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Author Cao, C.; Bai, Y.
Title Quantitative Analysis of VIIRS DNB Nightlight Point Source for Light Power Estimation and Stability Monitoring Type Journal Article
Year 2014 Publication Remote Sensing Abbreviated Journal Remote Sensing
Volume 6 Issue 12 Pages 11915-11935
Keywords Remote Sensing; light pollution; skyglow; VIIRS; VIIRS DNB; Suomi NPP; radiometry; radiative transfer; modelling
Abstract The high sensitivity and advanced onboard calibration on the Visible Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB) enables accurate measurements of low light radiances which leads to enhanced quantitative applications at night. The finer spatial resolution of DNB also allows users to examine social economic activities at urban scales. Given the growing interest in the use of the DNB data, there is a pressing need for better understanding of the calibration stability and absolute accuracy of the DNB at low radiances. The low light calibration accuracy was previously estimated at a moderate 15% using extended sources while the long-term stability has yet to be characterized. There are also several science related questions to be answered, for example, how the Earth’s atmosphere and surface variability contribute to the stability of the DNB measured radiances; how to separate them from instrument calibration stability; whether or not SI (International System of Units) traceable active light sources can be designed and installed at selected sites to monitor the calibration stability, radiometric and geolocation accuracy, and point spread functions of the DNB; furthermore, whether or not such active light sources can be used for detecting environmental changes, such as aerosols. This paper explores the quantitative analysis of nightlight point sources, such as those from fishing vessels, bridges, and cities, using fundamental radiometry and radiative transfer, which would be useful for a number of applications including search and rescue in severe weather events, as well as calibration/validation of the DNB. Time series of the bridge light data are used to assess the stability of the light measurements and the calibration of VIIRS DNB. It was found that the light radiant power computed from the VIIRS DNB data matched relatively well with independent assessments based on the in situ light installations, although estimates have to be made due to limited ground truth data and lack of suitable radiative transfer models. Results from time series analysis are encouraging in potentially being able to detect anomalies in the DNB calibration. The study also suggests that accurate ground based active lights, when properly designed and installed, can be used to monitor the stability of the VIIRS DNB calibration at near the specified minimum radiances (3 nW/cm^2/sr), and potentially can be used to monitor the environmental changes as well.
Address (down) NOAA (National Oceanic and Atmospheric Administration)/NESDIS (National Environmental Satellite, Data, and Information Service)/STAR (Center for Satellite Applications and Research), NCWCP, E/RA2, 5830 University Research Ct., Suite 2838, College Park, MD 20740, USA; Changyong.Cao@noaa.gov
Corporate Author Thesis
Publisher MDPI Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2072-4292 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1154
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Author Constant, N.
Title Geospatial assessment of artificial lighting impacts on sea turtles in Tortuguero, Costa Rica Type Manuscript
Year 2015 Publication Abbreviated Journal
Volume Issue Pages
Keywords Animals; sea turtles; light pollution; GIS; Tortuguero; Costa Rica
Abstract Between June and August 2014, I conducted walking surveys to map the nesting beach

and light sources using a Trimble Juno SB GPS unit, and I developed a GIS database that formed the basis for subsequent analyses and data visualization. I built STC’s monitoring data from 2004 through 2014 into a polygon layer of the beach subdivided into mile sections defined by mile markers erected by STC. During the new moon in June and July 2014, I conducted brightness surveys in concert with STC’s light surveys and measured brightness in units of luminance at 50-meter intervals along the beach using a Unihedron Sky Quality Meter. Using spatial data of the beach and light sources, luminance data from brightness assessments, and monitoring data from STC, I determined a mean luminance value for each mile section, examined the relationship between luminance and nesting activity, and mapped light pollution on the beach.

I found that mean luminance and the total number of green turtle emergences per mile section were significantly negatively correlated. Mean luminance exceeded the minimum threshold for light pollution in 6 of the 43 mile sections, and there were significantly fewer emergences in mile sections experiencing light pollution. Mean luminance was highest in mile sections adjacent to Tortuguero Village, where sources of artificial light were concentrated. These findings were consistent with STC’s light survey data, and mean light count and the total number of green turtle emergences per mile section from 2004 to 2014 were also significantly negatively correlated. Cumulatively, these results suggest that artificial lighting from adjacent development impacts green turtle utilization of nesting habitat and changes the spatial distribution of green turtle nesting activity on Tortuguero Beach.

These results were consistent with the findings of previous studies conducted on sea turtle nesting beaches and support the need for a turtle-friendly lighting initiative in Tortuguero.
Address (down) Nicholas School of the Environment, Duke University, 450 Research Dr, Durham, NC 27708 USA
Corporate Author Thesis Master's thesis
Publisher Duke University Place of Publication Durham, NC 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 1247
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Author Nickla, D.L.
Title Ocular diurnal rhythms and eye growth regulation: where we are 50 years after Lauber Type Journal Article
Year 2013 Publication Experimental eye Research Abbreviated Journal Exp Eye Res
Volume 114 Issue Pages 25-34
Keywords Vision; Human Health; Review
Abstract Many ocular processes show diurnal oscillations that optimize retinal function under the different conditions of ambient illumination encountered over the course of the 24 h light/dark cycle. Abolishing the diurnal cues by the use of constant darkness or constant light results in excessive ocular elongation, corneal flattening, and attendant refractive errors. A prevailing hypothesis is that the absence of the Zeitgeber of light and dark alters ocular circadian rhythms in some manner, and results in an inability of the eye to regulate its growth in order to achieve emmetropia, the matching of the front optics to eye length. Another visual manipulation that results in the eye growth system going into a “default” mode of excessive growth is form deprivation, in which a translucent diffuser deprives the eye of visual transients (spatial or temporal) while not significantly reducing light levels; these eyes rapidly elongate and become myopic. It has been hypothesized that form deprivation might constitute a type of “constant condition” whereby the absence of visual transients drives the eye into a similar default mode as that in response to constant light or dark. Interest in the potential influence of light cycles and ambient lighting in human myopia development has been spurred by a recent study showing a positive association between the amount of time that children spent outdoors and a reduced prevalence of myopia. The growing eyes of chickens and monkeys show a diurnal rhythm in axial length: Eyes elongate more during the day than during the night. There is also a rhythm in choroidal thickness that is in approximate anti-phase to the rhythm in eye length. The phases are altered in eyes growing too fast, in response to form deprivation or negative lenses, or too slowly, in response to myopic defocus, suggesting an influence of phase on the emmetropization system. Other potential rhythmic influences include dopamine and melatonin, which form a reciprocal feedback loop, and signal “day” and “night” respectively. Retinal dopamine is reduced during the day in form deprived myopic eyes, and dopamine D2 agonists inhibit ocular growth in animal models. Rhythms in intraocular pressure as well, may influence eye growth, perhaps as a mechanical stimulus triggering changes in scleral extracellular matrix synthesis. Finally, evidence shows varying influences of environmental lighting parameters on the emmetropization system, such as high intensity light being protective against myopia in chickens. This review will cover the evidence for the possible influence of these various factors on ocular growth. The recognition that ocular rhythms may play a role in emmetropization is a first step toward understanding how they may be manipulated in treatment therapies to prevent myopia in humans.
Address (down) New England College of Optometry, Department of Biosciences, 424 Beacon Street, Boston, MA 02115, USA. nicklad@neco.edu
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 0014-4835 ISBN Medium
Area Expedition Conference
Notes PMID:23298452; PMCID:PMC3742730 Approved no
Call Number GFZ @ kyba @ Serial 1987
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Author Leise, T.L.; Goldberg, A.; Michael, J.; Montoya, G.; Solow, S.; Molyneux, P.; Vetrivelan, R.; Harrington, M.E.
Title Recurring circadian disruption alters circadian clock sensitivity to resetting Type Journal Article
Year 2018 Publication The European Journal of Neuroscience Abbreviated Journal Eur J Neurosci
Volume in press Issue Pages
Keywords Animals
Abstract A single phase advance of the light:dark (LD) cycle can temporarily disrupt synchrony of neural circadian rhythms within the suprachiasmatic nucleus (SCN) and between the SCN and peripheral tissues. Compounding this, modern life can involve repeated disruptive light conditions. To model chronic disruption to the circadian system, we exposed male mice to more than a month of a 20 h light cycle (LD10:10), which mice typically cannot entrain to. Control animals were housed under LD12:12. We measured locomotor activity and body temperature rhythms in vivo, and rhythms of PER2::LUC bioluminescence in SCN and peripheral tissues ex vivo. Unexpectedly, we discovered strong effects of the time of dissection on circadian phase of PER2::LUC bioluminescent rhythms, which varied across tissues. White adipose tissue was strongly reset by dissection, while thymus phase appeared independent of dissection timing. Prior light exposure impacted the SCN, resulting in strong resetting of SCN phase by dissection for mice housed under LD10:10, and weak phase shifts by time of dissection in SCN from control LD12:12 mice. These findings suggest that exposure to circadian disruption may desynchronize SCN neurons, increasing network sensitivity to perturbations. We propose that tissues with a weakened circadian network, such as the SCN under disruptive light conditions, or with little to no coupling, e.g., some peripheral tissues, will show increased resetting effects. In particular, exposure to light at inconsistent circadian times on a recurring weekly basis disrupts circadian rhythms and alters sensitivity of the SCN neural pacemaker to dissection time. This article is protected by copyright. All rights reserved.
Address (down) Neuroscience Program, Smith College, Northampton, MA, 01063, USA
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 0953-816X ISBN Medium
Area Expedition Conference
Notes PMID:30269396 Approved no
Call Number GFZ @ kyba @ Serial 2036
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Author Cho, E.; Oh, J.H.; Lee, E.; Do, Y.R.; Kim, E.Y.
Title Cycles of circadian illuminance are sufficient to entrain and maintain circadian locomotor rhythms in Drosophila Type Journal Article
Year 2016 Publication Scientific Reports Abbreviated Journal Sci Rep
Volume 6 Issue Pages 37784
Keywords Animals
Abstract Light at night disrupts the circadian clock and causes serious health problems in the modern world. Here, we show that newly developed four-package light-emitting diodes (LEDs) can provide harmless lighting at night. To quantify the effects of light on the circadian clock, we employed the concept of circadian illuminance (CIL). CIL represents the amount of light weighted toward the wavelengths to which the circadian clock is most sensitive, whereas visual illuminance (VIL) represents the total amount of visible light. Exposure to 12 h:12 h cycles of white LED light with high and low CIL values but a constant VIL value (conditions hereafter referred to as CH/CL) can entrain behavioral and molecular circadian rhythms in flies. Moreover, flies re-entrain to phase shift in the CH/CL cycle. Core-clock proteins are required for the rhythmic behaviors seen with this LED lighting scheme. Taken together, this study provides a guide for designing healthful white LED lights for use at night, and proposes the use of the CIL value for estimating the harmful effects of any light source on organismal health.
Address (down) Neuroscience Graduate Program, BK21 Plus Program, Department of Biomedical Sciences, Ajou University School of Medicine, 164 Worldcup-ro, Suwon, 16499, Republic of Korea
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 2045-2322 ISBN Medium
Area Expedition Conference
Notes PMID:27883065; PMCID:PMC5121609 Approved no
Call Number LoNNe @ kyba @ Serial 1565
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