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Author (up) Bará, S.; Tilve, V.; Nievas, M.; Sanchez de Miguel, A.; Zamorano, J.
Title Zernike power spectra of clear and cloudy light-polluted urban night skies Type Journal Article
Year 2015 Publication Applied Optics Abbreviated Journal Appl. Opt.
Volume 54 Issue 13 Pages 4120-4129
Keywords Skyglow; artificial ligh at night; light pollution; Zernike; power spectrum; atmospheric optics; imaging systems; image analysis
Abstract The Zernike power spectra of the all-sky night brightness distributions of clear and cloudy nights are computed using a modal projection approach. The results obtained in the B, V and R Johnson-Cousins' photometric bands during a one-year campaign of observations at a light-polluted urban site show that these spectra can be described by simple power laws with exponents close to -3 for clear nights and -2 for cloudy ones. The second-moment matrices of the Zernike coefficients show relevant correlations between modes. The multiplicative role of the cloud cover, that contributes to a significant increase of the brightness of the urban night sky in comparison with the values obtained in clear nights, is described in the Zernike space.
Address Area de Optica, Dept. Fisica Aplicada. Facultade de Fisica / Facultade de Optica e Optometría Universidade de Santiago de Compostela Campus Sur, E-15782 Santiago de Compostela, Galicia, Spain; salva.bara@usc.es
Corporate Author Thesis
Publisher Optical Society of America Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1156
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Author (up) Gaston, K.J.; Visser, M.E.; Hölker, F.
Title The biological impacts of artificial light at night: the research challenge Type Journal Article
Year 2015 Publication Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences Abbreviated Journal Philos Trans R Soc Lond B Biol Sci
Volume 370 Issue Pages 20140133
Keywords Commentary; communities; dose-response; individuals; light spectrum; night-time
Abstract
Address 1 Environment and Sustainability Institute, University of Exeter, Penryn TR10 9FE, UK; k.j.gaston@exeter.ac.uk
Corporate Author Thesis
Publisher Royal Society Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title The biological impacts of artificial light at night: from molecules to communities Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1116
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Author (up) Ji, L.; Zhao, Z.; Zhu, X.; Yu, Y.; Shen, L.; Wang, L.
Title Harmful effects on organism induced by light of different wavelength and power Type Journal Article
Year 2014 Publication Optik Abbreviated Journal Optik
Volume 125 Issue 19 Pages 5808-5812
Keywords LED; Wavelength; Power; Microvessel; Absorption spectrum
Abstract Although a variety of experiments on light exposure stress to animals significantly affect the retina and circulation system, it is still unknown the relationship between the different extent of harmful effect on organism and light with different wavelengths and power. This study is aimed to investigate the changes to microblood vessel and the variations in serum absorption spectrum. LED light of different wavelength and power were used. The results show that power has a relatively larger impact on physiological indexes than wavelength. The extents of these variations are relatively different according to the regression equations. All of these stimulations cause damage to mice physiological conditions, producing some extent of light pollution. The research findings supply the guideline for the effective prevention of the harmful effect on organism by light pollution from the view of science of optical life science.
Address College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, People's Republic of China
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 362
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Author (up) Moore-Ede, M.; Heitmann, A.; Guttkuhn, R.
Title Circadian Potency Spectrum with Extended Exposure to Polychromatic White LED Light under Workplace Conditions Type Journal Article
Year 2020 Publication Journal of Biological Rhythms Abbreviated Journal J Biol Rhythms
Volume in press Issue Pages in press
Keywords Human Health; circadian; human; light spectrum; melatonin; spectral sensitivity
Abstract Electric light has enabled humans to conquer the night, but light exposure at night can disrupt the circadian timing system and is associated with a diverse range of health disorders. To provide adequate lighting for visual tasks without disrupting the human circadian timing system, a precise definition of circadian spectral sensitivity is required. Prior attempts to define the circadian spectral sensitivity curve have used short (</=90-min) monochromatic light exposures in dark-adapted human subjects or in vitro dark-adapted isolated retina or melanopsin. Several lines of evidence suggest that these dark-adapted circadian spectral sensitivity curves, in addition to 430- to 499-nm (blue) wavelength sensitivity, may include transient 400- to 429-nm (violet) and 500- to 560-nm (green) components mediated by cone- and rod-originated extrinsic inputs to intrinsically photosensitive retinal ganglion cells (ipRGCs), which decay over the first 2 h of extended light exposure. To test the hypothesis that the human circadian spectral sensitivity in light-adapted conditions may have a narrower, predominantly blue, sensitivity, we used 12-h continuous exposures of light-adapted healthy human subjects to 6 polychromatic white light-emitting diode (LED) light sources with diverse spectral power distributions at recommended workplace levels of illumination (540 lux) to determine their effect on the area under curve of the overnight (2000-0800 h) salivary melatonin. We derived a narrow steady-state human Circadian Potency spectral sensitivity curve with a peak at 477 nm and a full-width half-maximum of 438 to 493 nm. This light-adapted Circadian Potency spectral sensitivity permits the development of spectrally engineered LED light sources to minimize circadian disruption and address the health risks of light exposure at night in our 24/7 society, by alternating between daytime circadian stimulatory white light spectra and nocturnal circadian protective white light spectra.
Address Data Analytics Department, Circadian Technologies, Inc., Stoneham, Massachusetts
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 0748-7304 ISBN Medium
Area Expedition Conference
Notes PMID:32539484 Approved no
Call Number GFZ @ kyba @ Serial 3010
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Author (up) Rea, M. S.; Bierman, A.
Title Spectral considerations for outdoor lighting: Consequences for sky glow Type Journal Article
Year 2014 Publication Lighting Research and Technology Abbreviated Journal Lighting Res. & Tech.
Volume 47 Issue 8 Pages 920-930
Keywords Lighting; skyglow; spectrum; scattering; aerosol; modeling
Abstract It is well known that the magnitude of sky glow on a clear night depends upon the aerosol content in the atmosphere and the spectral power distribution (amount and spectrum). Sources with a greater proportion of short-wavelength radiation produce more backscattered radiation, but as aerosol density increases, the differential effect of spectrum becomes smaller. Sky glow magnitude also depends upon the operating characteristics of the detector and will be greater when the spectrum of the backscattered radiation is tuned to the spectral band-pass characteristics of the detector. The human visual system is most often used to assess sky glow magnitude, but its spectral response is not limited to a single, univariate detector. Rather, the retina is composed of many neural channels, each with its own spectral and absolute sensitivities to optical radiation. Since we can use a different neural channel to see an individual star than we do to gain an overall impression of sky brightness, changes to the spectral power distribution of backscattered radiation differentially, and simultaneously, affect one’s ability to see a single star and to assess sky brightness. A general method for assessing sky glow based upon aerosol content, spectral power distribution and the specific operating characteristics of a detector, human or otherwise, is offered.
Address Lighting Research Center, Rensselaer Polytechnic Institute, Troy, New York, USA
Corporate Author Thesis
Publisher The Society of Light and Lighting Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1065
Permanent link to this record