21 research outputs found

    Multifrequency variability of the blazar AO 0235+164 the WEBT campaign in 2004-2005 and long-term SED analysis

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    A huge multiwavelength campaign targeting the blazar AO 0235+164 was organized by the Whole Earth Blazar Telescope (WEBT) in 2003-2005 to study the variability properties of the source. Monitoring observations were carried out at cm and mm wavelengths, and in the near-IR and optical bands, while three pointings by the XMM-Newton satellite provided information on the X-ray and UV emission. We present the data acquired during the second observing season, 2004-2005, by 27 radio-to-optical telescopes. They reveal an increased near-IR and optical activity with respect to the previous season. Increased variability is also found at the higher radio frequencies, down to 15 GHz, but not at the lower ones. The radio (and optical) outburst predicted to peak around February-March 2004 on the basis of the previously observed 5-6 yr quasi-periodicity did not occur. The analysis of the optical light curves reveals now a longer characteristic time scale of 8 yr, which is also present in the radio data. The spectral energy distributions corresponding to the XMM-Newton observations performed during the WEBT campaign are compared with those pertaining to previous pointings of X-ray satellites. Bright, soft X-ray spectra can be described in terms of an extra component, which appears also when the source is faint through a hard UV spectrum and a curvature of the X-ray spectrum. Finally, there might be a correlation between the X-ray and optical bright states with a long time delay of about 5 yr, which would require a geometrical interpretation

    First sagittarius A* Event Horizon Telescope results. VI. Testing the black hole metric

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    Galaxie

    A universal power-law prescription for variability from synthetic images of black hole accretion flows

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    Instrumentatio

    Millimeter light curves of sagittarius A* observed during the 2017 Event Horizon Telescope campaign

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    Galaxie

    First sagittarius A* Event Horizon Telescope results. IV. Variability, morphology, and black hole mass

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    Galaxie

    First M87 Event Horizon Telescope results. IX.: detection of near-horizon circular polarization

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    Galaxie

    Characterizing and mitigating intraday variability: reconstructing source structure in accreting black holes with mm-VLBI

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    Instrumentatio

    First Sagittarius A* Event Horizon Telescope results. I. The shadow of the supermassive black hole in the center of the Milky Way

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    Galaxie

    First Sagittarius A* event horizon telescope results. II. EHT and multiwavelength observations, data processing, and calibration

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    Instrumentatio

    Cost-effectiveness of infant orthopedic treatment regarding speech in patients with complete unilateral cleft lip and palate: a randomized three-center trial in the Netherlands (Dutchcleft).

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    Contains fulltext : 57384.pdf (publisher's version ) (Closed access)OBJECTIVE: To investigate the cost-effectiveness of infant orthopedic treatment (IO), compared with no such treatment in children with complete unilateral cleft lip and palate (UCLP) focusing on the effects on speech development at age 2.5 years. DESIGN: In a three-center prospective, randomized clinical trial (Dutchcleft), two groups of children with complete UCLP were followed longitudinally: one group was treated with IO based on a modified Zurich approach in the first year of life (IO group) and the other group did not receive this treatment (non-IO group). PATIENTS: The participants had complete UCLP without soft tissue bands or other malformations. They were born at term and their parents were native Dutch speakers. OUTCOME MEASURES: The effect of IO on speech development at age 2.5 years was measured blindly by five expert listeners judging the "total impression of speech quality" on a 10-point equal-appearing interval scale. Costs were measured from a societal viewpoint in Euro. RESULTS AND CONCLUSION: The IO group (n = 10) obtained a statistically significant higher rating, compared with the non-IO group (n = 10). The effect size was large, indicating that the improvement may be considered a clinically important change. The cost for treatment by the orthodontist was higher in the IO group. For both groups, the mean cost was related to the mean rating for "total impression of speech quality." The resulting cost-effectiveness for IO, compared to non-IO was 1041 for 1.34 point speech quality improvement. The financial investment that is necessary to obtain this improvement seems limited. Thus, from the perspective of speech development, the cost-effectiveness of IO over non-IO seems acceptable at this point in time
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