE concentrations of suspended particulate, normalized to the REE concentrations in each sediment sampled from the tidal flat, show the same behaviour of the experimentally determined apparent REE bulk distribution coefficients [1] for pH values ranging from about 5.5 to 6.2. Since the REY concentration of the water masses is controlled by the oceanographic features of the studied area, riverine inputs, and ionic straight, we suppose that the dissolved phase represents a mix of truly dissolved and colloidal pool (< 0.2 mu m) in which REY were enriched during the rock-water interactions of continental environment. In the estuarine system, the salt-induced coagulation of colloidal pool takes place and an authigenic fraction of suspended matter is formed, assuming the typical REE behaviour due to rock-water interactions.