background and objective : irritable bowel syndrome (ibs) is a functional gastrointestinal disorder. sleep disturb-ances are known to be common among individuals with this syndrome. this study aimed to determine the relationship between sleep quality and severity of intestinal symptoms in irritable bowel syndrome. materials and methods : this cross-sectional study was carried out among 201 subj...

Extended periods of darkness have long been used to study how the mammalian visual system develops in the absence of any instruction from vision. Because of the relative ease of implementation of darkness as a means to eliminate visually driven neural activity, it has usually been imposed earlier in life and for much longer periods than was the case for other manipulations of the early visual i...

Buxton, Orfeu M., Mireille L’Hermite-Balériaux, Fred W. Turek, and Eve Van Cauter. Daytime naps in darkness phase shift the human circadian rhythms of melatonin and thyrotropin secretion. Am. J. Physiol. Regulatory Integrative Comp. Physiol. 278: R373–R382, 2000.—To systematically determine the effects of daytime exposure to sleep in darkness on human circadian phase, four groups of subjects pa...

The semidian ( approximately 12 h) periodicity in the effect of far-red (FR) interruptions of the light period preceding inductive darkness on flowering in Pharbitis nil appears to be mediated by phytochrome: (a) promotion by interruptions 2 hours before inductive darkness (-2 hours) and inhibition at -8 hours are greater the higher the proportion of FR/R+FR during the interruption; (b) brief F...

department of islamic philosophy and wisdom, university of zanjan the “mashriqiyya principle”, trusted by the persian theosophists and the basis for their light wisdom that suhrawardī tried to revive, is the principle of light and darkness. philosophy of illumination (ḥikmat ishrāq), as a discursive-intuitive philosophy, is a light-oriented metaphysical wisdom. in this wisdom, light is the secr...