Publications by authors named "A Parada"

Urea is hypothesized to be an important source of nitrogen and chemical energy to microorganisms in the deep sea; however, direct evidence for urea use below the epipelagic ocean is lacking. Here, we explore urea utilization from 50 to 4000 meters depth in the northeastern Pacific Ocean using metagenomics, nitrification rates, and single-cell stable-isotope-uptake measurements with nanoscale secondary ion mass spectrometry. We find that on average 25% of deep-sea cells assimilated urea-derived N (60% of detectably active cells), and that cell-specific nitrogen-incorporation rates from urea were higher than that from ammonium.

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Concentrations of polycyclic aromatic hydrocarbons were assessed in a sediment core retrieved from Nutrias Lagoon, located within the Rocha Lagoon Protected Area along the SE Uruguayan coast. Using aPb chronology, we reconstructed the historical accumulation of polycyclic aromatic hydrocarbons over the past 123 years (1895-2018). This study, the first of its kind in Uruguay, fills a research gap in understanding historical PAH accumulation and source changes.

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Neuroinflammation is a key component underlying multiple neurological disorders, yet non-invasive and cost-effective assessment of in vivo neuroinflammatory processes in the central nervous system remains challenging. Diffusion weighted magnetic resonance spectroscopy (dMRS) has shown promise in addressing these challenges by measuring diffusivity properties of different neurometabolites, which can reflect cell-specific morphologies. Prior work has demonstrated dMRS utility in capturing microglial reactivity in the context of lipopolysaccharide (LPS) challenges and serious neurological disorders, detected as changes of microglial metabolite diffusivity properties.

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Subterranean rodents of the genus Ctenomys (tuco-tucos) are endemic to South America and have experienced relatively recent radiation. There are about 67 recognized species that originated in approximately 1-2 MY. They stand out for their species richness, extraordinary chromosomal diversity, and wide range of habitat they occupy in the continent.

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Objective: Polyunsaturated fatty acids are categorized as ω-3 or ⍵-6. Previous studies demonstrate that breast cancers display a high expression of fatty acid synthase and high fatty acid levels. Our study sought to determine if changes in plasma or red blood cell membrane fatty acid levels were associated with the response to preoperative (neoadjuvant) chemotherapy in non-metastatic breast cancer patients.

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