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Four novel seconeodolastane diterpenoids, named tricholomalides D–G, were isolated, together with the known tricholomalide C, from the fruiting bodies of Tricholoma ustaloides Romagn., a species belonging to the large Tricholoma genus of higher mushrooms (Basidiomycota, family Tricholomataceae). They were isolated through multiple chromatographic separations, and the structures, including the absolute configuration, were established through a detailed analysis of MS, NMR, and CD spectral data and comparison with related compounds reported in the literature, which has been thoroughly revised.

The secondary metabolites produced by Tricholoma ustaloides Romagn., a mushroom species belonging to the large Tricholoma genus (Basidiomycota, Tricholomataceae), are unknown. Therefore, encouraged by the interesting results obtained in our previous chemical analyses of a few Tricholoma species collected in Italian woods, we aimed to investigate the secondary metabolites of Tricholoma ustaloides. The chemical analysis involved the isolation and characterization of secondary metabolites through an extensive chromatographic study. The structures of isolated metabolites, including the absolute configuration, were established based on a detailed analysis of MS, NMR spectroscopic, optical rotation, and circular dicroism data, and on comparison with those of related compounds reported in the literature. Two novel lanostane triterpenoids, named tricholidic acids B and C, together with triglycerides, a mixture of free fatty acids, five unidentified metabolites, and the known rare saponaceolides F and J, tricholidic acid, and tricholomenyn C, were isolated from an EtOAc extract of fruiting bodies of Tricholoma ustaloides that were collected in an Italian beech wood. This is the second example of isolation of tricholidic acid derivatives from a natural source. Saponaceolides F and J exhibited high cytotoxicity (IC50 values ≤ 10 μM) against a panel of five human cancer cell lines. The toxicity against myeloid leukemia (HL-60), lung cancer (A-549), hepatocellular cancer (HepG2), renal cancer (Caki-1), and breast cancer (MCF-7) cells was higher than that shown by the very well-known cytotoxic drug cisplatin.

Giorgio Errera (1860-1933) studied chemistry at the university of Torino in the research group of Michele Fileti, a very well-known organic chemist that had a great influence on him. After the degree he remained to work in the same Institute. Working very hard could publish many papers that allow him to get the “libera docenza” and therefore to teach in different courses as for example General Chemistry, Optics in chemistry a new subject. In 1892 won a chair at the university of Messina. Most of his published research results have been done in Messina and he became a very well-known chemist not only in Italy. However, at the end of 1908 an earthquake destroyed the town, and he lost his wife, the house and everything in the university. In the following years 1909-1917 he was professor at the university of Palermo and in 1917-1931 at the university of Pavia, where he published important books of Inorganic and Organic Chemistry. He was antifascist and had a very liberal mind so that in 1923 he refused to be appointed rector of the university and then, in 1931, he refused to swear to fascism and was forced to ask to be retired. He died two years later.

Abstract Previously, it was isolated from the fruiting bodies of the gilled mushroom Pholiota spumosa (Basidiomycetes, Strophariaceae), putrescine-1,4-dicinnamide, a phenylpropanoid derivative conjugated with polyamine putrescine never isolated before as a [...]

The Namie (Japan) 2016.11.21 M w 6.9 earthquake (d = 9.0 km) initiated a tsunami which, contrary to forecasts of up to 3 m based on preliminary earthquake magnitude, nowhere exceeded 1.4 m. The hypocentre of the main shock was bordered in the succeeding 24 h by a tight cluster of 24 M ≤4.5 shallow (d ≤ 20 km) earthquakes. Two of them nucleated close to a M4.6 tremor that had preceded the main earthquake by 2.34 h, raising the possibility that a single structure hosted all three. Granted the ultimate cause was subduction at the Japan Trench, these events reaffirm the need for focused seafloor monitoring and fault history to supplement teleseismic data for realistic tsunami forecasting. Earthquake clustering in the 24 h after the main earthquake may also reflect a mode of megathrust segmentation which discourages the generation of great (M w ∼ 9) earthquakes. [ABSTRACT FROM AUTHOR]

The M w 7.7 earthquake that struck SE Pakistan on 24 September 2013 at 11.29.48 UTC was a sinistral strike-slip event on a branch of the Ornach-Nal-Chaman fault system which hereabouts separates the Eurasian Plate from the Indian Plate. Although the focus was at a depth of 15 km and 400 km inland the earthquake was accompanied by the emergence of an island off the Makran coast and the generation of a tsunami with a peak amplitude of 27 cm at Muscat (Oman) and 20 cm at Chah Bahar (Iran). At DART marine buoy 23228 in the Indian Ocean 500 km to the south a series of seismic Rayleigh waves about 4 min after the main shock was followed 54 min later by a tsunami with a peak amplitude of 1 cm. The Rayleigh series is here attributed to seafloor vibration during accelerated subduction of the Arabian Plate beneath the Eurasian Plate, and the tsunami to the development or reactivation of one or more reverse faults on the seaward portion of the Makran imbricate fan. As in the 2010.2.27 M w 8.8 Maule (Chile), the 2004.12.26 M w 9.2 Sumatra–Andaman, the 2005.3.28 M w 8.7 Nias (Indonesia) and the 2011.3.11 M w 9.0 Tohoku (Japan) earthquakes, the link between tsunami generation and slip on the megathrust is thus very indirect, to the detriment of attempts to mitigate coastal hazards using teleseismic data when nearshore seafloor monitoring would probably prove more effective. [ABSTRACT FROM AUTHOR]

Abstract: Tsunami intensity is poorly correlated with earthquake magnitude. The distribution of aftershocks that immediately followed the 2010 Maule (Chile), the 2004 Sumatra–Andaman and the 2005 Nias (Indonesia) events supports the view that faulting within an accretionary wedge or an outer rise can sometimes disrupt the seafloor more effectively than a megathrust even if the associated seismicity is minor. Monitoring offshore faults would thus seem an effective way to supplement modes of tsunami early warning which hinge on instrumental earthquake detection or wave height and period. [Copyright &y& Elsevier]

The recurring mismatch between the magnitude of subduction earthquakes and related tsunamis hinders hazard assessment. A tsunami which accompanied the 2014.04.01 M w 8.2 Iquique earthquake and attained ≤2.11 m on the north Chilean coast is generally attributed to slip at a depth of 23 km on the megathrust between the Nazca and South American plates but, as at some other such sites, elastic seafloor deformation resulting from interplate displacements may have been supplemented if not overshadowed as the primary tsunamigenic agent by upper plate faulting. The evidence for suitable structures includes foreshocks M ≤ 5.8 dating from the preceding month and, during the 24 h immediately after the main shock, aftershocks M ≤ 5.6. [ABSTRACT FROM AUTHOR]

Like the tsunamis that accompanied the 2010 Maule (Chile) and the 2004 Sumatra-Andaman and 2005 Nias earthquakes, the tsunamis associated with the Tōhoku, Japan (Mw9.0), earthquake of 11 March 2011 may owe more to slip on superficial faults on the sea floor than to the megathrust itself. The pattern of shallow aftershocks during the 24h immediately following the main shock suggests that the crucial structures include faults in the upper plate, in the accretionary wedge landwards of the trench and on the outer rise. Seafloor geodetic observation could thus usefully contribute routinely to local hazard preparedness. [ABSTRACT FROM AUTHOR]