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Diversidade de Forcipomyia Meigen 1818 (Ceratopogonidae: Diptera) da Reserva Biológica da Campina, Manaus, Amazonas. s, Amazonas.
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Obtenção e caracterização de bolo chiffon sem glúten e sem derivados de leite com capim santo
No full textMorphology and Chaetotaxy of the Instars of Hydrocanthus sharpi Zimmermann, 1928 (Coleoptera: Noteridae)
No full textThe three instars of Hydrocanthus sharpi Zimmermann, 1928 are described and illustrated, including morphometric and chaetotaxic analyses of the cephalic capsule, head appendages, legs, last abdominal segment, and urogomphus. Larvae of Hydrocanthus Say, 1823 are diagnosed by the following combination of characters: elongate body; posterior tentorial pits not contiguous to occipital foramen; antennomere 4 2-3 times shorter than antennomere 3; non-serrate inner mandibular margin; siphon short, slightly protruding; urogomphi not fused along inner margin. Hydrocanthus differs in chaetotaxy from Suphis Aubé, 1836 by the position of frontoclypeal seta FR10, antennal seta AN3, and maxillary sensilla MX11 and MXj, the presence of several additional setae on the trochanter, the absence of seta MX16 on the maxilla, of seta AB2 on abdominal segment VIII, and of pore MXd on the galea, the length of labial seta LA2 and of urogomphal seta UR4, and the shape of tarsal setae TA3, TA4, TA5, and TA6. © 2019 Coleopterists Society. All rights reserved
Cryptic phenology in plants: Case studies, implications, and recommendations
No full textPlant phenology—the timing of cyclic or recurrent biological events in plants—offers insight into the ecology, evolution, and seasonality of plant-mediated ecosystem processes. Traditionally studied phenologies are readily apparent, such as flowering events, germination timing, and season-initiating budbreak. However, a broad range of phenologies that are fundamental to the ecology and evolution of plants, and to global biogeochemical cycles and climate change predictions, have been neglected because they are “cryptic”—that is, hidden from view (e.g., root production) or difficult to distinguish and interpret based on common measurements at typical scales of examination (e.g., leaf turnover in evergreen forests). We illustrate how capturing cryptic phenology can advance scientific understanding with two case studies: wood phenology in a deciduous forest of the northeastern USA and leaf phenology in tropical evergreen forests of Amazonia. Drawing on these case studies and other literature, we argue that conceptualizing and characterizing cryptic plant phenology is needed for understanding and accurate prediction at many scales from organisms to ecosystems. We recommend avenues of empirical and modeling research to accelerate discovery of cryptic phenological patterns, to understand their causes and consequences, and to represent these processes in terrestrial biosphere models. © 2019 John Wiley & Sons Lt
Estudo hidrológico do efeito de barramento hidráulico no Rio Tarumã-Açu, Manaus-AM
Get PDFAmazonian rivers play a strategic role in the development of the region. Studying them allows guidance in decision-making, regarding the management of the conflicting uses of the resources of a watershed. However, there is still a great lack of hydrological data on them, especially in small basins. A river may have its attributes changed by another through the physical characteristics of the confluence and by the backwater effect. This is the case of a tributary of the Negro river, the Tarumã-Açu river, the largest river in the urban area of Manaus, Amazonas — Brazil. The objective of this study was to analyze how the backwater effect and the morphological characteristics of the confluence interact with the physical parameters of the Tarumã-Açu river. Four data collections were performed between 2018 and 2019 using the 600 kHz Acoustic Doppler Current Profile (ADCP), in five cross sections on the Tarumã-Açu river and the Negro river, before and after the river’s mouth, collecting discharge, flow velocity and direction, depth, width, surface temperature and backscatter data. Due to the absence of knowing water level measurements on the Tarumã-Açu river, the mean depth was added to the bed elevation to obtain the water level. The bed level was obtained through a bathymetric survey with ADCP, georeferenced at sea level by the Precision Point Positioning method. The hydraulic model HEC-RAS was used to estimate the behavior of the backwater effect of the Negro river on the water level of the Tarumã-Açu river. The flow has been considered as one-dimensional, permanent and subcritical. The results shows very dispersed discharge, highly influenced by the speed and depth of the section. It was observed through the velocity of the flow, surface temperature and backscatter that the entrance of the Negro River by the surface of the Tarumã-Açu river over a reach of 17 km upstream of its mouth, which causes alteration in its physicochemical characteristics. Tests with HEC-RAS indicate that Tarumã-Açu river assumes the same level of the Negro river when it reaches the quota of 19 meters (sea level), regardless of the upstream flow, which occurs during five months of the year, on average. The disagreement beds between the channels, the confluence angle and the momentum flow ratio between the rivers are the possible causes of the constant influence of the Negro river on the Tarumã-Açu river.Rios amazônicos desempenham função estratégia no desenvolvimento da região. Estuda-los permite orientar na tomada de decisão em relação ao gerenciamento dos usos conflitosos dos recursos de uma bacia hidrográfica. No entanto, ainda é grande a falta de dados hidrológicos sobre eles, sobretudo em pequenas bacias. Um rio pode ter seus atributos alterados por outro através das características físicas de sua confluência e pelo fenômeno do barramento hidráulico. Esse é o caso de um afluente do rio Negro, o rio Tarumã-Açu, maior rio da zona urbana de Manaus, Amazonas – Brasil. O objetivo deste estudo foi analisar como o efeito de barramento hidráulico e as características morfológicas da confluência interagem com os parâmetros físicos do rio Tarumã-Açu. Para isso, foram realizadas quatro coletas de dados entre os anos de 2018 e 2019 utilizando o Perfilador Acústico de Corrente por Efeito Doppler (ADCP) de 600 kHz, em cinco seções transversais no rio Tarumã-Açu e no rio Negro, antes e após a foz do Tarumã-Açu, realizando medidas de vazão, velocidade e direção do fluxo, profundidade, largura, temperatura superficial e retorno do eco retroespalhado pelo equipamento (backscatter). Devido à ausência de medição de cota no rio Tarumã-Açu, somou-se a profundidade média com a elevação do leito para se obter o nível da água. O nível do leito, por sua vez, foi obtida através de levantamento batimétrico com o ADCP, georreferenciada ao nível do mar pelo método de Posicionamento por Ponto Preciso. O modelo hidráulico HEC-RAS foi empregado para estimar o comportamento do efeito de barramento hidráulico do rio Negro sobre o nível da água do rio Tarumã-Açu. Os testes foram realizados tomando o escoamento como unidimensional, permanente e subcrítico. Os resultados mostram vazões bastante dispersas, altamente influenciadas pela velocidade e profundidade da seção. Observou-se por meio da velocidade do fluxo, da temperatura superficial e do backscatter, que a entrada do rio Negro pela superfície do rio Tarumã-Açu sobre um trecho de 17 km a montante de sua foz, o que causa alteração nas características físico-químicas de suas águas. Testes com HEC-RAS apontam que o Tarumã-Açu assume o mesmo nível do rio Negro quando este atinge a cota de 19 metros (nível do mar), independente da vazão a montante, o que ocorre durante cinco meses do ano em média. A discordância entre os leitos dos canais, o ângulo da confluência e a razão de fluxo de momentum entre os rios são as possíveis causas da influência constante do rio Negro sobre o rio Tarumã-Açu
Chemical composition and larvicidal activity of the essential oil from the leaves of <i>Onychopetalum periquino</i> (Rusby) D.M. Johnson & N.A. Murray
No full textEffects of Phenanthrene on the Amazonian fish tambaqui Colossoma macropomum: LC50, growth and hematology
Get PDFA further study on Franciscobasis Machado & Bedê, 2016 (Odonata: Coenagrionidae), a newly described genus from Minas Gerais, Brazil
Get PDFThe genus Franciscobasis Machado & Bedê, 2016 is endemic to the Serra da Canastra National Park in Minas Gerais state, Brazil. Two species of Franciscobasis were described simultaneously with the genus description: F. franciscoi and F. sonia, the latter described only from females. Through morphological and molecular analysis, we investigated if F. sonia may represent the young female of F. franciscoi. Resulting data did not present adequate differences between females to characterize them as different species. Therefore, we suggest that F. sonia is a junior synonym of F. franciscoi, and the female of F. franciscoi goes through a complex ontogenetic color change. © 2019 Vilela et al
Evaluation of antiparasitary, cytotoxic and antioxidant activity and chemical analysis of Tarenaya spinosa (Jacq.) Raf. (Cleomaceae)
No full textActive principles found in plants may aid in antiparasitic treatments, however it is important to evaluate if they do not have cytotoxicity. The leishmanicidal and trypanocidal activities of Tarenaya spinosa were evaluated, as well as the cytotoxic potential of their extracts, as well as the phytochemical and antioxidant profile. The phytochemical profile was described by Nuclear Magnetic Resonance of Hydrogen (1H-NMR) and High Performance Liquid Chromatography (HPLC-DAD). The antiparasitic activity was performed with the promastigote forms of Leishmania spp. and epimastigotes from Trypanosoma cruzi. Cytotoxicity was assessed using NCTC mammalian clone 929 fibroblasts. The antioxidant potential was assessed with the DPPH free radical. The ethanolic extract (EETS) and aqueous (EATS) presented terpenes, steroids, nitrogen compounds, sugars, phenolic compounds (simple phenylpropanoides and coumarins), flavonoids and chacolnas. The polyphenolic profile showed that caffeic acid was the major compound of both extracts. It was observed that the EETS showed a significant antileishmania activity against L. brasiliensis (LC50 81.75 μg/mL) and L. infantum (LC50 141.6 μg/mL), whereas EATS had low antileishmania activity. Against T. cruzi, the extracts presented LC50 > 1000 μg/mL. The extracts of T. spinosa present high antioxidant activity, with EETS having an IC50 of 377.7 μg/mL and EATS IC50 of 445.8 μg/mL. However, EETS was toxic to fibroblasts with an LC50 of 397.9 μg/mL, whereas no cytotoxicity was observed for EATS. Therefore, EATS is a promising source of antioxidant compounds since it does not present cytotoxicity. © 2019 South African Association of Botanist