6 research outputs found
Water oxidation with mononuclear ru complexes. Below the tip of the iceberg: the oxo-bridge scenario
La conversión de la energía solar en combustibles limpios como el H2 o el MeOH representa uno de los candidatos más prometedores para la sustitución de fuentes de energía basadas en combustibles fósiles. Las celdas solares electroquímicas requieren un catalizador en el ánodo que lleve a cabo eficazmente la oxidación de agua a oxígeno. El trabajo de tesis presentado consiste en un estudio detallado de catalizadores mononucleares de Ru que desempeñan dicha labor y un análisis exhaustivo de las rutas moleculares implicadas en el proceso. Nuestros resultados demuestran que existe un conjunto de complejos con ligandos puente oxo y pasos de reacción que han sido inadvertidos hasta la fecha, más allá del mecanismo propuesto actualmente aceptado.Cabe destacar que la oxidación de los complejos mononucleares produce su paulatina transformación en complejos dinucleares, que funcionan como catalizadores robustos para la oxidación del agua.Conversion of solar energy into clean fuels like H2 or MeOH represents one of the most promissory candidates in order to replace carbon-based energy resources. The development of a commercially available photoelectrochemical cell for water splitting requires an efficient catalyst on the anode to carry out the oxidation of water to dioxygen. This thesis focuses in the study of mononuclear Ru water oxidation catalysts with a special emphasis in the molecular pathways occurring during the catalytic process. We have achieved strong evidences showing that the current accepted mechanistic proposal is incomplete, thus the oxidation of mononuclear complexes produces a large set of strongly correlated oxo bridge Ru complexes that have remained unnoticed until now. It is worth noting the gradual formation of rugged oxo bridge dinuclearRu water oxidation catalysts from the oxidation of the initial mononuclear complexes
Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)
Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters.
Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs).
Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001).
Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio
Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo
Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level
Análisis de factores relacionados en la implementación de seguros de transporte en DF Zarajusey
Seminario: El crédito comercial y su importancia en los negocios internacionale
Retinal Nerve Fiber Layer in Patients with Alcohol Use Disorder
(This article belongs to the Special Issue Optics and the Brain)The objectives of the present study are to determine the effects of alcohol use on the retinal nerve fiber layer (RNFL) thickness and macular thickness of abstinent patients with alcohol use disorders (AUD) and to assess whether it correlates with alcohol consumption and/or cognitive impairment. This was a prospective, observational study that included 21 patients (42 eyes) and 21 controls (42 eyes). Patients met the criteria for early remission AUD at the moment of inclusion. We used optical coherence tomography to assess retinal thickness. Macular thickness in the group of AUD patients was lower in all quadrants (p < 0.05), with the exception of the peripheral and central. Regarding the nerve fiber layer in the macular and papilla areas, we found no significant differences. At the retina ganglion cell layer and in the nerve fiber of the macula, we found significant differences in all quadrants (p < 0.05), with the exception of the superior and superior nasal area, for the right eye. For the left eye, the only differences were found in the lower quadrant. Finally, when comparing the AUD patients to the controls, we found significant reductions in the ganglion cell layer of the macula in all quadrants in the former. There was a significant correlation between these findings and cognitive impairment (measured with the Test de Detección de Deterioro Cognitivo en Alcoholismo (TEDCA)), but not with alcohol consumption. Alcohol consumption is correlated with retinal harm and related cognitive decline.Universidad Camilo José Cela (España)Centro Óptico MonteroDepto. de Optometría y VisiónFac. de Óptica y OptometríaTRUEpu