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Author Aubé, M.; Roby, J.; Kocifaj, M.
Title Evaluating potential spectral impacts of various artificial lights on melatonin suppression, photosynthesis, and star visibility Type Journal Article
Year 2013 Publication PloS one Abbreviated Journal (down) PLoS One
Volume 8 Issue 7 Pages e67798
Keywords Humans; *Light; Lighting/methods; Melatonin/*metabolism; Photosynthesis/*radiation effects; Plant Development/radiation effects; blue light; circadian disruption
Abstract Artificial light at night can be harmful to the environment, and interferes with fauna and flora, star visibility, and human health. To estimate the relative impact of a lighting device, its radiant power, angular photometry and detailed spectral power distribution have to be considered. In this paper we focus on the spectral power distribution. While specific spectral characteristics can be considered harmful during the night, they can be considered advantageous during the day. As an example, while blue-rich Metal Halide lamps can be problematic for human health, star visibility and vegetation photosynthesis during the night, they can be highly appropriate during the day for plant growth and light therapy. In this paper we propose three new indices to characterize lamp spectra. These indices have been designed to allow a quick estimation of the potential impact of a lamp spectrum on melatonin suppression, photosynthesis, and star visibility. We used these new indices to compare various lighting technologies objectively. We also considered the transformation of such indices according to the propagation of light into the atmosphere as a function of distance to the observer. Among other results, we found that low pressure sodium, phosphor-converted amber light emitting diodes (LED) and LED 2700 K lamps filtered with the new Ledtech's Equilib filter showed a lower or equivalent potential impact on melatonin suppression and star visibility in comparison to high pressure sodium lamps. Low pressure sodium, LED 5000 K-filtered and LED 2700 K-filtered lamps had a lower impact on photosynthesis than did high pressure sodium lamps. Finally, we propose these indices as new standards for the lighting industry to be used in characterizing their lighting technologies. We hope that their use will favor the design of new environmentally and health-friendly lighting technologies.
Address Departement de physique, Cegep de Sherbrooke, Sherbrooke, Quebec, Canada. martin.aube@cegepsherbrooke.qc.ca
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 1932-6203 ISBN Medium
Area Expedition Conference
Notes PMID:23861808; PMCID:PMC3702543 Approved no
Call Number IDA @ john @ Serial 282
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Author Solano Lamphar, H.A.; Kocifaj, M.
Title Light pollution in ultraviolet and visible spectrum: effect on different visual perceptions Type Journal Article
Year 2013 Publication PloS one Abbreviated Journal (down) PLoS One
Volume 8 Issue 2 Pages e56563
Keywords Lighting; Animals; *Environmental Pollution; Humans; Insects; Light; Lighting/*adverse effects; Models, Theoretical; *Visual Perception
Abstract In general terms, lighting research has been focused in the development of artificial light with the purpose of saving energy and having more durable lamps. However, the consequences that artificial night lighting could bring to the human being and living organisms have become an important issue recently. Light pollution represents a significant problem to both the environment and human health causing a disruption of biological rhythms related not only to the visible spectrum, but also to other parts of the electromagnetic spectrum. Since the lamps emit across a wide range of the electromagnetic spectrum, all photobiological species may be exposed to another type of light pollution. By comparing five different lamps, the present study attempts to evaluate UV radiative fluxes relative to what humans and two species of insects perceive as sky glow level. We have analyzed three atmospheric situations: clear sky, overcast sky and evolving precipitable water content. One important finding suggests that when a constant illuminance of urban spaces has to be guaranteed the sky glow from the low pressure sodium lamps has the most significant effect to the visual perception of the insects tested. But having the fixed number of luminaires the situation changes and the low pressure sodium lamp would be the best choice for all three species. The sky glow effects can be interpreted correctly only if the lamp types and the required amount of scotopic luxes at the ground are taken into account simultaneously. If these two factors are combined properly, then the ecological consequences of sky glow can be partly reduced. The results of this research may be equally useful for lighting engineers, architects, biologists and researchers who are studying the effects of sky glow on humans and biodiversity.
Address ICA, Slovak Academy of Sciences, Bratislava, Slovak Republic. lamphar@gmail.com
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 1932-6203 ISBN Medium
Area Expedition Conference
Notes PMID:23441205; PMCID:PMC3575508 Approved no
Call Number LoNNe @ schroer @ Serial 578
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Author Ciocca, M.; Wang, J.
Title By the light of the silvery Moon: fact and fiction Type Journal Article
Year 2013 Publication Physics Education Abbreviated Journal (down) Phys. Educ.
Volume 48 Issue 3 Pages 360-367
Keywords Vision; moonlight; Purkinje effect; Purkinje shift; mesopic
Abstract Is moonlight 'silver' or 'cold'? In this paper we discuss the interesting combination of factors that contribute to the common descriptions of moonlight. Sunlight is reflected from the lunar surface and red-shifted. When traversing the atmosphere, moonlight is further depleted of short wavelength content by Rayleigh scattering. We measured the spectra of the moonlight to show these effects and compared them with sunlight. All measurements, including spectral reflectance, suggest that moonlight is redder than sunlight. The silvery Moon is just an illusion due to the properties and behaviour of our own eyes, including the responses of rods and cones and the physiological perceptive phenomenon called Purkinje shift.
Address Eastern Kentucky University, Richmond, KY, USA E-mail: marco.ciocca(at)eku.edu
Corporate Author Thesis
Publisher IOP Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9120 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 2227
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Author Chamorro, E.; Bonnin-Arias, C.; Perez-Carrasco, M.J.; Munoz de Luna, J.; Vazquez, D.; Sanchez-Ramos, C.
Title Effects of light-emitting diode radiations on human retinal pigment epithelial cells in vitro Type Journal Article
Year 2013 Publication Photochemistry and Photobiology Abbreviated Journal (down) Photochem Photobiol
Volume 89 Issue 2 Pages 468-473
Keywords Human Health; Apoptosis/*radiation effects; Biological Markers/metabolism; Caspases/metabolism; Cell Survival/radiation effects; DNA Damage; Epithelial Cells/cytology/metabolism/*radiation effects; Histones/metabolism; Humans; Light; Membrane Potential, Mitochondrial/*radiation effects; Mitochondria/*radiation effects; Photoperiod; Primary Cell Culture; Reactive Oxygen Species/metabolism; Retinal Pigment Epithelium/cytology/metabolism/*radiation effects
Abstract Human visual system is exposed to high levels of natural and artificial lights of different spectra and intensities along lifetime. Light-emitting diodes (LEDs) are the basic lighting components in screens of PCs, phones and TV sets; hence it is so important to know the implications of LED radiations on the human visual system. The aim of this study was to investigate the effect of LEDs radiations on human retinal pigment epithelial cells (HRPEpiC). They were exposed to three light-darkness (12 h/12 h) cycles, using blue-468 nm, green-525 nm, red-616 nm and white light. Cellular viability of HRPEpiC was evaluated by labeling all nuclei with DAPI; Production of reactive oxygen species (ROS) was determined by H2DCFDA staining; mitochondrial membrane potential was quantified by TMRM staining; DNA damage was determined by H2AX histone activation, and apoptosis was evaluated by caspases-3,-7 activation. It is shown that LED radiations decrease 75-99% cellular viability, and increase 66-89% cellular apoptosis. They also increase ROS production and DNA damage. Fluorescence intensity of apoptosis was 3.7% in nonirradiated cells and 88.8%, 86.1%, 83.9% and 65.5% in cells exposed to white, blue, green or red light, respectively. This study indicates three light-darkness (12 h/12 h) cycles of exposure to LED lighting affect in vitro HRPEpiC.
Address Neuro-Computing and Neuro-Robotics Research Group, Universidad Complutense de Madrid, Madrid, Spain. eva.chamorro@opt.ucm.es
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 0031-8655 ISBN Medium
Area Expedition Conference
Notes PMID:22989198 Approved no
Call Number LoNNe @ christopher.kyba @ Serial 511
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Author Forbes, C.; Hammill, E.
Title Fear in the dark? Community-level effects of non-lethal predators change with light regime Type Journal Article
Year 2013 Publication Oikos Abbreviated Journal (down) Oikos
Volume 122 Issue 12 Pages 1662-1668
Keywords Animals
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0030-1299 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ kagoburian @ Serial 597
Permanent link to this record