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Author Nickla, D.L.; Totonelly, K. url  doi
openurl 
  Title Brief light exposure at night disrupts the circadian rhythms in eye growth and choroidal thickness in chicks Type Journal Article
  Year 2016 Publication Experimental eye Research Abbreviated Journal Exp Eye Res  
  Volume 146 Issue Pages 189-195  
  Keywords Animals  
  Abstract Changes in ocular growth that lead to myopia or hyperopia are associated with alterations in the circadian rhythms in eye growth, choroidal thickness and intraocular pressure in animal models of emmetropization. Recent studies have shown that light at night has deleterious effects on human health, acting via “circadian disruptions” of various diurnal rhythms, including changes in phase or amplitude. The purpose of this study was to determine the effects of brief, 2-hour episodes of light in the middle of the night on the rhythms in axial length and choroidal thickness, and whether these alter eye growth and refractive error in the chick model of myopia. Starting at 2 weeks of age, birds received 2 hours of light between 12:00 am and 2:00 am for 7 days (n=12; total hours of light: 14 hrs). Age-matched controls had a continuous dark night (n=14; 14L/10D). Ocular dimensions were measured using high-frequency A-scan ultrasonography on the first day of the experiment, and again on day 7, at 6-hour intervals, starting at noon (12pm, 6pm, 12am, 6am, 12pm). Measurements during the night were done under a photographic safe-light. These data were used to determine rhythm parameters of phase and amplitude. 2 groups of birds, both experimental (light at night) and control, were measured with ultrasound at various intervals over the course of 4 weeks to determine growth rates. Refractive errors were measured in 6 experimental and 6 control birds at the end of 2 weeks. Eyes of birds in a normal L/D cycle showed sinusoidal 24-hour period diurnal rhythms in axial length and choroid thickness. Light in the middle of the night caused changes in both the rhythms in axial length and choroidal thickness, such that neither could be fit to a sine function having a period of 24 hours. Light caused an acute, transient stimulation in ocular growth rate in the subsequent 6-hour period (12 am to 6 am), that may be responsible for the increased growth rate seen 4 weeks later, and the more myopic refractive error. It also abolished the increase in choroidal thickness that normally occurs between 6 pm and 12 am. We conclude that light at night alters the rhythms in axial length and choroidal thickness in an animal model of eye growth, and that these circadian disruptions might lead to the development of ametropias. These results have implications for the use of light during the night in children.  
  Address The New England College of Optometry, Boston, MA, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor (up)  
  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:26970497 Approved no  
  Call Number LoNNe @ kyba @ Serial 1371  
Permanent link to this record
 

 
Author Qiu, S.; Shao, X.; Cao, C.; Uprety, S. url  doi
openurl 
  Title Feasibility demonstration for calibrating Suomi-National Polar-Orbiting Partnership Visible Infrared Imaging Radiometer Suite day/night band using Dome C and Greenland under moon light Type Journal Article
  Year 2016 Publication Journal of Applied Remote Sensing Abbreviated Journal J. Appl. Remote Sens  
  Volume 10 Issue 1 Pages 016024  
  Keywords Remote Sensing; Instrumentation  
  Abstract The day/night band (DNB) of the Visible Infrared Imaging Radiometer Suite (VIIRS) onboard Suomi National Polar-orbiting Partnership (Suomi-NPP) represents a major advancement in night time imaging capabilities. DNB covers almost seven orders of magnitude in its dynamic range from full sunlight to half-moon. To achieve this large dynamic range, it uses four charge-coupled device arrays in three gain stages. The low gain stage (LGS) gain is calibrated using the solar diffuser. In operations, the medium and high gain stage values are determined by multiplying the gain ratios between the medium gain stage, and LGS, and high gain stage (HGS) and LGS, respectively. This paper focuses on independently verifying the radiometric accuracy and stability of DNB HGS using DNB observations of ground vicarious calibration sites under lunar illumination at night. Dome C in Antarctica in the southern hemisphere and Greenland in the northern hemisphere are chosen as the vicarious calibration sites. Nadir observations of these high latitude regions by VIIRS are selected during perpetual night season, i.e., from April to August for Dome C and from November to January for Greenland over the years 2012 to 2013. Additional selection criteria, such as lunar phase being more than half-moon and no influence of straylight effects, are also applied in data selection. The lunar spectral irradiance model, as a function of Sun–Earth–Moon distances and lunar phase, is used to determine the top-of-atmosphere reflectance at the vicarious site. The vicariously derived long-term reflectance from DNB observations agrees with the reflectance derived from Hyperion observations. The vicarious trending of DNB radiometric performance using DOME-C and Greenland under moon light shows that the DNB HGS radiometric variability (relative accuracy to lunar irradiance model and Hyperion observation) is within 8%. Residual variability is also discussed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor (up)  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1931-3195 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number LoNNe @ kyba @ Serial 1372  
Permanent link to this record
 

 
Author Li, C.; Hsu, N.C.; Sayer, A.M.; Krotkov, N.A.; Fu, J.S.; Lamsal, L.N.; Lee, J.; Tsay, S.-C. url  doi
openurl 
  Title Satellite observation of pollutant emissions from gas flaring activities near the Arctic Type Journal Article
  Year 2016 Publication Atmospheric Environment Abbreviated Journal Atmospheric Environment  
  Volume 133 Issue Pages 1-11  
  Keywords Remote Sensing  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor (up)  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1352-2310 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number LoNNe @ kyba @ Serial 1373  
Permanent link to this record
 

 
Author Stockl, A.L.; O'Carroll, D.C.; Warrant, E.J. url  doi
openurl 
  Title Neural Summation in the Hawkmoth Visual System Extends the Limits of Vision in Dim Light Type Journal Article
  Year 2016 Publication Current Biology : CB Abbreviated Journal Curr Biol  
  Volume 26 Issue 6 Pages 821-826  
  Keywords Vision; Animals  
  Abstract Most of the world's animals are active in dim light and depend on good vision for the tasks of daily life. Many have evolved visual adaptations that permit a performance superior to that of manmade imaging devices [1]. In insects, a major model visual system, nocturnal species show impressive visual abilities ranging from flight control [2, 3], to color discrimination [4, 5], to navigation using visual landmarks [6-8] or dim celestial compass cues [9, 10]. In addition to optical adaptations that improve their sensitivity in dim light [11], neural summation of light in space and time-which enhances the coarser and slower features of the scene at the expense of noisier finer and faster features-has been suggested to improve sensitivity in theoretical [12-14], anatomical [15-17], and behavioral [18-20] studies. How these summation strategies function neurally is, however, presently unknown. Here, we quantified spatial and temporal summation in the motion vision pathway of a nocturnal hawkmoth. We show that spatial and temporal summation combine supralinearly to substantially increase contrast sensitivity and visual information rate over four decades of light intensity, enabling hawkmoths to see at light levels 100 times dimmer than without summation. Our results reveal how visual motion is calculated neurally in dim light and how spatial and temporal summation improve sensitivity while simultaneously maximizing spatial and temporal resolution, thus extending models of insect motion vision derived predominantly from diurnal flies. Moreover, the summation strategies we have revealed may benefit manmade vision systems optimized for variable light levels [21].  
  Address Department of Biology, University of Lund, Solvegatan 35, 22362 Lund, Sweden  
  Corporate Author Thesis  
  Publisher Place of Publication Editor (up)  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0960-9822 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:26948877 Approved no  
  Call Number LoNNe @ kyba @ Serial 1374  
Permanent link to this record
 

 
Author Kolláth, Z.; Dömény, A.; Kolláth, K.; Nagy, B. url  doi
openurl 
  Title Qualifying lighting remodelling in a Hungarian city based on light pollution effects Type Journal Article
  Year 2016 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer  
  Volume 181 Issue Pages 46-51  
  Keywords Skyglow; Lighting  
  Abstract The public lighting system has been remodelled in several Hungarian cities. In some cases the majority of the old luminaries were fitted with high pressure sodium lamps and they were replaced with white LED lighting with a typical correlated colour temperature of about 4500 K. Therefore, these remodelling works provide a testbed for methods in measurements and modelling. We measured the luminance of the light domes of selected cities by DSLR photometry before and after the remodelling.

Thanks to the full cut off design of the new lighting fixtures we obtained a slight decrease even in the blue part of the sky dome spectra of a tested city. However, we have to note that this positive change is the result of the bad geometry (large ULR) of the previous lighting system. Based on Monte Carlo radiative transfer calculations we provide a comparison of different indicators that can be used to qualify the remodelling, and to predict the possible changes in light pollution.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor (up)  
  Language Summary Language 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 LoNNe @ kyba @; GFZ @ kyba @ Serial 1375  
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