Publications by authors named "A Obrador"

A pot experiment was conducted to determine the influence of commercial nanoparticles (ZnO-NPs) at different doses for use as nanofertilizer on nutrient uptake and its distribution in cherry tomato ( L var. cerasiforme) plants in an acidic (soil pH 5.5) and calcareous soil (soil pH 8.

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Obstructive sleep apnea (OSA) is a respiratory condition during sleep caused by repeated pauses in breathing due to upper airway obstruction. It is estimated that OSA affects 30% of the population, but only 10% are well diagnosed due to the absence of a well-defined symptomatology and poor screening tools for early diagnosis. OSA is associated to an endothelial dysfunction inducing several biological responses such as hypoxia, hypercapnia and oxidative stress, among others.

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ZnO nanoparticles (ZnO-NPs) can reach soil in both deliberate and non-deliberate ways, which leads to contamination. Notwithstanding knowledge about ZnO-NPs impacts on earthworms inhabiting these soils is limited and gaps appear in the recovery of damaged functions after their migration to unpolluted environments. To estimate these impacts, earthworms (Eisenia andrei) were exposed to different concentrations of coated ZnO-NPs (20, 250, 500, 1000 mgZnkg) in an acidic agricultural soil (pH 5.

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This study evaluated the influence of ageing of ZnO nanoparticles (NPs) applied to soil on the potential availability and chemical speciation of Zn, and also of their toxicity to aquatic organisms due to transfer of contaminants from soil to water. To this end, soil samples were spiked with two types of bare nanoparticles: b1ZnO NPs (rod- and elongated-shaped) and b2ZnO NPs (near-spherical shaped) and ZnO NPs coated with (3-aminopropyl)triethoxysilane (cZnO NPs) within the 0-800 mg Zn kg soil dose range, and were left to age for 0, 30, 60 and 90 days. The available concentration and speciation of Zn in soil were determined by the DGT (diffusive gradients in thin films) technique and sequential extraction procedures, respectively.

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The increasing use of zinc oxide nanoparticles (ZnO NPs) in agriculture renders it necessary to evaluate their impact on soil non-target organisms. This work studies Zn availability to earthworms from the ZnO (NP and bulk) applied to two agricultural soils with a different pH at 20, 225, 500, and 1000 mg Zn kg. Zn uptakes and the effects on Eisenia andrei, grown under controlled conditions, were determined.

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