102,733 research outputs found
Prime riflessioni in merito alle nuove eccezioni relative agli appalti e le concessioni tra enti nell’ambito del settore pubblico, alla luce della vecchia giurisprudenza sull’in house
No full textRelazione nell'ambito della conferenza dal titolo Integrazione europea, servizi pubblici e diritti fondamentali.The article reproduces the speech at the seminar on the topic "European Integration, public services and fundamental rights", during which the Author has expressed some preliminary thoughts on the innovations introduced on the in-house requirements set by the new European Directives on public procurements. The seminar was organized by the Jean Monnet Chair of Prof. Emilio Castorina, which is focused on “public services, fundamental rights and European constitutionalism”, and took place in Catania, at the Department of Law (Villa Cerami) January 31, 2014
Homage to Gaetano Castorina
No full textRicordo dell'opera e della ricerca del Prof. Giuseppe G. Castorina"And to touch by his own example love and reverence to alla things tha God mad and loveth
Fe isotopic ratios in selected groundwater samples from the Ravenna and Friuli coastal plains, NE Italy and significance for the environment
No full textHigh Fe concentrations (from 1.34 to 12.72 mg/L) were measured by Pezzetta et al.(2011) in groundwater samples from the Lower Friulan Plain near the north Adriatic seacoast. The research has unveiled a positive correlation between Fe concentrations and groundwater salinization (0.9–19679 mg/L Cl) and a particularly wide range of d56Fe (from –5.3 to +2.15‰ relative to IRMM-14 international standard, Castorina et al., 2013), compared with literature data. Furthermore, a positive correlation between d56Fe and Fe concentrations has been found. The present study has investigated the relationship of Fe isotopic ratios to Fe and chloride concentrations in groundwater samples from the Ravenna Plain near the north Adriatic seacoast aimed at comparing the results with those obtained from the Friulan Plain area. Therefore, the following characteristics have been recognized: a) Ravenna groundwater displays a smaller isotopic range (d56Fe from –2.6 to 0‰) than
Friulan groundwater, b) unlike the positive correlation in Friulan groundwater, no correlation exists between d56 Fe and Fe concentrations (<0.02–3.13 mg/L) in Ravenna
groundwater, c) there is a positive correlation between
d56Fe and pH in Ravenna groundwater while there are negative or nil correlations in Friulian groundwater, and d) there is a negative correlation between d56Fe and chloride concentrations(55–16,800 mg/L) in Ravenna groundwater, while there are positive or nil correlations in Friulian groundwater. These different characteristics of groundwater from the two
coastal Plains likely reflect different processes taking place in the two sites despite the broadly similar environments. The particularly isotopic lighter Fe compositions of most of groundwater samples from the Friulan Plain have been explained by isotopic fractionation during repeated cycling of Fe precipitation. This multi-staged process apparently does not significantly operate in the Ravenna Plain, where groundwater
generally contains much lower Fe concentrations, suggesting that redox conditions arecomparatively less exasperated. The low Fe concentrations may also explain the lack of any correlation with d56Fe as well as the positive correlation between d56Fe and pH in groundwater from the Ravenna Plain. Lastly, the negative correlation between d56Fe and Cl in Ravenna groundwater indicates that with increasing salinization, there is likely precipitation of 56 Fe-rich ferrihydrite, thus leaving groundwater 56Fe-poor. In contrast, in lower-salinity waters, probably biologically-mediated reduction of Fe(III) to Fe(II) in the
56 Fe-rich ferrihydrite present in sediments, can release 56
Fe-rich Fe(II) to groundwater, that thus acquires the 56
Fe-rich signature. Lastly, as the Friulan Plain was significantly disseminated of Fe wastes from smelter plants in the past, the more positive d56Fe values measured in those groundwater samples were explained by waste leaching (Castorina et al., 2013). As Fe industrial pollution does not occur in the Ravenna Plain, where however, isotopic values nearing those positive of the Friulan Plain, have also been measured, this may render the above explanation not fully plausible, suggesting that the more positive d56Fe measured in the Friulan Plain can be due mainly to more extreme natural causes.
References
1. E. Pezzetta, A. Lutman, I. Martinuzzi, C. Viola, G. Bernardis and V. Fuccaro, Iron concentrations in selected groundwater samples from the lower Friulian Plain, northeast Italy: Importance of salinity. Environ. Earth Sci., 62, pp. 377–391, 2011.
2. F. Castorina, R. Petrini, A. Galic, F.F. Slejko, U. Aviani, E. Pezzetta and G. Cavazzini, The fate of iron in waters from a coastal environment impacted by metallurgical industry in northern Italy: Hydrochemistry and Fe-isotopes. Applied Geochemistry, 2013 (in press)
The role of brassinosteroids in controlling plant height in poaceae : a genetic perspective
No full textThe most consistent phenotype of the brassinosteroid (BR)-related mutants is the dwarf habit. This observation has been reported in every species in which BR action has been studied through a mutational approach. On this basis, a significant role has been attributed to BRs in promoting plant growth. In this review, we summarize the work conducted in rice, maize, and barley for the genetic dissection of the pathway and the functional analysis of the genes involved. Similarities and differences detected in these species for the BR role in plant development are presented. BR promotes plant cell elongation through a complex signalling cascade that modulates the activities of growth-related genes and through the interaction with gibberellins (GAs), another class of important growth-promoting hormones. Evidence of BR–GA cross-talk in controlling plant height has been collected, and mechanisms of interaction have been studied in detail in Arabidopsis thaliana and in rice (Oryza sativa). The complex picture emerging from the studies has highlighted points of interaction involving both metabolic and signalling pathways. Variations in plant stature influence plant performance in terms of stability and yield. The comprehension of BR’s functional mechanisms will therefore be fundamental for future applications in plant-breeding programs
Transition from mildly-tholeiitic to calc-alkaline suite: the case of Chichontepec volcanic centre, El Salvador, Central America
No full textThe Chichontepec volcano is a Plio-Pleistocene composite volcano that erupted lavas ranging from high-alumina basalts to dacites. It experienced a caldera-forming paroxysmal eruption during the early Pleistocene. Pre-caldera lavas are mildly tholeiitic and they evolved mainly by low pressure crystal fractionation, notwithstanding the fact that most mafic lavas (low-MgO high-alumina basalts) retain traces of polybaric evolution. Conversely, post-caldera lavas, which are mainly pyroxene andesites, are clearly calc-alkaline, having evolved by open-system crystal fractionation. Sr-Nd isotopic data and trace elements characteristics indicate that the same mantle source was involved in the petrogenesis of these series. Modelling the AFC process showed that it did not play any role in the petrogenesis of these rocks; a crystal fractionation model is considered to be more relevant. A slight variation in the fractionating assemblage could have caused the transition from an early mildly tholeiitic trend to a late calc-alkaline one. Mineralogical evidence, mass-balance calculations and elemental chemistry support this hypothesis, assuming that the greater amount of pyroxene on the liquidus is at the expense of plagioclase; this would have prevented the trend in iron enrichment. (C) 1998 Elsevier Science B.V. All rights reserved
FRATTURA COMPLICATA DI CORONA-RADICE: REINCOLLAGGIO DEI FRAMMENTI DEGLI INCISIVI PERMANENTI. PRESENTAZIONE DI UN CASO
No full textLE DISCREPANZE TRASVERSALI: METODICA TERAPEUTICA MEDIANTE DISGIUNTORE RAPIDOCON RIPOSIZIONAMENTO MANDOBOLARE
No full textEmanuele Castorina : I poetae novelli, contributo alla storia della cultura latina nel II secolo d. C. Firenze
No full textG. E. Emanuele Castorina : I poetae novelli, contributo alla storia della cultura latina nel II secolo d. C. Firenze. In: Bulletin de l'Association Guillaume Budé,n°10, juin 1950. p. 111
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