Mapping density, diversity and species-richness of the Amazon tree flora

Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution

Metallothionein, zinc, and mercury levels in tissues of young rats exposed to zinc and subsequently to mercury

Several studies have described mercury toxicity and the role of metallothioneins (MT) in the detoxification and regulation of metal homeostasis. However, little data exist on this topic during the specific post-natal developmental phase in young mammals. This developmental phase is particularly important since young animals are more sensitive to toxicants than adults. The objective of this work was to investigate whether MT participates in the mechanism of protection conferred by zinc pre-treatment on the toxic effects induced by mercury in neonate rats. Pups were exposed to ZnCl(2) (5 doses of 27 mg/kg/day, s.c.) and subsequently to HgCl(2) (5 doses of 5 mg/kg/day, s.c.); metal (Zn and Hg) and MT contents were analyzed in the liver, kidney, and blood. MT was induced in the liver and kidney of pups of both Zn-sal and Zn-Hg groups, although the greatest increase was in neonates exposed to Zn only. A direct relationship exists between MT and metals for both hepatic and renal tissues, which indicates that the increase in metal levels occurs in parallel to the increase in MT content. Although the heat-treated cytosolic fraction is rich in MT and metals, higher Zn and Hg contents were detected in the insoluble fraction of all tissues. These results suggest that MT is, at least in part, responsible for preventing Hg accumulation in the liver and blood and decreasing renal toxicity.N. C. P. was a recipient of fellowships from CAPES (PDEE)info:eu-repo/semantics/publishedVersio

Production Of Carotenoids From Microalgae Cultivated Using Agroindustrial Wastes

The aim of this work was to evaluate the production of carotenoids from microalgae Phormidium autumnale cultivated using agroindustrial wastes. The carotenoid profile from microalgae biomass was assessed by high performance liquid chromatography coupled with a photodiode array and mass spectrometry detectors. A total of twenty carotenoids were separated from the biomass. The all-trans-β-carotene (70.22 μg/g), all-trans-zeaxanthin (26.25 μg/g), all-trans-lutein (21.92 μg/g), all-trans-echinenone (19.87 μg/g) and cis-echinenone (15.70 μg/g) were the major ones. For the production of single-cell carotenoids it is possible to estimate a total carotenoid production of up to 107,902.5 kg/year in an industrial scale. Based on these results, we observed the potential of P. autumnale to the production of microalgal carotenoid in agroindustrial wastewater. © 2014

Efeito metafilático do zinco injetável sobre parâmetros metabólicos e oxidativos de ovelhas no pós-parto imediato

ABSTRACT The aim of this study was to evaluate a new source of injectable organic zinc (zinc edetate) on the energy and oxidative profile in sheep during the immediate postpartum period. Twenty-six Texel breed animals were previously identified and divided into two experimental groups: the treated group (TG; n= 13) that comprised the animals that received a subcutaneous (SC) injection of 100 mg of zinc edetate (2 mL) fifteen days before the parturition expected date and the control group (CG; n=13) that comprised the animals that received 2mL of physiological solution at the same date of TG. Blood samples were collected on the parturition day for the assessment of serum fructosamine, cholesterol and triglycerides, insulin-like growth factor type 1 (IGF-1), the oxidative stress index (OSi) and blood zinc concentration. In addition to these parameters, the measurement of zinc was made in food given to the animals. There was no difference in metabolic parameters and OSi between the experimental groups (P>0.05), as well as in blood zinc concentrations (P>0.05). The parenteral zinc edentate does not change the energy and oxidative profile of sheep in immediate postpartum