PURPOSE Existing flare photometers are based on the Tyndall effect, which requires sophisticated laser photometry. The ocular flare analysis meter (OFAM) is a nonlaser photometer that uses quantitative Rayleigh scatter and absorption from visible light to compute a flare value. This study is designed to correlate OFAM measurements with qualitative measurements of flare in vitro and in vivo. M...

Abstract Background: Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare, autosomal dominant disorder driven by mutations in ACVR1 that render it responsive to Activin A. FOP characterized progressive heterotopic ossification (HO) and distressing inflammatory events called “flare-ups.” Flare-ups can precede new HO; however, limited prospective data exists on this phenomenon. Garetosmab...

In this paper we report a significant magnetic anomaly, specifically an apparent sign reversal of magnetic polarities in small areas of Michelson Doppler Imager (MDI) magnetograms during the impulsive phase of an X5.6 flare on 2001April 6. Three flare kernels were observed to emit 50 keV hardX-rays, which are located in strong magnetic fields of order 1000–1500 G. We find that the apparent sign...

“Elementary bursts” refer to fine time structures on scales of tens of milli-second to a few seconds in flare radiations. In this paper, we investigate temporal and spatial properties of elementary bursts by exploiting high-cadence Hα (100 ms) and hard X-ray (125 – 500 ms) observations of an impulsive flare on March 16, 2000. We find that the time scale of 2 – 3 s is likely an upper limit of th...

The physical processes that trigger solar flares are not well understood and significant debate remains around processes governing particle acceleration, energy partition, and particle and energy transport. Observations at high resolution in energy, time, and space are required in multiple energy ranges over the whole course of many flares in order to build an understanding of these processes. ...

NGC 247 is a nearby late-type bulgeless spiral galaxy that contains an inactive nucleus. We report a serendipitous discovery of an X-ray flare from the galaxy center with a luminosity of up to 2 1039 ́ erg s in the 0.3–10 keV band with XMM-Newton. A Chandra observation confirms that the new X-ray source is spatially coincident with the galaxy nucleus. The XMM-Newton data revealed a hard power-la...

After nearly two years of quiescence, the soft gamma-ray repeater SGR 1900+14 again became burst-active on April 18 2001, when it emitted a large flare, preceded by few weak and soft short bursts. After having detected the X and gamma prompt emission of the flare, BeppoSAX pointed its narrow field X-ray telescopes to the source in less than 8 hours. In this paper we present an analysis of the d...

We perform a multi-wavelength study of a two-ribbon flare on 2002 September 29 and its associated filament eruption, observed simultaneously in the Hα line by a ground-based imaging spectrograph and in hard X-rays by RHESSI. The flare ribbons contain several Hα bright kernels that show different evolutional behaviors. In particular, we find two kernels that may be the footpoints of a loop. A si...

This article discusses statistical models for solar flare interval distribution in individual active regions. We analyzed solar flare data in 55 active regions that are listed in the Geosynchronous Operational Environmental Satellite (GOES) soft X-ray flare catalog for the years from 1981 to 2005. We discuss some problems with a conventional procedure to derive probability density functions fro...

We analyze the temporal behavior of Network Bright Points (NBPs) searching for low-atmosphere signatures of flares occuring on the magnetic network. We make use of a set of data acquired during coordinated observations between ground based observatories (NSO/Sacramento Peak) and the MDI instrument onboard SOHO. Light curves in chromospheric spectral lines show only small amplitude temporal vari...