The 1997 Kyoto International Conference Protocol committed industrialized countries to reduce their global emissions of greenhouse gases within the period 2008 2012 by at least 5% with respect to 1990. In view of this and following the European Community directives, the Italian government approved a three-year pilot project to promote the experimental employment of biodiesel. The methyl esters of vegetable oils, known as biodiesel are receiving increasing interest because of their low environmental impact and their potential as an alternative fuel for diesel engines as they would not require any significant modification of existing engines. Consequently, an experimental research program has been developed to evaluate performance and emissions of a Diesel engine fueled with a methyl ester derived from rape seed (Rapeseed Methyl Ester or RME) by changing the composition of the diesel fuel-RME mixture. This program aims to analyze the performance and emissions of a turbocharged D.I. Diesel engine fueled with a mixture of RME and diesel fuel. In particular, the experimental investigation has performed a careful analysis of heat release, which has made it possible to give more precise information about the combustion process.

Crenothrix polysporaCohn 1870 andClonothrix fuscaRoze 1896 are two filamentous, sheathed microorganisms exhibiting complex morphological differentiation, whose phylogeny and physiology have been obscure for a long time due to the inability to cultivate them. Very recently, DNA sequencing data from unculturedC. polyspora-enriched material have suggested thatCrenothrixis a methane-oxidizing γ-proteobacterium (39). In contrast, the possible ecological function ofC. fusca, originally considered a developmental stage ofC. polyspora, is unknown. In this study, temporal succession of two filamentous, sheathed microorganisms resembling Cohn'sCrenothrixand Roze'sClonothrixwas observed by analyzing the microbial community of an artesian well by optical microscopy. Combined culture-based and culture-independent approaches enabled us to assignC. fuscato a novel subgroup of methane-oxidizing γ-proteobacteria distinct from that ofC. polyspora. This assignment was supported by (i) methane uptake and assimilation experiments, (ii) ultrastructural data showing the presence inC. fuscacytoplasm of an elaborate membrane system resembling that of methanotrophic γ-proteobacteria, and (iii) sequencing data demonstrating the presence in its genome of a methanol dehydrogenase α subunit-encoding gene (mxaF) and a conventional particulate methane mono-oxygenase α subunit-encoding gene (pmoA) that is different from the unusualpmoA(u-pmoA) ofC. polyspora.