Search results for " parti"
showing 10 items of 9465 documents
Coupling hydrodynamics and radiation calculations for star-jet interactions in active galactic nuclei
2016
Context. Stars and their winds can contribute to the non-thermal emission in extragalactic jets. Because of the complexity of jet-star interactions, the properties of the resulting emission are closely linked to those of the emitting flows. Aims. We simulate the interaction between a stellar wind and a relativistic extragalactic jet and use the hydrodynamic results to compute the non-thermal emission under different conditions. Methods. We performed relativistic axisymmetric hydrodynamical simulations of a relativistic jet interacting with a supersonic, non-relativistic stellar wind. We computed the corresponding streamlines out of the simulation results and calculated the injection, evolut…
Jet-torus connection in radio galaxies
2017
High-resolution Very-Long-Baseline Interferometry observations of active galactic nuclei have revealed asymmetric structures in the jets of radio galaxies. These asymmetric structures may be due to internal asymmetries in the jet, could be induced by the different conditions in the surrounding ambient medium including the obscuring torus, or a combination of the two. In this paper we investigate the influence of the ambient medium (including the obscuring torus) on the observed properties of jets from radio galaxies. We performed special-relativistic hydrodynamic (RHD) simulations of over-pressured and pressure-matched jets using the special-relativistic hydrodynamics code \texttt{Ratpenat}…
Correlation of the highest-energy cosmic rays with nearby extragalactic objects.
2007
Using data collected at the Pierre Auger Observatory during the past 3.7 years, we demonstrated a correlation between the arrival directions of cosmic rays with energy above ~ 6x10^{19} electron volts and the positions of active galactic nuclei (AGN) lying within ~ 75 megaparsecs. We rejected the hypothesis of an isotropic distribution of these cosmic rays with at least a 99% confidence level from a prescribed a priori test. The correlation we observed is compatible with the hypothesis that the highest energy particles originate from nearby extragalactic sources whose flux has not been substantially reduced by interaction with the cosmic background radiation. AGN or objects having a similar…
Long-term monitoring of mrk 501 for its very high energy γ emission and a flare in 2011 october
2012
"As one of the brightest active blazars in both X-ray and very high energy γ -ray bands, Mrk 501, is very useful for" "physics associated with jets from active galactic nuclei. The ARGO-YBJ experiment has monitored Mrk 501 for γ - rays above 0.3 TeV since 2007 November. The largest flare since 2005 was observed from 2011 October and lasted until about 2012 April. In this paper, a detailed analysis of this event is reported. During the brightest γ -ray flaring episodes from 2011 October 17 to November 22, an excess of the event rate over 6σ is detected by ARGO-YBJ in the direction of Mrk 501, corresponding to an increase of the γ -ray flux above 1 TeV by a factor of 6.6 ± 2.2 from its steady…
Dissipative Processes and Their Role in the Evolution of Radio Galaxies
2019
Particle acceleration in relativistic jets to very high energies occurs at the expense of the dissipation of magnetic or kinetic energy. Therefore, understanding the processes that can trigger this dissipation is key to the characterization of the energy budgets and particle acceleration mechanisms at action in active galaxies. Instabilities and entrainment are two obvious candidates to trigger dissipation. On the one hand, supersonic, relativistic flows threaded by helical fields, as expected from the standard formation models of jets in supermassive black-holes, are unstable to a series of magnetohydrodynamical instabilities, such as the Kelvin-Helmholtz, current-driven, or possibly the p…
Older people’s participation in political organizations: The role of generativity and its impact on well-being
2017
Aging population has increased a global concern to keep seniors active and healthy. Civic participation, in particular, has been highlighted for its social and community benefits and its impact on elders’ health and well-being. To date, however, most studies have explored volunteering; other types of civic activities, such as political participation, are largely overlooked. This study analyzes the relationship between older people’s active involvement in political organizations, generativity, and hedonic and eudaimonic well-being. We selected two samples of Spanish older people: a sample of elders actively involved in political organizations (n = 97) and a comparison group (n = 85). Measure…
Las políticas culturales en el sur de Europa tras la crisis global [Recurso electrónico] : su impacto en la participación cultural = Cultural policie…
2020
El último tercio del siglo XX supuso el inicio de un proceso de convergencia en la formulación y en la implementación de las políticas culturales de los países del sur de Europa con respecto al norte. Sin embargo, la crisis global ha conllevado un retroceso en los indicadores de participación cultural, rompiéndose la tendencia de la europeización de esta política pública. Analizamos desde un enfoque comparado, como la densidad institucional de la educación artística no formal, el sistema formal educativo y el tipo de gobernanza de los equipamientos culturales, determinan, además de los recortes públicos en la cultura, la mayor caída de la participación cultural en el modelo de política cult…
DO FLEXIBLE AND TENACIOUS GOAL PURSUIT ALLEVIATE THE INFLUENCES OF FUNCTIONAL DECLINE TO ACTIVITY PARTICIPATION?
2018
Assimilative and accommodative coping strategies have hardly been studied in relation to activity participation when facing functional decline. We investigated whether tenacious goal pursuit (TGP) and flexible goal adjustment (FGA) influence the association between physical or cognitive performance, and physical activity or participation in other hobbies. Participants were 78-93-year-old community-dwelling people (n=187). TGP and FGA were self-evaluated with distinct scales (ranges 5–25). Physical performance was assessed with Short Physical Performance Battery (SPPB; 0–12) and cognitive performance with Mini-Mental State Examination (MMSE; 0–30). Physical activity (0–5) and participation i…
Changes in Perfusion Pattern of Experimental Tumors Due to Reduction in Arterial Oxygen Partial Pressure
2006
The Small Size and Superficial Location Suggest That Laparoscopic Partial Nephrectomy Is the First Choice for the Treatment of Juxtaglomerular Cell T…
2021
BackgroundJuxtaglomerular cell tumor (JGCT) is a very rare disease, and surgical resection is the only possible way to cure this tumor. Open nephrectomy and partial nephrectomy have been reported to manage JGCTs with excellent results in the previous reviews. Laparoscopic surgery has been popularized in recent years, while critical issues associated with laparoscopic surgical management have been seldom reported. We summarized the JGCTs in our center to discover the optimal surgical management and its anatomic foundation.MethodsIn this retrospective study, we enrolled a total of 14 JGCT patients. All patients received surgeries and were followed up for up to 11 years. We mainly summarized t…