3,740 research outputs found
On the origin of two unidentified radio/X-ray sources discovered with XMM-Newton
We aim at clarifying the nature of the emission of two spatially related
unidentified X-ray sources detected with XMM-Newton telescope at
intermediate-low Galactic latitude. Observations reveal a point-like source
aligned with elongated diffuse emission. The X-ray spectra are best-fitted by
absorbed power laws with photon indices ~1.7 for the point-like and ~2.0 for
the extended one. Both sources show nonthermal radio-continuum counterparts
that might indicate a physical association. From the available data, we did not
detect variability on the point-like source in several timescales. Two possible
scenarios are analyzed: first, based on HI line absorption, assuming a Galactic
origin, we infer a distance upper bound of <2 kpc, which poses a constraint on
the height over the Galactic plane of <200 pc and on the linear size of the
system of 10^32 erg/s and
>7.5 x 10^32 erg/s, for the point-like and extended sources, respectively;
second, an extra-Galactic nature is discussed, where the point-like source
might be the core of a radio galaxy and the extended source its lobe. In this
case, we compare derived fluxes, spectral indices, and spatial correlation with
those typical from the radio galaxy population, showing the feasibility of this
alternative astrophysical scenario. From the available observational evidence,
we suggest that the most promising scenario to explain the nature of these
sources is a system consisting of a one-sided radio galaxy, where the
point-like source is an active galactic nucleus and the extended source
corresponds to the emission from its lobe. Other possibilities include a
PSR/PWN origin, where the radio/X-ray emission originates from the synchrotron
cooling of relativistic particles in the PSR magnetic field or a casual
alignment between two unrelated sources, such as an AGN core and a Galactic
X-ray blob.Comment: 6 pages, 2 figures. Accepted for publication in Astronomy and
Astrophysics (A&A
Nanoplastics: From tissue accumulation to cell translocation into Mytilus galloprovincialis hemocytes. resilience of immune cells exposed to nanoplastics and nanoplastics plus Vibrio splendidus combination
Plastic litter is an issue of global concern. In this work Mytilus galloprovincialis was used to study the distribution and effects of polystyrene nanoplastics (PS NPs) of different sizes (50 nm, 100 nm and 1 mu m) on immune cells. Internalization and translocation of NPs to hemolymph were carried out by in vivo experiments, while endocytic routes and effects of PS NPs on hemocytes were studied in vitro. The smallest PS NPs tested were detected in the digestive gland and muscle. A fast and size-dependent translocation of PS NPs to the hemolymph was recorded after 3 h of exposure. The internalization rate of 50 nm PS NPs was lower when caveolae and clathrin endocytosis pathways were inhibited. On the other hand, the internalization of larger particles decreased when phagocytosis was inhibited. The hemocytes exposed to NPs had changes in motility, apoptosis, ROS and phagocytic capacity. However, they showed resilience when were infected with bacteria after PS NP exposure being able to recover their phagocytic capacity although the expression of the antimicrobial peptide Myticin C was reduced. Our findings show for the first time the translocation of PS NPs into hemocytes and how their effects trigger the loss of its functional parameters
Experimental and computational study of the effect of temperature on the electro-polymerization process of Thiophene
Temperature effect on the nucleation and growth mechanisms (NGM) of poly(thiophene) (PTh) was investigated through experimental and computational tools. The computational simulation method was based on a kinetic Monte Carlo algorithm. It reproduced key processes such as diffusion, oligomerization, and the precipitation of oligomers onto the electrode surface. Electrochemical synthesis conditions at temperatures between 263 and 303 K were optimized. The deconvolution of the i-t transients reflected two contributions: a progressive nucleation with three-dimensional growth controlled by diffusion and the other by charge transfer, PN3Ddif and PN3Dct, respectively. As temperature decreased, a diminution of the charge associated to each contribution was observed and the nucleation induction time increased. Experimental and computational evidence indicated that temperature does not change the nucleation and growth mechanism (NGM). This effect was ascribed to kinetic factors rather than to film conductivity. This work contrasts simulation and experimental evidence and demonstrates how computational simulations can help to understand the electrochemical process of conducting polymers formation.Fil: Camarada, María Belén. Pontificia Universidad Católica de Chile; Chile. Universidad de Talca; ChileFil: Romero, M.. Pontificia Universidad Católica de Chile; ChileFil: Gimenez, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Schmickler, Wolfgang. Universitat Ulm; AlemaniaFil: del Valle, M. A.. Pontificia Universidad Católica de Chile; Chil
Deployment of Digital Video and Audio Over Electrical SCADA Networks
With the arrival of new hardware and software technologies,
supervisory control and data acquisition human-machine
interfaces (SCADA/HMI), usually text-based, can now benefit
from the advantages the inclusion of multimedia information
brings. However, due to the special requirements imposed by
such systems, integrating audio and video data into the SCADA
interfaces is not a trivial task. In this document we analyze those
special characteristics and propose solutions so this integration is
possible in power systems communication.Ministerio de Ciencia y Tecnología TIC2000-0367-P4-0
Image zooming based on sampling theorems
In this paper we introduce two digital zoom methods based on sampling theory and we study their mathematical foundation. The first one (usually known by the names of "sinc interpolation", "zero-padding" and "Fourier zoom") is commonly used by the image processing community
Las danzas rituales y procesionales en la ribera del Júcar (Valencia)
En número dedicado a: Valenci
Correlations between Elastic, Calorimetric, and Polar Properties of Ferroelectric PbSc0.5Ta0.5O3 (PST)
Calorimetric, elastic, and polar properties of ferrolectric lead scandium tantalate PbSc0.5Ta0.5O3 (PST) with 65% cation
order have been investigated in the vicinity of the paraelectric-ferroelectric transition at Ttrans = 295K. Comparison of
temperature dependencies of the excess specific heat and elastic properties indicate that both anomalies stem from ther-
mal fluctuations of order parameters in three dimensions. These fluctuations are consistent with tweed microstructure.
This transition is driven by several coupled thermodynamic order parameters, as evidenced by a strongly non-linear
scaling of the excess entropy with the squared ferroelectric polarization.National Natural Science Foundation of China (51850410520, 51320105014 and 51621063
Trunk injection of fosetyl-aluminium controls the root disease caused by Phytophthora cinnamomi on Quercus ilex woodlands
In Spain, Quercus open woodlands are animal ranching systems of organic production seriously threatened by the exotic pathogen Phytophthora cinnamomi. The root disease it causes kills thousands of oaks annually. Effective disease management needs to integrate different techniques, and the use of a resistance inducer such as fosetyl‐Al can play a key role, because the use of potassium phosphite is prohibited in Spain. In a woodland where the pathogen recently arrived, 60 holm oaks in three different defoliation classes (asymptomatic, slight and moderate defoliation) were selected for trunk injection with pressurised capsules containing 4% of commercial fosetyl‐Al or water (controls). Holm oaks were checked periodically for defoliation and presence of the pathogen in roots and rhizosphere soil. Three years after treatments, defoliation was significantly lower in oaks treated with fosetyl‐Al, which even increased canopy cover, in comparison with control oaks, independent of the initial defoliation class considered. Chlamydospore density in rhizosphere soil, as well as the presence of the pathogen into the roots, was not significantly influenced by fosetyl‐Al treatments, although a trend to a lower presence of P. cinnamomi in roots was observed in treated oaks at every soil inoculum density detected. This study has shown that fosetyl‐Al, a phosphonate registered as a fungicide in the European Union, provides protection to holm oaks against P. cinnamomi, even exhibiting a therapeutic effect on pre‐existing infections. Consequently, this effective measure should be considered as part of the integrated approach to control this highly destructive pathogen in holm oak woodlands
Percusión Corporal y TDAH en el método BAPNE. Introducción metodológica
En este artículo justificamos el uso terapéutico de la percusión corporal según el método Bapne en el trastorno de Déficit de Atención e Hiperactividad TDAH. Los sujetos con este tipo de trastorno se caracterizan por presentar dificultades vinculadas a la regulación de la conducta y especialmente por tener dificultades en las funciones ejecutivas. Dicha disfunción ejecutiva pone de relieve una pobre memoria de trabajo, verbal y no verbal, dificultades en la regulación del afecto, la motivación y la excitación, dificultades para analizar una situación, para planificar y organizarse y dificultades para inhibir respuestas. Bajo el paraguas de la teoría de los comportamientos enmascaradores, estas vivencias de fracaso, dificultad y estrés quedan almacenadas en el inconsciente emocional y desembocan en la configuración de un patrón de respuesta de defensa y protección. Desde el método Bapne, sostenemos que la práctica de la percusión corporal terapéutica ayuda a reconfigurar estos patrones de respuesta habitual, favoreciendo la auto percepción de auto competencia mediante el aprendizaje entre iguales, estimulando la memoria de trabajo, la empatía, mejorando la autoestima y muy especialmente facilitando la autonomía en la atención
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