191 research outputs found
Sedimentological and morpho-evolution maps of the 'Bosco Pantano di Policoro' coastal system (Gulf of Taranto, southern Italy)
This paper presents the results of a sedimentological study performed to characterize the ‘Bosco Pantano di Policoro e Costa Ionica Foce Sinni’ coastal system, in Basilicata (southern Italy), as part of the PROVIDUNE LIFE Project. The study was focused on the morpho-sedimentological characterization of both the emerged and submerged sectors of the beach system developed along a 3.5 km-long segment of the Ionian coast. A multitemporal comparison of historical aerial photos of the studied coastline concerning the last 100 years was executed. A geomorphological survey was carried out along 36 topographic profiles (each up to 200-m long); these were coupled with bathymetric profiles, reaching a depth of 213 m. Both topographic and bathymetric profiles were measured on three occasions (July, October, December 2010). Textural and compositional analyses of sediments were also performed. The results of this study were synthesized in a series of maps illustrating a schematic geological outline of the study area, a reconstruction of the Sinni river course and shoreline changes from 1908 to 2010 (1:2,400 scale), significant topographic (1:1,300 scale) and bathymetric (1:5,000 scale) profiles, three bathymetric charts (1:31,000 scale) and morpho-sedimentological features of both the coastal and nearshore sectors (1:15,000 scale).
This study provides a geological background that is crucial for any intervention planning, as well as for any coastal zone management projects. The results should be also used in order to protect coastal habitats, which is the ultimate goal of the LIFE project
Plio-Pleistocene stratigraphic and tectonic evolution of the foreland-foredeep-chain system in Southern Italy
Tidal signatures in Neogene to Quaternary mixed deposits of southern Italy straits and bays
Some of the Neogene to Quaternary sedimentary successions cropping out in the southern Italy orogenic belt exhibit distinct stratigraphic intervals of mixed, silici-bioclastic arenites. These deposits represent bay- and strait-fill successions that accumulated during tectonically-driven, rapid transgressions in peripheral marine basins of the central Mediterranean, experiencing microtidal conditions similar to those presently existing in the Mediterranean Sea.
The Upper Miocene to Middle Pleistocene successions of Basilicata, Calabria and NE Sicily, show laterallyaccreted, cross-strata of mixed composition, with the siliciclastic fraction derived from either sedimentary or metamorphic rocks and the bioclastic fraction produced by an in situ or near situ heterozoan factory. Tidal cyclicity of semi-diurnal and diurnal to monthly and yearly periodicities has been detected in the studied deposits, where tidal bundling is revealed by the rhythmic alternation of siliciclastic and bioclastic set of laminae, repeated according to different cycles. This rhythmic signature appears to be more evident where randomly-occurring processes, such as waves, storms and currents, were mitigated by engulfed or strait palaeo-settings.
Palaeo-bays preserved short-term tidal cycles in shoreface to offshore-transition mixed deposits because hydrodynamically isolated from open marine conditions and therefore subjected to tidal influence only during fair-weather periods. On the contrary, palaeo-straits recorded tidal cyclicities of longer duration in deeper mixed deposits subjected to steady tidal currents
Il nuovo Foglio Geologico 438 “Bari” in scala 1:50.000. Un importante contributo per la conoscenza geologica dell’area metropolitana di Bari
I risultati del rilevamento geologico del Foglio 438 “Bari” in scala 1:50.000 effettuato nell’ambito del progetto CARG (Cartografia Geologica) mostrano numerose differenze rispetto a quanto riportato nella Cartografia Ufficiale in scala 1:100.000, che rappresenta tuttora la cartografia di riferimento. Le differenze rilevate, o comunque le ulteriori informazioni ottenute dai nuovi studi, sono risultate molto significative soprattutto in corrispondenza dell’area metropolitana di Bari recentemente soggette ad intensa urbanizzazione ed espansione. Tenuto conto dei tempi necessari per poter divulgare tali dati, si è ritenuto importante, in occasione del Convegno sulla “Geologia urbana di Bari ed area metropolitana”, presentare una carta in scala 1:25.000 del territorio metropolitano barese, dove emergessero tutte le novità dei nuovi rilevamenti, al fine di poter fornire uno strumento utile a tutte le figure che operano sul territorio quotidianamente e che necessitano avere dati aggiornati
Amino acid transport in thermophiles: characterization of an arginine-binding protein in Thermotoga maritima
Members of the periplasmic binding protein superfamily are involved in the selective passage of ligands through bacterial cell membranes. The hyperthermophilic eubacterium Thermotoga maritima was found to encode a highly stable and specific periplasmic arginine-binding protein (TM0593). Following signal sequence removal and overexpression in Escherichia coli, TM0593 was purified by thermoprecipitation and affinity chromatography. The ultra-stable protein with a monomeric molecular weight of 27.7 kDa was found to exist as both a homodimer and homotrimer at appreciable concentrations even under strongly denaturing conditions, with an estimated transition temperature of 116 °C. Its multimeric structure may provide further evidence of the importance of quaternary structure in the movement of nutrients across bacterial membranes. Purified and refolded TM0593 was further characterized by fluorescence spectroscopy, mass spectrometry, and circular dichroism to demonstrate the specificity of the protein for arginine and to elucidate structural changes associated with arginine binding. The protein binds arginine with a dissociation constant of 20 mM as determined by surface plasmon resonance measurements. Due to its high thermodynamic stability, TM0593 may serve as a scaffold for the creation of a robust fluorescent biosensor
Depositi carbonatici infrapleistocenici di tipo foramol in sistemi di scarpata (Salento – Italia meridionale)
Along the eastern Salento coast (Southern Italy), Cretaceous to Quaternary carbonates crop out on a 100 m high escarpment that connects a wide and relatively flat area to the Otranto Strait (Ionian Sea). Along the escarpment, faulted and tilted Cretaceous and Eocene limestones record deposition in shallow-marine and marginal carbonate environments. Younger carbonates disconformably overlie this substratum and they formed when the region was partially submerged. Accordingly, Priabonian to Messinian carbonates which crop out along the escarpment were interpreted as slope deposits linked to reef systems developed on the margin of the top area, while lower Pleistocene carbonates cropping out at the base of the same escarpment were considered coastal in origin and formed during the uplift of the region. Stratigraphic and sedimentologic studies carried out on these lower Pleistocene carbonates demonstrate that also these deposits should be considered as slope deposits. The studied carbonates are foramol-type ones and discontinuously crop out along the lower part of the escarpment. They show a variable thickness (from a few meters up to several tens) and often exhibit a fan morphology; they correspond to small isolated bodies (up to a few km2 wide) developed in some indentations of the escarpment, and are composed of coarse skeletal grains mainly deposited via slumpings or grain flows. Successions are characterized by long clinobeds cut by slump scars downward passing to gullies; backsets, slumps and chaotic deposits fill these erosional features. Clinobeds are alternatively made up of molechfor and rodhalgal facies which respectively record resedimentation by grain flows of shallow marine carbonates developed on top of the region and along-slope carbonate production. Depositional systems correspond to small shallow-marine aprons whose discontinuous distribution along the escarpment (inside indentations) should be considered an original feature. The idea that these deposits record the Sicilian sea-level along the escarpment should be abandoned as they are not coastal deposits. The studied deposits should be correlated to the Calcarenite di Gravina Formation which in other areas of the Apulian Foreland (which the Salento region belongs to) are considered as the deposits linked to the subsidence induced by the estward migration of the south- Apennines orogenic system. The Quaternary uplift of the Salento region should be begun after the deposition of the studied slope deposits, as indicated also by a series of middle-upper Pleistocene marine terraces which start at heights higher than those ones of the studied deposits
From traumatic childhood to cocaine abuse: the critical function of the immune system
Background: Experiencing traumatic childhood is a risk factor for developing substance use disorder (SUD), but the mechanisms that underlie this relationship have not been determined. Adverse childhood experiences affect the immune system and the immune system mediates the effects of psychostimulants. However, whether this system is involved in the etiology of SUD in individuals who have experience early life stress is unknown. Methods:In this study, we performed a series of ex vivo and in vivo experiments in mice and humans to define the function of the immune system in the early-life stress-induced susceptibility to the neurobehavioral effects of cocaine. Results: We provide evidence that exposure to social-stress (S-S) at an early age permanently sensitizes the peripheral (splenocytes) and brain (microglia) immune responses to cocaine in mice. In the brain, microglial activation in the ventral tegmental area (VTA) of S-S mice was associated with functional alterations in dopaminergic neurotransmission, as measured by whole-cell voltage clamp recordings in dopamine (DA) neurons. Notably, preventing immune activation during the S-S exposure reverted the effects of DA in the VTA and the cocaine-induced behavioral phenotype to control levels. In humans, cocaine modulated Toll-like receptor 4-mediated innate immunity, an effect that was enhanced in cocaine addicts who had experienced a difficult childhood. Conclusions Collectively, our findings demonstrate that sensitization to cocaine in early-life-stressed individuals involves brain and peripheral immune responses and that this mechanism is shared between mice and humans
Amino acid transport in thermophiles: characterization of an arginine-binding protein in Thermotoga maritima. 2. Molecular organization and structural stability
ABC transport systems provide selective passage of metabolites across cell membranes and typically require the presence of a soluble binding protein with high specificity to a specific ligand. In addition to their primary role in nutrient gathering, the binding proteins associated with bacterial transport systems have been studied for their potential to serve as design scaffolds for the development of fluorescent protein biosensors. In this work, we used Fourier transform infrared spectroscopy and molecular dynamics simulations to investigate the physicochemical properties of a hyperthermophilic binding protein from Thermotoga maritima. We demonstrated preferential binding for the polar amino acid arginine and experimentally monitored the significant stabilization achieved upon binding of ligand to protein. The effect of temperature, pH, and detergent was also studied to provide a more complete picture of the protein dynamics. A protein structure model was obtained and molecular dynamic experiments were performed to investigate and couple the spectroscope observations with specific secondary structural elements. The data determined the presence of a buried ẞ-sheet providing significant stability to the protein under all conditions investigated. The specific amino acid residues responsible for arginine binding were also identified. Our data on dynamics and stability will contribute to our understanding bacterial binding protein family members and their potential biotechnological applications
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