RESUMO
The outbreak and propagation of COVID-19 have posed a considerable challenge to modern society. In particular, the different restrictive actions taken by governments to prevent the spread of the virus have changed the way humans interact and conceive interaction. Due to geographical, behavioral, or economic factors, different sub-groups among a population are more (or less) likely to interact, and thus to spread/acquire the virus. In this work, we present a general multi-group SEIRA model for representing the spread of COVID-19 among a heterogeneous population and test it in a numerical case of study. By highlighting its applicability and the ease with which its general formulation can be adapted to particular studies, we expect our model to lead us to a better understanding of the evolution of this pandemic and to better public-health policies to control it.
RESUMO
Two new species of Collembola are described, full body chaetotaxy is given. Ptenothrix dalii sp. nov. and Seira pietata sp. nov. were originally found in metalogenic areas covered with transitional vegetation of savanna and forest in Minas Gerais, Southeastern Brazil. Ptenothrix dalii sp. nov. is part of the "gracilis-group" of species, with large, blunt macrochaetae on head and body. Seira pietata sp. nov. is part of the "andensis-group" of species, lacking macrochaeta on abdominal segment I.
Assuntos
Insetos/anatomia & histologia , Insetos/classificação , Animais , Brasil , Cavernas , FlorestasRESUMO
Herein Lepidocyrtinus Börner is reviewed based on African species and a new diagnosis to the genus is provided, including the description of intermediary stages of two species and a proposal for the interpretation of the dorsal chaetotaxy based in juveniles. In total, 17 species previously assigned as Seira Lubbock are transferred to Lepidocyrtinus, and three of them are redescribed: L. barnardi Womersley and L. dayi Yosii from South Africa, and L. voeltzkowi (Börner) from Madagascar. Neotypes are designated for these last two species. In addition, nine new species are described from Africa: one from Botswana, two from Republic of the Congo, two from South Africa, and four from Madagascar. Finally, identification keys for the current genera of Seirinae and for the African species of Lepidocyrtinus are provided. After our revision, Lepidocyrtinus has now its generic status revalidated with 36 species, 29 of them from African continent, two from Oceania and five from Brazil.