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Context. Since 2001, the radio quasar 3C 454.3 has undergone a period of high optical activity, culminating in the brightest optical state ever observed, during the 2004-2005 outburst. The Whole Earth Blazar Telescope (WEBT) consortium has carried out several multifrequency campaigns to follow the source behaviour.Aims. The GLAST-AGILE Support Program (GASP) was born from the WEBT to provide long-term continuous optical-to-radio monitoring of a sample of ?-loud blazars, during the operation of the AGILE and GLAST (now known as Fermi GST) ?-ray satellites. The main aim is to shed light on the mechanisms producing the high-energy radiation, through correlation analysis with the low-energy emission. Thus, since 2008 the monitoring task on 3C?454.3 passed from the WEBT to the GASP, while both AGILE and Fermi detected strong ?-ray emission from the source.Methods. We present the main results obtained by the GASP at optical, mm, and radio frequencies in the 2008-2009 season, and compare them with the WEBT?results from previous years.Results. An optical outburst was observed to peak in mid July?2008, when Fermi detected the brightest ?-ray levels. A?contemporaneous mm outburst maintained its brightness for a longer time, until the cm emission also reached the maximum levels. The behaviour compared in the three bands suggests that the variable relative brightness of the different-frequency outbursts may be due to the changing orientation of a curved inhomogeneous jet. The optical light curve is very well sampled during the entire season, which is also well covered by the various AGILE and Fermi observing periods. The relevant cross-correlation studies will be very important in constraining high-energy emission models.

Context. The transition from the asymptotic giant branch (AGB) to the planetary nebula (PN) phase is critical in the shaping of PNe. It has been suggested that the most asymmetric PNe are the descendants of massive AGB?stars. Since these AGB?stars are believed to have evolved into heavily obscured post-AGB stars and PNe, the compilation of a sample of bona fide obscured post-AGB stars and PNe is important for understanding the formation of asymmetric PNe.Aims. We aim to identify and characterize a large number of post-AGB stars and PNe in the IR and to assess their degree of optical obscuration. The improved positions will enable future detailed studies to determine their true nature, whereas the optical and IR?properties can be used to investigate their spectral behavior.Methods. We used 2MASS, Spitzer GLIMPSE, MSX, and IRAS data in search of the near-IR counterparts of a sample of 165 presumably obscured IRAS post-AGB and PN?candidates, and DSS?red images to identify the optical counterparts among the objects detected in the near-IR. The IR spectral energy distributions (SEDs) in the wavelength range from 1??m to 100??m of the sources with unambiguous near-IR counterparts were analyzed using appropriate color-color diagrams. Results. We have identified the near-IR counterparts of 119?sources out of the 165?IRAS post-AGB and PN candidates in our sample. The improved astrometric coordinates of these sources have allowed us to find optical counterparts for 59 of them, yielding a reduced sample of?60 optically obscured post-AGB star and PN?candidates. Among the 119?sources with near-IR counterparts, only 80 have unambiguous identifications in the 2MASS Point Source Catalogue. For these sources, we find that objects with and without optical counterparts, while having similar mid- and far-IR colors, are segregated in color-color diagrams that use the near-IR J?band to compute one of the colors.

Aims. We report the detection by the AGILE satellite of a rapid ?-ray flare from the source 1AGL J1511-0908, associated with the powerful ?-ray quasar PKS 1510-089, during a pointing centered on the Galactic center region from 1 March to 30 March 2008. This source has been continuosly monitored in the radio-to-optical bands by the GLAST-AGILE Support Program (GASP) of the Whole Earth Blazar Telescope (WEBT). Moreover, the ?-ray flaring episode triggered three ToO observations by the Swift satellite in three consecutive days, starting from 20 March 2008. The quasi-simultaneous radio-to-optical, UV, X-ray and ?-ray coverage allows us to make a detailed study of the multifrequency time evolution, the spectral energy distribution of this source, and its theoretical interpretation based on the synchrotron and inverse Compton?(IC) emission mechanisms.Methods. During the radio-to-optical monitoring provided by the GASP-WEBT, AGILE observed the source with its two co-aligned imagers, the gamma-ray imaging detector (GRID) and the hard X-ray imager (SuperAGILE), which are sensitive in the 30?MeV?30?GeV and 18?60?keV energy bands, respectively.Results. In the period 1?16?March 2008, AGILE detected ?-ray emission from PKS 1510-089 at a significance level of 6.2-? with an average flux over the entire period of (84 ?17) ?10-8?photons?cm-2s-1for photon energies above 100?MeV. After a predefined satellite re-pointing, between 17 and 21 March 2008, AGILE detected the source at a significance level of 7.3-?, with an average flux (E > 100?MeV) of (134 ?29) ?10-8?photons?cm-2?s-1and a peak level of (281 ?68) ?10-8?photons?cm-2?s-1with daily integration. During the observing period January-April 2008, the source also showed an intense and variable optical activity, with several flaring episodes and a significant increase in the flux was observed at millimetric frequencies. Moreover, in the X-ray band, the Swift/XRT observations seem to show a harder-when-brighter behavior of the source spectrum.Conclusions. The flat spectrum radio quasar PKS?1510-089 showed strong activity between January and April 2008, with episodes of rapid variability from radio to ?-ray energy bands, in particular with a rapid ?-ray flaring episode. The spectral energy distribution of mid-March 2008 is modeled with a homogeneous one-zone synchrotron self Compton (SSC) emission plus contributions from inverse Compton scattering of external photons from both the accretion disk and the broad line region. Indeed, some features in the optical-UV spectrum seem to indicate Seyfert-like components such as the little and the big blue bumps.

We present a possible scenario for the ejection of a superluminal component in the jet of the Broad Line Radio Galaxy 3C?111 in early 1996. VLBI observations at 15?GHz discovered the presence of two jet features on scales smaller than one parsec. The first component evolves downstream, whereas the second one fades out after 1?parsec. We propose the injection of a perturbation of dense material followed by a decrease in the injection rate of material in the jet as a plausible explanation. This scenario is supported by 1D relativistic hydrodynamic and emission simulations. The perturbation is modeled as an increase in the jet density, without modifying the original Lorentz factor in the initial conditions. We show that an increase of the Lorentz factor in the material of the perturbation fails to reproduce the observed evolution of this flare. We are able to estimate the lifetime of the ejection event in 3C?111 to be 36?? 7?days.

Context. The quasar-type blazar 3C 454.3 underwent a phase of high activity in summer and autumn?2007 that was intensively monitored in the radio-to-optical bands by the Whole Earth Blazar Telescope (WEBT). The ?-ray satellite Astro-rivelatore Gamma a Immagini LEggero (AGILE) detected this source first in late July, and then in November?December 2007.Aims. We present the multifrequency data collected by the WEBT and collaborators during the second AGILE observing period, complemented by contemporaneous data from the UltraViolet and Optical Telescope (UVOT) onboard the Swift satellite. The aim is to trace in detail the behaviour of the synchrotron emission from the blazar jet, and to investigate the contribution from the thermal emission component.Methods. Optical data from about twenty telescopes have been homogeneously calibrated and carefully assembled to construct an R-band light curve containing about 1340?data points over 42?days. This extremely well-sampled optical light curve allows us to follow the dramatic flux variability of the source in detail. In addition, we show radio-to-UV spectral energy distributions (SEDs) at different epochs, which represent different brightness levels.Results. In the considered period, the source varied by 2.6?mag over two weeks in the R?band. Many episodes of fast (i.e.?intranight) variability were observed, most notably on December?12, when a flux increase of about 1.1?mag in 1.5?h was detected, followed by a steep decrease of about 1.2?mag in 1?h. The contribution by the thermal component is difficult to assess, due to the uncertainties in the Galactic, and possibly also intrinsic, extinction in the UV?band. However, polynomial fitting of radio-to-UV?SEDs reveals an increasing spectral bending towards fainter states, suggesting a UV?excess likely due to the thermal emission from the accretion disc.Conclusions. Once the AGILE data are completely analysed, the low-frequency observations presented in this letter will offer a powerful tool to investigate optical-? flux correlations, i.e.?the relationship between the synchrotron and inverse-Compton emission components.

The effect of lipid profile, vitamin E and total phenolic content was studied in relation to the antioxidant capacity (measured by ESR) of three edible oils (virgin olive, sunflower and olive oils), using short-time deep fat frying as a model. Physico-chemical changes in the oils were also studied. Samples were analysed before and after 15, 30, 45 and 60 min fryings. Determination of free radicals, by electron spin resonance spectroscopy, revealed the highest antioxidant capacity in virgin olive oil and sunflower oil. This parameter was mainly influenced by vitamin E content, followed by lipid profile and phenolic content. The frying procedure decreased the antioxidant capacity in all tested oils. Sunflower oil underwent more chemical changes by frying than did olive and virgin olive oils. Antioxidant capacity of the edible oils was correlated with polar components and ultraviolet indices but not with peroxide index or acidity value. The use of ESR, as a rapid and very sensitive method for determining antioxidant capacity of edible oils, is suggested.

This paper addresses the question of up to what extent there are changes in the jovian jets as seen at cloud level and how they relate to the cloud morphology changes. We focus on the particularly interesting region at 24°N where the most intense jovian jet as observed at visual wavelengths resides. The studied period goes from 1991 to 1998, and the analysis is based on CCD images obtained with ground-based telescopes, complemented with a set from the HST imagery archive in the spectral range from ∼300 to 890 nm. The morphology of the North Temperate Belt (NTB) was characterized by the presence of a series of long-lived spots with lifetimes >4 years that formed in the anticyclonic flank of the jet at planetographic latitude 23.3 N following the development of the 1990 large-scale disturbance that changed the albedo of this belt (Sanchez-Lavega et al. 1991). They are rapidly moving mid-scale ovals (zonal velocity 123.9 ms−1, mean size ∼6500 km east–west times 3200 km north–south) with weak anticyclonic vorticity. The detailed structure of the zonal wind velocity profile of the 23.7°N jet between 1994 and 1998 was also measured using both cloud tracking and a correlation technique based on zonal reflectivity profiles. The jet peak speed during the 1994–1998 period appeared to be about 50 ms−1 slower and its shape broader in latitude when compared to that measured with the Voyager's in 1979. It seems that the differences in the profile between 1979 and the 1990s are related to the observed different cloud morphology in the region.