In vitro efficacy of four insecticides against eggs of Tunga penetrans (Siphonaptera)

Systematic assessments of control measures against the jigger flea Tunga penetrans are scarce, and there are no published data available on the efficacy of environmental insecticides against immature stages. We tested four environmental contact insecticides used by Brazilian authorities for disease control (deltamethrin, bifenthrin, dichlorvos and etofenprox) against T. penetrans eggs. Eggs were reared in vitro. Hatch rates were observed under standardized conditions and compared to a control group (40 eggs in each group). No larvae hatched after treatment with the organophosphate dichlorvos (100% efficacy). The efficacies of the other products tested varied between 17% and 57%. The data show that the organophosphate dichlorvos had a good in vitro efficacy. The use of dichlorvos can be directed to typical spots where early stages of T. penetrans are expected, considering its toxicity. Disease control should also consist of prevention measures concerning housing and environmental conditions, veterinary and human health measures

Avaliação do potencial de um resíduo de mineração na liberação de potássio e outros nutrientes em dois solos do Submédio São Francisco.

O trabalho foi realizado com o objetivo de avaliar o potencial de um de um resíduo de mineração em liberar potássio e outros nutrientes para o solo em sistema de cultivos sucessivos

Conversando sobre Património Industrial e outras Histórias: palavras, espaços e imagens

O conjunto de entrevistas apresentadas neste livro procura dar uma nova visão acerca do património industrial. Com uma abordagem aos estudos e às trajectórias de diversos estudiosos do Brasil e de Portugal, aos percursos de formação de cada autor (a), às suas várias temporalidades e vinculações institucionais distintas, a obra valoriza as narrativas orais de quem viveu o processo de construção e consolidação dessa área de pesquisa nos dois países. O objectivo é contribuir para o debate complexo e contínuo sobre o património e possibilita uma ampliação do nosso entendimento dos modos como esta área se firmou e se vem afirmando em diversos espaços, dentro e fora das universidades

Bacterial diversity dynamics in microbial consortia selected for lignin utilization.

Abstract:Lignin is nature?s largest source of phenolic compounds. Its recalcitrance to enzymatic conversion is still a limiting step to increase the value of lignin. Although bacteria are able to degrade lignin in nature, most studies have focused on lignin degradation by fungi. To understand which bacteria are able to use lignin as the sole carbon source, natural selection over time was used to obtain enriched microbial consortia over a 12-week period. The source of microorganisms to establish these microbial consortia were commercial and backyard compost soils. Cultivation occurred at two different temperatures, 30°C and 37°C, in defined culture media containing either Kraft lignin or alkaline-extracted lignin as carbon source. iTag DNA sequencing of bacterial 16S rDNA gene was performed for each of the consortia at six timepoints (passages). The initial bacterial richness and diversity of backyard compost soil consortia was greater than that of commercial soil consortia, and both parameters decreased after the enrichment protocol, corroborating that selection was occurring. Bacterial consortia composition tended to stabilize from the fourth passage on. After the enrichment protocol, Firmicutes phylum bacteria were predominant when lignin extracted by alkaline method was used as a carbon source, whereas Proteobacteria were predominant when Kraft lignin was used. Bray-Curtis dissimilarity calculations at genus level, visualized using NMDS plots, showed that the type of lignin used as a carbon source contributed more to differentiate the bacterial consortia than the variable temperature. The main known bacterial genera selected to use lignin as a carbon source were Altererythrobacter, Aminobacter, Bacillus, Burkholderia, Lysinibacillus, Microvirga, Mycobacterium, Ochrobactrum, Paenibacillus, Pseudomonas, Pseudoxanthomonas, Rhizobiales and Sphingobium. These selected bacterial genera can be of particular interest for studying lignin degradation and utilization, as well as for lignin-related biotechnology applications

Effects of Brazil's political crisis on the science needed for biodiversity conservation

The effects of Brazil’s political crisis on science funding necessary for biodiversity conservation are likely to be global. Brazil is not only the world’s most biodiverse nation, it is responsible for the greater part of the Amazon forest, which regulates the climate and provides rain to much of southern South America. Brazil was a world leader in satellite monitoring of land-use change, in-situ biodiversity monitoring, reduction in tropical-forest deforestation, protection of indigenous lands, and a model for other developing nations. Coordinated public responses will be necessary to prevent special-interest groups from using the political crisis to weaken science funding, environmental legislation and law enforcement. Keywords: Brazil, biodiversity, climate change, governance, fundin