Publications by authors named "J Alejandro Valdes"

Low-energy light ion beams are an essential resource in lithography for nanopatterning magnetic materials and interfaces due to their ability to modify the structure and properties of metamaterials. Here we create ferromagnetic/non-ferromagnetic heterostructures with a controlled layer thickness and nanometer-scale precision. For this, hydrogen ion (H) irradiation is used to reduce the antiferromagnetic nickel oxide (NiO) layer into ferromagnetic Ni with lower fluence than in the case of helium ion (He) irradiation.

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Neurodegenerative diseases, including Parkinson's Disease (PD), are a significant global health challenge with no effective therapies to counteract neurodegeneration. Genetic and environmental factors lead to mitochondrial dysfunction and increased reactive oxygen species (ROS), resulting in oxidative stress. This stress reduces levels of Peroxiredoxin 3 (PRDX3), a key protein for maintaining ROS balance at the mitochondrial level, increasing the substantia nigra's susceptibility to damage.

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Investigating microorganisms in metal-enriched environments holds the potential to revolutionize the sustainable recovery of critical metals such as lanthanides (Ln). We observe Hyphomicrobium spp. as part of a Fe/Mn-oxidizing consortia native to the ferruginous bottom waters of a Ln-enriched lake in Czechia.

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In-depth comparative genomic analysis was conducted to predict carbon, nitrogen, and phosphate assimilation pathways in the halotolerant, acidophilic genus Acidihalobacter. The study primarily aimed to understand how the metabolic capabilities of each species can determine their roles and effects on the microbial ecology of their unique saline and acidic environments, as well as in their potential application to saline water bioleaching systems. All four genomes encoded the genes for the complete tricarboxylic acid cycle, including 2-oxoglutarate dehydrogenase, a key enzyme absent in obligate chemolithotrophic acidophiles.

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The Atacama Desert's naturally elevated metal(loid)s pose a unique challenge for assessing the environmental impact of mining, particularly for indigenous communities residing in these areas. This study investigates how copper mining influences the dispersion of these elements in the wind-transportable fraction (<75 μm) of surface sediments across an 80 km radius. We employed a multi-pronged approach, utilizing spatial modeling to map element distributions, exponential decay analysis to quantify concentration decline with distance, regime shift modeling to identify dispersion pattern variations, and pollution assessment to evaluate impact.

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