Publications by authors named "E C Fraga"

Article Synopsis
  • Astyanax bimaculatus, or piabas/lambaris, is a small fish species complex with 18 different species, including some that are hard to distinguish.
  • The study used DNA barcoding to analyze A. bimaculatus populations specifically in Maranhão, comparing genetic diversity to other Brazilian basins and found 32 unique haplotypes.
  • Results showed Maranhão populations are genetically distinct from others, contributing valuable insights into the species' systematics and highlighting significant genetic variation in the region.
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To evaluate the muscle thickness and prevalence of muscle atrophy of the biceps brachii/brachialis (BB) and quadriceps femoris (QF) in critically ill children using ultrasound (US). The prospective longitudinal study was conducted in the pediatric intensive care unit (PICU) of a tertiary hospital in southern Brazil with children and adolescents of both sexes, aged 1 month to 12 years, on invasive mechanical ventilation for 24 h. US measurements were taken up to 24 h after admission, 72 h after, and weekly until discharge from the PICU.

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The present study delved into the world of hidden diversity by examining specimens identified as Leporinus piau from the river basins of the northern Brazilian states of Maranhão and Piauí. Using genetic analyses that combined data from three mitochondrial markers and one nuclear marker, the study identified two well-supported groups, reinforcing the findings of previous publications. The first group, found in samples from the Itapecuru, Mearim, Turiaçu, and Pericumã basins, in Maranhão, appears to represent a relatively ancient diversification and the possibility of concealed cryptic diversity.

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The fish fauna of the Tocantins River possesses many endemic species; however, it is little studied in molecular terms and is quite threatened by the construction of several hydroelectric dams. Therefore, the objective of this study was to identify the ichthyofauna of the Tocantins River using DNA barcoding. For this, collections were carried out in five points of this river, which resulted in the capture of 725 individuals from which partial sequences of the cytochrome oxidase subunit I (COI) gene were obtained for genetic analysis.

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is the most speciose genus of the family Pimelodidae, and is amply distributed in the Neotropical region. The species-level taxonomy and phylogenetic relationships within this genus are still poorly resolved, however. These taxonomic problems and the general lack of data have generated major uncertainties with regard to the identification of specimens from different localities.

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