Optical photometry and spectra of the luminous type IIn supernova SN~2008iy are analysed in detail with implications for cosmic ray acceleration radio emission. The light curve expansion velocities indicate ejecta kinetic energy $3\times10^{51}$ erg to collide $\sim10$ Msun circumstellar envelope. Ha is explained as originated primarily from clouds interacting forward shock. For first time fluo...

Fifty-six resetting trials were conducted across the subjective day in 43 young men using a three-cycle bright-light (∼10,000 lx) stimulus against a background of very dim light (10-15 lx). The phase-response curve (PRC) to these trials was assessed for the presence of a "dead zone" of photic insensitivity and was compared with another three-cycle PRC that had used a background of ∼150 lx. To a...

In previous work we have presented evidence for electrogenic Na+/Ca2+ exchange in Limulus ventral photoreceptors (1989. J. Gen. Physiol. 93:473-492). This article assesses the contributions to photoreceptor physiology from Na+/Ca2+ exchange. Four separate physiological processes were considered: maintenance of resting sensitivity, light-induced excitation, light adaptation, and dark adaptation....

Normal human subjects were studied hourly by fluorophotometry to measure the normal circadian rhythm of aqueous humor flow. On a separate day, the subjects slept for approximately 1 hr after lunch; this short nap was not found to have any effect on aqueous flow. On a separate night, the subjects slept under a bright light of 2500 lux; the light was not found to have any effect on flow in the sl...