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Fossi MC Marsili L Neri G Natoli A Politi E Panigada S 《Marine pollution bulletin》2003,46(8):972-982
In the Mediterranean Sea, top predators, and particularly cetacean odontocetes, accumulate high concentrations of organochlorine contaminants and toxic metals, incurring high toxicological risk. In this paper we investigate the use of the skin biopsies as a non-lethal tool for evaluating toxicological hazard of organochlorines in Mediterranean cetaceans, presenting new data 10 years after the paper published by Fossi and co-workers [Mar. Poll. Bull. 24 (9) (1992) 459] in which this new methodology was first presented. Some organochlorine compounds, now with worldwide distribution, are known as endocrine disrupting chemicals (EDCs). Here the unexplored hypothesis that Mediterranean cetaceans are potentially at risk due to organochlorines with endocrine disrupting capacity is investigated. High concentrations of DDT metabolites and PCB congeners (known as EDCs) were found in the different Mediterranean species (Stenella coeruleoalba, Delphinus delphis, Tursiops truncatus and Balaenoptera physalus). In this paper we also propose benzo(a)pyrene monooxygenase (BPMO) activity in marine mammal skin biopsies (non-lethal biomarker) as a potential indicator of exposure to organochlorines, with special reference to the compounds with endocrine disrupting capacity. A statistically significant correlation was found between BPMO activity and organochlorine levels (DDTs, pp(')DDT, op(')DDT, PCBs and PCB99) in skin biopsies of males of B. physalus. Moreover a statistical correlation was also found between BPMO activity and DDT levels in skin biopsies of the endangered Mediterranean population of D. delphis. These results suggest that BPMO induction may be an early sign of exposure to organochlorine EDCs and can be used for periodic monitoring of Mediterranean marine mammal toxicological status. 相似文献
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Felice Arena Alfredo Ascanelli Vincenzo Nava Diego Pavone Alessandra Romolo 《Coastal Engineering》2008,55(12):1052-1061
High waves at ocean occur during a complex space–time evolution of wave groups. In this paper the nonlinear structure of three-dimensional sea wave groups at intermediate water depth is investigated. To this purpose, the Boccotti's Quasi-Determinism theory is firstly applied to describe the linear wave groups when a given exceptionally high crest occurs. Then, the second-order correction to the linear solution is derived for the general condition of three-dimensional wave groups, at a finite water depth. Several numerical applications, finally, have been carried out in order to show how both the spectral bandwidth and the directional spreading modify the nonlinear high waves at different water depth. 相似文献
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Giovanni Bearzi Arianna Azzellino Elena Politi Marina Costa Mauro Bastianini 《Ocean Science Journal》2008,43(4):175-182
Bottlenose dolphins are the only cetaceans regularly observed in the northern Adriatic Sea, but they survive at low densities
and are exposed to significant threats. This study investigates some of the factors that influence habitat use by the animals
in a largely homogeneous environment by combining dolphin data with hydrological and physiographical variables sampled from
oceanographic ships. Surveys were conducted year-round between 2003 and 2006, totalling 3,397 km of effort. Habitat modelling
based on a binary stepwise logistic regression analysis predicted between 81% and 93% of the cells where animals were present.
Seven environmental covariates were important predictors: oxygen saturation, water temperature, density anomaly, gradient
of density anomaly, turbidity, distance from the nearest coast and bottom depth. The model selected consistent predictors
in spring and summer. However, the relationship (inverse or direct) between each predictor and dolphin presence varied among
seasons, and different predictors were selected in fall. This suggests that dolphin distribution changed depending on seasonal
forcing. As the study area is relatively uniform in terms of bottom topography, habitat use by the animals seems to depend
on complex interactions among hydrological variables, caused primarily by seasonal change and likely to determine shifts in
prey distribution. 相似文献
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The study of Mars linked to its climatic history, the presence of water and possible forms of life on the planet, are becoming more and more important in recent years. In this paper we present laboratory reflection measurements on olivine samples which are believed to be the product of alteration induced by their coexistence with water. The reflection spectra have been obtained in the wavelength range from 0.2 to and for different grain sizes; they exhibit, among various bands, some of which due to H2O and OH-, a characteristic absorption feature at about , whose emission wings at 0.56 and near have relative strengths which are size dependent and well correlated. The identification of such feature in the observed spectra of Mars would provide useful information about the grain size of the Martian regolith and, in association with other bands, also about the possible presence of olivine altered by water in the past. 相似文献
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Dr. Romolo Romano 《International Journal of Earth Sciences》1968,57(3):773-783
The author presents 32 new analyses of volcanites from Pantelleria and draws some magmatological and geochemical conclusions.
Dedicated to Professor Dr. A.Rittmann on the occasion of his 75. birthday 相似文献
Zusammenfassung Der Autor gibt 32 neue Analysen von Vulkaniten von Pantelleria bekannt und zieht daraus einige magmatologische und geochemische Schlußfolgerungen.
Résumé L'auteur présente 32 analyses nouvelles de roches volcaniques de l'île de Pantelleria et en tire des conclusions d'ordre magmatologique et géochimique.
Riassunto Nella presente nota, l'Autore riporta 32 nuove analisi di vulcaniti di Pantelleria traendone delle conclusioni di carattere magmatologico e geochimico.
32 Pantelleria. , .
Dedicated to Professor Dr. A.Rittmann on the occasion of his 75. birthday 相似文献
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Alessandra Romolo Giovanni Malara Giuseppe Barbaro Felice Arena 《Applied Ocean Research》2009,31(1):31-36
This paper deals with the random forces produced by high ocean waves on submerged horizontal circular cylinders. Arena [Arena F, Interaction between long-crested random waves and a submerged horizontal cylinder. Phys Fluids 2006;18(7):1–9 (paper 076602)] obtained the analytical solution of the random wave field for two dimensional waves by extending the classical Ogilvie solution [Ogilvie TF, First- and second-order forces on a cylinder submerged under a free surface. J Fluid Mech 1963;16:451–472; Arena F, Note on a paper by Ogilvie: The interaction between waves and a submerged horizontal cylinder. J Fluid Mech 1999;394:355–356] to the case of random waves. In this paper, the wave force acting on the cylinder is investigated and the Froude Krylov force [Sarpkaya T, Isaacson M, Mechanics of wave forces on offshore structures, Van Nostrand Reinhold Co.; 1981], on the ideal water cylinder, is calculated from the random incident wave field. Both forces represent a Gaussian random process of time. The diffraction coefficient of the wave force is obtained as quotient between the standard deviations of the force on the solid cylinder and of the Froude Krylov force. It is found that the diffraction coefficient of the horizontal force Cdo is equal to the Cdv of the vertical force. Finally, it is shown that, since a very large wave force occurs on the cylinder, it may be calculated, in time domain, starting from the Froude Krylov force. It is then shown that this result is due to the fact that the frequency spectrum of the force acting on the cylinder is nearly identical to that of the Froude–Krylov force. 相似文献
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Paolo Boccotti Felice Arena Vincenzo Fiamma Alessandra Romolo Giuseppe Barbaro 《Ocean Engineering》2011,38(2-3):509-518
A method for obtaining the directional spectrum, on assuming that the frequencies of the elementary waves are all different from one another, is re-proposed in a form suitable for applications to sea states near a coast. The method is applied to an interval of 10 h during which the sea state remained basically steady state off the beach at Reggio Calabria (east coast of the Straits of Messina). It is shown that the directional spectrum converges as the length of the time series data grows. A numerical simulation of a 10 h sea state confirms that the directional spectrum converges as the length of the time series grows, and the convergence is onto the known directional spectrum used to make the numerical simulation. Through the numerical simulation, it is proved that the method, generally, is suitable for applications even with short time series of wind waves (duration of about 100Tp). Finally, it is shown that the method is not necessarily inadequate even with short records of multimodal sea states with different modal directions, modal amplitude ratios and intermodal distances. 相似文献
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D. Sidiras D. Politi F. Batzias N. Boukos 《International Journal of Environmental Science and Technology》2013,10(6):1337-1348
In this work, a low-cost lignocellulosic adsorbent with high biosorption capacity is proposed, suitable for the efficient removal of hexavalent chromium from water and wastewater media. The adsorbent was produced by autohydrolyzing Scots Pine (Pinus Sylvestris) sawdust. The effect of the autohydrolysis conditions, i.e., pretreatment time and temperature, on hexavalent chromium biosorption was investigated using energy-dispersive X-ray spectroscopy (EDS) and UV–visible spectrophotometry. The Freundlich, Langmuir, Sips, Radke-Prausnitz, Modified Radke-Prausnitz, Tóth, UNILAN, Temkin and Dubinin-Radushkevich adsorption capacities and the rate constant values for pseudo-first- and pseudo-second-order kinetics indicated that the autohydrolyzed material exhibits significantly enhanced hexavalent chromium adsorption properties comparing with the untreated sawdust. The Freundlich’s adsorption capacity K F increased from 2.276 to 8.928 (mg g?1)(L mg?1)1/n , and the amount of hexavalent chromium adsorbed at saturation (Langmuir constant q m) increased from 87.4 to 345.9 mg g?1, indicating that autohydrolysis treatment at 240 °C for 50 min optimizes the adsorption behavior of the lignocellulosic material. 相似文献
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