Impacts of hydropeaking: A systematic review.

Hydropower is commonly considered a renewable energy source. Nevertheless, this does not imply an absence of impacts on the riverine ecosystem, the extent of which is expected to increase in the coming years due to the energy transition from fossil fuels to renewable sources and for the climate change. A common consequence of hydroelectric power generation is hydropeaking, which causes rapid and frequent fluctuations in the water flow downstream of hydropower plants.

[Rare metastases].

The paper reports a number of cases of uncommon metastasis confirmed by histological tests in surgical biopsies; following a brief discussion of the literature on this topic and in particular on the basis of an earlier study by one of the authors, the paper affirms that metastasis is related to general and local biological factors, that the diffusion of neoplastic cells is an early and generalised phenomenon opposed by organic defence mechanisms, and that the concept of uncommon metastasis should be revised, without resorting to fixed anatomical references, according to a general "impregnation" of tumour cells.