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Author Huss, A.; van Wel, L.; Bogaards, L.; Vrijkotte, T.; Wolf, L.; Hoek, G.; Vermeulen, R.
Title Shedding Some Light in the Dark-A Comparison of Personal Measurements with Satellite-Based Estimates of Exposure to Light at Night among Children in the Netherlands Type Journal Article
Year 2019 Publication Environmental Health Perspectives Abbreviated Journal Environ Health Perspect
Volume 127 Issue 6 Pages (down) 67001
Keywords Human Health; Remote Sensing
Abstract BACKGROUND: Exposure to light at night (LAN) can perturb the biological clock and affect sleep and health. Previous epidemiological studies have evaluated LAN levels measured by satellites, but the validity of this measure as a proxy for personal LAN exposure is unclear. In addition, outdoor satellite-measured LAN levels are higher in urban environments, which means that this measure could potentially represent a proxy for other, likely urban, environmental exposures. OBJECTIVES: We evaluated correlations of satellite-assessed LAN with measured bedroom light levels and explored correlations with other environmental exposures, in particular, air pollution, green space, and area-level socioeconomic position (SEP). METHODS: We compared satellite measurements with evening and nighttime bedroom measurements of illuminance (in units of lux) for 256 children, and we evaluated correlations between satellite-based measures and other urban exposures such as air pollution, area-level SEP, and surrounding green space for 3,021 children. RESULTS: Satellite-measured LAN levels (nanowatts per centimeter squared per steradian) were not correlated with measured evening or nighttime lux levels [Spearman correlation coefficients ([Formula: see text]) [Formula: see text] to 0.04]. There was a weak correlation with measurements during the darkest time period if parents and their children reported that outdoor light sometimes or usually influenced indoor light levels ([Formula: see text], [Formula: see text]). In contrast, satellite-measured LAN levels were correlated with air pollution ([Formula: see text] with [Formula: see text], [Formula: see text] with [Formula: see text]), and surrounding green space ([Formula: see text] for green space within [Formula: see text] of the home). A weak correlation with area-level SEP was also observed ([Formula: see text]). CONCLUSIONS: Outdoor satellite-assessed outdoor LAN exposure levels were correlated with urban environmental exposures, but they were not a good proxy for indoor evening or nighttime personal exposure as measured in our study population of 12-y-old children. Studies planning to evaluate potential risks from LAN should consider such modifying factors as curtains and indoor lighting and the use of electronic devices and should include performing indoor or personal measurements to validate any exposure proxies. The moderate-to-strong correlation of outdoor LAN with other environmental exposures should be accounted for in epidemiological investigations. https://doi.org/10.1289/EHP3431.
Address 4 Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht , Utrecht, Netherlands
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 0091-6765 ISBN Medium
Area Expedition Conference
Notes PMID:31157976 Approved no
Call Number GFZ @ kyba @ Serial 2532
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Author Kim, H.-S.; Lee, Y.H.
Title Correlation Analysis of Image Reproduction and Display Color Temperature Change to Prevent Sleep Disorder Type Journal Article
Year 2019 Publication IEEE Access Abbreviated Journal IEEE Access
Volume 7 Issue Pages (down) 59091-59099
Keywords Human Health
Abstract This paper aims to determine the effect of the smartphone warm color temperature functionthat relieves display’s HEVL (high-energy visible light and short wavelength series blue light), which isknown to cause suppression of melatonin secretion on actual image reproduction quality. For this study,the author of this paper measured the display based on the color difference in 26 sampling colors. It was foundthat for correlated color temperature (CCT) of 4000 K or less, the color difference rose sharply, centeringaround red and green. In hardware or software, a low CCT was realized by reducing the output centered onblue and green, but in actual color quality, a problem arose in the red and green channels. As far as tonegradation is concerned,1E increased for CCT of 4500 K or less while the accuracy of the shadow detail wasreduced. With regard to color gamut reproduction, for the coverage of sRGB color space, the color gamutbecame narrow for CCT of 5500 K or less, and for volume, the color gamut became narrow sharply for CCTof 4000 K. It was found that the maximum CCT changes to prevent a decline in melatonin secretion at alevel of minimizing the degradation of image quality is 4000–4500 K.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2169-3536 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2500
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Author Wang, X.; Cheng, H.
Title Study on the Temporal and Spatial Pattern Differences of Chinese Light Curl Based on DMSP/OLS Type Journal Article
Year 2019 Publication IOP Conference Series: Earth and Environmental Science Abbreviated Journal IOP Conf. Ser.: Earth Environ. Sci.
Volume 310 Issue Pages (down) 032072
Keywords Remote Sensing
Abstract Nighttime light data can detect surface gleams that can intuitively reflect human socioeconomic activity.This paper uses the DMSP/OLS nighttime lighting data from 2001 to 2007 to analyze the coupling relationship between regional economic development and nighttime light intensity in China using regression model.The results show that the brightest areas of nighttime light are mainly concentrated in the Beijing-Tianjin-Hebei region, the Yangtze River Delta region, and the Pearl River Delta region. With the change of theyear, the brightness of the three regions is brighter year by year, indicating that the economy is more and more developed.The linear regression model of total brightness and GDP of regional light: Y=792.218+0.024X, linear slope is 0.024, indicating a positive correlation trend.The provinces and cities with the highest total brightness of the provinces and cities are Guangdong Province, Shandong Province, and Jiangsu Province, and the lowest provinces and cities are Qinghai Province and Tibet Autonomous Region.The total brightness of regional lights in China's provinces and cities is well coupled with GDP. The total brightness of regional lights in all provinces and cities is weakened from east to west. The brightness of the 11 provinces in the eastern region is the strongest, including Beijing, Tianjin, Hebei, Liaoning, Shanghai, and Jiangsu, Zhejiang, Fujian, Shandong, Guangdong, Hainan Province.The second most powerful lighting is the eight provinces in the central region including Shanxi, Jilin, Heilongjiang, Anhui, Jiangxi, Henan, Hubei, and Hunan.The weakest lighting is in the western regions of Sichuan, Chongqing, Guizhou, Yunnan, Tibet, Shaanxi, Gansu, Qinghai, Ningxia, Xinjiang, Guangxi, Inner Mongolia and other provinces (cities).In the east of the Hu Huanyong line, the nighttime lighting is higher than the west of the Hu Huanyong line.The eastern part of China's seven geographical divisions (Shanghai, Jiangsu, Zhejiang, Anhui, Jiangxi, Shandong, Fujian, and Taiwan) has the brightest night lights.The northwestern region (Shaanxi, Gansu, Qinghai, Ningxia Hui Autonomous Region, Xinjiang Uygur Autonomous Region, and Inner Mongolia Autonomous Region) has a weak night light.The brightness information of nighttime remote sensing data selected in this study can reflect the level of regional economic development.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1755-1315 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2670
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Author Burggraaff, O., Schmidt, N., Zamorano, J., Pauly, K., Pascual, S., Tapia, C., Spyrakos, E., & Snik, F.
Title Standardized spectral and radiometric calibration of consumer cameras Type Journal Article
Year 2019 Publication Optical Express Abbreviated Journal
Volume 27 Issue 14 Pages (down) 19075-19101
Keywords Instrumentation
Abstract Consumer cameras, particularly onboard smartphones and UAVs, are now commonly used as scientific instruments. However, their data processing pipelines are not optimized for quantitative radiometry and their calibration is more complex than that of scientific cameras. The lack of a standardized calibration methodology limits the interoperability between devices and, in the ever-changing market, ultimately the lifespan of projects using them. We present a standardized methodology and database (SPECTACLE) for spectral and radiometric calibrations of consumer cameras, including linearity, bias variations, read-out noise, dark current, ISO speed and gain, flat-field, and RGB spectral response. This includes golden standard ground-truth methods and do-it-yourself methods suitable for non-experts. Applying this methodology to seven popular cameras, we found high linearity in RAW but not JPEG data, inter-pixel gain variations >400% correlated with large-scale bias and read-out noise patterns, non-trivial ISO speed normalization functions, flat-field correction factors varying by up to 2.79 over the field of view, and both similarities and differences in spectral response. Moreover, these results differed wildly between camera models, highlighting the importance of standardization and a centralized database.
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Notes Approved no
Call Number IDA @ intern @ Serial 2652
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Author Zhang, Z.; Wang, H.-J.; Wang, D.-R.; Qu, W.-M.; Huang, Z.-L.
Title Red light at intensities above 10 lx alters sleep-wake behavior in mice Type Journal Article
Year 2017 Publication Light, Science & Applications Abbreviated Journal Light Sci Appl
Volume 6 Issue 5 Pages (down) e16231
Keywords Animals
Abstract Sleep is regulated by two mechanisms: the homeostatic process and the circadian clock. Light affects sleep and alertness by entraining the circadian clock, and acutely inducing sleep/alertness, in a manner mediated by intrinsically photosensitive retinal ganglion cells. Because intrinsically photosensitive retinal ganglion cells are believed to be minimally sensitive to red light, which is widely used for illumination to reduce the photic disturbance to nocturnal animals during the dark phase. However, the appropriate intensity of the red light is unknown. In the present study, we recorded electroencephalograms and electromyograms of freely moving mice to investigate the effects of red light emitted by light-emitting diodes at different intensities and for different durations on the sleep-wake behavior of mice. White light was used as a control. Unexpectedly, red light exerted potent sleep-inducing effects and changed the sleep architecture in terms of the duration and number of sleep episodes, the stage transition, and the EEG power density when the intensity was >20 lx. Subsequently, we lowered the light intensity and demonstrated that red light at or below 10 lx did not affect sleep-wake behavior. White light markedly induced sleep and disrupted sleep architecture even at an intensity as low as 10 lx. Our findings highlight the importance of limiting the intensity of red light (10 lx) to avoid optical influence in nocturnal behavioral experiments, particularly in the field of sleep and circadian research.
Address Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Department of Pharmacology, School of Basic Medical Sciences, State Key Laboratory of Medical Neurobiology and Shanghai Key Laboratory of Clinical Geriatric Medicine, Shanghai Medical College, Fudan University, Shanghai 200032, China
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Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2047-7538 ISBN Medium
Area Expedition Conference
Notes PMID:30167247; PMCID:PMC6062196 Approved no
Call Number GFZ @ kyba @ Serial 2463
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