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Item type:Item, Estrutura vertical e relações de similaridade da velocidade do vento na subcamada rugosa sobre coberturas de vegetação densa(2025) Gomes, Leandro dos Reis Biase; Dias Júnior, Cléo Quaresma; Santana, Raoni Aquino Silva deThe roughness sublayer (RSL) is a region within the surface boundary layer (SBL) where the turbulence behavior differs from predictions made by the Monin-Obukhov similarity theory (MOST), located near or within surface roughness elements, such as trees, buildings and other obstacles. Most measurements performed in forested areas, such as the Amazon rainforest, occur within the RSL, but there is still no widely accepted theory to describe its behavior, and its basic characteristics are poorly understood. This study aims to estimate the RSL height (z∗ ) using three methodologies existing in the literature De Bruin and Moore (1985), Verhoef (1997) and Kuparinen (2007) and to propose a new formulation based on dimensionless profiles more compatible with turbulent flow over the Amazon rainforest canopy. The scales considered in this analysis include the wind shear length scale (Ls ), the height of the inflection point in the vertical wind profile (zi ), and the wind speed at that point (ui ), obtained from data obtained from sonic anemometers installed on the towers of the ATTO (Amazon Tall Tower Observatory) project. In the method of De Bruin and Moore, the mean height of the RSL was 56 m, in that of Verhoef (1997) 55 m, and in that of Kuparinen it was 64 m. From the organization of the Ls, zi and ui scales, the relationship z∗ = zi + 2Ls was proposed, resulting in an average RSL height of 87 m, a more realistic value, considering the assumption that the RSL height is between 2 and 3h (with h = 35 m being the canopy height in ATTO), as advocated by several authors. In addition to allowing the calculation of the RSL height, such scales can be used as normalization factors for physical quantities such as length and velocity scales. It was observed that the turbulent profiles normalized by Ls, zi and ui presented statistical errors (correlation and standard error, for example) considerably smaller than the profiles normalized by classical parameters such as friction velocity (u∗ ) and h, which can contribute to obtaining more realistic parameterizations of the turbulent exchange processes within and above the Amazon forest canopy.Item type:Item, Boletín de monitoreo climático de las principales cuencas hidrográficas, Volume 3, Numero 37(2025-09-10) Senna, Renato Cruz; Carvalho, Luan Rogério Rodrigues; Arcos, Adriano Nobre; Rocha, Tainá Sampaio Xavier ConchyItem type:Item, Boletim de Monitoramento Climático de Grandes Bacias, Volume 5, Número 37(2025-09-10) Senna, Renato Cruz; Carvalho, Luan Rogério Rodrigues; Arcos, Adriano Nobre; Rocha, Tainá Sampaio Xavier ConchyItem type:Item, Climate monitoring bulletin for the major river basins, Volume 3, Number 37(2025-09-10) Senna, Renato Cruz; Carvalho, Luan Rogério Rodrigues; Arcos, Adriano Nobre; Rocha, Tainá Sampaio Xavier ConchyItem type:Item, Avaliação do efeito tóxico e genotóxico do óleo essencial de Piper marginatum (Jacq.) ao controle de Aedes aegypti, na Amazônia central(2025) Matos, Evely Lima; Rafael, Míriam Silva; Cruz, Daniel Luís VianaAedes aegypti, an important vector of arboviruses responsible for dengue, Zika, and chikungunya, has shown resistance to synthetic chemical insecticides, which has driven the search for effective vector control alternatives that are less harmful to the environment and to non-target organisms. Among the promising options, the use of essential oils (EOs) from plants of the Piperaceae family, especially from the Piper genus, stands out. In this context, the present study investigated the toxic and genotoxic effects of the essential oil of Piper marginatum (EOPM) on Ae. aegypti larvae and isogenic BALB/c strain mice (Mus musculus), aiming to evaluate its potential as an alternative for vector control. The EOPM was extracted by hydrodistillation, and its composition was determined by Gas Chromatography coupled to Mass Spectrometry (GC-MS), identifying 49 compounds, mainly sesquiterpenes and monoterpenes. The larvicidal bioassay on Ae. aegypti demonstrated larval mortality at all tested concentrations (50 to 90 µg/mL), with a progressive increase in mortality with rising concentration and exposure time. The Lethal Concentrations (LC10, LC50, and LC90) determined after 72 hours were 44.49, 66.61, and 88.73 µg/mL, respectively. In the genotoxicity bioassay, conducted with larvae exposed to concentrations of 15, 25, and 35 µg/mL, neuroblastic cells were analyzed, and genotoxic damage was observed, including micronuclei, in generations 1 and 2 (G1 and G2), with significant differences (p < 0.001) compared to the controls, especially the negative control (NC), although differences were also noted relative to the positive control (PC). In BALB/c mice, the acute oral toxicity test revealed no adverse effects at doses up to 2000 mg/kg/day, classifying EOPM as safe (Category C, according to OECD). In the micronucleus test, EOPM did not cause a significant increase in micronuclei in bone marrow, whereas the mutagenic agent methyl methanesulfonate (MMS), used as the PC, showed strong mutagenic activity. Cytotoxicity was dose-dependent after 24 hours, with a reduction in the frequency of polychromatic erythrocytes (PCEs) and in the polychromatic to normochromatic erythrocyte (PCE:NCE) ratio, an effect that was not maintained after 48 hours. These results indicate that EOPM exhibits larvicidal and genotoxic activity against Ae. aegypti without evidence of acute oral toxicity or mutagenicity in mammals under the tested conditions. Thus, EOPM may represent an effective and viable alternative for Ae. aegypti population control and, potentially, a safer approach from an environmental perspective for the development of bioinsecticides targeting epidemiologically relevant vectors. Further studies are needed to confirm its safety in other non-target organisms.