395 research outputs found

    Chemical-physical and ecological characterisation in the environmental project of a polluted coastal area: the Bagnoli case study

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    The Bagnoli Bay (southern Tyrrhenian Sea, Naples, Italy) has been impacted for about one century by heavy anthropogenic pollution due to an important steel plant. A multidisciplinary environmental research, aimed at the reclamation of the marine contaminated area, was planned in order to evaluate, through quantitative data, the chemical-physical and ecological characteristics of marine sediments; the latter ones are strictly related to the composition and structure of benthic foraminiferal assemblages. A comprehensive statistical approach, considering all data, was attempted in order to single out the influence of pollutants on the single species distribution. The results show strong heavy metal pollution (Fe, Mn, Pb and Zn) in the vicinity of the industrial plant. Many foraminiferal species (Haynesina germanica, Miliolinella subrotunda,Quinqueloculina parvula), have a good tolerance to some trace metals while, Bulimina sublimbata, Elphidiummacellum and Miliolinella dilatata show a good tolerance to PAHs pollution

    Physical and Aerodynamic Characterization of Particle Clusters at Sakurajima Volcano (Japan)

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    The process of particle aggregation significantly affects ash settling dynamics associated with volcanic explosive eruptions. Several experiments have been carried out to investigate the physics of ash aggregation and dedicated numerical schemes have been developed to produce more accurate forecasting of ash dispersal and sedimentation. However, numerical description of particle aggregation is complicated by the lack of complete datasets on natural samples required for model validation and calibration. Here we present a first comprehensive dataset for the internal structure, aerodynamical properties (e.g., size, density, terminal velocity) and grain size of constituting particles of a variety of aggregate types collected in the natural laboratory of Sakurajima Volcano (Japan). Even though the described particle clusters represent the most common types of aggregates associated with ash-rich fallouts, they are of difficult characterization due to the very low potential of preservation in tephra-fallout deposits. Properties were, therefore, derived based on a combination of high-resolution-high-speed videos of tephra fallout, scanning electron microscope analysis of aggregates collected on adhesive paper and analysis of tephra samples collected in dedicated trays. Three main types of particle clusters were recognized and quantitively characterized: cored clusters (PC3), coated particles (PC2), and ash clusters (PC1) (in order of abundance). A wide range of terminal velocities (0.5–4 m/s) has been observed for these aggregates, with most values varying between 1 and 2 m/s, while aggregate size varies between 200 and 1,200 Âµm. PC1, PC2, and PC3 have densities between 250 and 500, 1,500 and 2,000, and 500 and 1,500 kg/m3, respectively. The size of the aggregate core, where present, varies between 200 and 750 Âµm and increases with aggregate size. Grain size of tephra samples was deconvoluted into a fine and a coarse Gaussian subpopulation, well correlated with the grain size of shells and of the internal cores of aggregates, respectively. This aspect, together with the revealed abundance of PC3 aggregates, reconciles the presence of a large amount of fine ash (aggregate shells) with coarse ash (aggregate cores) and better explains the grain size distribution bimodality, the high settling velocity with respect to typical PC1 velocities and the low settling velocities of large aggregates with respect to typical PC2 velocity. Furthermore, ash forming the aggregates was shown to be always finer than 45 Âµm, confirming the key role played by aggregation processes in fine ash deposition at Sakurajima

    Anthropic pressures on Nature 2000 Sites: recommendations and monitoring criteria for the pollution emergency response activities within the Orbetello lagoon

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    L’elevato valore naturalistico e socioeconomico di un Sito Natura 2000 richiede che tutte le attività antropiche che si svolgono al suo interno (es. pesca, turismo, trasporti, attività industriali, etc.) siano gestite in maniera tale da non pregiudicare le specie e gli habitat per i quali l’area è stata designata. Molti di questi Siti sono ambienti di transizione, ovvero zone che costituiscono il passaggio naturale tra terra e mare. La loro posizione di interfaccia tra questi due ambienti li rende ecosistemi unici e biologicamente molto produttivi, sede di meccanismi di regolazione dei processi interattivi della biosfera nelle due fasi, terrestre e marina. In alcuni Siti la presenza di attività antropiche diffuse e prolungate nel tempo ha portato al riscontro di stati di contaminazione elevata, fino all’inclusione di queste zone, o parti di esse, tra i Siti di bonifica di Interesse Nazionale (SIN). Il presente lavoro descrive le linee di indirizzo e le attività di monitoraggio da attuare per la salvaguardia della salute pubblica e dell’ambiente nel corso degli interventi di messa in sicurezza di emergenza predisposti nell’area lagunare antistante l’area industriale Ex Sitoco, all’interno della perimetrazione del SIN di Orbetello, incluso in un Sito di Importanza Comunitaria. Le matrici ambientali potenzialmente a rischio a causa dell’esecuzione di tali interventi sono: acqua, sedimento, biocenosi acquatiche, avifauna, uomo. È altresì importante valutare gli effetti che le ipotetiche modifiche su microscala, apportate a livello di ogni matrice, potrebbero causare nel lungo periodo su macroscala.The high naturalistic and socio-economic value of Natura 2000 sites requires that all human activities performed within their borders (e.g. fishing, tourism, transports, industrial activities) are regulated. Indeed, the site management should assure the effective safeguard of all species and habitats of European interest included in the protected area. A lot of such sites are located in transitional environments, that are areas characterised by a natural progression from the terrestrial to the water environments. Such environments include unique and very productive habitats, and they represent the regulation mechanisms of the interactive processes of the terrestrial and marine biosphere. In some sites, the presence of human activities that are distributed both in space and time has led to high levels of contamination, that in some cases even required their inclusion in Reclamation Sites of National Interest (SIN). The present study describes the planning and monitoring activities to be performed in order to safeguard human and environment health during the actions of MISE in the lagoonal area in front of the industrial area Ex Sitoco, within the borders of the Orbetello SIN, included in a SCI. The environmental parameters that are potentially at risk due to such activities are: water, sediment, water biocenosis, birds, humans. Furthermore, it is important to evaluate the effects that potential variations at the microscale level may cause at the macroscale level

    Assessing the potential of INFFER to improve management of agro-environmental assets in Tuscany

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    In the European Union, as in many parts of the world, there is increasing pressure to demonstrate that environmental projects achieve expected outcomes and are cost-effective. This paper reports on a trial application of an environmental investment framework, the Investment Framework for Environmental Resource (INFFER). The framework, based on benefit:cost analysis principles, was applied to agro-environmental assets in the Mugello and Valdisieve areas of northern Tuscany, Italy. Farmers, environmental and institutional representatives and technical experts took part in the process of identifying agro-environmental assets in the region. A total of 26 assets were identified, and of these, only 2 (the last remaining population of Cistus laurfolius within the natural protected area of local interest ( Area Naturale Protetta di Interesse Locale , ANPIL) of Santa Brigida, and the Sant' Antonio forest were selected as having reasonable prospects of progressing to cost-effective projects (benefit:cost ratio>1). Detailed projects were developed for both assets and found to be cost-effective based on available information. While the mindset of being clear about identifying and valuing natural assets was a new concept to participants, overall the process worked well. The factors considered in calculating a benefit:cost ratio, including technical feasibility, adoption and compliance factors, socio-political risks, costs and the likelihood of obtaining long-term funding to maintain project benefits, were all relevant in Tuscany and required the knowledge of local experts. Overall, INFFER appears relevant and useful in an EU context, and, in particular, is highly compatible with the EU Natura 2000 nature and biodiversity policy

    From 3,4-dinitrothiophene to nitrocyclopropanes and 1,1'-dinitro-1,1'-bi(cyclopropyl) compounds

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    Treatment of (E,E)-1,4-diaryl-2,3-dinitro-1,3-butadienes (I) with diazomethane in Et2O or THF represents a facile and high-yielding route to 2,2'-diaryl-1,1'-dinitro-1,1'-bi(cyclopropyl)s. The process exclusively produces diastereomeric mixts. of a chiral d,l pair and a meso form, the relative percentages of which depend on the aryl moiety, consistently with a concerted syn-stereoselective cyclopropanation of each double bond. With 1 mol-equiv of CH2N2, the cyclopropanation can effectively be limited to one double bond of the starting dinitrobutadiene, thus allowing a synthetically useful differentiation between the two originally conjugated nitrovinyl moieties. As verified with model derivs., the resulting vinylcyclopropanes can be cyclopropanated with excess diazomethane to give the same diastereomeric mixts. as obtained by direct bis(cyclopropanation) of I

    Low-Energy Fragmentation Dynamics at Copahue Volcano (Argentina) as Revealed by an Infrasonic Array and Ash Characteristics

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    Ash-rich eruptions represent a serious risk to the population living nearby as well as at thousands of kilometers from a volcano. Volcanic ash is the result of extensive magma fragmentation during an eruption, and it depends upon a combination of magma properties such as rheology, vesicularity and permeability, gas overpressure and the possible involvement of external fluids during magma ascent. The explosive process generates infrasonic waves which are directly linked to the outflow of the gas-particle mixture in the atmosphere. The higher the overpressure in the magma, the higher should be the exit velocity of the ejected material and the acoustic pressure related to this process. During violent eruptions, fragmentation becomes more efficient and is responsible for the extensive production of ash which is dispersed in the atmosphere. We show that the phase of intense ash emission that occurred during March 2016 at Copahue volcano (Argentina) generated a very low (0.1 Pa) infrasonic amplitude at 13 km, raising a number of questions concerning the links among acoustic pressure, gas overpressure and efficiency of magma fragmentation. Infrasound and direct observations of the eruptive plume indicate that the large quantity of ash erupted at Copahue was ejected with a low exit velocity. Thus, it was associated with eruptive dynamics driven by a low magma overpressure. This is more evident when infrasonic activity at Copahue is compared to the moderate explosive activity of Villarrica (Chile), recorded by the same array, at a distance of 193 km. Our data suggest a process of rigid fragmentation under a low magma overpressure which was nearly completely dissipated during the passage of the erupting mixture through the granular, ash-bearing crater infilling. We conclude that ash released into the atmosphere during low-energy fragmentation dynamics can be difficult to monitor, with direct consequences for the assessment of the related hazard and management of eruptive crises.Fil: Hantusch, Marcia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; ArgentinaFil: Lacanna, Giorgio. Università degli Studi di Firenze; ItaliaFil: Ripepe, Maurizio. Università degli Studi di Firenze; ItaliaFil: Montenegro, Verónica Matilde. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; ArgentinaFil: Valderrama, Oscar. Servicio Nacional de Geologia y Mineria (SERNAGEOMIN); ChileFil: Farias, Camila Belen. Ministerio de Defensa. Secretaria de Planeamiento. Servicio Meteorológico Nacional; ArgentinaFil: Caselli, Alberto Tomás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; ArgentinaFil: Gabellini, Pietro. Università degli Studi di Firenze; ItaliaFil: Cioni, Raffaello. Università degli Studi di Firenze; Itali

    FSHD muscular dystrophy Region Gene 1 binds Suv4-20h1 histone methyltransferase and impairs myogenesis

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    Facioscapulohumeral Muscular Dystrophy (FSHD) is an autosomal dominant myopathy with a strong epigenetic component. It is associated with deletion of a macrosatellite repeat leading to over-expression of the nearby genes. Among them, we focused on FSHD Region Gene 1 (FRG1) since its over-expression in mice, X. laevis and C. elegans leads to muscular dystrophy-like defects, suggesting that FRG1 plays a relevant role in muscle biology. Here we show that, when overexpressed, FRG1 binds and interferes with the activity of the histone methyltransferase Suv4-20h1 both in mammals and Drosophila. Accordingly, FRG1 over-expression or Suv4-20h1 knockdown inhibits myogenesis. Moreover, Suv4-20h KO mice develop muscular dystrophy signs. Finally, we identify the FRG1/Suv4-20h1 target Eid3 as a novel myogenic inhibitor that contributes to the muscle differentiation defects. Our study suggests a novel role of FRG1 as epigenetic regulator of muscle differentiation and indicates that Suv4-20h1 has a gene-specific function in myogenesis

    New Histamine-Related Five-Membered N-Heterocycle Derivatives as Carbonic Anhydrase I Activators

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    A series of histamine (HST)-related compounds were synthesized and tested for their activating properties on five physiologically relevant human Carbonic Anhydrase (hCA) isoforms (I, II, Va, VII and XIII). The imidazole ring of HST was replaced with different 5-membered heterocycles and the length of the aliphatic chain was varied. For the most interesting compounds some modifications on the terminal amino group were also performed. The most sensitive isoform to activation was hCA I (K(A) values in the low micromolar range), but surprisingly none of the new compounds displayed activity on hCA II. Some derivatives (1, 3a and 22) displayed an interesting selectivity for activating hCA I over hCA II, Va, VII and XIII

    Towards flavour diffusion coefficient and electrical conductivity without ultraviolet contamination

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    By subtracting from a recent lattice measurement of the thermal vector-current correlator the known 5-loop vacuum contribution, we demonstrate that the remainder is small and shows no visible short-distance divergence. It can therefore in principle be subjected to model-independent analytic continuation. Testing a particular implementation, we obtain estimates for the flavour-diffusion coefficient (2 pi T D \gsim 0.8) and electrical conductivity which are significantly smaller than previous results. Although systematic errors remain beyond control at present, some aspects of our approach could be of a wider applicability.Comment: 7 pages. v2: clarifications added, published versio
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