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Author (down) Spitschan, M.; Cajochen, C.
Title Binocular facilitation in light-mediated melatonin suppression? Type Journal Article
Year 2019 Publication Journal of Pineal Research Abbreviated Journal J Pineal Res
Volume 67 Issue 4 Pages e12602
Keywords Human Health; Vision; melatonin suppression; monocular; binocular
Abstract Astronomers and pilots have known for a long time that closing one eye can preserve vision in that eye while going from dark to light and back. Recently, it was reported that viewing a smartphone monocularly in an otherwise dark room can lead to transient, but strong reductions in retinal sensitivity in that eye (Alim-Marvasti, Bi, Mahroo, Barbur, & Plant, 2016). But seeing detail is not the only function that is mediated by the retina. Here, we address the question whether light exposure to one eye only (monocular) has tangible effects on the suppression of melatonin by light, relative to both eyes open (binocular).
Address Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland
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 0742-3098 ISBN Medium
Area Expedition Conference
Notes PMID:31361918 Approved no
Call Number GFZ @ kyba @ Serial 2595
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Author (down) Souman, J.L.; Tinga, A.M.; Te Pas, S.F.; van Ee, R.; Vlaskamp, B.N.S.
Title Acute alerting effects of light: a systematic literature review Type Journal Article
Year 2018 Publication Behavioural Brain Research Abbreviated Journal Behav Brain Res
Volume 337 Issue Pages 228-239
Keywords Human Health
Abstract Periodic, well timed exposure to light is important for our health and wellbeing. Light, in particular in the blue part of the spectrum, is thought to affect alertness both indirectly, by modifying circadian rhythms, and directly, giving rise to acute effects. We performed a systematic review of empirical studies on direct, acute effects of light on alertness to evaluate the reliability of these effects and to assess to what extent they depend on other factors, such as time of day, exposure duration and sleep pressure. In total, we identified 74 studies in which either light intensity, spectral distribution, or both were manipulated, and the effects on behavioral measures of alertness were evaluated, either subjectively or measured in performance tasks. The results show that increasing the intensity or the color temperature of polychromatic white light in general has been found to increase subjective ratings of alertness, though a substantial proportion of these studies failed to find significant effects. There is little evidence in the literature that these subjective alerting effects of light also translate into improvements on performance measures of alertness. For monochromatic or narrowband light exposure, some studies have shown improvement in reaction time tasks with exposure to blue light, but generally this was not accompanied by changes in subjective alertness. Thus, the alerting effects of light are far less clear than often suggested. We suggest that in future studies more attention should be paid to other factors that may influence the effects of light, such as chronotype, circadian phase, homeostatic state and prior light history.
Address Philips Research (Department Brain, Behavior & Cognition), Eindhoven, The Netherlands
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 0166-4328 ISBN Medium
Area Expedition Conference
Notes PMID:28912014 Approved no
Call Number LoNNe @ kyba @ Serial 1727
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Author (down) Song, J.; Tong, X.; Wang, L.; Zhao, C.; Prishchepov, A.V.
Title Monitoring finer-scale population density in urban functional zones: A remote sensing data fusion approach Type Journal Article
Year 2019 Publication Landscape and Urban Planning Abbreviated Journal Landscape and Urban Planning
Volume 190 Issue Pages 103580
Keywords Remote Sensing; nighttime light; numerical methods
Abstract Spatial distribution information on population density is essential for understanding urban dynamics. In recent decades, remote sensing techniques have often been applied to assess population density, particularly night-time light data (NTL). However, such attempts have resulted in mapped population density at coarse/medium resolution, which often limits the applicability of such data for fine-scale territorial planning. The improved quality and availability of multi-source remote sensing imagery and location-based service data (LBS) (from mobile networks or social media) offers new potential for providing more accurate population information at the micro-scale level. In this paper, we developed a fine-scale population distribution mapping approach by combining the functional zones (FZ) mapped with high-resolution satellite images, NTL data, and LBS data. Considering the possible variations in the relationship between population distribution and nightlight brightness in functional zones, we tested and found spatial heterogeneity of the relationship between NTL and the population density of LBS samples. Geographically weighted regression (GWR) was thus implemented to test potential improvements to the mapping accuracy. The performance of the following four models was evaluated: only ordinary least squares regression (OLS), only GWR, OLS with functional zones (OLS&FZ) and GWR with functional zones (GWR&FZ). The results showed that NTL-based GWR&FZ was the most accurate and robust approach, with an accuracy of 0.71, while the mapped population density was at a unit of 30 m spatial resolution. The detailed population density maps developed in our approach can contribute to fine-scale urban planning, healthcare and emergency responses in many parts of the world.
Address Department of Geosciences and Natural Resource Management, University of Copenhagen, 1350 Copenhagen, Denmark; songjinchao08(at)163.com
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0169-2046 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2516
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Author (down) Solbrig, J.E.; Miller, S.D.; Zhang, J.; Grasso, L.; Kliewer, A.
Title Assessing the stability of surface lights for use in retrievals of nocturnal atmospheric parameters Type Journal Article
Year 2020 Publication Atmospheric Measurement Techniques Abbreviated Journal Atmos. Meas. Tech.
Volume 13 Issue 1 Pages 165-190
Keywords Remote Sensing
Abstract The detection and characterization of aerosols are inherently limited at night because the important information provided by visible spectrum observations is not available and infrared bands have limited sensitivity to aerosols. The VIIRS Day–Night Band (DNB) onboard the Suomi-NPP satellite is a first-of-its-kind calibrated sensor capable of collecting visible and near-infrared observations during both day and night. Multiple studies have suggested that anthropogenic light emissions such as those from cities and gas flares may be useable as light sources for the retrieval of atmospheric properties, including cloud and aerosol optical depth. However, their use in this capacity requires proper characterization of their intrinsic variation, which represents a source of retrieval uncertainty. In this study we use 18 months of cloud-cleared VIIRS data collected over five selected geographic domains to assess the stability of anthropogenic light emissions and their response to varied satellite and lunar geometries. Time series are developed for each location in each domain for DNB radiance, four infrared channels, and satellite and lunar geometric variables, and spatially resolved correlation coefficients are computed between DNB radiance and each of the other variables. This analysis finds that while many emissive light sources are too unstable to be used reliably for atmospheric retrievals, some sources exhibit a sufficient stability (relative standard deviation <20 %). Additionally, we find that while the radiance variability of surrounding surfaces (i.e., unpopulated land and ocean) is largely dependent on lunar geometry, the anthropogenic light sources are more strongly correlated with satellite viewing geometry. Understanding the spatially resolved relationships between DNB radiance and other parameters is a necessary first step towards characterizing anthropogenic light emissions and establishes a framework for a model to describe variability in a more general sense.
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 1867-8548 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 3005
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Author (down) Solano Lamphar, H.A.; Kocifaj, M.
Title Urban night-sky luminance due to different cloud types: A numerical experiment Type Journal Article
Year 2015 Publication Lighting Research and Technology Abbreviated Journal Lighting Res. & Tech.
Volume 48 Issue 8 Pages 1017-1033
Keywords Skyglow; modeling; urban; clouds; radiative transfer
Abstract In this paper, we analyse theoretically and numerically the sky glow in urban and suburban areas, focusing on the zenith-normalised luminance of a cloudy sky. The results suggest that the altitude of a cloud imposes important changes in the luminance distribution. Peak values of sky luminance can be observed at a distance d = R + h tan (z), where R is the city radius, and h is the cloud altitude. Fluctuations of the zenith-normalised luminance over the city are dictated by three effects, specifically (i) extinction and backscatter in the undercloud atmosphere, (ii) the cloud properties and (iii) the radiant intensity function of the dominant ground-based light sources. For high clouds, the aerosol optical property is evident at moderate elevation angles. The light beams emitted from different parts of the city propagate along different inclined trajectories before they contribute to the elevated zenith luminance of low clouds. Then, multiple factors combine together to form the light field at the ground, city-size and city emission pattern being of specific importance.
Address Cátedras CONACYT, Instituto de investigaciones Dr José María Luis Mora, Programa Interdisciplinario de Estudios Metropolitanos (CentroMet), Plaza Valentín Gómez Farías #12 Col. San Juan Mixcoac, México D.F. C.P 03730. E-mail: lamphar(at)gmail.com
Corporate Author Thesis
Publisher SAGE Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1477-0938 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1225
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