105,641 research outputs found
Luciani In amorem carmina heroica
No full text[100] h. ; 4o.El autor del "Palinurus, vel De foelicitate et miseria dialogus" es Maffeo Veggio. "Luciani In amorem carmina" o "Heroica", es obra poética del Pseudo-Luciano. El "Scipio" se conoce mejor en latín como el "Dialogus mortuorum XII" de Luciano de Samosata. -- Carece de la Vita Luciani anunciada en port. -- El trad. de los diálogos Panos & Mercurii y del Panope & Galene, añadidos al final, es Pontico Virunio.Datos del imp. tomados del colofónSign.: a-m8, n4. -- En bl. la última h. -- Error de sign.: la h. a4 signaturizada b4. -- Texto a línea tirada. -- L. red.Inic. xil
Ecological and evolutionary response of Tethyan planktonic foraminifera to the middle Eocene climatic optimum (MECO) from the Alano section (NE Italy)
No full textThe enigmatic middle Eocene climatic optimum (MECO) is a transient (~500kyr) warming event that significantly interrupted at ~40 Ma the long-term cooling through the middle and late Eocene, eventually resulting in establishment of permanent Antarctic ice-sheet. This event is still poorly known and data on the biotic response are so far scarce. Here we present a detailed planktonic foraminiferal analysis of the MECO interval from a marginal basin of the central-western Tethys (Alano section, northeastern Italy). The expanded and continuous Alano section provides an excellent record of this event and offers an appealing opportunity to better understand the role of climate upon calcareous plankton evolution. A sapropel-like interval, characterized by excursions in both the carbon and oxygen bulk-carbonate isotope records, represents the lithological expression of the post-MECO event in the study area and follows the δ18O negative shift, interpreted as representing the MECO warming.High-resolution quantitative analysis performed on both >38 μm and >63 μm fractions reveals pronounced and complex changes in planktonic foraminiferal assemblages indicating a strong environmental perturbation that parallels the variations of the stable isotope curves corresponding to the MECO and post-MECO intervals. These changes consist primarily in a marked increase in abundance of the relatively eutrophic subbotinids and of the small, low-oxygen tolerant Streptochilus, Chiloguembelina and Pseudohas-tigerina. At the same time, the arrival of the abundant opportunist eutrophic Jenkinsina and Pseudoglobigerinella bolivariana, typical species of very high-productivity areas, also occurs. The pronounced shift from oligotrophic to more eutrophic, opportunist, low-oxygen tolerant planktonic foraminiferal assemblages suggests increased nutrient input and surface ocean productivity in response to the environmental perturbation associated with the MECO. Particularly critical environmental conditions have been reached during the deposition of the sapropel-like beds as testified by the presence of common giant and/or odd morphotypes. This is interpreted as evidence of transient alteration in the ocean chemistry.The enhanced surface water productivity inferred by planktonic foraminiferal assemblages at the onset of the event should have resulted in heavier δ13C values. The recorded lightening of the carbon stable isotope preceding the maximum warmth therefore represents a robust indication that it derives principally by a conspicuous increase of pCO2. The increased productivity of surface waters, also supported by geochemical data, may have acted as mechanism for pCO2 reduction and returned the climate system to the general Eocene cooling trend. The oxygen-depleted deep waters and the organic carbon burial following the peak of the MECO event represent the local response to the MECO warming and suggest that high sequestration of organic matter, if representing a widespread response to this event, might have contributed to the decrease of pCO2 as well. Though the true mechanisms are still obscure, several lines of evidence indicate a potential pressure on planktonic foraminiferal evolution during the MECO event including permanent changes besides transient and ecologically controlled variations
Luciani Samosatensis Colloquia selecta & timon. Cebetis Thebani sententiae morales grade et latine ; Colloquia Luciani & Timonem notis illustravit
No full textSign.: [cruz latina]\p3\s, A-G\p12\s ; A-G\p12\s, H\p3\s, *-5*\p12\s, 6*\p8\sPort. a dos tintasPort. con viñeta xilError de pag., de p. 72 pasa á p. 75La h. de grab. calc. alegóricaLa h. de grab. pleg. calc. representa monedasLuciani Dialogi mortuorum, 173 p., con sign. propia. Ad Luciani Dialogos notae, 122 p. con sign. propi
H πρόσληψη του Αριστοδήμου του Βιτσέντσο Μόντι στην Ελλάδα
No full textL’Aristodemo fu composto tra il 1784 e il 1786, anno in cui l'opera fu pubblicata e presentata in scena. La rappresentazione, a cui l'autore stesso prese parte, fu data in palazzi aristocratici dell'alta società romana. Il famoso poeta tedesco Goethe, che fu sorpreso dal fatto che il suicidio di Aristodemo sulla scena era contrario alla tradizione del teatro tragico italiano. In questo studio si esamina la fortuna di quest’opera in Grecia
An age-related model derived from ICRP 67 for plutonium dose calculation: Application to an updated case of contamination
No full textThe main innovative features of a new model developed for plutonium dose assessments are presented. The physiological assumptions and the improvement of model predictions for plutonium activity in biological samples are discussed. Preliminary results relating to dose calculations and sensitivity analysis are also presented. The model has been applied to a well documented case of contamination. This was the first opportunity to test the new features of the model in a practical case and to show how to apply sensitivity techniques to a complex data set of a contamination case
Albian high-resolution biostratigraphy and isotope stratigraphy: the Coppa della Nuvola section pelagic succession of the Gargano Promontory (Southern Italy)
No full textHigh-resolution δ13C and δ180 curves, calibrated against planktonic foraminiferal and calcareous nannofossil biostratigraphy, are provided for the upper Aptian–lower Cenomanian pelagic succession of the Gargano Promontory (Coppa della Nuvola section, southern Italy). The succession consists of two superimposed formations: the Marne a Fucoidi and the Scaglia (lower portion only). According to our integrated biostratigraphy,the entire succession spans the latest Aptian (planktonic foraminiferal T. bejaouaensis and calcareous nannofossil R. angustus Zones) and early Cenomanian stages (R. cushmani Zone CC9c). The Marne a Fucoidi–Scaglia transition falls in the late Albian (R. ticinensis Zone; CC9a+b Subzones). The high-resolution δ13C curve from the Coppa della Nuvola section can be subdivided into characteristic segments. Four negative shifts of δ13C are recorded, followedby increasing values in, respectively, the early Albian (C11, C12), the early late Abian (C14, C 15), the late Albian (C16, C17), and the early Cenomanian (C22). The late Albian carbon-isotope event, corresponding to the Oceanic Anoxic Event (OAE) 1d or Breistroffer Event, is possibly missing in the Coppa della Nuvola section as a result of condensation or erosion (C19–C20?). Even if, in the section studied, carbon-rich levels are not recorded (though some stratigraphic intervals are covered by Quaternary deposits in the lower portion), it is likely that the lower Albian (T. primula; P. columnata Zones) and the upper Albian (T. praeticinensis Subzone– R. subticinensis Zone; R. achlyostaurion Zone) positive δ13C peaks succeeding negative
trends in δ13C (C11–C12; C16–17) record the pattern of global carbon burial, documented in other areas of the Gargano Promontory and elsewhere and connected to the OAE1b and OAE1c. Some or all of the negative δ13C shifts may record the of isotopically light carbon into the ocean−atmosphere system from the dissociation of gas hydrates.
The δ18O curve of the Coppa della Nuvola section shows a similar trend to that of the δ13C curve. Although partly of diagenetic origin, the negative shifts in the early Albian, late Albian and early Cenomanian may be interpreted as records of warming events resulting from the introduction of methane and its oxidation product carbon dioxide into the atmosphere.
The palaeoceanographic conditions inferred by the biotic and isotopic changes suggest fluctuating meso-eutrophic conditions through the late-Aptian–early-middle Albian and increasingly stable oligotrophic situation starting from the late Albian interval. Two main possible episodes of increased eutrophy, suggested by pulses in radiolarian abundance and marked drop in foraminiferal diversity, occurred during the Albian and correlate with the above-mentioned positive carbon-isotope shifts and regional and supraregional accumulation of organic matter (OAE1b and OAE1c)
Foraminiferal, calcareous nannofossils and geochemical data in the Lower Cretaceous pelagic succession of the Gargano Promontory.
No full textUncertainty Analysis of the Urinary Excretion of Plutonium
No full textA quantitative estimate of the uncertainty of the urinary excretion of plutonium predicted by available biokinetic model is provided. Urinary excretion is primarily considered here because the monitoring of internal contamination of plutonium mainly relies on measurements of activity in urine samples. A previous paper has identified the most significant transfer rates far plutonium urinary excretion following an acute intake. This analysis is used here as a screening method to reduce the number of model parameters to be considered. A log-normal distribution was assumed far the probability distribution of the model parameters. The spread of the values, represented by the geometric standard deviation (GSD), is explicitly calculated, as few indications on the range of variation of systemic transfer rates are available. Different values far the GSD were considered. Assuming a certain GSD for all the systemic rate constants, random values of the rates were generated (by means of a Monte Carlo simulation with a Latin Hypercube Sampling scheme) and the resulting predictions of urine bioassay measurements were calculated. The comparison of the mean and variance of the predictions with the available data from several studies performed on different subjects provides information about the GSD of model parameters that represents the inter-subject variations of transfer parameters
Biotic and geochemical response to anoxic events: the Aptian pelagic succession of the Gargano Promontory (Southern Italy).
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