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Author Kocifaj, M.; Solano Lamphar, H.A. url  doi
openurl 
  Title Angular Emission Function of a City and Skyglow Modeling: A Critical Perspective Type Journal Article
  Year 2016 Publication Publications of the Astronomical Society of the Pacific Abbreviated Journal Pasp  
  Volume 128 Issue 970 Pages 124001  
  Keywords Skyglow  
  Abstract (down) The radiative transfer equation (RTE) is a common approach to solving the transfer of electromagnetic energy in heterogeneous disperse media, such as atmospheric environment. One-dimensional RTE is a linear boundary value problem that is well suited to plane-parallel atmosphere with no diffuse intensity entering the top of the atmosphere. In nighttime regime, the ground-based light sources illuminate the atmosphere at its bottom interface. However, the light-pollution models conventionally use radiant intensity function rather than radiance. This might potentially result in a number of misconceptions. We focused on similarities and fundamental differences between both functions and clarified distinct consequences for the modeling of skyglow from finite-sized and semi-infinite light-emitting flat surfaces. Minimum requirements to be fulfilled by a City Emission Function (CEF) are formulated to ensure a successful solution of standard and inverse problems. It has been shown that the horizon radiance of a flat surface emitting in accordance with Garstang's function (GEF) would exceed any limit, meaning that the GEF is not an appropriate tool to model skyglow from distant sources. We developed two alternative CEFs to remedy this problem through correction of direct upward emissions; the most important strengths of the modified CEFs are detailed in this paper. Numerical experiments on sky luminance under well-posed and ill-posed boundary conditions were made for two extreme uplight fractions (F) and for three discrete distances from the city edge. The errors induced by replacing radiance with radiant intensity function in the RTE are generally low (15%–30%) if F is as large as 0.15, but alteration of the luminance may range over 1–3 orders of magnitude if F approaches zero. In the latter case, the error margin can increase by a factor of 10–100 or even 1000, even if the angular structure of luminance patterns suffers only weak changes. This is why such a shift in luminance magnitudes can be mistakenly interpreted as the effect of inaccurate estimate of lumens per head of the population rather than the effect of cosine distortion due to ill-posed inputs to the RTE. For that reason, a thorough revision (and/or remediation) of theoretical and computational models is suggested.  
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  ISSN 0004-6280 ISBN Medium  
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  Notes Approved no  
  Call Number LoNNe @ kyba @ Serial 1564  
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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 (down) 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.
 
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  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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Author Coleman, G.; Gigg, J.; Canal, M.M. url  doi
openurl 
  Title Postnatal light alters hypothalamic-pituitary-adrenal (HPA) axis function and induces a depressive-like phenotype in adult mice Type Journal Article
  Year 2016 Publication The European Journal of Neuroscience Abbreviated Journal Eur J Neurosci  
  Volume 44 Issue 10 Pages 2807-2817  
  Keywords Animals  
  Abstract (down) The postnatal light environment that a mouse experiences during the critical first 3 postnatal weeks has long-term effects on both its circadian rhythm output and clock gene expression. Furthermore, data from our lab suggest that postnatal light may also impact the hypothalamic-pituitary-adrenal (HPA) axis, which is a key regulator of stress. To test the effect of postnatal light exposure on adult stress responses and circadian rhythmicity, we raised mice under either 24-h light-dark cycles (LD), constant light (LL) or constant dark (DD) during the first 3 postnatal weeks. After weaning we then exposed all animals to LD cycles (basal conditions), followed by LL (stressed conditions) environments. We examined brain neuropeptide and glucocorticoid receptor (GR) expression, plasma corticosterone concentration rhythm and body temperature rhythm, together with depression- and anxiety-related behaviour. Results showed that LL- and DD-raised mice exhibited decreased GR expression in the hippocampus, increased plasma corticosterone concentration at the onset of the dark phase and a depressive phenotype when exposed to LD cycles later in life. Furthermore, LL-raised mice showed increased corticotrophin-releasing hormone mRNA expression in the paraventricular nucleus of the hypothalamus. When exposed to LL as adults, LL-raised mice showed a significant circadian rhythm of plasma corticosterone concentration, together with a shorter period and stronger circadian rhythm of body temperature compared to DD-raised mice. Taken together, these data suggest that altered postnatal light environments have long-term effects on the HPA axis and the circadian system, which can lead to altered stress responses and a depressive phenotype in adulthood. This article is protected by copyright. All rights reserved.  
  Address Faculty of Life Sciences, University of Manchester, AV Hill Building, Oxford Road, M13 9PT, Manchester, UK. maria.canal@manchester.ac.uk  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0953-816X ISBN Medium  
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  Notes PMID:27591429 Approved no  
  Call Number LoNNe @ kyba @ Serial 1523  
Permanent link to this record
 

 
Author Hölker, Andreas; Doulos, Lambros; Schroer, Sibylle; Topalis, Frangiskos url  openurl
  Title Sustainable outdoor lighting for reducing energy and light waste Type Conference Article
  Year 2016 Publication 9th International Conference Improving Energy Efficiency in Commercial Buildings and Smart Communities Abbreviated Journal  
  Volume Issue Pages 202-213  
  Keywords lighting design; lighting technology; light pollution  
  Abstract (down) The lack of lighting planning for internal and external illumination of buildings contributes to wasting energy and to the issue of light pollution. This will be demonstrated with research from the ground and by analysis of images, taken with detectors on satellites, the International Space Station or planes. Besides large area floodlighting from airports or sports facilities, facade illumination is the most important contributor. The effects of malpractice versus sustainable lighting planning solutions will be demonstrated with some examples in cities like Bonn, Strasbourg, Athens and Thessaloniki. Further examples in the countryside will demonstrate lighting practice in the German star park Biosphere Reserve Rhön. Facade lighting planning, considering optimal alignment, the intensity and the colour quality of the illumination, will contribute to reducing light pollution and thus waste of energy and will increase human comfort at the same time.

Experience shows that unilateral promoting energy efficiency will finally result in more extended use of energy, which is known as rebound effect. In addition the small size and long lifetime of the modern solid state lighting will result in an increased use even in remote places thereby emitting more artificial light into the natural night. This does not only affect the energy use, but also the biological rhythms of animals and human beings.

More interdisciplinary criteria for a sustainable lighting with reduced light pollution will be discussed based on the observations including data provided by the EU-network “Loss of the Night”-Network (EU-COST Action ES1204 LoNNe).
 
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  Publisher JRC Confernce and workshop reports Place of Publication Editor  
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  Notes Approved no  
  Call Number LoNNe @ schroer @ Serial 1573  
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Author Walch, O.J.; Cochran, A.; Forger, D.B. url  doi
openurl 
  Title A global quantification of “normal” sleep schedules using smartphone data Type Journal Article
  Year 2016 Publication Science Advances Abbreviated Journal Science Advances  
  Volume 2 Issue 5 Pages e1501705-e1501705  
  Keywords Human Health; Sleep; *Circadian Rhythm; smartphone; society  
  Abstract (down) The influence of the circadian clock on sleep scheduling has been studied extensively in the laboratory; however, the effects of society on sleep remain largely unquantified. We show how a smartphone app that we have developed, ENTRAIN, accurately collects data on sleep habits around the world. Through mathematical modeling and statistics, we find that social pressures weaken and/or conceal biological drives in the evening, leading individuals to delay their bedtime and shorten their sleep. A country’s average bedtime, but not average wake time, predicts sleep duration. We further show that mathematical models based on controlled laboratory experiments predict qualitative trends in sunrise, sunset, and light level; however, these effects are attenuated in the real world around bedtime. Additionally, we find that women schedule more sleep than men and that users reporting that they are typically exposed to outdoor light go to sleep earlier and sleep more than those reporting indoor light. Finally, we find that age is the primary determinant of sleep timing, and that age plays an important role in the variability of population-level sleep habits. This work better defines and personalizes “normal” sleep, produces hypotheses for future testing in the laboratory, and suggests important ways to counteract the global sleep crisis.  
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  ISSN 2375-2548 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number LoNNe @ kyba @ Serial 1440  
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