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Agency: Cordis | Branch: H2020 | Program: RIA | Phase: SC5-11d-2015 | Award Amount: 5.40M | Year: 2016

Five of the 20 raw materials identified by the European Commission as critical are commonly found in association with alkaline rocks and carbonatites (heavy and light rare earth elements, niobium, fluorspar, and phosphate). Other elements increasingly important for hi-tech applications, and found in these rocks include hafnium (Hf), tantalum (Ta), scandium (Sc) and zirconium (Zr). In fact, there is a greater chance of a carbonatite complex having resources economic to mine than any other rock type (about 20 active mines in ca. 500 known carbonatite complexes). Less than 3% of critical raw materials supply is indigenous to the EU. However, deposits are known and exploration is ongoing in parts of northern Europe. In central and southern Europe the presence of abundant alkaline volcanic rocks indicates the likelihood that deposits exist within about a km of the surface. This project will make a step-change in exploration models for alkaline and carbonatite provinces, using mineralogy, petrology, and geochemistry, and state-of-the-art interpretation of high resolution geophysics and downhole measurement tools, to make robust predictions about mineral prospectivity at depth. This will be achieved through studies at seven key natural laboratories, combined with Expert Council workshops. The results will be incorporated into new geomodels on multiple scales. In contrast to known deposits, Europe is well endowed with expertise. The project brings together industry partners involved in exploration, geophysics and environmental assessment with two geological surveys, a major museum and five universities. The results will make Europe the world leader in this specialist area. They will give the four SME industry partners world-leading expertise to develop and expand their businesses, transferring their business expertise from Africa to Europe. The project will help give European hi-tech industry the confidence to innovate in manufacturing using critical raw materials.

Cellini L.,University of Chieti Pescara
World Journal of Gastroenterology | Year: 2014

Helicobacter pylori (H. pylori) is widely adaptable for colonization in human stomachs in more than half of the world's population. The microorganism is characterized by an unusual capability of arranging itself in both genotypic and phenotypic ways. Stressing conditions, including antimicrobial agents in sub-inhibitory concentrations, facilitate entering the viable but nonculturable state in which bacterial cells acquire the coccoid form. This morphotype represents an important strategy for bacterial survival in unsuitable conditions and also allows escape from the immune system. H. pylori is capable of forming biofilm outside and inside the host. For the bacterial population, the sessile growth mode represents an ideal environment for gene rearrangement, as it allows the acquiring of important tools aimed to improve bacterial "fitness" and species preservation. Biofilm formation in H. pylori in the human host also leads to recalcitrance to antibiotic treatment, thus hampering eradication. These lifestyle changes of H. pylori allow for a "safe haven" for its survival and persistence according to different ecological niches, and strongly emphasize the need for careful H. pylori surveillance to improve management of the infection. © 2014 Baishideng Publishing Group Inc. All rights reserved. Source

Coletti C.,University of Chieti Pescara
Accounts of chemical research | Year: 2012

Transition metal complexes containing unsaturated carbenes have enjoyed a recent surge in research interest. In addition to showing potential as molecular wires and as components of opto-electronic materials, they provide multifaceted reactive sites for organic synthesis. In this Account, we describe results of recent theoretical studies that delineate the main features of electronic structure and bonding in allenylidenes and higher cumulenylidene complexes, [L(m)M]{box drawing double horizontal}C({box drawing double horizontal}C)(n){box drawing double horizontal}CR(1)R(2) (where L represents the ligand, M the metal, and n ≥ 1). Although free cumulenylidene ligands, :C({box drawing double horizontal}C)(n){box drawing double horizontal}CR(1)R(2), are extremely unstable and reactive species, they can be stabilized by coordination to a transition metal. The σ-donation of the electron lone pair on the terminal carbon atom to an empty metal d-orbital, together with the simultaneous π back-donation from filled metal d(π)-orbitals to empty cumulene π* system orbitals, leads to the formation of a strong M{box drawing double horizontal}C bond with multiple character. Density functional theory studies on the model systems [(CO)(5)Cr({box drawing double horizontal}C)(n)CH(2)] and [trans-Cl(PH(3))(4)Ru({box drawing double horizontal}C)(n)CH(2)](+) (where n = 1-9) have been useful in interpreting the structural and spectroscopic properties and the reactivity of this class of complexes. Geometry optimizations significantly contributed to the generalization of the sparse structural data available for allenylidene, butatrienylidene, and pentatetraenylidene complexes to higher cumulenylidene complexes (with up to eight carbon atoms in the chain), which show a clear structural trend. In particular, the geometries of all even-chain cumulenes are consistent with an almost purely cumulenic structure, whereas the geometries of odd-chain cumulenes present a significant polyyne-like carbon-carbon bond length alternation. The calculated bond dissociation energies (BDEs) of the cumulenylidene ligand remain almost constant on lengthening the cumulene chain. These BDEs indicate that there is no thermodynamic upper limit to the cumulene chain length and suggest that the synthetic difficulties in preparing higher cumulenylidenes are due to an increase in reactivity. The calculated charges on the carbon atoms show no significant polarization along the cumulene chain, indicating that charge distribution is not important in determining the regioselectivity of either electrophilic or nucleophilic attack, which is instead determined by frontier orbital factors. The breakdown of the contributions from the metal and the carbon atoms along the chain to the HOMO and LUMO shows that the HOMO has contributions mainly from the metal and the carbon atoms in even positions along the chain (C(2), C(4), C(6), and higher). In contrast, the LUMO has contributions mainly from the carbon atoms in odd positions along the chain (C(1), C(3), C(5), and higher), thus explaining the experimentally observed regioselectivity of electrophilic and nucleophilic attacks, which are directed, respectively, to even and odd positions of the cumulenylidene chain. The study of the electronic structure of cumulenylidenes has allowed us not only to give a consistent rationale for the main structural and spectroscopic properties and for the reactivity of this emerging class of compounds but also to predict the effect of ancillary ligands on the metal center or substituents on the carbon end. The result is a useful guide to new developments in the still-underexplored fields of this fascinating class of compounds. Source

Vazzana N.,University of Chieti Pescara
Journal of the American Heart Association | Year: 2013

Low high-density lipoprotein (HDL) levels are major predictors of cardiovascular (CV) events, even in patients on statin treatment with low-density lipoprotein (LDL) at target. In animal models HDLs protect LDL from oxidation and blunt platelet activation. Our study aimed to examine whether HDL levels are related to in vivo oxidative stress and platelet activation, as determinants of atherothrombosis. Urinary 8-iso-PGF2α and 11-dehydro-TXB2, in vivo markers of oxidative stress and platelet activation, respectively, were measured in 65 coronary heart disease (CHD) normocholesterolemic patients with HDL ≤35 mg/dL, and in 47 CHD patients with HDL >35 mg/dL. The 2 eicosanoids were also measured before and after an intensive exercise program in sedentary people (n=18) and before and after fenofibrate treatment in otherwise healthy subjects with low HDL (n=10). Patients with HDL ≤35 mg/dL showed significantly higher urinary 8-iso-PGF2α (median [25th to 75th percentiles]: 289 [189 to 380] versus 216 [171 to 321] pg/mg creatinine, P=0.019) and 11-dehydro-TXB2 (563 [421 to 767] versus 372 [249 to 465] pg/mg creatinine, P=0.0001) than patients with higher HDL. A direct correlation was found between urinary 8-iso-PGF2α and 11-dehydro-TXB2 in the entire group of patients (ρ=0.77, P<0.0001). HDL levels were inversely related to both 8-iso-PGF2α (ρ=-0.32, P=0.001) and 11-dehydro-TXB2 (ρ=-0.52, P<0.0001). On multiple regression, only 8-iso-PGF2α (β=0.68, P<0.0001) and HDL level (β=-0.29, P<0.0001) were associated with urinary 11-dehydro-TXB2 excretion, independent of sex, age, smoking, hypertension, diabetes, previous myocardial infarction, total cholesterol, LDL, and triglycerides. Both intensive exercise and fenofibrate treatment significantly reduced the 2 eicosanoids in healthy subjects, in parallel with an HDL increase. A low HDL phenotype, both in CHD patients and in healthy subjects, is associated with increased lipid peroxidation and platelet activation. These data provide novel insight into the mechanisms linking low HDL with increased CV risk. Source

Mari C.,University of Chieti Pescara
Applied Energy | Year: 2014

The analysis presented in this paper aims to put in some evidence the role of nuclear power as hedging asset against the volatility of electricity prices. The unpredictability of natural gas and coal market prices as well as the uncertainty in environmental policies may affect power generating costs, thus enhancing volatility in electricity market prices. The nuclear option, allowing to generate electricity without carbon emissions, offers the possibility to reduce the volatility of electricity prices through optimal diversification of power generating technologies. This paper provides a methodological scheme to plan well diversified "portfolios" of generating capacity that minimize the electricity price risk induced by random movements of fossil fuels market prices and by unpredictable fluctuations of carbon credits prices. The analysis is developed within a stochastic environment in which the dynamics of fuel prices as well as the dynamics of carbon credits prices is assumed to evolve in time according to well defined Brownian processes. Starting from market data and using Monte Carlo techniques to simulate generating cost values, the hedging argument is developed by selecting optimal portfolio of power generating technologies using a mean-variance approach. © 2013 Elsevier Ltd. Source

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