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Wood-decay fungi have been mainly studied for their medicinal or nutraceutical properties, lignocellulolytic enzymes as well as their pathological role in plants. Recently they have also been recognized as a potential source of biocomposite materials due to the features of mycelial mats in several species. Chemical, physical-morphological and biological properties are affected by interspecific and intraspecific differences in composition of the cell wall regarding both major and minor constituents; thus, a preliminary characterization can optimize the strain selection for applied and research purposes. In the present study, 52 strains from 18 wood-decay fungal species were considered to build a general descriptive model based on the cell wall in the light of interspecific variability. Pure-cultured mycelia were dried and examined by thermogravimetric analysis (TGA) and Fourier transformed infrared spectroscopy (FTIR) to highlight the main different characteristics of each species. TGA profiles resulted more functional for a qualitative-quantitative description of major constituents (above all, β-glucans and chitin), whereas FTIR spectra are only qualitative and more difficult to analyze. Principal component analysis and cluster analysis confirmed the general descriptive model and allow interspecific comparison beyond intraspecific variability. In conclusion, TGA provides a simpler tool for screening of wood decay fungal strains and selection based on major cell wall constituents, namely chitin and glucans. [ABSTRACT FROM AUTHOR]

This study was the first to investigate the direct effects of anomalous concentrations of ozone mediated by summer heat waves on seed germination in alpine plants. During germination, the seeds were exposed to three peaks of O3concentration (125 ppb for 5 and 10 days; 185 ppb for 5 days), derived from measurements taken close to the species growing site. High O3concentration delayed the first germination time, increased the mean germination time, and reduced the germination percentage during and immediately after the treatment, but, in most cases, effects were weak and had almost vanished three weeks after the treatments. In few cases, chronic exposure to O3(125 for 10 days’ treatment) enhanced seed germination compared to the control, suggesting that ozone may induce antioxidant and DNA-repair mechanisms or dormancy-breaking effects in hydrated seeds. Although seed mortality increased during O3treatments in four species, the effect of O3on seed germination is mostly limited to the period of exposure, indicating that it is unlikely to produce permanent negative effects on seeds, during the germination phase. Our results show that the direct effect of O3on seeds of alpine plants may have minor impacts on plant reproductive performance during seed germination. [ABSTRACT FROM PUBLISHER]

Purpose: Disposal of sewage sludge is becoming one of the most important issues in wastewater treatment: the 2005 EU sludge production was estimated at 9.5 million tons dry weight, up 54 % in 10 years. Sludge disposal costs may constitute 30-50 % of the total operation cost of WWTPs. Sewage sludge still contains resources that may be put to use, like nutrients and energy, that can be recovered through a variety of approaches. Methods: Pyrolysis is a thermochemical decomposition process occurring by applying heat in absence of oxidizing agents; this way, chemical bonds are broken, with formation of simpler molecules, producing solid, gaseous and oil fractions that can be used as fuel or as prime material for chemical products. By applying microwave heating to achieve pyrolysis to the sludge under treatment, the more desirable production oil and gas fractions is increased and the residual solid fraction decreases. Results: Microwave-assisted pyrolysis of urban waste sludge was applied for the production of oil and (Syn)gas, that were afterwards characterized and compared to mainstream alternative fuels (biodiesels). An energetic estimate of the process is performed and described. A key factor in deciding the positivity of the energetic balance (and therefore the economic validity of the process) is the correct 'tuning' between microwave source and treated sample. Conclusions: Based on our tests, the overall energy balance of the process is not always immediately favorable, however, by appropriately 'tuning' the wave source and minimizing reflected radiation (lost energy) an energy-positive recovery of resources on one side, and considerable reduction of sludge volumes, on the other, may be achieved. [ABSTRACT FROM AUTHOR]

This paper reports on results obtained by electron paramagnetic resonance (EPR) measurements and Monte Carlo (MC) simulation on a blend of alanine added with low content of gadolinium oxide (5 % by weight) to improve the sensitivity to thermal neutron without excessively affecting tissue equivalence. The sensitivity is enhanced by this doping procedure of more an order of magnitude. The results are compared with those obtained with the addition of boric acid (50 % by weight) where boron is in its natural isotopic composition in order to produce low-cost EPR dosemeters. The gadolinium addition influences neutron sensitivity more than the boron addition. The presence of additives does not substantially change the fading of the EPR signal induced by neutrons. The MC simulations agree the experimental results in case of gadolinium addition. [ABSTRACT FROM AUTHOR]

This paper continues analyses on organic compounds for application in neutron dosimetry performed through electron spin resonance (ESR). Here, the authors present the results obtained by ESR measurements of a blend of ammonium tartrate dosemeters and gadolinium oxide (5 % by weight). The choice of low amount of Gd is due to the need of improving neutron sensitivity while not significantly influencing tissue equivalence. A study of the effect of gadolinium presence on tissue equivalence was carried out. The experiments show that the neutron sensitivity is enhanced by more than an order of magnitude even with this small additive content. Monte Carlo simulations on the increment of energy release due to gadolinium presence were carried, and the results were in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

Information concerning the interface structure in filler/polymer composites is of key importance for the rationalization of reaction mechanisms in mechano-chemical (extrusion, blending, etc.), thermal or radiation induced free radical processes and for elucidating the factors underlying the reinforcing mechanism. The analysis of the chain dynamics is a suitable tool for undertaking such investigations because any reactivity parameter (rate constants, collisional frequencies, activation energies) and bonding interactions are strictly related to the mobility of the interacting centres. EPR spectroscopy coupled with specific spin labelling at the filler/polymer interface is a tool for making such novel perspective available. In this work, a spin labelling study of the molecular motion at the filler-rubber interface in a silica-SBR blend is reported. Spin labels of different length, spanning a 9-11 Å depth and linked to the surface of silica particles, were prepared and used for determining the rotational diffusion tensors, the T50 and order parameter in silica/SBR interfaces. The measurements carried out as a function of the temperature in comparison with unbound spin probes dispersed in the rubber matrix have afforded information consistent with the structure of the interfaces predicted by molecular-level theoretical models. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]