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We propose a new technique to measure the angle of a remote flat surface with respect to the propagation direction of a laser beam, based on injection detection in a laser diode. The surface under test acts as the remote mirror of an external cavity laser, and causes the laser diode to operate in the coherent collapse regime. The power emitted by the laser depends on the alignment of the remote surface, and an ac technique enables us to measure angle with a sensitivity of 0.1 arcsec (i.e., 5ϫ10 Ϫ7 rad). The attained performances are comparable to those of existing autocollimators, with the advantage of simplicity and compactness that makes the new technique interesting for the development of a measuring instrument.

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Hydrogen sulfide (H2S), known for many decades exclusively for its toxicity and the smell of rotten eggs, has been re-discovered for its pleiotropic effects at the cardiovascular and non-cardiovascular level. Therefore, great attention is being paid to the discovery of molecules able to release H2S in a smart manner, i.e., slowly and for a long time, thus ensuring the maintenance of its physiological levels and preventing “H2S-poor” diseases. Despite the development of numerous synthetically derived molecules, the observation that plants containing sulfur compounds share the same pharmacological properties as H2S led to the characterization of naturally derived compounds as H2S donors. In this regard, polysulfuric compounds occurring in plants belonging to the Alliaceae family were the first characterized as H2S donors, followed by isothiocyanates derived from vegetables belonging to the Brassicaceae family, and this led us to consider these plants as nutraceutical tools and their daily consumption has been demonstrated to prevent the onset of several diseases. Interestingly, sulfur compounds are also contained in many fungi. In this review, we speculate about the possibility that they may be novel sources of H2S-donors, furnishing new data on the release of H2S from several selected extracts from fungi.