Event Detection System Based on User Behavior Changes in Online Social Networks: Case of the COVID-19 Pandemic.

People use Online Social Networks (OSNs) to express their opinions and feelings about many topics. Depending on the nature of an event and its dissemination rate in OSNs, and considering specific regions, the users' behavior can drastically change over a specific period of time. In this context, this work aims to propose an event detection system at the early stages of an event based on changes in the users' behavior in an OSN.

The tadpole of Physalaemus orophilus from the Atlantic rainforest of southeastern Brazil (Amphibia, Anura, Leptodactylidae).

The neotropical genus Physalaemus Fitzinger is currently composed by 48 species (Cardozo Pereyra 2018). Recently, a phylogenetic analysis aiming to investigate the internal relationships of the genus recovered two major clades, the Physalaemus cuvieri and P. signifer clades (Lourenço et al.