Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Urbs e civitas: a formação dos espaços e territórios urbanos nas minas setecentistas

O presente artigo procura situar a evolução das abordagens acerca da cidade colonial mineira dentro da perspectiva mais ampla dos estudos sobre o urbanismo colonial português. A análise privilegia os trabalhos que, em vez de se aterem aos aspectos ligados à estética urbana, procuraram relacioná-los às questões fundiárias e à constituição das redes e hierarquias urbanas.This article seeks to situate the evolution of approaches to the study of the colonial towns of Minas Gerais placing them in the broader perspective of studies on the Portuguese colonial urbanism. Instead of restricting our approach to questions of urban aesthetics, the analysis focuses on the works that tried to relate these questions to aspects of land ownership and to the establishment of networks and urban hierarchies

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Produção biotecnologica de metilcetonas por linhagem de Aspergillus sp

Orientador: Glaucia Maria PastoreDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de AlimentosResumo: Foram estudados alguns parâmetros de processo para a produção de metilcetonas por uma nova linhagem de Aspergillus sp. pré-selecionada como produtora de lipase extracelular, ainda não relatada na literatura. Através da utilização da técnica de cromatografia gasosa acoplada a detetor seletivo de massas e de cálculo de índice de retenção, foram identificadas as quatro principais metilcetonas produzidas que são: 2-pentanona, 2-heptanona, 2-nonanona e 2-undecanona. As maiores concentrações de metilcetonas (2-pentanona, 2-heptanona, 2-nonanona e 2-undecanona) encontradas quando foi utilizado creme de leite de cabra foram: 0.5, 1.4, 2.4 e 0.4 mg/g de substrato respectivamente e de 0.3, 0.8, 1.04 e 0.22 mg/g de substrato quando se utilizou creme de leite de vaca. Creme de leite de cabra e creme de leite de vaca foram os dois substratos adequados para a produção das metilcetonas, devido a sua composição de ácidos graxos, sendo que, a maior concentração de ácidos graxos de cadeia média esteve presente no creme de leite de cabra e portanto foi obtida uma maior concentração de metilcetonas quando se utilizou este substrato. Foi observado que as melhores condições para produção de metilcetonas foram: período de incubação de 96 horas a 30°C, pH 4,5 e sistema de reação contendo uma mistura de lipase e esporos da linhagem n° 1099. Uma suspensão de lipase isenta de esporos foi incapaz de produzir metilcetonasAbstract: A newly strain of Aspergillus sp. which produced extracellular lipase was chosen to study some of the process parameters for the production of methyl ketones. Four methyl ketones (2-pentanone, 2-heptanone, 2-nonanone and 2undecanone) were identified from their retention indices and using a gas chromatograph equipped with a mass detector. Of the two substrates used (goat's milk cream and cow's milk cream) the best results were obtained with in the goat's milk cream. The reason for this behavior could be differences in the fatty acid composition of the two substrates. The high concentrations of methyl ketones (2-pentanone, 2-heptanone, 2-nonanone and 2-undecanone) observed were: 0.5, 1.4, 2.4 e 0.4 mg/l respectively, when goat's milk cream was used as substrate. When cow's milk cream was used, the concentrations of methyl ketones were: 0.3, 0.8, 1.04 e 0.22 mg/g respectively. The results suggest good conditions to produce methyl ketones in 96 hours of incubation at 30°C, pH 4,5 and a reaction system with a mixture of lipase and spores of strain n° 1099MestradoMestre em Ciência

Especiação redox de cromo em solo acidentalmente contaminado com solução sulfocrômica Crhomium redox specification in soil accidentally contamined with sulphochrinuc solution

<abstract language="eng">Determination of Cr(VI) and Cr(III) was studied in soil samples accidentally contaminated with sulphochromic solution. Molecular absorption spectrophotometry based on the diphenylcarbazide method was used for the determination of Cr(VI) after its alkaline extraction. The total chromium concentration was determined using ICP OES. The quantification of Cr(III) was accomplished by subtracting the Cr(VI) concentration from the total chromium concentration. Regardless of the known contamination of the soil samples by sulphochromic solution, concentrations of Cr(VI) were below the detection limit. Addition and recovery experiments for Cr(VI) in soil samples with and without organic matter indicated its influence on the reduction of Cr(VI) to Cr(III)