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Author Wood, J.M.; Isoardi, G.; Black, A.; Cowling, I. url  doi
openurl 
  Title Night-time driving visibility associated with LED streetlight dimming Type Journal Article
  Year 2018 Publication Accident; Analysis and Prevention Abbreviated Journal Accid Anal Prev  
  Volume 121 Issue Pages 295-300  
  Keywords Public Safety  
  Abstract New LED streetlighting designs and dimming are being introduced worldwide, however, while their cost savings are well established, their impact on driving performance has received little attention. This study investigated the effect of streetlight dimming on night-time driving performance. Participants included 14 licensed drivers (mean age 34.2 +/- 4.9 years, range 27-40 years) who drove an instrumented vehicle around a closed circuit at night. Six LED streetlights were positioned along a 250 m, straight section and their light output varied between laps (dimming levels of 25%, 50%, 75% and 100% of maximum output; L25, L50, L75 and L100 respectively; at 100% average road surface luminance of 1.14 cd/m(2)). Driving tasks involved recognition distances and reaction times to a low contrast, moving target and a pedestrian walking at the roadside. Participants drove at an average driving speed of 55 km/hr in the streetlight zone. Streetlight dimming significantly delayed driver reaction times to the moving target (F3,13.06 = 6.404; p = 0.007); with an average 0.4 s delay in reaction times under L25 compared to L100, (estimated reduction in recognition distances of 6 m). Pedestrian recognition distances were significantly shorter under dimmed streetlight levels (F3,12.75 = 8.27; p = 0.003); average pedestrian recognition distances were 15 m shorter under L25 compared to L100, and 11 m shorter under L50 compared to L100. These data suggest that streetlight dimming impacts on driver visibility but it is unclear how these differences impact on safety; future studies are required to inform decisions on safe dimming levels for road networks.  
  Address School of Chemistry, Physics and Mechanical Engineering, Faculty of Science and Engineering Faculty, Queensland University of Technology, Brisbane, Queensland, Australia  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0001-4575 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30317014 Approved no  
  Call Number GFZ @ kyba @ Serial 2160  
Permanent link to this record
 

 
Author Bará, S. url  doi
openurl 
  Title Characterizing the zenithal night sky brightness in large territories: how many samples per square kilometre are needed? Type Journal Article
  Year 2017 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal  
  Volume 473 Issue 3 Pages 4164-4173  
  Keywords Instrumentation; atmospheric effects; light pollution; numerical methods; photometry  
  Abstract A recurring question arises when trying to characterize, by means of measurements or theoretical calculations, the zenithal night sky brightness throughout a large territory: how many samples per square kilometre are needed? The optimum sampling distance should allow reconstructing, with sufficient accuracy, the continuous zenithal brightness map across the whole region, whilst at the same time avoiding unnecessary and redundant oversampling. This paper attempts to provide some tentative answers to this issue, using two complementary tools: the luminance structure function and the Nyquist–Shannon spatial sampling theorem. The analysis of several regions of the world, based on the data from the New world atlas of artificial night sky brightness, suggests that, as a rule of thumb, about one measurement per square kilometre could be sufficient for determining the zenithal night sky brightness of artificial origin at any point in a region to within ±0.1 magV arcsec–2 (in the root-mean-square sense) of its true value in the Johnson–Cousins V band. The exact reconstruction of the zenithal night sky brightness maps from samples taken at the Nyquist rate seems to be considerably more demanding.  
  Address 1Departamento de Física Aplicada, Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Galicia, Spain; salva.bara(at)usc.es  
  Corporate Author Thesis  
  Publisher Oxford Academic Place of Publication Editor  
  Language (down) English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 2164  
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Author Sloane, P.D.; Williams, C.S.; Mitchell, C.M.; Preisser, J.S.; Wood, W.; Barrick, A.L.; Hickman, S.E.; Gill, K.S.; Connell, B.R.; Edinger, J.; Zimmerman, S. url  doi
openurl 
  Title High-intensity environmental light in dementia: effect on sleep and activity Type Journal Article
  Year 2007 Publication Journal of the American Geriatrics Society Abbreviated Journal J Am Geriatr Soc  
  Volume 55 Issue 10 Pages 1524-1533  
  Keywords Human Health  
  Abstract OBJECTIVES: To determine whether high-intensity ambient light in public areas of long-term care facilities will improve sleeping patterns and circadian rhythms of persons with dementia. DESIGN: A cluster-unit crossover intervention trial involving four conditions: morning bright light, evening bright light, all-day bright light, and minimum standard light. SETTING: The common areas of two geriatric units in a psychiatric hospital and a dementia-specific residential care facility. PARTICIPANTS: Sixty-six older adults with dementia. INTERVENTION: Ambient bright light of approximately 2,500 lux, delivered through a low-glare lighting system installed in the dining and activity areas. Participant exposure averaged 2.5 to 3.0 hours for the morning and evening interventions and 8.4 hours for the all-day intervention. MEASUREMENTS: Nighttime sleep using wrist actigraphy and daytime activity using nonobtrusive daytime observations. RESULTS: Night-time sleep increased significantly in participants exposed to morning and all-day light, with the increase most prominent in participants with severe or very severe dementia (mean increase 16 minutes (P=.008) for morning, and 14 minutes (P=.01) for all-day). Morning light produced a mean phase advance of 29 minutes (P=.02) and evening light a mean phase delay of 15 minutes (P=.06). Effects on daytime sleepiness were inconsistent, and the number of sleep bouts, mesor, amplitude, intradaily variability, and interdaily stability were not significantly different, indicating that the overall strength of day and night activity rhythms did not change significantly under any treatment condition. CONCLUSION: Bright light appears to have a modest but measurable effect on sleep in this population, and ambient light may be preferable to stationary devices such as light boxes.  
  Address Department of Family Medicine, School of Medicine; Cecil G.Sheps Center for Health Services Research, University of North Carolina, Chapel Hill, NC, USA. psloane@med.unc.edu  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0002-8614 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17714459 Approved no  
  Call Number GFZ @ kyba @ Serial 2168  
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Author Sanotra, G.S.; Lund, J.D.; Vestergaard, K.S. url  doi
openurl 
  Title Influence of light-dark schedules and stocking density on behaviour, risk of leg problems and occurrence of chronic fear in broilers Type Journal Article
  Year 2002 Publication British Poultry Science Abbreviated Journal Br Poult Sci  
  Volume 43 Issue 3 Pages 344-354  
  Keywords Animals  
  Abstract 1. The aims of this study were to determine (1) the effect of light-dark schedules on the walking ability, the risk of tibial dyschondroplasia (TD) as well as the duration of tonic immobility (TI) reactions in commercial broiler flocks and (2) the effect of a daily dark period and reduced density on the behaviour of broiler chickens. 2. Experiment 1. Group 1 had a 2 to 8 h daily dark period from 2 to 26 d of age (light-dark programme A) at a stocking density of 28.4 chicks/m2. Group 2 had 8 h of darkness daily from 2 to 38 d of age (light-dark programme B) at 24 chicks/m2. The control group had 24 h continuous light at 28.4 chicks/m2. 3. Experiment 2. Behaviour was studied with and without a daily 8 h dark period and at high (30 chicks/m2) and low (18 chicks/m2) stocking densities. 4. Programme B reduced the prevalence of impaired walking ability, corresponding to gait score > 2, when compared with controls. The effect on walking ability corresponding to gait score > 0 approached significance. 5. Both light-dark programmes reduced the occurrence of TD. Programme B (combined with reduced stocking density), however, had the greater effect. 6. Both light-dark programmes reduced the duration of TI, compared with controls (mean = 426 s) Programme B resulted in a larger reduction (alpha = -156.9 s) than programme A (alpha = -117.0). 7. The proportions of chicks drinking, eating, pecking, scratching, standing and performing vertical wing-shakes increased--both when the 8 h dark period and the reduced stocking density were applied separately and in combination (experiment 2). 8. For all behaviours, except standing, the effect of the dark period was largest in broilers kept at the high stocking density (d 40).  
  Address Department of Animal Science and Animal Health, Division of Ethology and Health, Royal Veterinary and Agricultural University, Groennegaardsvej 8, DK-1870 Frederiksberg C, Copenhagen, Denmark. sgs@kvl.dk  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0007-1668 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12195793 Approved no  
  Call Number GFZ @ kyba @ Serial 2169  
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Author Manríquez, P.H.; Jara, M.E.; Diaz, M.I.; Quijón, P.A.; Widdicombe, S.; Pulgar, J.; Manríquez, K.; Quintanilla-Ahumada, D.; Duarte, C. url  doi
openurl 
  Title Artificial light pollution influences behavioral and physiological traits in a keystone predator species, Concholepas concholepas Type Journal Article
  Year 2019 Publication Science of The Total Environment Abbreviated Journal Science of The Total Environment  
  Volume 661 Issue Pages 543-552  
  Keywords Animals; Concholepas concholepas; sea snails; mollusks; Muricidae  
  Abstract Artificial Light At Night (ALAN) is an increasing global problem that, despite being widely recognized in terrestrial systems, has been studied much less in marine habitats. In this study we investigated the effect of ALAN on behavioral and physiological traits of Concholepas concholepas, an important keystone species of the south-eastern Pacific coast. We used juveniles collected in intertidal habitats that had not previously been exposed to ALAN. In the laboratory we exposed them to two treatments: darkness and white LED (Lighting Emitting Diodes) to test for the impacts of ALAN on prey-searching behavior, self-righting time and metabolism. In the field, the distribution of juveniles was observed during daylight-hours to determine whether C. concholepas preferred shaded or illuminated microhabitats. Moreover, we compared the abundance of juveniles collected during day- and night-time hours. The laboratory experiments demonstrated that juveniles of C. concholepas seek out and choose their prey more efficiently in darkened areas. White LED illuminated conditions increased righting times and metabolism. Field surveys indicated that, during daylight hours, juveniles were more abundant in shaded micro-habitats than in illuminated ones. However, during darkness hours, individuals were not seen to aggregate in any particular microhabitats. We conclude that the exposure to ALAN might disrupt important behavioral and physiological traits of small juveniles in this species which, as a mechanism to avoid visual predators, are mainly active at night. It follows that ALAN in coastal areas might modify the entire community structure of intertidal habitats by altering the behavior of this keystone species.  
  Address Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Coquimbo, Chile; atriciohmanriquez(at)gmail.com  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language (down) English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0048-9697 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2173  
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