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Understanding the electronic transport properties of low-dimensional devices has increased dramatically in recent decades, especially for those with a promising future for application in nanotechnology. Among these nanoscopic systems are molecular systems, particularly organic molecules such as catechol, representing the small piece of a potential conductor assembled through larger biomolecules and inserted between two or more metal contacts. In this work, we present a theoretical description of the electronic transport of catechol, based on its π -conjugated aromatic system, under an external magnetic field stimulus, which is transverse to the alignment of the molecule. Thus, we analyze catechol's spintronic properties through the magnetoresistance generated by this field. We model the molecule using a tight-binding Hamiltonian and Green's functions; the transmission probability is calculated by means of the Fisher-Lee relation, and the characteristic current–voltage, spin polarization, and magnetoresistance curves based on Landauer's approach for two linking models of catechol to the metallic contacts. The results suggest a strong dependence on the spin direction of the charge carriers and the Zeeman energy (E z) on the Fermi level, generating a switch-like mechanism going from conducting to semiconducting material. This behavior opens a potential application of these catechol-based systems in future spintronic devices. [ABSTRACT FROM AUTHOR]

Jaime Hernández-Ojeda, Luis Miguel Román-Pintos, Adolfo Daniel Rodríguez-Carrízalez, Rogelio Troyo-Sanromán, Ernesto Germán Cardona-Muñoz, María del Pilar Alatorre-Carranza, Alejandra Guillermina Miranda-Díaz Departamento de Fisiología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Jalisco, México Background: Diabetic neuropathy affects 50%–66% of patients with diabetes mellitus. Oxidative stress generates nerve dysfunction by causing segmental demyelinization and axonal degeneration. Antioxidants are considered to be the only etiologic management for diabetic polyneuropathy, and statins such as rosuvastatin increase nitric oxide bioavailability and reduce lipid peroxidation. The aim of this study was to evaluate the antioxidant effect of rosuvastatin in diabetic polyneuropathy. Methods: We conducted a randomized, double-blind, placebo-controlled Phase IIa clinical trial in patients with type 2 diabetes and diabetic polyneuropathy (DPN) stage ≥1b. We allocated subjects to two parallel groups (1:1) that received rosuvastatin 20 mg or placebo for 12 weeks. Primary outcomes were neuropathic symptom score, disability score, and nerve conduction studies, and secondary outcomes were glycemic control, lipid and hepatic profile, lipid peroxidation, and nerve growth factor beta (NGF-β) levels. Results: Both groups were of similar age and duration since diagnosis of diabetes and DPN. We observed improvement of DPN in the rosuvastatin group from stage 2a (88.2%) to stage 1b (41.2%), improvement of neuropathic symptom score from 4.5±2 to 2.4±1.8, and significant (P=0.001) reductions of peroneal nerve conduction velocity (from 40.8±2.2 to 42.1±1.6 seconds) and lipid peroxidation (from 25.4±2 to 12.2±4.0 nmol/mL), with no significant change in glycemic control or β-NGF. Conclusion: The severity, symptoms, and nerve conduction parameters of DPN improved after 12 weeks of treatment with rosuvastatin. These beneficial effects appear to be attributable to reductions in lipid peroxidation and oxidative stress. Keywords: rosuvastatin, diabetic polyneuropathy, nerve conduction, oxidative stress, nerve growth factor beta

We use continuous and survey GNSS data to image the spatial and temporal evolution of afterslip during the 2 months following the Mw 8.3 2015 Illapel earthquake. Our approach solves for the incremental daily slip at the subduction interface using nonnegative least squares with spatial and temporal Laplacian regularization constraints. We find that afterslip developed at three specific areas at the megathrust, surrounding the coseismic rupture. In addition, well resolved afterslip also occurs within the coseismic rupture area that experienced ∼4 m of seismic slip. Our afterslip model shows striking correlations with the spatial distribution of aftershocks and repeating earthquakes. We capture the local afterslip triggered by a Mw 6.8 and two 6.9 aftershocks that ruptured downdip and north of the coseismic rupture, respectively. The latter ones were possibly triggered by the afterslip that developed north of the rupture. We also find a pulse of enhanced aseismic slip lasting a few days south of the rupture that spatially and temporally correlates with a seismicity burst. We finally find that areas of enhanced afterslip spatially correlates with areas having experienced regular seismic swarms observed during the years prior to the Illapel earthquake. This correlation supports the view of localized fluid high pore pressure areas behaving aseismically and surrounding a highly locked asperity, preventing the seismic rupture to propagate into them. Plain Language Summary: After a large earthquake, aseismic slip occurs in the vicinity of the seismic rupture. In this study, we focus on the aseismic slip that occurred after a large subduction earthquake of magnitude 8.3 in 2015 in central Chile. Using GPS time series, we obtain a spatiotemporal view of the aseismic slip during the 2 months following the earthquake. We find that aseismic slip occurred at three preferential areas located at the periphery of the rupture, as observed for many earthquakes. However, we also identify a patch of aseismic slip within the rupture area. We could image the daily afterslip rate and compare it to the daily seismicity and found striking correlations with the spatial distribution of aftershocks. In particular, we find that the largest aftershocks with magnitude 6.8–6.9 are tightly related to the evolution of afterslip. This result suggests that precisely monitoring the evolution of afterslip after a large earthquake might help to define preferential areas of large aftershocks. We also find a potential slow slip event south of the mainshock rupture which correlates with a local increase of seismicity. Finally, we find that the areas of enhanced afterslip had experienced seismic swarms decades before the earthquake, possibly reflecting areas of the fault with high fluid pore pressure. These results highlight new aspects about the dynamics of afterslip. Key Points: A full time‐dependent inversion provides a detailed view of afterslip during the 2.5 months following the Illapel earthquake in ChileAfterslip developed at three preferential areas, one of which overlaps a region of significant coseismic slip (2–4 m)Afterslip shows local and short‐term acceleration after large aftershocks and a slow slip event [ABSTRACT FROM AUTHOR]