An intelligent agent for recognizing face under dim light conditions

Effects of forced sleep-wake schedules with and without physical exercise were examined on the human circadian pacemaker under dim light conditions. Subjects spent 15 days in an isolation facility separately without knowing the time of day and followed a forced sleep-wake schedule of a 23 h 40-min period for 12 cycles, and physical exercise was imposed twice per waking period for 2 h each with bicycle- or rowing-type ergometers. As a result, plasma melatonin rhythm was significantly phase advanced with physical exercise, whereas it was not changed without exercise. The difference in phase was already significant 6 days after the start of exercise. The amplitude of melatonin rhythm was not affected. A single pulse of physical exercise in the afternoon or at midnight significantly phase delayed the melatonin rhythms when compared with the prepulse phase, but the amount of phase shift was not different from that observed in the sedentary controls. These findings indicate that physical exercise accelerates phase-advance shifts of the human circadian pacemaker associated with the forced sleep-wake schedule.

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In situ measurements of photosynthetic irradiance responses of two Red Sea sponges growing under dim light conditions

Marine Biology ◽

10.1007/s002270050353 ◽

1998 ◽

Vol 131 (4) ◽

pp. 613-617 ◽

Cited By ~ 33

Author(s):

S. Beer ◽

M. Ilan

Keyword(s):

Red Sea ◽

In Situ Measurements ◽

Light Conditions ◽

Dim Light

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Subjective time runs faster under the influence of bright rather than dim light conditions during the forenoon

Physiology & Behavior ◽

10.1016/j.physbeh.2007.01.015 ◽

2007 ◽

Vol 91 (1) ◽

pp. 42-45 ◽

Cited By ~ 7

Author(s):

Takeshi Morita ◽

Tomoe Fukui ◽

Masayo Morofushi ◽

Hiromi Tokura

Keyword(s):

Subjective Time ◽

Light Conditions ◽

Dim Light

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Independent pseudogenization of CYP2J19 in penguins, owls and kiwis implicates gene in red carotenoid synthesis

10.1101/130468 ◽

2017 ◽

Author(s):

Christopher A. Emerling

Keyword(s):

Marked Reduction ◽

Bright Light ◽

Cytochrome P450 Enzyme ◽

Light Conditions ◽

Oil Droplets ◽

Sexual Signaling ◽

P450 Enzyme ◽

Show Evidence ◽

Carotenoid Synthesis ◽

Dim Light

AbstractCarotenoids have important roles in bird behavior, including pigmentation for sexual signaling and improving color vision via retinal oil droplets. Yellow carotenoids are diet-derived, but red carotenoids (ketocarotenoids) are typically synthesized from yellow precursors via a carotenoid ketolase. Recent research on passerines has provided evidence that a cytochrome p450 enzyme, CYP2J19, is responsible for this reaction, though it is unclear if this function is phylogenetically restricted. Here I provide evidence that CYP2J19 is the carotenoid ketolase common to Aves using the genomes of 65 birds and the retinal transcriptomes of 15 avian taxa. CYP2J19 is functionally intact and robustly transcribed in all taxa except for several species adapted to foraging in dim light conditions. Two penguins, an owl and a kiwi show evidence of genetic lesions and relaxed selection in their genomic copy of CYP2J19, and six owls show evidence of marked reduction in CYP2J19 retinal transcription compared to nine diurnal avian taxa. Notably, none of these taxa are known to use red carotenoids for sexual signaling and several species of owls and penguins represent the only birds known to completely lack red retinal oil droplets. The remaining avian taxa belong to groups known to possess red oil droplets, known or expected to deposit red carotenoids in skin and/or plumage, and/or frequently forage in bright light. The loss and reduced expression of CYP2J19 is likely an adaptation to maximize retinal sensitivity, given that oil droplets reduce the amount of light available to the retina.

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Reading performance of monofocal pseudophakic patients with and without glasses under normal and dim light conditions

Journal of Cataract & Refractive Surgery ◽

10.1016/j.jcrs.2013.08.054 ◽

2014 ◽

Vol 40 (3) ◽

pp. 369-375 ◽

Cited By ~ 14

Author(s):

Wolfgang Radner ◽

Stephan Radner ◽

Valerian Raunig ◽

Gabriela Diendorfer

Keyword(s):

Reading Performance ◽

Light Conditions ◽

Dim Light

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Demonstration of rapid light-induced advances and delays of the human circadian clock using hormonal phase markers

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1994.266.6.e953 ◽

1994 ◽

Vol 266 (6) ◽

pp. E953-E963 ◽

Cited By ~ 24

Author(s):

E. Van Cauter ◽

J. Sturis ◽

M. M. Byrne ◽

J. D. Blackman ◽

R. Leproult ◽

...

Keyword(s):

Circadian Clock ◽

Light Pulse ◽

Light Exposure ◽

Bright Light ◽

Phase Shifts ◽

Light Conditions ◽

Single Exposure ◽

Dim Light ◽

Nocturnal Period

To determine the magnitude and direction of phase shifts of human circadian rhythms occurring within 1 day after a single exposure to bright light, plasma thyrotropin, melatonin, and cortisol levels and body temperature were monitored for 38 h in 17 men who were each studied two times, once during continuous dim light conditions and once with light exposure. After a period of entrainment to a fixed sleep-wake cycle, a 3-h light pulse (5,000 lux) was presented under constant routine conditions, and the resultant phase shifts were measured, also under constant routine conditions, on the 1st day after pulse presentation. The phase shifts in response to light occurred within 24 h and were in the delaying direction for most of the nocturnal period, with the crossover to phase advances occurring approximately 1 h after the temperature minimum. Phase shifts averaged 1 h, with delays being larger than advances, and were achieved without significant changes in rhythm amplitude. The immediate response of the human circadian clock to a single 3-h light pulse is thus characteristic of "type 1" resetting.

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