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Author Galadí-Enríquez, D.
Title Beyond CCT: The spectral index system as a tool for the objective, quantitative characterization of lamps Type Journal Article
Year 2018 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal JQSRT
Volume 206 Issue Pages 399-408
Keywords Lighting
Abstract Correlated color temperature (CCT) is a semi-quantitative system that roughly describes the spectra of lamps. This parameter gives the temperature (measured in kelvins) of the black body that would show the hue more similar to that of the light emitted by the lamp. Modern lamps for indoor and outdoor lighting display many spectral energy distributions, most of them extremely different to those of black bodies, what makes CCT to be far from a perfect descriptor from the physical point of view. The spectral index system presented in this work provides an accurate, objective, quantitative procedure to characterize the spectral properties of lamps, with just a few numbers. The system is an adaptation to lighting technology of the classical procedures of multi-band astronomical photometry with wide and intermediate-band filters. We describe the basic concepts and we apply the system to a representative set of lamps of many kinds. The results lead to interesting, sometimes surprising conclusions. The spectral index system is extremely easy to implement from the spectral data that are routinely measured at laboratories. Thus, including this kind of computations in the standard protocols for the certification of lamps will be really straightforward, and will enrich the technical description of lighting devices.
Address
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language (up) English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4073 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 1835
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Author Hoffmann, J.; Palme, R.; Eccard, J.A.
Title Long-term dim light during nighttime changes activity patterns and space use in experimental small mammal populations Type Journal Article
Year 2018 Publication Environmental Pollution Abbreviated Journal Environ Pollut
Volume 238 Issue Pages 844-851
Keywords Animals
Abstract Artificial light at night (ALAN) is spreading worldwide and thereby is increasingly interfering with natural dark-light cycles. Meanwhile, effects of very low intensities of light pollution on animals have rarely been investigated. We explored the effects of low intensity ALAN over seven months in eight experimental bank vole (Myodes glareolus) populations in large grassland enclosures over winter and early breeding season, using LED garden lamps. Initial populations consisted of eight individuals (32 animals per hectare) in enclosures with or without ALAN. We found that bank voles under ALAN experienced changes in daily activity patterns and space use behavior, measured by automated radiotelemetry. There were no differences in survival and body mass, measured with live trapping, and none in levels of fecal glucocorticoid metabolites. Voles in the ALAN treatment showed higher activity at night during half moon, and had larger day ranges during new moon. Thus, even low levels of light pollution as experienced in remote areas or by sky glow can lead to changes in animal behavior and could have consequences for species interactions.
Address Animal Ecology, University of Potsdam, Maulbeerallee 1, 14469, Potsdam, Germany
Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0269-7491 ISBN Medium
Area Expedition Conference
Notes PMID:29627754 Approved no
Call Number GFZ @ kyba @ Serial 1848
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Author Linden, B.; Huisman, J.; Rinkevich, B.
Title Circatrigintan instead of lunar periodicity of larval release in a brooding coral species Type Journal Article
Year 2018 Publication Scientific Reports Abbreviated Journal Sci Rep
Volume 8 Issue 1 Pages 5668
Keywords Animals
Abstract Larval release by brooding corals is often assumed to display lunar periodicity. Here, we show that larval release of individual Stylophora pistillata colonies does not comply with the assumed tight entrainment by the lunar cycle, and can better be classified as a circatrigintan pattern. The colonies exhibited three distinct reproductive patterns, characterized by short intervals, long intervals and no periodicity between reproductive peaks, respectively. Cross correlation between the lunar cycle and larval release of the periodic colonies revealed an approximately 30-day periodicity with a variable lag of 5 to 10 days after full moon. The observed variability indicates that the lunar cycle does not provide a strict zeitgeber. Other factors such as water temperature and solar radiation did not correlate significantly with the larval release. The circatrigintan patterns displayed by S. pistillata supports the plasticity of corals and sheds new light on discussions on the fecundity of brooding coral species.
Address Israel Oceanographic and Limnological Research, National Institute of Oceanography, Tel-Shikmona, P.O. Box 8030, Haifa, 31080, Israel
Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Medium
Area Expedition Conference
Notes PMID:29618779 Approved no
Call Number GFZ @ kyba @ Serial 1849
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Author Scheuermaier, K.; Munch, M.; Ronda, J.M.; Duffy, J.F.
Title Improved cognitive morning performance in healthy older adults following blue-enriched light exposure on the previous evening Type Journal Article
Year 2018 Publication Behavioural Brain Research Abbreviated Journal Behav Brain Res
Volume 348 Issue Pages 267-275
Keywords Human Health
Abstract OBJECTIVES: Exposure to light can have acute alerting and circadian phase-shifting effects. This study investigated the effects of evening exposure to blue-enriched polychromatic white (BEL) vs. polychromatic white light (WL) on sleep inertia dissipation the following morning in older adults. METHODS: Ten healthy older adults (average age=63.3 yrs; 6F) participated in a 13-day study comprising three baseline days, an initial circadian phase assessment, four days with 2-h evening light exposures, a post light exposure circadian phase assessment and three recovery days. Participants were randomized to either BEL or WL of the same irradiance for the four evening light exposures. On the next mornings at 2, 12, 22 and 32min after each wake time, the participants completed a 90-s digit-symbol substitution test (DSST) to assess working memory, and objective alertness was assessed using a wake EEG recording. DSST and power density from the wake EEG recordings were compared between the two groups. RESULTS: DSST performance improved with time awake (p<0.0001) and across study days in both light exposure groups (p<0.0001). There was no main effect of group, although we observed a significant day x group interaction (p=0.0004), whereby participants exposed to BEL performed significantly better on the first two mornings after light exposures than participants in WL (post-hoc, p<0.05). On those days, the BEL group showed higher EEG activity in some of the frequency bins in the sigma and beta range (p<0.05) on the wake EEG. CONCLUSION: Exposure to blue-enriched white light in the evening significantly improved DSST performance the following morning when compared to polychromatic white light. This was associated with a higher level of objective alertness on the wake EEG, but not with changes in sleep or circadian timing.
Address Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, United States; Division of Sleep Medicine, Harvard Medical School, Boston, MA, United States
Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0166-4328 ISBN Medium
Area Expedition Conference
Notes PMID:29684473 Approved no
Call Number GFZ @ kyba @ Serial 1899
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Author Solano-Lamphar, H.A.; Kocifaj, M.
Title Numerical research on the effects the skyglow could have in phytochromes and RQE photoreceptors of plants Type Journal Article
Year 2018 Publication Journal of Environmental Management Abbreviated Journal J Environ Manage
Volume 209 Issue Pages 484-494
Keywords Plants; Skyglow
Abstract The increase of artificial light at night has a terrible impact on organisms with nightlife patterns such as a migration, nutrition, reproduction and collective interaction. Plants are not free from this issue as they have life cycle events occurring not only yearly but also daily. Such events relate to daytime variations with seasons in which the flowers of deciduous trees bloom and the leaves of certain trees fall off and change color. A response of plants to artificial light at night still remains poorly quantified; but recent scientific research suggest that skyglow can disturb plants processes. For instance, low levels of light affect deciduous plants, which shed their leaves as days grow short in the fall. In this paper we model skyglow considering the features of artificial light that can affect natural processes of plants during the night. A case-study was conducted to mimic skyglow effects in real location for which experimental data exist. In our numerical simulations we found that some lighting systems can have an effect on plant photoreceptors and affect the phenology of plants. Specifically, the lamps that emit the electromagnetic energy in a wide spectral range can have greater effect on the photosensitivity of the plants. We believe the results obtained here will motivate botanists to make a targeted experiment to verify or challenge our findings. If the night light can change plant behavior under some conditions, it can have significant implications in botany, biology, or even agriculture.
Address ICA, Slovak Academy of Sciences, Dubravska Road 9, 845 03, Bratislava, Slovak Republic; Faculty of Mathematics, Physics, and Informatics, Comenius University, Mlynska Dolina, 842 48, Bratislava, Slovakia. Electronic address: kocifaj@savba.sk
Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0301-4797 ISBN Medium
Area Expedition Conference
Notes PMID:29316469 Approved no
Call Number GFZ @ kyba @ Serial 1854
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