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Over the last years, several regulations have been used to rule the dynamics of the transport of dangerous substances. As a consequence, a number of regulations concerning the international railway transport of dangerous goods impacted on rail transport, Regulation 1907/2006 and Regulation 1272/2008, increased toxicological information assets and tools that can be addressed in the event of a health emergency. The purpose of this study is to analyze dispersion scenarios to describe the consequences of an intentional release of propane, butane, or chlorine. Every scenario is designed to outline a hypothetical terrorist attack in a railway station where the compounds are released in the form of aerosol, boiling liquid expanding vapor explosion, or explosion. The toxicological exposure dynamics were modeled by means of tools such as the ALOHA software (Environmental Protection Agency). The simulations show different dispersions for all considered chemicals: chlorine covers a larger area, liquid butane is the most persistent and much hazardous for inflammability and toxicity, and propane shows destructive shock wave power and relative acute outdoor toxicity. The exposure rates were eventually estimated using the “Green Book” parameters (Netherlands Organization for Applied Scientific Research).

Here, we report the genome sequence of a rare bivalent strain of Clostridium botulinum , A2B3 87. The strain was isolated from a foodborne botulism case that occurred in Italy in 1995. The case was characterized by rapid evolution of the illness and failure of conventional treatments.

The novel β-diketo compound (3-acetyl-4-oxopentanoic acid) OPAA is here synthesized and completely characterized in the solid state by means of X-ray crystallography and in solution by potentiometry and 1H and 13C NMR spectroscopy. In the solid state, OPAA exhibits the di-keto (DK) structure, however, in solution, we can observe a strong solvent dependent tautomeric equilibrium. Theoretical ab initio calculations employing DFT at the B3LYP/6-311G** level, and different methods of theoretical model chemistry (CBS-4M, G3MP2, CBS-QB3) are used to extensively investigate the tautomeric equilibrium and compare it with experimental data. Solvent effects are evaluated using a CPCM continuum solvation method; among all applied methods, CBS-4M is the one that better predicts experimental data and is able to qualitatively describe tautomeric equilibrium in solution, allowing thermodynamic calculations of pKa. Furthermore a supermolecular solvent approach is used to better analyze solvent–solute interactions in order to predict chemical properties.

During the last few decades, the oxygenated chelant complexes of the Gallium(III) ion have been utilised in biological and pharmaceutical fields, because of their remarkable therapeutical properties, especially for the clinical anti-cancer treatments. Main purpose of the present work is to investigate, from a theoretical and computational point of view, the thermodynamic, structural and electronic properties of the complexes and the complexation equilibria of the Ga(III) ion with two oxygenated chelant ligands (acetylacetone and 1,7-diphenyl-5-hydroxy-1,4,6-heptatrien-3-one), in vacuo. Comparisons with Literature experimental data are even discussed. (C) 2011 Elsevier B.V. All rights reserved.

In the present study, we investigate the structures of glucosylated curcumin derivatives with DFT at B3LYP/6-31G* level. A conformational analysis is performed in order to determine the conformational minimum (GS) and rotational transition state (TS) of curcumin derivatives and then their electronic features are evaluated. HOMO and LUMO frontier orbitals and maps of electron density potential (MEPs) are plotted and compared. In order to correlate their predicted spectroscopic properties with IR, UV–vis and NMR experimental data we extended the theoretical study on electronic properties to different solvents (H2O, MeOH, ACN, DMSO). The main finding is that the curcuminic core maintains the same geometrical and electronic structures in all compounds miming the metal coordination capability showed by curcumin. Therefore, we may confirm that the presence of glucose does not affect the electronic properties of the derivatives. Copyright © 2010 John Wiley & Sons, Ltd.

Turmeric extracts, among which curcumin and bis-demethoxycurcumin, are by far known for their therapeutic activities. In this study we propose easy and low cost synthetic pathways in order to obtain glucosyl-curcuminoids, safe and water soluble potential drugs and dyes, which may be implied in different fields ranging from pharmacology to food chemistry. The complete (1)H and (13)C NMR characterization of naturally occurring curcumin, bis-demethoxycurcumin and new synthetic glucosyl-curcuminoids is reported.

The main target of this study is a high-level computational analysis of Curcumin, employing DFT approach with two different sets of basis functions (B3LYP/6-31G ∗ and B3LYP/6-311G ∗∗ ). Accurate quantum mechanical studies, both in vacuum and in methanol medium, are carried out with the aim to analyze the conformational equilibria, to find the most stable equilibrium structure and to define the nature of the molecular orbitals, fundamental to explain Curcumin binding characteristic. Our theoretical calculations, performed at B3LYP/6-31G ∗ and B3LYP/6-311G ∗∗ levels both in vacuum and in methanol medium, confirm that the keto-enolic forms are more stable than the di-keto one, whose extremely low population suggests that this structure should not influence Curcumin properties. Keto-enolic form C results the most stable, independently on calculation level and solvent (methanol) effect. HOMO and LUMO molecular orbitals are calculated for all the structures with the two sets of basis with very similar results. MEPs show that the negative charge is localized on the oxygen atoms, which, in the keto-enolic forms, point in the same direction enabling metal coordination. NMR, UV–vis and FT-IR experimental data are employed in the comparison with electronic and conformational properties of Curcumin resulting from theoretical calculations. The two different calculation levels (B3LYP/6-31G ∗ and B3LYP/6-311G ∗∗ ) give very similar results. Good linear correlations between the experimental 1 H and 13 C NMR chemical shifts ( δ exp ), in methanol- d 4 (MeOD) and DMSO- d 6 (DMSO), and calculated magnetic isotropic shielding tensors ( σ calc ) are found ( δ exp = a · σ calc + b ). A good prediction of UV–vis experimental maximum absorption ( λ max ) on the basis of conformer populations is obtained. A linear relation with a good correlation coefficient is observed plotting the FT-IR experimental wavenumbers vs . the calculated ones, allowing to predict FT-IR spectra.