27 research outputs found
Metarhizium anisopliae blastospores are highly virulent to adult Aedes aegypti, an important arbovirus vector
BackgroundThe use of entomopathogenic fungi (EPF) for the control of adult mosquitoes is a promising alternative to synthetic insecticides. Previous studies have only evaluated conidiospores against adult mosquitoes. However, blastospores, which are highly virulent against mosquito larvae and pupae, could also be effective against adults.MethodsMetarhizium anisopliae (ESALQ 818 and LEF 2000) blastospores and conidia were first tested against adult Aedes aegypti by spraying insects with spore suspensions. Blastospores were then tested using an indirect contact bioassay, exposing mosquitoes to fungus-impregnated cloths. Virulence when using blastospores suspended in 20% sunflower oil was also investigated.ResultsFemale mosquitoes sprayed with blastospores or conidia at a concentration of 108 propagules ml−1 were highly susceptible to both types of spores, resulting in 100% mortality within 7 days. However, significant differences in virulence of the isolates and propagules became apparent at 107 spores ml−1, with ESALQ 818 blastospores being more virulent than LEF 2000 blastospores. ESALQ 818 blastospores were highly virulent when mosquitoes were exposed to black cotton cloths impregnated with blastospores shortly after preparing the suspensions, but virulence declined rapidly 12 h post-application. The addition of vegetable oil to blastospores helped maintain virulence for up to 48 h.ConclusionThe results showed that blastospores were more virulent to adult female Ae. aegypti than conidia when sprayed onto the insects or applied to black cloths. Vegetable oil helped maintain blastospore virulence. The results show that blastospores have potential for use in integrated vector management, although new formulations and drying techniques need to be investigated
A INCIDÊNCIA DE DENGUE ASSOCIADA A FATORES SOCIOECONÔMICOS NO MUNICÍPIO DE CAMPOS DOS GOYTACAZES - RJ
A dengue é considerada pela Organização Mundial de Saúde (OMS) uma arbovirose de maior relevância no mundo. O agente etiológico da doença é um vírus do gênero Flavivírus, pertencente à família Flaviridae e é classificado em quatro sorotipos (DENV 1-4). O mosquito vetor, Aedes aegypti, apresenta-se em grande parte do território nacional e isso se deve à urbanização acelerada, sem planejamento, característica dos centros urbanos de países em desenvolvimento. Sem vacina contra a dengue, o controle da população de A. aegypti torna-se importante. Levantamentos de incidência de dengue também podem direcionar os programas de controle do vetor para locais com maiores casos suspeitos e confirmados. O presente trabalho realizou um levantamento de incidência da doença dengue em 6 bairros de Campos dos Goytacazes, Estado do Rio de Janeiro, Brasil. Observou que os bairros com melhor infraestrutura e população com melhor renda a incidência de dengue foi significativamente baixa, comparado com bairros de periferia
Dinâmica do crescimento de árvores dominantes em povoamentos clonais de Tectona grandis Linn. F.
O objetivo deste trabalho foi avaliar a dinâmica das árvores dominantes na classificação da capacidade produtiva de sítios florestais e verificar se a estrutura sugerida por Schumacher é estatisticamente indicada para descrever o crescimento em altura dominante de árvores clonais de teca. Para este fim foram abordadas duas distintas formas de classificação de árvore dominante. Uma primeira que fixa estas árvores na primeira medição da parcela de inventário florestal, sendo, portanto, uma única classificação durante toda a rotação do povoamento. Uma segunda que classifica uma árvore dominante em cada medição da parcela, e posterior cálculo da altura médias das arvores dominantes. Nesta pesquisa os dados foram originados do monitoramento contínuo de 121 parcelas de campo, com idade variando de 1,1 a 8,1 anos, de plantios comerciais de Tectona grandis Linn. F, localizados na região centro-sul do estado de Mato Grosso. Para fins de comparação das duas abordagens do estudo, foram utilizadas as estatísticas de coeficiente de determinação (R²) e o erro padrão em escala percentual. As estatísticas dos modelos foram complementadas pela análise da estabilidade das parcelas na rotação do povoamento, e também pela identidade das curvas. As estatísticas de ambos os métodos de classificação foram muito próximas, com R² de 0,9950 e 0,9953, e erro padrão residual de 22,56 e 21,48%. Quanto à estabilidade, o modelo de Schumacher, para ambos os métodos, classificou como estável mais de 90% das parcelas utilizadas no estudo. E sobre a identidade das curvas, pôde-se inferir que ambas as curvas de sítios foram similares na classificação da capacidade produtiva. Portanto, foi possível concluir que não existe diferença estatística entre as curvas de sítios quando consideradas as diferentes classificações de árvores dominantes, o que comprova a hipótese de que árvores dominantes se mantém dominantes durante toda a rotação florestal
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
ATLANTIC-PRIMATES: a dataset of communities and occurrences of primates in the Atlantic Forests of South America
Primates play an important role in ecosystem functioning and offer critical insights into human evolution, biology, behavior, and emerging infectious diseases. There are 26 primate species in the Atlantic Forests of South America, 19 of them endemic. We compiled a dataset of 5,472 georeferenced locations of 26 native and 1 introduced primate species, as hybrids in the genera Callithrix and Alouatta. The dataset includes 700 primate communities, 8,121 single species occurrences and 714 estimates of primate population sizes, covering most natural forest types of the tropical and subtropical Atlantic Forest of Brazil, Paraguay and Argentina and some other biomes. On average, primate communities of the Atlantic Forest harbor 2 ± 1 species (range = 1–6). However, about 40% of primate communities contain only one species. Alouatta guariba (N = 2,188 records) and Sapajus nigritus (N = 1,127) were the species with the most records. Callicebus barbarabrownae (N = 35), Leontopithecus caissara (N = 38), and Sapajus libidinosus (N = 41) were the species with the least records. Recorded primate densities varied from 0.004 individuals/km 2 (Alouatta guariba at Fragmento do Bugre, Paraná, Brazil) to 400 individuals/km 2 (Alouatta caraya in Santiago, Rio Grande do Sul, Brazil). Our dataset reflects disparity between the numerous primate census conducted in the Atlantic Forest, in contrast to the scarcity of estimates of population sizes and densities. With these data, researchers can develop different macroecological and regional level studies, focusing on communities, populations, species co-occurrence and distribution patterns. Moreover, the data can also be used to assess the consequences of fragmentation, defaunation, and disease outbreaks on different ecological processes, such as trophic cascades, species invasion or extinction, and community dynamics. There are no copyright restrictions. Please cite this Data Paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data. © 2018 by the The Authors. Ecology © 2018 The Ecological Society of Americ
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
Geranyl acetate synthesis in a packed-bed reactor catalyzed by novozym in supercritical carbon dioxide and in supercritical ethane
The esterification reaction of geraniol with acetic acid (100 mM/100 mM) catalyzed by immobilized Candida antarctica lipase B (Novozym 435) was studied in supercritical carbon dioxide (sc-CO2) and in sc-ethane in a packed-bed reactor(PBR). In sc-CO2 it was easy to adjust the water activity (aw) in the reaction mixture to levels leading to good enzyme performance.
Enzyme stability was high and steady-state conversions could be achieved that exceeded the largest conversions measured in batch
stirred-tank reactors (BSTRs), which is probably due to the lower aw levels achieved in the PBR. In sc-ethane, where the solubility of water is lower, high steady-state conversions could be attained only by preventing the accumulation on the enzyme bed of the water produced during reaction. The kinetic parameters for the reaction in sc-CO2 were determined using previously published data obtained in a BSTR, and a model was developed for the PBR that included those kinetic parameters. This model was able to predict with reasonable accuracy the behavior of the PBR. Slight differences were observed for some operating regions, probably due to the influence of aw in the activity of the enzyme, which is not included in the model.This work was supported by Fundação para a Ciência e Tecnologia (FCT, Portugal) through grants SFRH/BD/13084/2003 (A.S.R.) and SFRH/BPD/41546/2007 (P.V.), FEDER, and by the European Commission in the framework of the Marie Curie Research Training Network “Green Chemistry in Supercritical Fluids: Phase Behaviour, Kinetics and Scale-up” (EC Contract No. MRTN-CT-2004-504005). We thank Novo Nordisk Bioindustrial, Spain, for the gift of Novozym 435
Geranyl Acetate Synthesis in a Packed-Bed Reactor Catalyzed by Novozym in Supercritical Carbon Dioxide and in Supercritical Ethane
The esterification reaction of geraniol with acetic acid (100 mM/100 mM) catalyzed by immobilized Candida antarctica lipase B (Novozym 435) was studied in supercritical carbon dioxide (sc-CO2) and in sc-ethane in a packed-bed reactor (PBR). In sc-CO2 it was easy to adjust the water activity (a(w)) in the reaction mixture to levels leading to good enzyme performance. Enzyme stability was high and steady-state conversions could be achieved that exceeded the largest conversions measured in batch stirred-tank reactors (BSTRs), which is probably due to the lower a(w) levels achieved in the PBR. In sc-ethane, where the solubility of water is lower, high steady-state conversions could be attained only by preventing the accumulation on the enzyme bed of the water produced during reaction. The kinetic parameters for the reaction in sc-CO2 were determined using previously published data obtained in a BSTR, and a model was developed for the PBR that included those kinetic parameters. This model was able to predict with reasonable accuracy the behavior of the PBR. Slight differences were observed for some operating regions, probably due to the influence of aw in the activity of the enzyme, which is not included in the model
Modeling growth of total height using early data from forest inventories in fast growing Eucalyptus spp plantations
This work evaluated the growth trend represented by three biological models used for modeling forest growth and production (Schumacher; Chapman-Richards; Logistic). These curves were chosen because they are widely used by forest science professionals. The functions were adjusted under the hypothesis that there is influence of the initial, 6 and 12 month measurements on the shape of the production curves and, consequently, in the estimate of their parameters. The data that formed the adjustment basis were generated by the continuous monitoring performed at 6, 12, and 24 months and later at each 12 months in order to yield the growth patterns for the evaluated plantations. The results herein presented allow us to conclude that independently of the type of adjustment, the Chapman-Richards function was the one that exhibited the best statistics, with the BIAS values reduced in up to 30% when compared to the others. The Schumacher function presented the worst performance among the proposed criteria in this study. So, given the results obtained, we suggest a broader reflection about the growth and production issue, especially for the use of biometric models applied to forest production forecast, in which stability and adherence of the curves to the data are expectedNeste trabalho foi avaliada a tendência de crescimento representada por três modelos biológicos empregados na modelagem do crescimento e da produção florestal (Schumacher; Chapman-Richards; Logística). Optou-se por estas curvas por serem amplamente utilizadas por profissionais da ciência florestal. As funções foram ajustadas sob a hipótese de que há influência das medições iniciais, 6 e 12 meses, no formato das curvas de crescimento para a altura média do povoamento, e por consequência na estimativa de seus parâmetros. Os dados, que compuseram a base de ajuste foram originados do monitoramento contínuo realizado aos 6, 12, 24 meses e posteriormente a cada 12 meses de forma a gerar os padrões de crescimento para a variável analisada. Os resultados permitiram inferir que independente da forma de ajuste, a função de Chapman-Richards foi a que apresentou as melhores estatísticas, com valores de BIAS reduzidos em até 30% quando comparada às demais. A função de Schumacher foi a que apresentou o desempenho menos satisfatório dentre os critérios propostos no estudo. E assim, diante dos resultados obtidos, sugerimos uma reflexão mais ampla acerca do tema crescimento e produção, em especial, para o uso de modelos biométricos aplicados em projeções da produção florestal, em que, se expecta estabilidade e aderência das curvas aos dado