Carbon nanofiber-supported tantalum oxides as durable catalyst for the oxygen evolution reaction in alkaline media

Active and durable electrocatalysts for the oxygen evolution reaction (OER), capable of replacing noble metal catalysts, are required to develop efficient and competitive devices within the frame of the water electrolysis technology for hydrogen production. In this work, we have investigated tantalum based catalysts supported on carbon nanofibers (CNF) for the first time. The effect of CNF characteristics and the catalyst annealing temperature on the electrochemical response for the OER have been analyzed in alkaline environment using a rotating ring disc electrode (RRDE). The best OER activity and oxygen efficiency were found with a highly graphitic CNF, despite its lower surface area, synthesized at 700 °C, and upon a catalyst annealing temperature of 800 °C. The ordering degree of carbon nanofibers favors the production of oxygen in combination with a low oxygen content in tantalum oxides. The most active catalyst exhibited also an excellent durability.The authors want to thank the Ministerio de Economía, Industria y Competitividad (MICINN) and FEDER for the received funding in the project of reference ENE2017-83976-C2-1-R, and to the Gobierno de Aragón (DGA) for the funding to Grupo de Investigación Conversión de Combustibles ( T06_17R ). J.C. Ruiz-Cornejo acknowledges DGA for his PhD grant. D. Sebastián acknowledges the MICINN for the Ramón y Cajal research contract (RyC-2016-20944

The influence of adherence to the Mediterranean diet on academic performance is mediated by sleep quality in adolescents

Aim: This study examined the association of adherence to the Mediterranean diet with academic performance and tested whether this association was mediated by sleep in Spanish adolescents. Methods: We recruited 269 adolescents (52% boys) aged 13.9 ± 0.3 years from the Deporte, ADOlescencia y Salud study of 38 secondary schools and sport clubs in Castellon, Spain, between February and May 2015. Adherence to the Mediterranean diet was assessed by the KIDMED questionnaire, sleep quality was evaluated with the Pittsburgh Sleep Quality Index test and sleep duration was objectively computed using a wrist-worn accelerometer. Academic performance was assessed through final school grades and a validated test. Results: Greater adherence to the Mediterranean diet was associated with higher scores in language, core subjects, grade point average and verbal ability (p < 0.05). Sleep quality acted as a significant mediator of the association between adherence to the Mediterranean diet and final grades in maths, language, core subjects and the grade point average. Conclusion: Our data show that the influence of adherence to the Mediterranean diet on academic performance was mediated by sleep quality in adolescents. Education and public health professionals should work together to achieve both improved health status and academic performance in adolescents

Medicina humana espacial: Performance fisiológico y contramedidas para mejorar la salud del astronauta: Human space medicine: Physiological performance and countermeasures to improve the astronaut's health

This Review Article is presented based on current scientific evidence on space medicine focused on human physiology and its countermeasures. Therefore, a non-systematic bibliographic search of scientific articles and research books in English-Spanish of the last 7 years was carried out, detailing their application in humans, murine models and in vitro experiments. The conditions of the space environment such as microgravity and radiation that produce considerable physiological changes in the cardiovascular system (redistribution of fluids, cardiovascular remodeling, arrhythmias) were taken into account; nervous (sensorimotor, neurosensory, neurovestibular); respiratory (volume and capacity changes); renal (lithiasis); musculoskeletal (muscular atrophy, osteoporosis); hematological (anemia); immunological (immune dysregulation) and digestive (intestinal microbiota disorder). In addition, there are biological, molecular and genetic processes still to be explored, in order to know and mitigate the uncertain mechanisms triggered in extreme and dangerous environments. Therefore, it is a priority to develop and implement countermeasures to reduce the harmful effects on health, with the aim of guaranteeing the astronaut's adaptation, safety and performance during future space flights.Se presenta este Artículo de Revisión con base en la evidencia científica actual sobre medicina espacial enfocada en fisiología humana y sus contramedidas. Por lo cual se realizó una búsqueda bibliográfica no sistemática de artículos científicos y libros de investigación en inglés-español de los últimos 7 años, que detallan su aplicación en seres humanos, modelos murinos y experimentos in vitro. Se tomaron en cuenta las condiciones del ambiente espacial como microgravedad y radiación que producen considerables cambios fisiológicos en el sistema cardiovascular (redistribución de líquidos, remodelación cardiovascular, arritmias); nervioso (sensitivomotores, neurosensoriales, neurovestibulares); respiratorio (cambios de volúmenes y capacidades); renal (litiasis); musculo-esquelético (atrofia muscular, osteoporosis); hematológico (anemia); inmunológico (desregulación inmune) y digestivo (alteración de la microbiota intestinal). Además, existen procesos biológicos, moleculares y genéticos aún por explorar, para conocer y mitigar los mecanismos inciertos desencadenados en ambientes extremos y peligrosos. Por lo tanto, es una prioridad desarrollar e implementar contramedidas para reducir los efectos nocivos en la salud, con el objetivo de garantizar la adaptación, seguridad y performance del astronauta durante futuros viajes espaciales

Precision Electron-Beam Polarimetry using Compton Scattering at 1 GeV

We report on the highest precision yet achieved in the measurement of the polarization of a low energy, $\mathcal{O}$(1 GeV), electron beam, accomplished using a new polarimeter based on electron-photon scattering, in Hall~C at Jefferson Lab. A number of technical innovations were necessary, including a novel method for precise control of the laser polarization in a cavity and a novel diamond micro-strip detector which was able to capture most of the spectrum of scattered electrons. The data analysis technique exploited track finding, the high granularity of the detector and its large acceptance. The polarization of the $180~\mu$A, $1.16$~GeV electron beam was measured with a statistical precision of $<$~1\% per hour and a systematic uncertainty of 0.59\%. This exceeds the level of precision required by the \qweak experiment, a measurement of the vector weak charge of the proton. Proposed future low-energy experiments require polarization uncertainty $<$~0.4\%, and this result represents an important demonstration of that possibility. This measurement is also the first use of diamond detectors for particle tracking in an experiment.Comment: 9 pages, 7 figures, published in PR

SEROPREVALENCIA DE Neospora caninum EN PERROS DE ESTABLOS LECHEROS DE LA CUENCA IZQUIERDA DEL VALLE DEL MANTARO

La neosporosis es una enfermedad emergente, considerada causa importante de aborto en el ganado bovino y de procesos neuromusculares graves en perros. El objetivo del presente estudio fue determinar la seroprevalencia de Neospora caninum en perros de establos lecheros de la cuenca izquierda del valle del Mantaro. Se evaluaron 124 sueros de perros, provenientes de 24 establos lecheros de las provincias de Huancayo, Jauja y Concepción. Se halló una prevalencia de anticuerpos contra N. caninum de 19.4 ± 7.0% (24/124), en una dilución de 1:50, mediante la prueba de inmunofluorescencia indirecta. El porcentaje de establos que poseían al menos un perro infectado fue de 62.5% (15/24). No se halló asociación entre la tasa de infección y las variables ubicación geográfica (provincia), edad, sexo y procedencia (en el establo o en los alrededores). Estos resultados demuestran que los caninos del valle del Mantaro presentan una prevalencia moderada de infección con N. caninum; y considerando que dicha infección está presente en la mayoría de los establos de la zona, se recomienda el control del acceso de los canes a los establecimientos lecheros en el valle del Mantaro.The neosporosis is an emergent disease, and considered as an important cause of abortion in cattle and a cause of neuromuscular disorders in dogs. The aim of the present study was to determine the seroprevalence of Neospora caninum in dogs of dairy farms in the left zone of the valley of Mantaro. A total of 24 serum samples of dogs living in and in the vicinity of 24 dairy farms of the provinces of Huancayo, Jauja and Concepcion were evaluated. The seroprevalence of antibodies against N. caninum was 19.4 ± 7.0% (24/124) in a dilution of 1:50, using the indirect immunofluorescense test. The percentage of farms having at least one infected dog was 62.5% (15/24). Statistical relationships between the rate of infection and the geographical location (province), age, sex, and origin (in and closeby the farm) did not exist. These results showed that dogs in the valley of Mantaro presented a moderate seroprevalence of N. caninum; and considering that the infection is present in most dairy farms of the valley, is recommended to limit the access of dogs to dairy farms in the valley

Actividad antiinflamatoria del extracto etanólico de las hojas de Manihot esculenta Crantz (yuca) en un modelo experimental de inflamación aguda: Anti-inflammatory activity of the ethnolic extract of the leaves of manihot esculenta Crantz (yuca) in an experimental model of acute inflammation

Introduction: Manihot esculenta Crantz (yucca) leaves have been used around the world and over time in order to decrease the anti-inflammatory response. Objective: To evaluate the anti-inflammatory activity of the ethanolic extract of the Manihot esculenta Crantz leaf in rats. Methods: An experimental study was conducted. The study population included 60 albino rats sp. Rattus novergicus, distributed in 4 groups of 15 rats each. A homogeneous solution of ethanolic extract of Manihot esculenta Crantz leaves was used for intraperitoneal administration. Carrageenan was used as an inflammatory inducer that was administered intradermally; for the measurement of plantar edema, the Digital Water Plethysmometer (LE7500) was used. Tween 80 / water solution (1:10) was administered to the negative control group at a dose of 1mL./100g., To the betamethasone positive control group 4mg / Kg and to treatment groups 1 and 2 Manihot esculenta Crantz, 2 mg / kg and 4 mg / kg, respectively. The 1-tail ANOVA test and the Tukey post hoc test were used for comparisons between the groups. Results: In 37.67% of treatment group 2 a reduction in edema was observed 3 hours after administering Manihot esculenta Crantz (p &lt;0.05). In both administration groups of Manihot esculenta Crantz there was a nonsignificant trend to reduce plantar edema with values close to significance. Conclusion: The Manihot esculenta Crantz ethanolic extract at a 4 mg / kg dose probably have anti-inflammatory activity in this animal model of acute inflamation.Introducción: Las hojas de Manihot esculenta Crantz (yuca) han sido usadas alrededor del mundo y a lo largo del tiempo con el fin de disminuir la respuesta antiinflamatoria. Objetivo: Evaluar la actividad antiinflamatoria del extracto etanólico de la hoja de Manihot esculenta crantz en ratas. Métodos: Se realizó un estudio tipo experimental. La población de estudio fueron 60 ratas albinas sp. Rattus novergicus, distribuidas en 4 grupos de 15 ratas cada uno. Se usó una solución homogénea de extracto etanólico de hojas de Manihot esculenta crantz para su administración vía intraperitoneal. Se utilizó carragenina como inductor inflamatorio, que fue administrado por vía intradérmica; para la medición del edema plantar, se hizo uso del Digital Water Plethysmometer (LE7500). Se administró al grupo control negativo solución de tween 80/agua (1:10) a dosis de 1ml/10g., al grupo control positivo betametasona 4mg/Kg y a los grupos de tratamiento 1 y 2 Manihot esculenta crantz, 2 mg/kg y 4 mg/kg, respectivamente. Se utilizó la prueba de ANOVA de 1 cola y la prueba post-hoc de Tukey, para las comparaciones entre los grupos. Resultados: En el 37,67% del grupo de tratamiento 2 se observó una reducción del edema a las 3 horas de administrar Manihot esculenta crantz (p &lt;0,05). En otras mediciones se encontró una tendencia no significativa en ambos grupos de administración de Manihot esculenta crantz a la reducción del edema plantar. Conclusión: El extracto etanólico de Manihot sculenta a partir de la dosis de 4 mg/kg parece tener actividad antiinflamatoria en la reducción del edema plantar en el modelo animal utilizado

IAOx induces the SUR phenotype and differential signalling from IAA under different types of nitrogen nutrition in Medicago truncatula roots

Indole-3-acetaldoxime (IAOx) is a particularly relevant molecule as an intermediate in the pathway for tryptophan-dependent auxin biosynthesis. The role of IAOx in growth-signalling and root phenotype is poorly studied in cruciferous plants and mostly unknown in non-cruciferous plants. We synthesized IAOx and applied it to M. truncatula plants grown axenically with NO3 -, NH4 + or urea as the sole nitrogen source. During 14 days of growth, we demonstrated that IAOx induced an increase in the number of lateral roots, especially under NH4 + nutrition, while elongation of the main root was inhibited. This phenotype is similar to the phenotype known as superroot previously described in SUR1- and SUR2-defective Arabidopsis mutants. The effect of IAOx, IAA or the combination of both on the root phenotype was different and dependent on the type of N-nutrition. Our results also showed the endogenous importance of IAOx in a legume plant in relation to IAA metabolism, and suggested IAOx long-distance transport depending on the nitrogen source provided. Finally, our results point out to CYP71A as the major responsible enzymes for IAA synthesis from IAOx, while they exclude indole-3-acetaldehyde oxidases. © 2019 Elsevier B.V.This work was supported by the grants AGL2017-86293-P and CGL2017-84723-P from the Spanish Ministry of Economy and Competitiveness (MINECO) , AGL2014-52396-P from the Ministry of Science Innovation and Universities (MICINN) , and IT932-16 from the Basque Government, Spain . JB and PL-G are holders of PhD fellowships from the Public University of Navarre. ACh received a Juan de la Cierva initiation grant FJCI-2016-27905 and RE received a Juan de la Cierva incorporation grant IJCI-2014-21452. This research was also supported by the Basque Government through the BERC 2018-2021 program, and by the Spanish Ministry of Science, Innovation and Universities through the BC3 María de Maeztu excellence accreditation (MDM-2017-0714)

Nonlinear optical properties of Au-nanoparticles conjugated with lipoic acid in water

Gold nanoparticles were chemically conjugated with lipoic acid to control their optical properties. Z-scan and other optical techniques were used to characterize the non-linear behavior of the resulting nanostructured materials. The results show that the nonlinearity is of thermal origin, which can be controlled by the use of lipoic acid as well as other organic molecules conjugated onto metal nanoparticles. In particular, the presence of lipoic acid increases n2 and dn/dT