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51.
Induction of cytochrome P4501A in fish is a well-known indicator of exposure to polycyclic aromatic hydrocarbons (PAHs) and determination of PAH metabolites in bile by fixed wavelength fluorescence (FF) or synchronous fluorescence spectroscopy (SFS), has become an useful method in monitoring programs. In this work the relationship between cytochrome P4501A (EROD activity) and levels of biliary PAH metabolites was measured in the European eel Anguilla anguilla, in both field and laboratory conditions: organisms were sampled on a seasonal basis from the Orbetello lagoon (Tuscany) to characterize the natural variability of these biological parameters, while in laboratory eels were intraperitoneally injected with benzo[a]pyrene to investigate temporal and dose-dependent induction patterns. Results showed that induction of cytochrome P450 and accumulation of PAHs metabolites in bile are not necessarily correlated either in field, or in laboratory investigations; different seasonal changes were measured in natural conditions and slight variations in dose and time response patterns were also obtained in laboratory exposures. 相似文献
52.
Induction of cytochrome P4501A in fish is a well-known indicator of exposure to polycyclic aromatic hydrocarbons (PAHs) and determination of PAH metabolites in bile by fixed wavelength fluorescence (FF) or synchronous fluorescence spectroscopy (SFS), has become an useful method in monitoring programs. In this work the relationship between cytochrome P4501A (EROD activity) and levels of biliary PAH metabolites was measured in the European eel Anguilla anguilla, in both field and laboratory conditions: organisms were sampled on a seasonal basis from the Orbetello lagoon (Tuscany) to characterize the natural variability of these biological parameters, while in laboratory eels were intraperitoneally injected with benzo[a]pyrene to investigate temporal and dose-dependent induction patterns. Results showed that induction of cytochrome P450 and accumulation of PAHs metabolites in bile are not necessarily correlated either in field, or in laboratory investigations; different seasonal changes were measured in natural conditions and slight variations in dose and time response patterns were also obtained in laboratory exposures. 相似文献
53.
Measurements and Parametrizations of the Atmospheric Boundary-Layer Height at Dome C,Antarctica 总被引：2，自引：2，他引：0
Ilaria Pietroni Stefania Argentini Igor Petenko Roberto Sozzi 《Boundary-Layer Meteorology》2012,143(1):189-206
An experimental campaign, Study of the Atmospheric Boundary Layer Environmental at Dome C, was held during 2005 at the French-Italian
station of Concordia at Dome C. Ground-based remote sensors, as well as in situ instrumentation, were used during the experimental
campaign. The measurements allowed the direct estimation of the polar atmospheric boundary-layer height and the test of several
parametrizations for the unstable and stable boundary layers. During the months of January and February, weak convection was
observed while, during the polar night, a long-lived stable boundary layer occurred continuously. Under unstable stratification
the mixing-layer height was determined using the sodar backscattered echoes and potential temperature profiles. The two estimations
are highly correlated, with the mixing height ranging between 30 and 350 m. A simple prognostic one-dimensional model was
used to estimate the convective mixing-layer height, with the correlation coefficient between observations and model results
being 0.66. The boundary-layer height under stable conditions was estimated from radiosounding profiles as the height where
the critical Richardson number is reached; values between 10 and 150 m were found. A visual inspection of potential temperature
profiles was also used as further confirmation of the experimental height; the results of the two methods are in good agreement.
Six parametrizations from the literature for the stable boundary-layer height were tested. Only the parametrization that considers
the long-lived stable boundary layer and takes into account the interaction of the stable layer with the free atmosphere is
in agreement with the observations. 相似文献
54.
Stefania Da Pelo Elodia Musu Rosa Cidu Franco Frau Pierfranco Lattanzi 《Journal of Geochemical Exploration》2009,100(2-3):142-152
The Furtei gold mine in Sardinia (Italy) exploits a volcanic-hosted high-sulphidation epithermal deposit. Large amounts of materials derived from exploitation are present in open pits, waste rock dumps and cyanidation tailings impoundment. Mineralized rocks in outcrops and waste dumps contain significant amounts of sulphides (mainly pyrite and enargite). These materials have a high potential for acid drainage generation and release of toxic elements (notably Cu and As, but also Al, Ni, Co and Cd) as pointed out by laboratory leaching tests and in agreement with chemical composition of waters draining the mining area, that show pH as low as 2, up to 180 mg/L Cu, up to 5 mg/L As, and up to 788 mg/L Al. On the other hand, leaching solutions and waters interacting with mineral assemblages of the propylitic alteration zone (mainly composed of chlorite, quartz, and calcite, with relic magmatic plagioclase) show higher pH, and lower metal loads. Leachates from cyanidation tailings show variable pH (between 6.2 and 9.7, depending on sulphide content in tailings); cyanide concentration varies between 110 µg/L and about 3 mg/L, whereas contents of toxic elements in leachates are, with the exception of Hg, within the limits of Italian regulations for non-dangerous industrial wastes. Reclamation plans provide for confinement of tailings within specific repositories. This measure should effectively reduce the environmental impact of these materials. Reclamation plans should also include an adequate management of other high-sulphide wastes. 相似文献
55.
Alberto De Bonis Stefania Febbraro Chiara Germinario Daniela Giampaola Celestino Grifa Vincenza Guarino Alessio Langella Vincenzo Morra 《Geoarchaeology》2016,31(6):437-466
Recent transportation infrastructure works in Naples, Italy, provided important discoveries related to the production of pottery in the Hellenistic workshop area of Piazza Nicola Amore. A minero‐petrographic investigation was conducted on 35 samples belonging to the widespread Campana A ware and production indicators (clayey raw materials, unfired Graeco‐Italic amphorae, kiln wastes, workshop tools). Additional analysis was conducted on black‐glaze and common ware samples for comparison. The analyses reveal compositional and technological homogeneity of Campana A ware. Samples are characterized by low CaO content with evidence of both volcanic and sedimentary components, suggesting that different clay sources were properly mixed to prepare a standard recipe. Production indicators, black‐glaze and common wares, have a composition well consistent with the calcareous clays from the island of Ischia. Leucite‐ and garnet‐bearing temper from the Somma Volcano were used for the preparation of coarse‐grained pastes, unfired Graeco‐Italic amphorae, and clayey raw materials, thus suggesting that they represented the clay sources for amphorae production. Our results reveal new technological and socioeconomic aspects of Hellenistic pottery production in the Bay of Naples, in particular for the Campana A ware, now representing a new reference group: Neapolis. 相似文献
56.
Relative contribution of foliar and fine root pine litter to the molecular composition of soil organic matter after in situ degradation 总被引：1，自引：0，他引：1
Stefania Mambelli Jeffrey A. Bird Gerd Gleixner Todd E. Dawson Margaret S. Torn 《Organic Geochemistry》2011,42(9):1099-1108
The influence of litter quality on soil organic matter (SOM) stabilization rate and pathways remains unclear. We used 13C/15N labeled litter addition and Curie-point pyrolysis gas chromatography–mass spectrometry combustion-isotope ratio mass spectrometry (Py–GC–MS–C–IRMS) to explore the transformation of litter with different composition and decay rate (ponderosa pine needle vs. fine root) to SOM during 18 months in a temperate conifer forest mineral (A horizon) soil. Based on 13C Py–GC–MS–C–IRMS the initial litter and bulk soil had ∼1/3 of the total pyrolysis products identified in common. The majority was related either to carbohydrates or was non-specific in origin. In bulk soil, carbohydrates had similar levels of enrichment after needle input and fine root input, while the non-specific products were more enriched after needle input. In the humin SOM fraction (260 yr C turnover time) we found only carbohydrate and alkyl C-derived compounds and greater 13C enrichment in the “carbohydrate” pool after fine root decomposition. 15N Py–GC–MS–C–IRMS of humic substances showed that root litter contributed more than needle litter to the enrichment of specific protein markers during initial decomposition.We found little evidence for the selective preservation of plant compounds considered to be recalcitrant. Our findings suggest an indirect role for decomposing plant material composition, where microbial alteration of fine root litter seems to favor greater initial stabilization of microbially derived C and N in SOM fractions with long mean turnover times, such as humin, compared to needles with a faster decay rate. 相似文献
57.
Degli Abbati Stefania Morandi Paolo Cattari Serena Spacone Enrico 《Bulletin of Earthquake Engineering》2022,20(4):2187-2217
Bulletin of Earthquake Engineering - This paper presents the comparison of the results of modal and nonlinear analyses carried out on a 2-story masonry building with rigid diaphragms, inspired by... 相似文献
58.
Leonardo Casini Matteo Maino Antonio Langone Giacomo Oggiano Stefania Corvò Joan Reche Estrada Montserrat Liesa 《Journal of Metamorphic Geology》2023,41(1):25-57
The Variscan high-grade metamorphic basement of northern Sardinia and southern Corsica record lower Carboniferous anatexis related to post-collisional decompression of the orogen. Migmatites exposed in the Punta Bianca locality (Italy) consist of quartz + biotite + plagioclase + K-feldspar orthogneisses, garnet and cordierite-bearing diatexite and metatexites, derived from metasediments. Field evidence, petrographic observations, ELA-ICP-MS zircon and monazite dating and pseudosection modelling suggest that anatexis was apparently episodic involving two main stages of partial melting. Using pseudosection modelling, we infer that the first stage of partial melting is in the upper amphibolite facies (~0.45 GPa at ~740°C). Cordierite overgrowths replacing sillimanite, combined with the composition of plagioclase and K-feldspar, suggest decompression followed cooling below the solidus at low pressures of ~0.3 GPa. The age of the first anatectic event is not precisely constrained because of extensive resetting of the isotopic systems during the second melting stage, yet few zircons preserve a lower Carboniferous age which is consistent with the regional dataset. This lower Carboniferous migmatitic fabric is offset by a network of pseudotachylyte-bearing faults suggestive of cooling to greenschist facies conditions. Garnet/cordierite-bearing diatexites incorporate fragments of pseudotachylite-bearing orthogneiss and metatexites. Pseudosection modelling indicates nearly isobaric re-heating up to ~750°C, followed by further cooling below the solidus. The inferred P–T path is consistent with decompression and cooling of the Variscan crust through post-collisional extension and collapse of the thickened orogenic crust, followed by nearly isobaric re-heating at low pressures (~0.3 GPa) yielding to a second melting stage under LP-HT conditions. U/Th-Pb monazite ages for diatexite migmatites indicate an upper bound of 310–316 Ma for the second melting stage, suggesting that the second melting stage is coincident with the regional phase of crustal shearing. The cause of the high geothermal gradient required for re-heating during the second melting stage is unknown but likely requires some heat source that was probably related to dissipation of mechanical work within crustal-scale shear zones. According to this interpretation, some upper Carboniferous peraluminous granite precursors of the Corsica–Sardinia Batholith could be the outcome rather than the cause of the late-Variscan high-T metamorphism. 相似文献
59.
60.
Ecotoxicological and human health risk in a petrochemical district of southern Italy 总被引：2，自引：0，他引：2
Ausili A Gabellini M Cammarata G Fattorini D Benedetti M Pisanelli B Gorbi S Regoli F 《Marine environmental research》2008,66(1):215-217
An ecotoxicological investigation has been carried in the petrochemical district of Priolo (Sicily, Italy), one of the largest in Europe. Results indicated a severe mercury contamination in sediments sampled near a chloro-alkali plant. A clear bioavailability of this element was demonstrated in mussels Mytilus galloprovincialis (both native and translocated) and the benthic fish Mullus barbatus, which also exhibited marked genotoxic damages. The elevated mercury concentrations in marine organisms are a serious concern for human health; according to the national average fish consumption, the provisional tolerable weekly intake (PTWI) of Hg would be easily exceeded by at least 4 to 12 fold. Such toxicological risk is of particular importance for pregnant women, being possibly involved in the elevated frequency of neonatal malformations. 相似文献