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Species relative abundance (SRA) is an essential attribute of biotic communities, which can provide an accurate description of community structure. However, the sampling method used may have a direct influence on SRA quantification, since the use of attractants (e.g., baits, light, and pheromones) can introduce additional sources of variation in trap performance. We tested how sampling aided by baits affect community data and therefore alter derived metrics. We tested our hypothesis on dung beetles using data from flight interception traps (FITs) as a baseline to evaluate baited pitfall trap performance. Our objective was to assess the effect of bait attractiveness on estimates of SRA and assemblage metrics when sampled by pitfall traps baited with human feces.Dung beetles were sampled at three terra firme primary forest sites in the Brazilian Amazon. To achieve our objective, we (i) identified species with variable levels of attraction to pitfall baited with human feces; (ii) assessed differences in SRA; and (iii) assessed the effect of bait on the most commonly used diversity metrics derived from relative abundance (Shannon and Simpson indices). We identified species less and highly attracted to the baits used, because most attracted species showed greater relative abundances within baited pitfall traps samples compared with our baseline. Assemblages sampled by baited pitfall traps tend to show lower diversity

In order to describe radiation induced alterations of renal cell morphology, adult rats were whole-body exposed to 60-cobalt gamma rays at various doses (1, 2, or 4 Gy) and two dose rates (1 Gy/min or 1 Gy/h). 24 h or 48 h after irradiation, kidneys were take off and cortex fragments were fixed and embedded. Paraffin sections were used for light microscope study and TUNEL assay, and epon ones for conventional transmission electron microscope observations. Morphological changes in numerous tubules of irradiated samples were observed mainly in cells of proximal convoluted tubules (PCT) and not in distal ones (DCT), as nuclear and cytoplasm lesions. Epithelial cells containing round and small nucleus with homogenous condensed chromatin were detected in 1 Gy/min samples, which number increased with dose and post-irradiation time. Cells protuberances were seen in PCT lumen and identified as cellular proliferations. Damaged cells appeared TUNEL assay positives when compared to same serial histological cuts. Large tubular necrosis areas were seen only at 4 Gy dose, 1Gy/min dose rate and 48 h post-irradiation time that involved all tubules. Ultrastructural lesions were observed in cortex kidneys 24 h after irradiation at 2 and 4 Gy doses and 1 Gy/min dose rate, displaying all features of apoptotic process mainly in PCT isolated cells. Their appeared with dense cytoplasm that contains clusters of enlarged mitochondrias, numerous light vesicles and condensed heterogeneous chromatin within atypical shape nuclei. Others subcellular alterations of epithelial cells were seen only in 4 Gyirradiated samples as brush border irregular microvilli. Some cellular fragments were detected inside the lumen of intact DCT containing recognizable organelles that we suppose to be apoptotic bodies of injured PCT cells. When compared to controls, glomeruli changes were induced at 1 Gy/h dose rate, 24 h after exposition for the two doses of irradiation as detachment of enlarged podocytes from basal membrane, hypertrophy of mesangial cells, damaged endothelial cells and vacuolization of the parietal leaflet.

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