RESUMEN
A statistical study of the chromospheric ribbon evolution in H[Formula: see text] two-ribbon flares was performed. The data set consists of 50 confined (62%) and eruptive (38%) flares that occurred from June 2000 to June 2015. The flares were selected homogeneously over the H[Formula: see text] and Geostationary Operational Environmental Satellite (GOES) classes, with an emphasis on including powerful confined flares and weak eruptive flares. H[Formula: see text] filtergrams from the Kanzelhöhe Observatory in combination with Michelson Doppler Imager (MDI) and Helioseismic and Magnetic Imager (HMI) magnetograms were used to derive the ribbon separation, the ribbon-separation velocity, the magnetic-field strength, and the reconnection electric field. We find that eruptive flares reveal statistically larger ribbon separation and higher ribbon-separation velocities than confined flares. In addition, the ribbon separation of eruptive flares correlates with the GOES SXR flux, whereas no clear dependence was found for confined flares. The maximum ribbon-separation velocity is not correlated with the GOES flux, but eruptive flares reveal on average a higher ribbon-separation velocity (by ≈ 10 km s-1). The local reconnection electric field of confined ([Formula: see text]) and eruptive ([Formula: see text]) flares correlates with the GOES flux, indicating that more powerful flares involve stronger reconnection electric fields. In addition, eruptive flares with higher electric-field strengths tend to be accompanied by faster coronal mass ejections. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11207-018-1253-1) contains supplementary material, which is available to authorized users.
RESUMEN
The fundi of 87 full-term newborns were repeatedly photographed from 2 to 144 h of life. At 2 h of life the width of the temporal arteries in the peripapillary area was about 100 micrometers and that of the nasal arteries about 70 micrometers, and all gradually decreased by about 30% during uneventful adaptation in room air. This decrease did not correlate with concomitant tcpO2 and blood pressure measurements. In most babies the arteries were slightly tortuous at 2 h of life and gradually straightened during adaptation. In some babies, however, there was marked tortuosity at 2 h of life, and this finding was significantly correlated with fetal risk factors. We conclude that marked tortuosity is a sign of passed acute fetal distress and that funduscopy in risk babies should be promoted.
