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Author Kelber, A.; Balkenius, A.; Warrant, E.J. url  doi
openurl 
  Title Scotopic colour vision in nocturnal hawkmoths Type Journal Article
  Year 2002 Publication (down) Nature Abbreviated Journal Nature  
  Volume 419 Issue 6910 Pages 922-925  
  Keywords Animals; Behavior, Animal; Color; Color Perception/*physiology; Conditioning (Psychology)/physiology; Cues; *Darkness; Discrimination Learning/physiology; Humans; Light; Lighting; Moths/*physiology; Photic Stimulation; Photoreceptor Cells, Invertebrate/physiology; Reward; Sensitivity and Specificity; Ultraviolet Rays  
  Abstract Humans are colour-blind at night, and it has been assumed that this is true of all animals. But colour vision is as useful for discriminating objects at night as it is during the day. Here we show, through behavioural experiments, that the nocturnal hawkmoth Deilephila elpenor uses colour vision to discriminate coloured stimuli at intensities corresponding to dim starlight (0.0001 cd x m(-2)). It can do this even if the illumination colour changes, thereby showing colour constancy-a property of true colour vision systems. In identical conditions humans are completely colour-blind. Our calculations show that the possession of three photoreceptor classes reduces the absolute sensitivity of the eye, which indicates that colour vision has a high ecological relevance in nocturnal moths. In addition, the photoreceptors of a single ommatidium absorb too few photons for reliable discrimination, indicating that spatial and/or temporal summation must occur for colour vision to be possible. Taken together, our results show that colour vision occurs at nocturnal intensities in a biologically relevant context.  
  Address Department of Cell and Organism Biology, Vision Group, Lund University, Helgonavagen 3, S-22362 Lund, Sweden. almut.kelber@zool.lu.se  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-0836 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12410310 Approved no  
  Call Number LoNNe @ kagoburian @ Serial 606  
Permanent link to this record
 

 
Author Foster, R.G. url  doi
openurl 
  Title Neurobiology: bright blue times Type Journal Article
  Year 2005 Publication (down) Nature Abbreviated Journal Nature  
  Volume 433 Issue 7027 Pages 698-699  
  Keywords Human Health; Animals; Circadian Rhythm/physiology/radiation effects; Color Perception/physiology/*radiation effects; Humans; *Light; Light Signal Transduction/*radiation effects; Mice; Retinal Ganglion Cells/cytology/physiology/radiation effects; Retinaldehyde/chemistry/metabolism; Rod Opsins/*metabolism; NASA Discipline Space Human Factors; Non-NASA Center  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-0836 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15716938 Approved no  
  Call Number LoNNe @ kagoburian @ Serial 750  
Permanent link to this record
 

 
Author Meng, Y.; He, Z.; Yin, J.; Zhang, Y.; Zhang, T. url  doi
openurl 
  Title Quantitative calculation of human melatonin suppression induced by inappropriate light at night Type Journal Article
  Year 2011 Publication (down) Medical & Biological Engineering & Computing Abbreviated Journal Med Biol Eng Comput  
  Volume 49 Issue 9 Pages 1083-1088  
  Keywords Algorithms; Circadian Rhythm/physiology/*radiation effects; Humans; *Lighting; Melatonin/*secretion; *Models, Biological; Retinal Cone Photoreceptor Cells/physiology/radiation effects; Retinal Ganglion Cells/physiology/radiation effects; Retinal Rod Photoreceptor Cells/physiology/radiation effects  
  Abstract Melatonin (C(1)(3)H(1)(6)N(2)O(2)) has a wide range of functions in the body. When is inappropriately exposed to light at night, human circadian rhythm will be interfered and then melatonin secretion will become abnormal. For nearly three decades great progresses have been achieved in analytic action spectra and melatonin suppression by various light conditions. However, so far few articles focused on the quantitative calculation of melatonin suppression induced by light. In this article, an algorithm is established, in which all the contributions of rods, cones, and intrinsically photosensitive retinal ganglion cells are considered. Calculation results accords with the experimental data in references very well, which indicate the validity of this algorithm. This algorithm can also interpret the rule of melatonin suppression varying with light correlated color temperature very well.  
  Address Photonics Research Center, School of Physics, Nankai University, Tianjin 300071, China  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0140-0118 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:21717231 Approved no  
  Call Number IDA @ john @ Serial 236  
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Author Miler, M.; Sosic-Jurjevic, B.; Nestorovic, N.; Ristic, N.; Medigovic, I.; Savin, S.; Milosevic, V. url  doi
openurl 
  Title Morphological and functional changes in pituitary-thyroid axis following prolonged exposure of female rats to constant light Type Journal Article
  Year 2014 Publication (down) Journal of Morphology Abbreviated Journal J Morphol  
  Volume 275 Issue 10 Pages 1161-1172  
  Keywords TSH cells; constant light; immunohistochemistry; pituitary; rat; thyroid; light exposure  
  Abstract Light regulates numerous physiological functions and synchronizes them with the environment, in part by adjusting secretion of different hormones. We hypothesized that constant light (CL) would disturb pituitary-thyroid axis. Our aim was to determine morphological and functional changes in this endocrine system in such extreme conditions and, based on the obtained results, to propose the underlying mechanism(s). Starting from the thirtieth postnatal day, female Wistar rats were exposed to CL (600 lx) for the following 95 days. The controls were maintained under the regular laboratory lighting conditions. After decapitation, pituitaries and thyroids were prepared for further histomorphometric, immunohistochemical, and immunofluorescence examinations. Concentration of thyroid stimulating hormone (TSH), total T4 and T3 (TH) were determined. Thyroid tissue of light-treated rats was characterized by microfollicular structure. We detected no change in total thyroid volume, localization and accumulation of thyroglobulin, thyroid peroxidase, and sodium-iodide symporter in the follicular epithelium of CL rats. The volume of follicular epithelium and activation index were increased, while volume of the colloid and serum levels of TH decreased. In the pituitary, the relative intensity of TSH beta-immunofluorescence signal within the cytoplasm of thyrotrophs increased, but their average cell volume and the relative volume density decreased. Serum TSH was unaltered. We conclude that exposure of female rats to CL induced alterations in pituitary-thyroid axis. Thyroid tissue was characterized by microfollicular structure. Serum TH levels were reduced without accompanying increase in serum TSH. We hypothesize that increased secretion and clearance of TH together with unchanged or even decreased hormonal synthesis, resulted in decreased serum TH levels in CL group. We assume this decrease consequently led to increased synthesis and/or accumulation of pituitary TSH. However, decreased average TSH cell volume and relative volume density, together with unchanged serum TSH, point to additional, negative regulation of thyrotrophs. J. Morphol., 2014. (c) 2014 Wiley Periodicals, Inc.  
  Address Department of Cytology, Institute for Biological Research “Sinisa Stankovic,” University of Belgrade, Belgrade, Serbia  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-2887 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:24797691 Approved no  
  Call Number IDA @ john @ Serial 304  
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Author Brainard, G.C.; Sliney, D.; Hanifin, J.P.; Glickman, G.; Byrne, B.; Greeson, J.M.; Jasser, S.; Gerner, E.; Rollag, M.D. url  doi
openurl 
  Title Sensitivity of the human circadian system to short-wavelength (420-nm) light Type Journal Article
  Year 2008 Publication (down) Journal of Biological Rhythms Abbreviated Journal J Biol Rhythms  
  Volume 23 Issue 5 Pages 379-386  
  Keywords Human Health; Adult; Circadian Rhythm/*radiation effects; Female; Humans; *Light; Male; Melatonin/metabolism; Models, Biological; Neurosecretory Systems; Photons; Pineal Gland/metabolism; Retinal Ganglion Cells/*metabolism; Vision, Ocular  
  Abstract The circadian and neurobehavioral effects of light are primarily mediated by a retinal ganglion cell photoreceptor in the mammalian eye containing the photopigment melanopsin. Nine action spectrum studies using rodents, monkeys, and humans for these responses indicate peak sensitivities in the blue region of the visible spectrum ranging from 459 to 484 nm, with some disagreement in short-wavelength sensitivity of the spectrum. The aim of this work was to quantify the sensitivity of human volunteers to monochromatic 420-nm light for plasma melatonin suppression. Adult female (n=14) and male (n=12) subjects participated in 2 studies, each employing a within-subjects design. In a fluence-response study, subjects (n=8) were tested with 8 light irradiances at 420 nm ranging over a 4-log unit photon density range of 10(10) to 10(14) photons/cm(2)/sec and 1 dark exposure control night. In the other study, subjects (n=18) completed an experiment comparing melatonin suppression with equal photon doses (1.21 x 10(13) photons/cm(2)/sec) of 420 nm and 460 nm monochromatic light and a dark exposure control night. The first study demonstrated a clear fluence-response relationship between 420-nm light and melatonin suppression (p<0.001) with a half-saturation constant of 2.74 x 10(11) photons/cm(2)/sec. The second study showed that 460-nm light is significantly stronger than 420-nm light for suppressing melatonin (p<0.04). Together, the results clarify the visible short-wavelength sensitivity of the human melatonin suppression action spectrum. This basic physiological finding may be useful for optimizing lighting for therapeutic and other applications.  
  Address Department of Neurology, Thomas Jefferson University, Philadelphia, PA 19107, USA. george.brainard@jefferson.edu  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0748-7304 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:18838601 Approved no  
  Call Number LoNNe @ kagoburian @ Serial 724  
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