The hygroscopicity and thermodynamic properties of juvenile Pinus sylvestris L. wood taken from the submerged piles of a bridge built in 1903 over the Jiloca River, in Spain, were compared with the corresponding values of juvenile wood of the same species from recently cut trees. The 35°C and 50°C isotherms were plotted and subsequently fitted using the Guggenheim-Anderson-Boer-Dent method, and the isosteric heat of sorption was obtained through the integration method of the Clausius-Clapeyron equation. The isotherms were compared by means of the hysteresis coefficients. Infrared spectra were recorded to study the chemical modifications, and the crystal structure of the cellulose was studied by X-ray diffractograms. The submersion in water resulted in hemicellulose degradation and a decrease in the crystallinity index and the crystallite length, accompanied by a corresponding increase in the proportion of amorphous zones. Owing to this, the equilibrium moisture contents of the water logged wood are higher than in the recent wood, both in adsorption and in desorption. In terms of the thermodynamic properties, the bond energy is higher in the recent wood than in the water logged wood.

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The production of single-and multi-photon events has been studied in the reaction e + e − → γ(γ) + invisible particles. The data collected with the DELPHI detector during the years 1999 and 2000 at centre-of-mass energies between 191 GeV and 209 GeV was combined with earlier data to search for phenomena beyond the Standard Model. The measured number of light neutrino families was consistent with three and the absence of an excess of events beyond that predicted by the Standard Model processes was used to set limits on new physics. Both model-independent searches and searches for new processes predicted by supersymmetric and extra-dimensional models have been made. Limits on new non-standard model interactions between neutrinos and electrons were also determined.

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The Spanish populations of Pinus sylvestris L. occupy differentiated sites and must therefore include structural variations to cope with varied climate conditions. This study compares wood anatomical traits of P. sylvestris from ten Spanish regions of provenance with contrasting climates, taking into account the effects of region of provenance and tree nested within provenance on variation in wood biometry. In general, the effect of both sources of variation (provenance and tree) on wood biometry was highly significant. Most of the anatomical variations observed were intra-populational (at the tree level), although variation explained by provenance was high for some parameters (e.g., ray frequency and ray parenchyma cell frequency), suggesting high environmental influence. Trees in the driest region, growing in a Mediterranean phytoclimate, were characterized by large tracheid lumens, suggesting more efficient water conduction. They also had thick cell walls, which would reduce the risk of cavitation caused by high implosion stress during periods of drought, as well as a high ray tracheid frequency, implying greater water storage capacity in the sapwood. The population with greatest growth, located in an oroboreal phytoclimate, was characterized by large bordered pits and long tracheids, which would reduce resistivity in water transport. At higher altitudes, tracheid lumen diameter and resin canal diameter tended to be smaller, and intertracheid wall strength was greater. Results are discussed in relation to adaptation of the species to growth demands and frost.

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