Aquest estudi presenta dades amb l’objectiu d’analitzar les expectatives educatives i ocupacionals dels estudiants immigrants de classe treballadora que varen participat en un programa de mentoria en el passat. Per tal de realitzar un seguiment longitudinal d’estudi de cas dels mentors, els adolescents immigrants van ser enquestats abans i després de participar en el programa i de nou quatre anys després. Les dades de les entrevistes en profunditat mostren com les expectatives dels mentorats es troben condicionades pel paper del mentor o d’altres adults significatius. Els resultats suggereixen la qualitat de la relació, el paper actiu dels mentors com a agents institucionals, la manera com els mentors van proporcionar habilitats de capital social als estudiants i la manera com els mentors van tractar el llenguatge del nou context d’acollida com a trets clau per a l’apoderament dels estudiants.

Eucalyptus nitens is a fast growing plantation species that has a good acclimation in Spain and Chile. At the moment it is mainly used for pulp and paper production, but there is a growing market for solid wood products made from this species. Thermal modification offers a good alternative to produce high quality material to manufacture products with high added value. This study used unmodified and thermally modified E. nitens wood from Spanish and Chilean plantations to elaborate external decking and examine if it complies with the necessary properties to be a competitive product. A process similar to ThermoWood® was applied at the following temperatures: 185 °C, 200 °C and 215 °C. For each modification and for an unmodified specimen mass loss, volumetric swelling, anti-swelling efficiency (ASE) and equilibrium moisture content (EMC) were determined. Brinell hardness, dynamic hardness, screw and nail withdrawal resistance, and abrasion resistance according to the Shaker method and the Taber Abraser method were also determined. According to this study, thermally modified E. nitens from both countries showed high potential to be used as decking material, particularly when modified at 200 °C.

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Many thermal and chemical treatments are known to inhibit wood decay despite the wood grade processed, but their impact, e.g., chemicals’ leaching and decay resistance, may not be similar. The aim of this study was to test whether some model treatments retain their performance in different wood species. Additionally, the effects of thermal modification and linseed oil-based varnish treatments as means to mitigate water-soluble chemicals leaching were assessed. The mass loss caused by Trametes versicolor was measured after a 12-week exposure to analyze whether the different treatment approaches prevented the fungal decay after a standard leaching test. The mechanical properties before and after exposure were tested independently to determine whether the mechanical properties of different wood species were affected by the tested treatments and wood decay. The responses of the tested wood species were found to vary by treatments, but thermal and chemical fixation methods for water-soluble tannins were beneficial in all cases considering the mass loss and the degradation of modulus of rupture and modulus of elasticity of treated wood. Varnish was overall the most effective treatment against decay, but the results emphasize the need for testing potential preservation methods and chemicals on several species.

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