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Author Bolshakov, C.V.; Bulyuk, V.N.; Sinelschikova, A.Y.; Vorotkov, M.V. url  openurl
  Title Influence of the vertical light beam on numbers and flight trajectories of night-migrating songbirds Type Journal Article
  Year 2013 Publication Avian Ecol. Behav. Abbreviated Journal  
  Volume 24 Issue Pages 35–49  
  Keywords Animals; nocturnal migration; light pollution; numbers; flight track; extrinsic factors  
  Abstract (up) In this paper we analyse the data obtained in the automatic regime by the Optical Electronic Device (OED, Vorotkov et al. 2009; Bolshakov et al. 2010) for autumn nocturnal passage of passerines on the Courish Spit on the Baltic Sea and estimate: (1) numbers aloft under differ- ent types of wind (following wind, opposing wind and calm conditions); (2) flight trajectories in the 5° cone of white light. We found that under natural nocturnal illumination conditions, the vertical cone of white light impacts the detectable numbers aloft and disturbs straight flight trajectories. The OED data obtained throughout the night suggest, after correction for ground speed and the mean flight altitude, the actual number of birds in the light cone peaks at calm conditions, is halved under following winds which are optimal for passage and is 21 times lower under unfavourable headwinds. It is assumed that high numbers in the light cone under calm conditions is an artefact of bird attraction by light and their concentration around the searchlights. The OED data obtained for midnight ±1 hour, flying migrants respond to the vertical light cone under all types of wind conditions by altering their straight flight trajec- tories. However, this response is most apparent in still air conditions. The proportion of birds that change their flight track reaches 43%. We assume that under such conditions some birds are not only attracted to the illuminated zone at low altitudes, but, besides slowing down their ground speed, change their trajectories to the degree of flying in circles. To determine combi- nations of factors and to test for their possible impact on the probability of response to light, we used a binary logistic regression. The presence of birds with straight vs. curved tracks was used as the dependent variable. Final logistic models obtained for midnight ±1 hour for calm conditions and headwinds, suggest that occurrence probability of songbirds with curvilinear flight tracks is higher for small birds, when no or just a small part of Moon disk is visible and under high air humidity. Under headwinds the probability of occurrence of birds flying curvi- linear tracks is also higher under overcast. For following winds, the probability of occurrence birds flying curvilinearly was higher when many small birds were aloft, when air humidity was high and when wind was not strictly following. Unlike other wind situations, this model did not include the size of visible part of the Moon disk as a significant factor. The increase of occurrence of curvilinear flight tracks through the light beam when winds were not exactly following was probably caused by the problems with compensating the lateral component of tailwinds under high velocities, especially by small birds.  
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  Call Number LoNNe @ christopher.kyba @ Serial 378  
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Author Sciezor, T. url  doi
openurl 
  Title A new astronomical method for determining the brightness of the night sky and its application to study long-term changes in the level of light pollution Type Journal Article
  Year 2013 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal Monthly Notices of the Royal Astronomical Society  
  Volume 435 Issue 1 Pages 303-310  
  Keywords light pollution methods; data analysis methods; observational site testing; comets; measurements; light pollution; skyglow  
  Abstract (up) In this paper, I present a new method that has been developed for determining the brightness of a cloudless night sky, on the basis of widely available amateur observations of comets. The tests show the correctness of the method, which makes it possible to determine the level of light pollution, defined as the brightness of the artificial sky glow, through the use of the archival observations of comets. The use of data bases of comet observations in Poland in the period 1994–2009 has led to a positive verification of the known model map of the brightness of the night sky. Also, it has been possible to find changes in the level of light pollution in this period, at the selected observation sites.  
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  ISSN 0035-8711 ISBN Medium  
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  Call Number IDA @ john @ Serial 266  
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Author Ge, A.; Du, Z.; Wang, W.; Qiu, P.; Wang, J.; Cai, J.; Song, X. url  doi
openurl 
  Title A composite optical system for a LED based headlamp low beam module Type Journal Article
  Year 2013 Publication Lighting Research and Technology Abbreviated Journal Lighting Research and Technology  
  Volume 45 Issue 6 Pages 752-757  
  Keywords Lighting  
  Abstract (up) In this paper, we propose a composite optical system for automotive headlamps. The system is composed of a paraboloid collimating reflector, an off-axis paraboloid reflector, a baffle and an imaging len. By using a LED as the light source, precise light distribution can be achieved. When making ray-tracing simulation for the composite optical system in TracePro, a clear cut-off line can be seen on the measuring screen, as well as a hotspot at the centre. The power consumption for the LED light sources in this system is less than 10 W, resulting in an energy efficiency of more than 58% and a maximum illumination of 26.76 lux at the centre hotspot.  
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  ISSN 1477-1535 ISBN Medium  
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  Call Number LoNNe @ kagoburian @ Serial 632  
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Author Shimoda, M.; Honda, K.-ichiro url  doi
openurl 
  Title Insect reactions to light and its applications to pest management Type Journal Article
  Year 2013 Publication Applied Entomology and Zoology Abbreviated Journal Appl Entomol Zool  
  Volume 48 Issue 4 Pages 413-421  
  Keywords ultraviolet; light; Integrated pest management; Artificial lighting; Photoreception; Phototaxis; Light-emitting diode; *Lighting  
  Abstract (up) Insects are able to see ultraviolet (UV) radiation. Nocturnal insects are often attracted to light sources that emit large amounts of UV radiation, and devices that exploit this behavior, such as light traps for forecasting pest outbreaks, and electric insect killers, have been developed. Some diurnal species are attracted to yellow; yellow pan traps are used for conducting surveys for pest outbreaks and yellow sticky plates are used for pest control. Lamps that give off yellow illumination have been used effectively to control the activity of nocturnal moths and thus reduce damage to fruit, vegetables, and flowers. Covering cultivation facilities with film that filters out near-UV radiation reduces the invasion of pests such as whiteflies and thrips into the facilities, thus reducing damage. Reflective material placed on cultivated land can control the approach of flying insects such as aphids. Future development and use of new light sources such as light-emitting diodes is anticipated for promoting integrated pest management.  
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  ISSN 0003-6862 ISBN Medium  
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  Call Number IDA @ john @ Serial 110  
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Author Narendra, A.; Reid, S.F.; Raderschall, C.A. url  doi
openurl 
  Title Navigational efficiency of nocturnal Myrmecia ants suffers at low light levels Type Journal Article
  Year 2013 Publication PloS one Abbreviated Journal PLoS One  
  Volume 8 Issue 3 Pages e58801  
  Keywords Adaptation, Biological/*physiology; Animals; Ants/*physiology; Australian Capital Territory; *Cues; Geographic Information Systems; Homing Behavior/*physiology; *Light; Locomotion/*physiology; Orientation/*physiology; insects  
  Abstract (up) Insects face the challenge of navigating to specific goals in both bright sun-lit and dim-lit environments. Both diurnal and nocturnal insects use quite similar navigation strategies. This is despite the signal-to-noise ratio of the navigational cues being poor at low light conditions. To better understand the evolution of nocturnal life, we investigated the navigational efficiency of a nocturnal ant, Myrmecia pyriformis, at different light levels. Workers of M. pyriformis leave the nest individually in a narrow light-window in the evening twilight to forage on nest-specific Eucalyptus trees. The majority of foragers return to the nest in the morning twilight, while few attempt to return to the nest throughout the night. We found that as light levels dropped, ants paused for longer, walked more slowly, the success in finding the nest reduced and their paths became less straight. We found that in both bright and dark conditions ants relied predominantly on visual landmark information for navigation and that landmark guidance became less reliable at low light conditions. It is perhaps due to the poor navigational efficiency at low light levels that the majority of foragers restrict navigational tasks to the twilight periods, where sufficient navigational information is still available.  
  Address ARC Centre of Excellence in Vision Science, Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, Australia. ajay.narendra@anu.edu.au  
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  ISSN 1932-6203 ISBN Medium  
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  Notes PMID:23484052; PMCID:PMC3590162 Approved no  
  Call Number IDA @ john @ Serial 117  
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