V. Piscopo

Structural determination of the complex exopolysaccharide from the virulent strain of Cryphonectria parasitica

The structure of a new exopolysaccharide from the virulent strain of Cryphonectria parasitica was elucidated by means of 2D NMR spectroscopy and selective degradations (mild hydrolysis and acetolysis). The polysaccharide is built up of mannose, galactose and rhamnose and has a rather complex non-repetitive structure that can be idealised as follows:

Acetyl substitution of the O-specific polysaccharide caryophyllan from the phenol phase of Pseudomonas (Burkholderia) caryophylli

The intact O-specific caryophyllan polysaccharide of the lipopolysaccharide fraction from the bacterium Pseudomonas (Burkholderia) caryophylli was isolated for the first time. Its structure was clarified by means of chemical and spectroscopic analysis and consisted of a homopolymer of randomly acetylated caryophyllose units. The position of acetyl groups when present is not unique: all the hydroxyl-groups on the side chain of the sugar can be substituted with a slight preference for acetylation of the C-5-C-10 tail of this unusual monosaccharide

Optimization of Mooring Systems for Floating Offshore Wind Turbines

The paper deals with the optimum design of mooring systems, with chain cable catenary line configuration, for Floating Offshore Wind Turbines with tri-floater support structure in deep waters. Operational and extreme climate conditions are assessed for a candidate location in southern Tyrrhenian Sea, determining wind, wave and current loads. The platform response is assessed in terms of static loads due to turbine thrust, wind, current and steady drift forces. The platform dynamic offset is determined considering both wave-frequency linear and low-frequency second-order motions. Two different mooring systems with 9 (equally spaced) and 11 (non-uniformly spaced) lines are selected in order to minimize the total mass; the incidence of both line number and pattern is appreciable and there is wide space to achieve considerable weight reductions, so increasing the overall wind farm cost-performance trade-off.

Observed and calculated 1H- and 13C-NMR chemical shifts of substituted 5H-pyrido[3,2-a]- and 5H-pyrido[2,3-a]phenoxazin-5-ones and of some 3H-phenoxazin-3-one derivativesElectronic supplementary information (ESI) available: 1H and 13C NMR data for compounds 1?17. See http://www.rsc.org/suppdata/ob/b4/b401147c/

Carbon and proton NMR spectra of several substituted 5H-pyrido[3,2-a]-, 5H-pyrido[2,3-a]phenoxazin-5-ones and 3H-phenoxazin-3-one derivatives have been assigned, and the experimental chemical shifts have been compared with the results of density functional calculations employing large basis sets. Solvent effects were explored by means of the polarizable continuum method (PCM), while the (limited) side-chain flexibility of the compounds has been addressed by Boltzmann averaging of the computed spectral parameters over different conformational minima. Overall, the calculated shifts reproduce well the experiment results; thus, the computational procedure represents a feasible and useful complement to multidimensional NMR experiments in the assignment process.

The overall motion sickness incidence applied to catamarans

Abstract The Overall Motion Sickness Incidence is applied to the hull form optimization of a wave piercing high-speed catamaran vessel. Parametric hull modelling is applied to generate two families of derived hull forms, the former varying the prismatic coefficient and the position of longitudinal centre of buoyancy, the latter instead the demi-hull separation. Several heading angles are analysed in a seaway, considering all combinations of significant wave height and zero-crossing period under two operating scenarios. The optimum hull is generated and vertical accelerations at some critical points on main deck are compared with the parent ones. Finally a comparative analysis with the results obtained for a similarly sized monohull passenger ship is carried out, in order to quantify, by the OMSI, the relative goodness in terms of wellness onboard of monohulls and catamarans, as a function of sea states and operating scenarios.