Systematic search for gamma-ray periodicity in active galactic nuclei detected by the Fermi Large Area Telescope

We use nine years of gamma-ray data provided by the Fermi Large Area Telescope (LAT) to systematically study the light curves of more than two thousand active galactic nuclei (AGN) included in recent Fermi-LAT catalogs. Ten different techniques are used, which are organized in an automatic periodicity-search pipeline, in order to search for evidence of periodic emission in gamma rays. Understanding the processes behind this puzzling phenomenon will provide a better view about the astrophysical nature of these extragalactic sources. However, the observation of temporal patterns in gamma-ray light curves of AGN is still challenging. Despite the fact that there have been efforts on characterizing the temporal emission of some individual sources, a systematic search for periodicities by means of a full likelihood analysis applied to large samples of sources was missing. Our analysis finds 11 AGN, of which 9 are identified for the first time, showing periodicity at more than 4sigma in at least four algorithms. These findings will help in solving questions related to the astrophysical origin of this periodic behavior.Comment: 16 pages, 5 figures, 4 tables. Accepted by Ap

Hemolytic activity and siderophore production in different aeromonas species isolated from fish

P. 5612-5614The hemolytic activity and siderophore production of several strains of motile aeromonads were determined. The hemolytic activity of Aeromonas caviae and Aeromonas eucrenophila was enhanced after trypsinization of the samples. The enhancement of hemolysis was observed in strains that carried an aerolysin-like gene, detected by a PCR procedure. Siderophore production was demonstrated in all but one strain of Aeromonas jandaei. No apparent relationship was observed between the presence of plasmid DNA and hemolysis or siderophore production.S

Multiwavelength Analysis of Fermi-LAT Blazars with High-Significance Periodicity: Detection of a Long-Term Rising Emission in PG 1553+113

Blazars display variable emission across the entire electromagnetic spectrum, with timescales that can range from a few minutes to several years. Our recent work has shown that a sample of five blazars exhibit hints of periodicity with a global significance $\gtrsim2\,\sigma$ at $\gamma$-ray energies, in the range of 0.1~GeV$<$E$<$800~GeV. In this work, we study their multiwavelength (MWL) emission, covering the X-ray, ultraviolet, optical, and radio bands. We show that three of these blazars present similar periodic patterns in the optical and radio bands. Additionally, fluxes in the different bands of the five blazars are correlated, suggesting a co-spatial origin. Moreover, we detect a long-term ($\approx$10 year) rising trend in the light curves of PG~1553+113, and we use it to infer possible constraints on the binary black hole hypothesis.Comment: 20 pages, 10 figures, 7 table

Errores de medicación en niños que acuden a los servicios de urgencias pediátricas

Errores de medicación; Servicios de urgencias; PediatríaMedication errors; Emergency departments; PediatricsErrors de medicació; Servei d'urgències; PediatriaObjectives: Medication safety represents an important challenge in children. There are limited studies on medication errors in pediatric patients visiting emergency departments. To help bridge this gap, we characterized the medication errors detected in these patients, determining their severity, the stages of the medication process in which they occurred, the drugs involved, and the types and causes associated with the errors. Methods: We conducted a multicenter prospective observational study in the pediatric emergency departments of 8 Spanish public hospitals over a 4-month period. Medication errors detected by emergency pediatricians in patients between 0 and 16 years of age were evaluated by a clinical pharmacist and a pediatrician. Each medication error was analyzed according to the updated Spanish Taxonomy of Medication Errors. Results: In 99,797 visits to pediatric emergency departments, 218 (0.2%) medication errors were detected, of which 74 (33.9%) resulted in harm (adverse drug events). Preschoolers were the age group with the most medication errors (126/218). Errors originated mainly in the prescribing stage (66.1%), and also by self-medication (16.5%) and due to wrong administration of the medication by family members (15.6%). Dosing errors (51.4%) and wrong/improper drugs (46.8%) were the most frequent error types. Anti-infective drugs (63.5%) were the most common drugs implicated in medication errors with harm. Underlying causes associated with a higher proportion of medication errors were "medication knowledge deficit" (63.8%), "deviation from procedures/guidelines" (48.6%) and "lack of patient information" (30.3%). Conclusions: Medication errors presented by children attending emergency departments arise from prescriptions, self-medicationand administration, and lead to patient harm in one third of cases. Developing effective interventions based on the types of errors and the underlying causes identified will improve patient safety.Objetivos La seguridad de medicamentos en pediatría supone un verdadero reto. Se dispone de escasos estudios que hayan analizado los errores de medicación en los pacientes pediátricos que acuden a los servicios de urgencias. El objetivo de este estudio ha sido caracterizar los errores detectados en estos pacientes, determinando su severidad, los procesos afectados, los medicamentos implicados, y los tipos de errores y causas asociados. Métodos Estudio multicéntrico observacional prospectivo realizado en los servicios de urgencias de 8 hospitales públicos españoles durante 4 meses. Los errores de medicación detectados por los pediatras de urgencias en pacientes entre 0 y 16 años fueron evaluados por un farmacéutico y un pediatra. Los errores de medicación fueron analizados utilizando la Taxonomía Española de Errores de Medicación actualizada. Resultados En 99.797 visitas a urgencias se detectaron 218 (0,2%) errores de medicación, de los cuales 74 (33,9%) causaron daños (eventos adversos por medicamentos). Los preescolares fueron el grupo poblacional con mayor número de errores de medicación (126/218). Los errores se originaron mayoritariamente en la prescripción (66,1%), por automedicación (16,5%) y por administración equivocada por parte de familiares (15,6%). Los tipos de errores más frecuentes fueron “dosis incorrectas” (51,4%) y “medicamento inapropiado” (46,8%). Los antiinfecciosos (63,5%) fueron los fármacos más comúnmente implicados en los errores con daño. Las causas subyacentes asociadas a una mayor proporción de errores de medicación fueron: “falta de conocimiento del medicamento” (63,8%), “falta de seguimiento de los procedimientos” (48,6%) y “falta de información del paciente” (30,3%). Conclusiones Los errores de medicación en la población pediátrica que acude a urgencias se producen en la prescripción, por automedicación y en la administración, provocando daños a los pacientes en un tercio de las ocasiones. Desarrollar prácticas seguras basadas en los tipos de errores detectados y sus causas subyacentes, mejorará la seguridad de los pacientes.This study has been carried out with the support of a grant provided by the Spanish Society of Hospital Pharmacists for the period 2015–2016

Variability and evolution of the optical polarization of a sample of gamma-ray blazars

We present a polarization variability analysis of a sample of 26 $\gamma$-ray blazars monitored by the Steward Observatory between 2008 and 2018 in the optical band. We investigate the properties and long-term variability of their optical polarization, searching for differences between blazar types. We observe that BL Lac objects are typically less polarized and less variable than flat spectrum radio quasars (FSRQs). Moreover, BL Lacs display a distribution of their polarization angle typically oriented in a preferential direction, contrary to the rather random distribution of FSRQs. For the latter blazar type, as well as those sources showing a bright stellar emission, we take into account the depolarizing effect introduced by the broad line region and the host galaxy on the measured polarization degree. In this sample we also observe that BL Lacs present an uncorrelated evolution of the flux and the polarization. Contrary, FSRQs show a correlation before the depolarization correction, that is lost however after considering this effect. In addition, we study the behaviour of the polarization angle, searching for angle rotations in its long-term evolution. We derive that the FSRQs studied here show rotations more frequently than BL Lac objects by a factor $\sim$1.5. During these periods we also observe a systematic decrease of the polarization fraction, as well as a marginal flux increase, not significant however to connect rotations with optical flares. We interpret these results within the extended shock-in-jet scenario, able to explain the overall features observed here for the polarization of the blazar sample.Comment: Accepted for publication in MNRA

Effects of LED lighting on Nannochloropsis oceanica grown in outdoor raceway ponds

Growth in most microalgal mass cultivation systems is light-limited, particularly in raceway ponds (RWP) where the light path is higher. Artificial lighting can be a promising solution to diminishing dark zones and enhance microalgal productivity. Therefore, our goal was to prevent the cell shift from photosynthesis to a respiration-only stage by resorting to LED illumination. Nannochloropsis oceanica cultures were accordingly grown out-doors in a preliminary small-scaleexperiment, followed by pilot-scale trials. In the former, three 3.0-m(2) RWP were set up under three distinct conditions: 1) without LEDs (control); 2) LEDs turned on during the night; and 3) LEDs turned on for 24 h. In the pilot-scale trial, one of two 28.9-m(2) pilot-scale RWPs was coupled to the best LED setup - determined in the small-scale preliminary experiment - using the same light intensity (normal mode) and half of the intensity (economy mode), with the second RWP serving as a control. In the preliminary experiment, the use of LEDs for 24 h was deemed as not helpful during daytime, before the culture reached asymptotic to 0.5 g DW L-1 - when dark zones appeared during the day due to sunlight attenuation in the 0.1 m-deep cultures. Overall, use of LEDs increased biomass growth chiefly by increasing nighttime productivities - materialized in higher chlorophyll, protein, and carbohydrate productivities in LED-lit cultures. A higher impact of LED lighting was observed under lower sunlight irradiances. A preliminary economic analysis indicates that use of LEDs in RWPs outdoors should be considered for high-value metabolites only.info:eu-repo/semantics/publishedVersio

A Nonzero Gap Two-Dimensional Carbon Allotrope from Porous Graphene

Graphene is considered one of the most promising materials for future electronic. However, in its pristine form graphene is a gapless material, which imposes limitations to its use in some electronic applications. In order to solve this problem many approaches have been tried, such as, physical and chemical functionalizations. These processes compromise some of the desirable graphene properties. In this work, based on ab initio quantum molecular dynamics, we showed that a two-dimensional carbon allotrope, named biphenylene carbon (BPC) can be obtained from selective dehydrogenation of porous graphene. BPC presents a nonzero bandgap and well-delocalized frontier orbitals. Synthetic routes to BPC are also addressed.Comment: Published on J. Phys. Chem. C, 2012, 116 (23), pp 12810-1281

Intravitreal implants manufactured by supercritical foaming for treating retinal diseases

Chronic retinal diseases, such as age-related macular degeneration (AMD), are a major cause of global visual impairment. However, current treatment methods involving repetitive intravitreal injections pose financial and health burdens for patients. The development of controlled drug release systems, particularly for biological drugs, is still an unmet need in prolonging drug release within the vitreous chamber. To address this, green supercritical carbon dioxide (scCO2) foaming technology was employed to manufacture porous poly(lactic-co-glycolic acid) (PLGA)-based intravitreal implants loaded with dexamethasone. The desired implant dimensions were achieved through 3D printing of customised moulds. By varying the depressurisation rates during the foaming process, implants with different porosities and dexamethasone release rates were successfully obtained. These implants demonstrated controlled drug release for up to four months, surpassing the performance of previously developed implants. In view of the positive results obtained, a pilot study was conducted using the monoclonal antibody bevacizumab to explore the feasibility of this technology for preparing intraocular implants loaded with biologic drug molecules. Overall, this study presents a greener and more sustainable alternative to conventional implant manufacturing techniques, particularly suited for drugs that are susceptible to degradation under harsh conditions

Preliminary study of the variations on the spatio-temporal distribution of a potentially exploitable species (Patagonotothen spp.) in the southwest Atlantic, using GIS techniques

The genus Patagonotothen is the most common Nototheniid on the Patagonian Shelf and slope and is part of the by-catch species in the bottom trawl fisheries. This paper presents preliminary results from the EC CRAFT project “Promoting higher added value to a finfish species rejected to sea”, aiming to develop the research and the technology necessary to promote higher added value to fishing activity by taking profit from a finfish species (Rockcod, Patagonotothen spp.) not known to consumers and currently discarded by the EU fishing fleet operating in the South West Atlantic in order to supply the EU seafood industry with a good quality raw material for human food manufacturing. Historical fishery data series (26 168 commercial hauls of which 12 745 were positive), including effort, catches and discards, as well as biological and environmental information, from 1988 onwards was used to describe and quantify patterns and spatio-temporal changes in the rockcod fishery. These data was collected by scientific observers on board commercial vessels.GIS analysis was carried out in order to study the seasonal geographical changes in the distribution of abundance, SST and densities calculated from CPUE. Fishery and environmental data as well as SST data derived from the NOAA Advanced Very High Resolution Radiometer (AVHRR), were analysed in order to find monthly variations in spatial and depth distribution of Patagonotothen spp. Preliminary results demonstrated that, within areas of occurrence, there are significant correlations between fish abundance (CPUE), the oceanographic conditions of the area (SST gradients) and depth in certain months