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241.
Izaias M. Fernandes Luzia S. Lourenço Rafaela P. Ota Milena M. M. Moreira Cláudio H. Zawadzki 《Environmental Biology of Fishes》2013,96(7):837-848
The aim of this study was to evaluate the effects of local, regional and temporal factors structuring fish assemblages in Meridional Amazonian streams during the months of May (rainy season) and August (dry season) of 2008. To accomplish this task, 14 streams located in Serra do Expedito (Aripuanã River basin) were sampled along 30-m stretches. A total of 3,212 specimens distributed among five orders, 18 families, and 55 species were recorded. The fish assemblage structure in the streams presented variation among types of riparian vegetation (local factor) and watersheds (regional factor), but did not present variation between seasons (temporal factor) and stream order (regional factor). Larger streams with margins covered with pasture presented higher species richness and abundance than smaller streams with margins covered with forest. 相似文献
242.
Cleide Carnicer Luciano B. Lima Fernando Mayer Pelicice Dilermando Pereira Lima-Junior 《Journal of fish biology》2023,102(1):83-95
Syntheses of knowledge are important to reveal trends, biases and gaps in the scientific literature, indicating main data shortfalls and research needs. In this regard, the authors conducted a broad systematic review on the literature about freshwater fish eggs and larvae to investigate (a) temporal trends in the global scientific production, (b) the scope and habitat types, (c) the spatial distribution of studies, (d) the fish species contemplated and their respective conservation status and (e) the factors associated with the spatial distribution of studies. They analysed 654 studies published between 1950 and 2020. The number of studies has increased over time, but with a weak trend. Most studies investigated basic questions about biology and ecology and were carried out chiefly in rivers and lakes. These studies covered 95 freshwater ecoregions (22.3% of all ecoregions) and recorded 871 fish species (4.8% of all freshwater fish currently described). Most species were assessed by the IUCN and classified into six threat categories, but approximately 35% were not evaluated. The main drivers affecting the spatial distribution of studies were ecoregion area, road density, river volume and the number of hydroelectric plants. Results point to significant biases and gaps in the global scientific literature on fish eggs and larvae, especially associated with habitat type, spatial distribution and target species, emphasizing the need to address specific topics. Such biases and gaps indicate the existence of important data shortfalls, which compromise management and conservation planning, as information on fish eggs and larvae is basic and critical for the assessment of fish recruitment and population dynamics. 相似文献
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Cellulase and β-D-glucosidase activity have been identified in Venturia inaequalis, the causal agent of apple scab. Most of the activity of the enzymes was associated with the mycelium after homogenization. The activities were relatively weak in vitro compared to those of other plant pathogens. With a new screening technique, β-D-glucosidase hyperproducing mutants were obtained. 相似文献
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Milson S. Barbosa Cintia C. C. Freire Ranyere L. Souza Rebeca Y. Cabrera-Padilla Matheus M. Pereira Mara G. Freire Álvaro S. Lima Cleide M. F. Soares 《Biotechnology progress》2019,35(4):e2816
In this work, the effect of several phosphonium-based ionic liquids (ILs) on the activity of lipase from Burkholderia cepacia (BCL) was evaluated by experimental assays and molecular docking. ILs comprising different cations ([P4444]+, [P444(14)]+, [P666(14)]+) and anions (Cl−, Br−, [Deca]−, [Phosp]−, [NTf2]−) were investigated to appraise the individual roles of IL ions on the BCL activity. From the activity assays, it was found that an increase in the cation alkyl chain length leads to a decrease on the BCL enzymatic activity. ILs with the anions [Phosp]− and [NTf2]− increase the BCL activity, while the remaining [P666(14)]-based ILs with the Cl−, Br−, and [Deca]− anions display a negative effect on the BCL activity. The highest activity of BCL was identified with the IL [P666(14)][NTf2] (increase in the enzymatic activity of BCL by 61% at 0.055 mol·L−1). According to the interactions determined by molecular docking, IL cations preferentially interact with the Leu17 residue (amino acid present in the BCL oxyanion hole). The anion [Deca]− has a higher binding affinity compared to Cl− and Br−, and mainly interacts by hydrogen-bonding with Ser87, an amino acid residue which constitutes the catalytic triad of BCL. The anions [Phosp]− and [NTf2]− have high binding energies (−6.2 and −5.6 kcal·mol−1, respectively) with BCL, and preferentially interact with the side chain amino acids of the enzyme and not with residues of the active site. Furthermore, FTIR analysis of the protein secondary structure show that ILs that lead to a decrease on the α-helix content result in a higher BCL activity, which may be derived from an easier access of the substrate to the BCL active site. 相似文献
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Reis Regiane Mônica dos Luzia da Silva Lourenço Jerry Penha Izaias Médice Fernandes 《Zeitschrift fur angewandte Ichthyologie》2020,36(4):533-535
The length–weight relationships (LWRs) were estimated of seven fish species from 22 localities in the Pantanal wetland between Mach 2006 and April 2011. Fish were sampled using seven gill nets (20 × 1.5 m; mesh size: 12, 15, 18, 20, 25, 30 and 50 mm between opposing knots) and throw traps (made of 1 m3 metal cubes, covered by a 1.5 mm nylon mesh). Standard length and weight were measured and used to calculate the LWR parameters. Values for parameter b varied from 2.87 (Apistogramma borellii) to 3.29 (Hoplerythrinus unitaeniatus) and, such values are within the expected range. 相似文献
250.
Daniela Camargos Costa Vanessa Pecini da Cunha Gabriela Maria Pereira de Assis Júlio César de Souza Junior Zelinda Maria Braga Hirano Mércia Eliane de Arruda Flora Satiko Kano Luzia Helena Carvalho Cristiana Ferreira Alves de Brito 《Memórias do Instituto Oswaldo Cruz》2014,109(5):641-643
Blood infection by the simian parasite, Plasmodium simium, was
identified in captive (n = 45, 4.4%) and in wild Alouatta clamitans
monkeys (n = 20, 35%) from the Atlantic Forest of southern Brazil. A single malaria
infection was symptomatic and the monkey presented clinical and haematological
alterations. A high frequency of Plasmodium vivax-specific
antibodies was detected among these monkeys, with 87% of the monkeys testing positive
against P. vivax antigens. These findings highlight the possibility
of malaria as a zoonosis in the remaining Atlantic Forest and its impact on the
epidemiology of the disease. 相似文献