1,247 research outputs found

    La prima rivelazione diretta delle onde gravitazionali: una nuova finestra sull’Universo

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    The first direct observation of gravitational waves using the interferometer detectors of the LIGO-Virgo collaboration has marked the start of gravitational astronomy. The extreme difficulty of such measurements called for many years of hard work, but finally, on 14 September 2015, the signal produced by the coalescence of two black holes of large mass was observed.La prima osservazione diretta delle onde gravitazionali con i rivelatori interferometrici della collaborazione LIGO-Virgo ha dato inizio all’astronomia gravitazionale. La grande difficoltà della misura ha richiesto molti anni di lavoro, ma finalmente il 14 settembre 2015 è stato osservato il segnale proveniente dalla coalescenza di due buchi neri di grande massa

    Un agosto pieno di sorprese gravitazionali

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    L’interferometro per la rivelazione di onde gravitazionali Advanced Virgo è entrato in funzione il 1 agosto 2017. I 25 giorni di presa dati con tre interferometri hanno segnato la nascita dell’astronomia multimessaggera. Dapprima è stata rivelata la coalescenza di due buchi neri, ricostruendo per la prima volta la posizione della sorgente. Poco dopo si è scoperta la coalescenza di un sistema binario di stelle di neutroni, osservata contemporaneamente per la prima volta anche nell’emissione elettromagnetica.The gravitational wave interferometric detector Advanced Virgo began its data collecting on August 1, 2017. The following 25 days saw the dawn of multimessenger astronomy. First, a two black hole merger was detected, with the first reconstruction of the source position in the sky. A few days later, a binary neutron star system merger was discovered and for the first time observed simultaneously even through electromagnetic emission

    Geology of the ‘Coltre della Val Marecchia’ (Romagna-Marche Northern Apennines, Italy)

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    A detailed geological map at 1:50,000 scale of the Marecchia Valley and adjoining areas (Northern Apennines, NA, Italy) is presented here. The Marecchia Valley represents a geological ‘unicum’ for the NA and it has been the focus of scientific debate for a long time, due to the occurrence in the area of the ‘Coltre della Val Marecchia (CVM)’, a complex stack of allochthonous and semi-allochthonous units emplaced in a foredeep basin during the Late Miocene to Early Pliocene. In order to clarify the geological evolution for this area, the lithostratigraphic relationships and the tectonic framework have been studied, allowing better understanding of the complex relationships between tectonics and sedimentation. The main result has been a new evolutionary framework for this sector of the orogen during the Late Miocene-Early Pliocene. Several new findings about the geological-structural setting and stratigraphy, result from the geological map presented here. These are overall supported by stratigraphic and tectonic evidence, which suggest time and modes of the CVM allochthonous emplacement within the Messinian-early Pliocene foredeep successions. Relationships between the allochthonous and autochthonous formations allowed recognition of two different bodies in the CVM, gravitationally emplaced following different trajectories and timing

    Physico-Chemical Traits of Raw and Cooked Fillets of Rainbow Trout (Oncorhynchus Mykiss) from Different Strains and Farms

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    Fillets and cooking yields, water holding capacity, textural properties, colour, proximate composition, collagen and fatty acids of five strains (IT1, IT2, IT3, USA, UK) of rainbow trout, Oncorhynchus mykiss, reared in three farms (F1, F2, F3), were measured before and after cooking. Physico-chemical parameters of the strains greatly differed both in raw and cooked state. IT2 and USA recorded the highest yields. IT2 distinguished from the other strains, showing lowest values of hardness, chewiness, gumminess and springiness. It also had brighter and less pigmented flesh with low fat, mainly in the raw state. USA strain showed the most valuable traits in terms of texture and colour, and had higher fat and collagen content in flesh. The physico-chemical profile of each strain was differently modified by cooking. USA strain maintained a positive texture and colour profile after cooking and its quality was the best

    Microencapsulation of semisolid ketoprofen/polymer microspheres

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    Ketoprofen controlled release microspheres were prepared, by emulsion/solvent evaporation, at 15 degreesC, in order to avoid the formation of semisolid particles. An identical procedure was carried out at 60 degreesC to speed up the solvent evaporation and the formed semisolid microspheres were directly microencapsulated by complex coacervation and spray-dried in order to recover them as free flowing powder. Microspheres and microcapsules were characterized by scanning electron microscopy, differential scanning calorimetry, X-ray diffractometry, in vitro dissolution studies, and then used for the preparation of tablets. During this step, the compressibility of the prepared powders was measured. Microspheres and microcapsules showed compaction abilities by far better than those of the corresponding physical mixtures. In fact, it was impossible to obtain tablets by direct compressing drug and polymer physical mixtures, but microspheres and microcapsules were easily transformed into tablets. Finally, in vitro dissolution studies were performed and the release control of the tablets was pointed out. Microspheres were able to control ketoprofen release only after their transformation into tablets. Tablets containing eudragit RS were the most effective in slowing down drug release

    Absorption and scattering properties of carbon nanohorn-based nanofluids for direct sunlight absorbers

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    In the present work, we investigated the scattering and spectrally resolved absorption properties of nanofluids consisting in aqueous and glycol suspensions of single-wall carbon nanohorns. The characteristics of these nanofluids were evaluated in view of their use as sunlight absorber fluids in a solar device. The observed nanoparticle-induced differences in optical properties appeared promising, leading to a considerably higher sunlight absorption with respect to the pure base fluids. Scattered light was found to be not more than about 5% with respect to the total attenuation of light. Both these effects, together with the possible chemical functionalization of carbon nanohorns, make this new kind of nanofluids very interesting for increasing the overall efficiency of the sunlight exploiting device

    Tumor Suppressor Role of hsa-miR-193a-3p and -5p in Cutaneous Melanoma

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    Background: Remarkable deregulation of several microRNAs (miRNAs) is demonstrated in cutaneous melanoma. hsa-miR-193a-3p is reported to be under-expressed in tissues and in plasma of melanoma patients, but the role of both miR-193a arms in melanoma is not known yet. Methods: After observing the reduced levels of miR-193a arms in plasma exosomes of melanoma patients, the effects of hsa-miR-193a-3p and –5p transfection in cutaneous melanoma cell lines are investigated. Results: In melanoma cell lines A375, 501Mel, and MeWo, the ectopic over-expression of miR-193a arms significantly reduced cell viability as well as the expression of genes involved in proliferation (ERBB2, KRAS, PIK3R3, and MTOR) and apoptosis (MCL1 and NUSAP1). These functional features were accompanied by a significant downregulation of Akt and Erk pathways and a strong increase in the apoptotic process. Since in silico databases revealed TROY, an orphan member of the tumor necrosis receptor family, as a potential direct target of miR-193a-5p, this possibility was investigated using the luciferase assay and excluded by our results. Conclusions: Our results underline a relevant role of miR-193a, both -3p and -5p, as tumor suppressors clarifying the intracellular mechanisms involved and suggesting that their ectopic over-expression could represent a novel treatment for cutaneous melanoma patients

    Strontium substituted hydroxyapatite with β-lactam integrin agonists to enhance mesenchymal cells adhesion and to promote bone regeneration

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    Multi-functionalization of calcium phosphates to get delivery systems of therapeutic agents is gaining increasing relevance for the development of functional biomaterials aimed to solve problems related to disorders of the muscolo-skeletal system. In this regard, we functionalized Strontium substituted hydroxyapatite (SrHA) with some β-lactam integrin agonists to develop materials with enhanced properties in promoting cell adhesion and activation of intracellular signaling as well as in counteracting abnormal bone resorption. For this purpose, we selected two monocyclic β-lactams on the basis of their activities towards specific integrins on promoting cell adhesion and signalling. The amount of β-lactams loaded on SrHA could be modulated on changing the polarity of the loading solution, from 3.5–24 wt% for compound 1 and from 3.2–8.4 wt% for compound 2. Studies on the release of the β-lactams from the functionalized SrHA in aqueous medium showed an initial burst followed by a steady-release that ensures a small but constant amount of the compounds over time. The new composites were fully characterized. Co-culture of human primary mesenchymal stem cells (hMSC) and human primary osteoclast (OC) demonstrated that the presence of β-lactams on SrHA favors hMSC adhesion and viability, as well as differentiation towards osteoblastic lineage. Moreover, the β-lactams were found to enhance the inhibitory role of Strontium on osteoclast viability and differentiation
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