Multiscale methods for second order elliptic equations based on non-overlapping domain decomposition schemes have great potential to take advantage of multi-core, state-of-the-art parallel computers. These methods typically involve solving local boundary value problems followed by the solution of a global interface problem. Known iterative procedures for the solution of the interface problem have typically slow convergence, increasing the overall cost of the multiscale solver. To overcome this problem we develop a scalable recursive solution method for such interface problem that replaces the global problem by a family of small interface systems associated with adjacent subdomains, in a hierarchy of nested subdomains. Then, we propose a novel parallel algorithm to implement our recursive formulation in multi-core devices using the Multiscale Robin Coupled Method by Guiraldello et al. (2018) [26], that can be seen as a generalization of several multiscale mixed methods. Through several numerical studies we show that the new algorithm is very fast and exhibits excellent strong and weak scalability. We consider very large problems, that can have billions of discretization cells, motivated by the numerical simulation of subsurface flows.

Se a história da Metafísica é marcada por grandes transformações e mesmo reivindicações de revoluções ou revisões radicais de seus conceitos, foi em torno da noção de substância que essas mudanças muitas vezes se estabeleceram. Esperamos esclarecer a leitoras e leitores quais podem ser as marcas características da substância e por que filósofas e filósofos disputam tanto essa definição. Para explicar essa divergência, oferecemos uma apresentação organizada historicamente, mas focada nos elementos conceituais em jogo. Com efeito, não se tratará aqui de fixar datas, obras, nomes; mas antes de elaborar certas perspectivas que permitam balizar o percurso do pensamento até chegar a esta nossa época da qual, de tão perto que estamos dela, ainda não podemos oferecer uma caracterização precisa. Se selecionar e fixar marcos históricos será sempre uma tarefa eminentemente polêmica, leitoras e leitores da presente coletânea certamente perceberão que, a julgar pelas referências aqui privilegiadas, restam poucas dúvidas quanto às principais etapas da trajetória do conceito.

The present study analyzed how the economic, social and human mobility factors were responsible for dissemination of Covid -19 in Brazil and the Legal Amazon region. Human mobility was analyzed by four dimensions according to the network's hierarchies of: migration, pendular mobility, airlift, hydro and road routes and healthcare system. Manaus, capital of Amazon, was the first diffuser pole of cases; this may be explained by absence of public lockdown policies and restriction of mobility by river routes and airport system. In the face of the worsening of the pandemic, between March to May 2020, the previous migratory pattern of the urban population was accentuated to inland Amazonian cities that spread the virus towards remote areas of the Amazon. In addition, there was a pendular migratory movement to Manaus, which is the only center in the region with highly complex hospitals; this fact led to a strong migratory movement of populations seeking medical assistance. The analysis on migration revealed a close relation of the spatiotemporal behavior of Covid-19 spread and the migration network to Manaus. There were significant correlations related to fluvial or waterway transportation axis along the Amazon River which is the dominant route of the region. These pathways have long distances to be covered from one pole to another and were additional factors for the spread of the pandemic during the period studied and have long travel times that can be an important factor for COVID-19 further dissemination. We conclude that the wide dissemination of COVID-19 cases across the Legal Amazon was the result of multifactorial causes that include social inequities, vulnerability, high rate of mobility and migration, information failure and administrative and social management of the crisis.

At the beach, death assemblages are constantly reworked by wind and waves. One of the various consequences of this shore dynamic is the constant burial and exhumation of the shells, making them inappropriate for epibionts. However, some gastropod shells collected in the death assemblages arranged on the foreshore of the coastal plain of south Brazil were hardly encrusted. Olivancillaria urceus corresponds to 48.8% of all encrusted taxa, suggesting that some shell species may play a more striking role than others as available bioclasts. Therefore, the research aims to discuss the taphonomic implications for epibionts and bioerosion in gastropod shells. Abandoned gastropod shells were collected on 27 sites along a 150 km coastal strip in southernmost Brazil. Epibionts and bioerosion traces were identified, and their frequency was calculated considering their abundance, which taxa they occurred in, and their settlement on the different parts of the shells. At least 13 of 21 taxa were colonized by epibionts, of which 97% were by bryozoans. Other epibionts recognized were serpulid tubes, bivalves, and balanids. Fifteen taxa were bioeroded, showing traces made by worms (cf. Caulostrepsis), bryozoans (cf. Pennatichnus), balanids (cf. Rogerella), bivalves (cf. Gastrochaenolites), and sponges (cf. Entobia). The results reached in this survey suggest that the bryozoans have an advantage over other epibionts at colonizing the gastropod shells.