An efficient chronic unpredictable stress protocol to induce stress-related responses in C57BL/6 mice

Exposure to chronic stress can have broad effects on health ranging from increased predisposition for neuropsychiatric disorders to deregulation of immune responses. The chronic unpredictable stress (CUS) protocol has been widely used to study the impact of stress exposure in several animal models and consists in the random, intermittent, and unpredictable exposure to a variety of stressors during several weeks. CUS has consistently been shown to induce behavioral and immunological alterations typical of the chronic stress-response. Unfortunately C57BL/6 mice, one of the most widely used mouse strains, due to the great variety of genetically modified lines, seem to be resistant to the commonly used 4-week-long CUS protocol. The definition of an alternative CUS protocol allowing the use of C57BL/6 mice in chronic stress experiments is a need. Here, we show that by extending the CUS protocol to 8?weeks is possible to induce a chronic stress-response in C57BL/6 mice, as revealed by abrogated body weight gain, increased adrenals weight, and an overactive hypothalamic-pituitary-adrenal axis with increased levels of serum corticosterone. Moreover, we also observed stress-associated behavioral alterations, including the potentiation of anxious-like and depressive-like behaviors and a reduction of exploratory behavior, as well as subtle stress-related changes in the cell population of the thymus and of the spleen. The present protocol for C57BL/6 mice consistently triggers the spectrum of CUS-induced changes observed in rats and, thus, will be highly useful to researchers that need to use this particular mouse strain as an animal model of neuropsychiatric disorders and/or immune deregulation related to CUS.

Redes sociais, capital social e governança ambiental no Território Portal da Amazônia

O artigo trata de um estudo empírico em que a análise de redes sociais é utilizada para mapear o capital social de atores envolvidos em processos de governança ambiental na Amazônia brasileira. Por meio de entrevistas, foi mapeada a rede de relações de diálogo sobre questões socioambientais de um conjunto de 505 atores no Território Portal da Amazônia. Foram identificadas 3384 relações de diálogo, com uma média de 6,7 parceiros de diálogo por ator. A análise dos aspectos estruturais da rede de diálogo foi utilizada para construir indicadores de capital social de ligação, com mapeamento da organização interna dos atores de um mesmo município, e de conexão, com a caracterização das relações entre atores de municípios diferentes. Em nível municipal, a distribuição das duas formas de capital social permitiu caracterizar os grupos de atores de acordo com as suas atuações diferenciadas na governança ambiental do Território. Em nível territorial, o padrão de conectividade entre os 16 municípios mostra um equilíbrio entre as duas formas de capital social e revela o potencial de comunicação e organização dos atores, como demonstrado no exemplo dos projetos de Agendas 21 locais. Estes resultados demonstram como a análise de redes sociais pode contribuir na definição (ou redefinição) das fronteiras dos territórios de modo a incluir um conjunto de municípios cujos atores mantêm relações sociais efetivas. Ações de governança no Portal da Amazônia são propostas com potencial para fortalecer os processos de diálogo, diminuir os conflitos e promover o uso sustentável dos recursos naturais na Amazônia.

Consumption, wealth, stock and housing returns: evidence from emerging markets

We test the predictive ability of the transitory deviations of consumption from its common trend with aggregate wealth and labour income, cay, for both future equity and housing risk premia in emerging market economies. Using quarterly data for 31 markets, our country-level evidence shows that forecasting power of cay vis-à-vis stock returns is high for Brazil, China, Colombia, Israel, Korea, Latvia and Malaysia. As for housing returns, the empirical evidence suggests that financial and housing assets are perceived as complements in the case of Chile, Russia, South Africa and Thailand, and as substitutes in Argentina, Brazil, Hong Kong, Indonesia, Korea, Malaysia, Mexico and Taiwan. Using a panel econometric framework, we find that the cross-country heterogeneity observed in asset return predictability does not accrue to regional location, but can be attributed to differences in the degree of equity market development and in the level of income.

Silicon nanowire arrays coupled with cobalt phosphide spheres as low-cost photocathodes for efficient solar hydrogen evolution

We demonstrate the first example of silicon nanowire array photocathodes coupled with hollow spheres of the emerging earth-abundant cobalt phosphide catalysts. Compared to bare silicon nanowire arrays, the hybrid electrodes exhibit significantly improved photoelectrochemical performance toward the solar-driven H2 evolution reaction.

The efficient use of water in the context of climate change

Dissertação de mestrado integrado em Engenharia Civil

A carta do presidente e o relato voluntário do capital intelectual: análise das empresas do segmento do novo mercado da BM&FBOVESPA

Dissertação de mestrado em Contabilidade