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1.
Sci Rep ; 9(1): 5136, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30914753

RESUMO

Genome size is known to vary widely across plants. Yet, the evolutionary drivers and consequences of genome size variation across organisms are far from understood. We investigated genome size variation and evolution in two major subfamilies of the Neotropical family Bromeliaceae by determining new genome size values for 83 species, testing phylogenetic signal in genome size variation, and assessing the fit to different evolutionary models. For a subset of epiphytic bromeliad species, we also evaluated the relationship of genome size with thermal traits and relative growth rate (RGR), respectively. Genome size variation in Bromelioideae appears to be evolutionary conserved, while genome size among Tillandsioideae varies considerably, not just due to polyploidy but arguably also due to environmental factors. The subfamilies show fundamental differences in genome size and RGR: Bromelioideae have, on average, lower genome sizes than Tillandsioideae and at the same time exhibit higher RGR. We attribute this to different resource use strategies in the subfamilies. Analyses among subfamilies, however, revealed unexpected positive relationships between RGR and genome size, which might be explained by the nutrient regime during cultivation. Future research should test whether there is indeed a trade-off between genome size and growth efficiency as a function of nutrient supply.


Assuntos
Bromeliaceae/genética , Tamanho do Genoma , Genoma de Planta , Filogenia , Poliploidia
2.
New Phytol ; 217(1): 127-139, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28815610

RESUMO

Epiphytic bromeliads represent a major component of Neotropical forests, but the potential effect of climate change on these plants is unclear. We investigated whether and how bromeliads are affected by the predicted 3°C temperature rise by the end of the century. We conducted growth experiments with 17 epiphytic bromeliad species at different temperatures to determine their fundamental thermal niches. By comparing those with niches for germination, we tested whether ontogenetic niche shift or niche contraction occurs in Bromeliaceae. Applying a classical growth analysis, we assessed the relative importance of the underlying growth components on interspecific variations in growth. Members of two bromeliad subfamilies differed in their response to elevated temperatures: Tillandsioideae may be negatively affected, whereas Bromelioideae moved closer to their thermal optimum. Across different ontogenetic stages, thermal niche characteristics revealed both niche shift and niche contraction. Interspecific variation in growth was driven almost exclusively by net assimilation rate at all temperatures. We conclude that the vulnerability of tropical plants to a future increase in temperature may be more variable than suggested by previous studies. We emphasize the importance of assessing niche breadth over multiple life stages and the need for better microclimatic data to link laboratory data with field conditions.


Assuntos
Bromeliaceae/fisiologia , Bromeliaceae/crescimento & desenvolvimento , Mudança Climática , Florestas , Temperatura
3.
Braz. arch. biol. technol ; 61(spe): e18000360, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-974126

RESUMO

ABSTRACT This study presents a system of conversion of mechanical energy produced by physical activity into electric energy obtained by a CC generator coupled to the pedal of an ergometric bicycle. It presents the converter that will be used to adjust the voltage and power coming from the system, as well as the details of the converter design, the simulation and the primary experimental results of the structure. The methodological procedures related to the development of the converter and data acquisition through simulation were carried out based on the bibliographic research. The study is documentary as equipment manuals were used.


Assuntos
Fontes Geradoras de Energia , Esforço Físico , Veículos Off-Road
4.
Ciênc. rural ; 41(9): 1600-1604, set. 2011. ilus, tab
Artigo em Português | LILACS-Express | LILACS | ID: lil-600709

RESUMO

O objetivo deste estudo foi determinar a presença de anticorpos anti-Neospora caninum em amostras coletivas de leite, através da reação de imunofluorescência indireta (RIFI). Para isso, foram coletadas amostras do leite dos tanques refrigerados de 36 rebanhos, das quais foram selecionadas 14 para coletas de amostras individuais de soro sanguíneo e de leite das vacas. Encontrou-se correlação em 12 dos 14 rebanhos selecionados para a amostragem individual dos animais, em comparação à detecção de anticorpos nas amostras coletivas de leite. Foi observada uma concordância de 76 por cento comparando-se o resultado das amostras coletivas com os resultados individuais de leite. Observaram-se baixos títulos de anticorpos (50) no soro sanguíneo dos animais soropositivos, cujos resultados da RIFI no leite coletivo e no sangue foram discordantes. Assim, a partir dos resultados deste estudo, pode-se concluir que a utilização de testes sorológicos para detecção de anticorpos anti-N. caninum em amostras coletivas de leite através da RIFI pode ser uma opção ao diagnóstico para a triagem de rebanhos positivos bem como para estudos epidemiológicos.


The aim of this study was to determine the presence of anti-N. caninum in the bulk milk samples by indirect immunofluorescence assay (IFAT). For this, it was collected samples of milk from refrigerated tanks from 36 herds, of which 14 were selected for sampling of individual blood serum and milk of cows. It was found concordance for 12 of the 14 herds selected for samples of individual animals, compared to the detection of antibodies in the bulk milk samples. Concordance was of 76 percent when comparing the results of the pooled sample with the results of individual milk. It was observed low antibody titers (50) in the serum of animals positive whose results in IFA of bulk milk and blood were discordant. Thus, with the results of this study, it can be concluded that the use of serological tests for detection of anti-N. caninum in the bulk milk samples from the IFAT could be an alternative diagnosis for the screening of positive herds as well as for epidemiological studies.

7.
In. São Paulo. Secretaria Municipal de Saúde. Centro de Controle de Doenças. Subgerência de Doenças e Agravos Não Transmissíveis DANT. Caderno Técnico CAEPS - DANT. São Paulo, s.n, set. 2009. p.23-25.
Não convencional em Português | CidSaúde - Cidades saudáveis | ID: cid-61000
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