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Author Ren, Z.; Liu, Y.; Chen, B.; Xu, B. url  doi
openurl 
  Title Where Does Nighttime Light Come From? Insights from Source Detection and Error Attribution Type (up) Journal Article
  Year 2020 Publication Remote Sensing Abbreviated Journal Remote Sensing  
  Volume 12 Issue 12 Pages 1922  
  Keywords Remote Sensing  
  Abstract Nighttime light remote sensing has aroused great popularity because of its advantage in estimating socioeconomic indicators and quantifying human activities in response to the changing world. Despite many advances that have been made in method development and implementation of nighttime light remote sensing over the past decades, limited studies have dived into answering the question: Where does nighttime light come from? This hinders our capability of identifying specific sources of nighttime light in urbanized regions. Addressing this shortcoming, here we proposed a parcel-oriented temporal linear unmixing method (POTLUM) to identify specific nighttime light sources with the integration of land use data. Ratio of root mean square error was used as the measure to assess the unmixing accuracy, and parcel purity index and source sufficiency index were proposed to attribute unmixing errors. Using the Visible Infrared Imaging Radiometer Suite (VIIRS) nighttime light dataset from the Suomi National Polar-Orbiting Partnership (NPP) satellite and the newly released Essential Urban Land Use Categories in China (EULUC-China) product, we applied the proposed method and conducted experiments in two China cities with different sizes, Shanghai and Quzhou. Results of the POTLUM showed its relatively robust applicability of detecting specific nighttime light sources, achieving an rRMSE of 3.38% and 1.04% in Shanghai and Quzhou, respectively. The major unmixing errors resulted from using impure land parcels as endmembers (i.e., parcel purity index for Shanghai and Quzhou: 54.48%, 64.09%, respectively), but it also showed that predefined light sources are sufficient (i.e., source sufficiency index for Shanghai and Quzhou: 96.53%, 99.55%, respectively). The method presented in this study makes it possible to identify specific sources of nighttime light and is expected to enrich the estimation of structural socioeconomic indicators, as well as better support various applications in urban planning and management.  
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  Corporate Author Thesis  
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  Language Summary Language 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 GFZ @ kyba @ Serial 3032  
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Author Wuchterl, G.; Reithofer, M. openurl 
  Title Licht über Wien VII Type (up) Journal Article
  Year 2020 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords Skyglow; Energy  
  Abstract 231. Auf einen BlickDie Helligkeit des Wiener Nachthimmels hat sich stabilisiert. 2019 ist das zweite Jahr in Folge, in dem die Energie desLichts über Wien um weniger als 5 % zugenommen hat. Die Menge des künstlichen Lichts über Wien hat sich nach dem steilem Anstieg der Jahre 2009 bis 2014 auf hohem Niveau eingependelt..Es besteht ein enger Zusammenhang zwischen Licht- und Luftverschmutzung. Über 10 Jahre bestehende Korrelationen von Lichtimmissions- und Luftgüteindikatoren bestätigen dies. Auf dieser Erkenntnis beruht eine auf standardisierte Luft-güte-Bedingungen normierte Angabe der Globalstrahlung, mit der direkter auf die von der Stadt eingebrachten Lichtmenge geschlossen werden kann.Der Kunstlichthalo über Wien wurde mit einer neuen Methode vollständiger berechnet und enthält demnach deutlich mehr Energie als bisher angenommen. 500 Gigawattstunden und 100.000 Tonnen CO2-Äquivalent pro Jahr müssen als typischer Wert für eine Untergrenze angenommen werden.  
  Address  
  Corporate Author Thesis  
  Publisher Verein Kuffner-Sternwarte Place of Publication Vienna Editor  
  Language German Summary Language 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 GFZ @ kyba @ Serial 3033  
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Author Figueiro, M.G.; Bierman, A.; Plitnick, B.; Rea, M.S. url  doi
openurl 
  Title Preliminary evidence that both blue and red light can induce alertness at night Type (up) Journal Article
  Year 2009 Publication BMC Neuroscience Abbreviated Journal BMC Neurosci  
  Volume 10 Issue Pages 105  
  Keywords Adult; Alpha Rhythm; Analysis of Variance; Beta Rhythm; Circadian Rhythm/*physiology; Cornea/physiology; Dose-Response Relationship, Radiation; Electrocardiography; Female; Humans; *Light; Male; Melatonin/secretion; Middle Aged; *Photic Stimulation; Psychomotor Performance; Radioimmunoassay; Salivary Glands/secretion; Wakefulness/*physiology; physiology of vision; blue light; red light  
  Abstract BACKGROUND: A variety of studies have demonstrated that retinal light exposure can increase alertness at night. It is now well accepted that the circadian system is maximally sensitive to short-wavelength (blue) light and is quite insensitive to long-wavelength (red) light. Retinal exposures to blue light at night have been recently shown to impact alertness, implicating participation by the circadian system. The present experiment was conducted to look at the impact of both blue and red light at two different levels on nocturnal alertness. Visually effective but moderate levels of red light are ineffective for stimulating the circadian system. If it were shown that a moderate level of red light impacts alertness, it would have had to occur via a pathway other than through the circadian system. METHODS: Fourteen subjects participated in a within-subject two-night study, where each participant was exposed to four experimental lighting conditions. Each night each subject was presented a high (40 lx at the cornea) and a low (10 lx at the cornea) diffuse light exposure condition of the same spectrum (blue, lambda(max) = 470 nm, or red, lambda(max) = 630 nm). The presentation order of the light levels was counterbalanced across sessions for a given subject; light spectra were counterbalanced across subjects within sessions. Prior to each lighting condition, subjects remained in the dark (< 1 lx at the cornea) for 60 minutes. Electroencephalogram (EEG) measurements, electrocardiogram (ECG), psychomotor vigilance tests (PVT), self-reports of sleepiness, and saliva samples for melatonin assays were collected at the end of each dark and light periods. RESULTS: Exposures to red and to blue light resulted in increased beta and reduced alpha power relative to preceding dark conditions. Exposures to high, but not low, levels of red and of blue light significantly increased heart rate relative to the dark condition. Performance and sleepiness ratings were not strongly affected by the lighting conditions. Only the higher level of blue light resulted in a reduction in melatonin levels relative to the other lighting conditions. CONCLUSION: These results support previous findings that alertness may be mediated by the circadian system, but it does not seem to be the only light-sensitive pathway that can affect alertness at night.  
  Address Lighting Research Center, Rensselaer Polytechnic Institute, Troy, NY, USA. figuem@rpi.edu  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1471-2202 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:19712442; PMCID:PMC2744917 Approved no  
  Call Number IDA @ john @ Serial 285  
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Author Reddy, A.B.; O'Neill, J.S. url  doi
openurl 
  Title Healthy clocks, healthy body, healthy mind Type (up) Journal Article
  Year 2010 Publication Trends in Cell Biology Abbreviated Journal Trends Cell Biol  
  Volume 20 Issue 1 Pages 36-44  
  Keywords Aging; Animals; Cell Cycle; *Circadian Rhythm; Humans; Neoplasms/genetics/metabolism; Signal Transduction  
  Abstract Circadian rhythms permeate mammalian biology. They are manifested in the temporal organisation of behavioural, physiological, cellular and neuronal processes. Whereas it has been shown recently that these approximately 24-hour cycles are intrinsic to the cell and persist in vitro, internal synchrony in mammals is largely governed by the hypothalamic suprachiasmatic nuclei that facilitate anticipation of, and adaptation to, the solar cycle. Our timekeeping mechanism is deeply embedded in cell function and is modelled as a network of transcriptional and/or post-translational feedback loops. Concurrent with this, we are beginning to understand how this ancient timekeeper interacts with myriad cell systems, including signal transduction cascades and the cell cycle, and thus impacts on disease. An exemplary area where this knowledge is rapidly expanding and contributing to novel therapies is cancer, where the Period genes have been identified as tumour suppressors. In more complex disorders, where aetiology remains controversial, interactions with the clockwork are only now starting to be appreciated.  
  Address Department of Clinical Neurosciences, University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Cambridge CB2 OQQ, UK. abr20@cam.ac.uk  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0962-8924 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:19926479; PMCID:PMC2808409 Approved no  
  Call Number IDA @ john @ Serial 133  
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Author Kantermann, T.; Roenneberg, T. url  doi
openurl 
  Title Is light-at-night a health risk factor or a health risk predictor? Type (up) Journal Article
  Year 2009 Publication Chronobiology International Abbreviated Journal Chronobiol Int  
  Volume 26 Issue 6 Pages 1069-1074  
  Keywords *Chronobiology Disorders; Circadian Rhythm; Environmental Exposure; Humans; *Light; Neoplasms; Risk Factors  
  Abstract In 2007, the IARC (WHO) has classified “shift-work that involves circadian disruption” as potentially carcinogenic. Ample evidence leaves no doubt that shift-work is detrimental for health, but the mechanisms behind this effect are not well understood. The hormone melatonin is often considered to be a causal link between night shift and tumor development. The underlying “light-at-night” (LAN) hypothesis is based on the following chain of arguments: melatonin is a hormone produced under the control of the circadian clock at night, and its synthesis can be suppressed by light; as an indolamine, it potentially acts as a scavenger of oxygen radicals, which in turn can damage DNA, which in turn can cause cancer. Although there is no experimental evidence that LAN is at the basis of increased cancer rates in shiftworkers, the scenario “light at night can cause cancer” influences research, medicine, the lighting industry and (via the media) also the general public, well beyond shiftwork. It is even suggested that baby-lights, TVs, computers, streetlights, moonlight, emergency lights, or any so-called “light pollution” by urban developments cause cancer via the mechanisms proposed by the LAN hypothesis. Our commentary addresses the growing concern surrounding light pollution. We revisit the arguments of the LAN theory and put them into perspective regarding circadian physiology, physical likelihood (e.g., what intensities reach the retina), and potential risks, specifically in non-shiftworkers.  
  Address Institute for Medical Psychology, University of Munich LMU, Munich, Germany  
  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 0742-0528 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:19731106 Approved no  
  Call Number IDA @ john @ Serial 134  
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