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Rano Raraku, the crater lake constrained by basaltic tuff that served as the primary quarry used to construct themoaistatues on Rapa Nui (Easter Island), has experienced fluctuations in lake level over the past centuries. As one of the only freshwater sources on the island, understanding the present and past geochemical characteristics of the lake water is critical to understand if the lake could have been a viable freshwater source for Rapa Nui. At the time of sampling in September 2017, the maximum lake depth was ~1 m. The lake level has substantially declined in the subsequent years, with the lake drying almost completely in January 2018. The lake is currently characterized by highly anoxic conditions, with a predominance of ammonium ions on nitrates, a high concentration of organic carbon in the water-sediment interface and reducing conditions of the lake, as evidenced by Mn/Fe and Cr/V ratios. Our estimates of past salinity inferred from the chloride mass balance indicates that it was unlikely that Rano Raraku provided a viable freshwater source for early Rapa Nui people. The installation of an outlet pipe around 1950 that was active until the late 1970s, as well as grazing of horses on the lake margins appear to have significantly impacted the geochemical conditions of Rano Raraku sediments and lake water in recent decades. Such impacts are distinct from natural environmental changes and highlight the need to consider the sensitivity of the lake geochemistry to human activities.

Several products of metabolism and aromatic ring cleavage of 3-methoxy and 3,4-dimethoxycinnamic acid from ligninolytic cultures of Lentinus edodes were isolated and identified.

Statistics is assuming an increasing rule in the administration of justice. Scientific evidence is mostly presented at trial in terms of probabilities as measure of uncertainty. Handling probabilities may be an involving task, in particular with reference to complex cases that are characterized by multiple sources of uncertainty. The computation, presentation and interpretation of the probative value of the scientific evidence at trial may give rise to wrong considerations that might influence the final decision of a court. This has originated a large debate and this paper offers a general discussion about these aspects.

A brief outline of high-resolution infrared spectroscopy of gases will be given. Attention will be focused on rovibrational bands of asymmetric rotors and on the algorithms employed in spectral interpretation and in data analysis. The description of the tunable diode laser spectrometer of the molecular spectroscopy group of the University of Venice will be followed by the presentation of some of the results that have been achieved in the study of molecules of atmospheric interest. In particular, the ν6 band (C=CH deformation mode) of Vinyl-Chloride will be discussed for both natural and 37Cl isotopically enriched species. Examples of other information that can be derived from high-resolution infrared spectra will be given employing data from the ν5 band of CF2HCl and the ν4 band of CH2=CHF.