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Author Galatanu, C.D. url  doi
openurl 
  Title Study of Facades with Diffuse Asymmetrical Reflectance to Reduce Light Pollution Type Journal Article
  Year 2017 Publication Energy Procedia Abbreviated Journal Energy Procedia  
  Volume (down) 112 Issue Pages 296-305  
  Keywords Lighting  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1876-6102 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number LoNNe @ kyba @ Serial 1651  
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Author West, K.E.; Jablonski, M.R.; Warfield, B.; Cecil, K.S.; James, M.; Ayers, M.A.; Maida, J.; Bowen, C.; Sliney, D.H.; Rollag, M.D.; Hanifin, J.P.; Brainard, G.C. url  doi
openurl 
  Title Blue light from light-emitting diodes elicits a dose-dependent suppression of melatonin in humans Type Journal Article
  Year 2011 Publication Journal of Applied Physiology (Bethesda, Md. : 1985) Abbreviated Journal J Appl Physiol (1985)  
  Volume (down) 110 Issue 3 Pages 619-626  
  Keywords Circadian Rhythm/*physiology/*radiation effects; Color; Dose-Response Relationship, Radiation; Humans; Lighting/*methods; Melatonin/*blood; Metabolic Clearance Rate/radiation effects; Photic Stimulation/*methods; Radiation Dosage; Retina/*physiology/*radiation effects; Semiconductors; Young Adult; blue light  
  Abstract Light suppresses melatonin in humans, with the strongest response occurring in the short-wavelength portion of the spectrum between 446 and 477 nm that appears blue. Blue monochromatic light has also been shown to be more effective than longer-wavelength light for enhancing alertness. Disturbed circadian rhythms and sleep loss have been described as risk factors for astronauts and NASA ground control workers, as well as civilians. Such disturbances can result in impaired alertness and diminished performance. Prior to exposing subjects to short-wavelength light from light-emitting diodes (LEDs) (peak lambda = 469 nm; 1/2 peak bandwidth = 26 nm), the ocular safety exposure to the blue LED light was confirmed by an independent hazard analysis using the American Conference of Governmental Industrial Hygienists exposure limits. Subsequently, a fluence-response curve was developed for plasma melatonin suppression in healthy subjects (n = 8; mean age of 23.9 +/- 0.5 years) exposed to a range of irradiances of blue LED light. Subjects with freely reactive pupils were exposed to light between 2:00 and 3:30 AM. Blood samples were collected before and after light exposures and quantified for melatonin. The results demonstrate that increasing irradiances of narrowband blue-appearing light can elicit increasing plasma melatonin suppression in healthy subjects (P < 0.0001). The data were fit to a sigmoidal fluence-response curve (R(2) = 0.99; ED(50) = 14.19 muW/cm(2)). A comparison of mean melatonin suppression with 40 muW/cm(2) from 4,000 K broadband white fluorescent light, currently used in most general lighting fixtures, suggests that narrow bandwidth blue LED light may be stronger than 4,000 K white fluorescent light for suppressing melatonin.  
  Address Dept. of Neurology, Thomas Jefferson Univ., Philadelphia, Pennsylvania 19107, USA  
  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 0161-7567 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:21164152 Approved no  
  Call Number IDA @ john @ Serial 287  
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Author Cajochen, C.; Frey, S.; Anders, D.; Spati, J.; Bues, M.; Pross, A.; Mager, R.; Wirz-Justice, A.; Stefani, O. url  doi
openurl 
  Title Evening exposure to a light-emitting diodes (LED)-backlit computer screen affects circadian physiology and cognitive performance Type Journal Article
  Year 2011 Publication Journal of Applied Physiology (Bethesda, Md. : 1985) Abbreviated Journal J Appl Physiol (1985)  
  Volume (down) 110 Issue 5 Pages 1432-1438  
  Keywords Adult; Circadian Rhythm/*physiology/radiation effects; Cognition/*physiology/radiation effects; *Computer Terminals; Humans; Light; Lighting/*methods; Male; Photic Stimulation/*methods; Radiation Dosage; Semiconductors; *Task Performance and Analysis; Young Adult; blue light; sleep; circadian disruption  
  Abstract Many people spend an increasing amount of time in front of computer screens equipped with light-emitting diodes (LED) with a short wavelength (blue range). Thus we investigated the repercussions on melatonin (a marker of the circadian clock), alertness, and cognitive performance levels in 13 young male volunteers under controlled laboratory conditions in a balanced crossover design. A 5-h evening exposure to a white LED-backlit screen with more than twice as much 464 nm light emission {irradiance of 0,241 Watt/(steradian x m(2)) [W/(sr x m(2))], 2.1 x 10(13) photons/(cm(2) x s), in the wavelength range of 454 and 474 nm} than a white non-LED-backlit screen [irradiance of 0,099 W/(sr x m(2)), 0.7 x 10(13) photons/(cm(2) x s), in the wavelength range of 454 and 474 nm] elicited a significant suppression of the evening rise in endogenous melatonin and subjective as well as objective sleepiness, as indexed by a reduced incidence of slow eye movements and EEG low-frequency activity (1-7 Hz) in frontal brain regions. Concomitantly, sustained attention, as determined by the GO/NOGO task; working memory/attention, as assessed by “explicit timing”; and declarative memory performance in a word-learning paradigm were significantly enhanced in the LED-backlit screen compared with the non-LED condition. Screen quality and visual comfort were rated the same in both screen conditions, whereas the non-LED screen tended to be considered brighter. Our data indicate that the spectral profile of light emitted by computer screens impacts on circadian physiology, alertness, and cognitive performance levels. The challenge will be to design a computer screen with a spectral profile that can be individually programmed to add timed, essential light information to the circadian system in humans.  
  Address Centre for Chronobiology, Psychiatric Hospitals of the University of Basel, Basel, Switzerland. christian.cajochen@upkbs.ch  
  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 0161-7567 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:21415172 Approved no  
  Call Number IDA @ john @ Serial 293  
Permanent link to this record
 

 
Author Srinivasan, V.; Spence, D.W.; Pandi-Perumal, S.R.; Trakht, I.; Esquifino, A.I.; Cardinali, D.P.; Maestroni, G.J. url  doi
openurl 
  Title Melatonin, environmental light, and breast cancer Type Journal Article
  Year 2008 Publication Breast Cancer Research and Treatment Abbreviated Journal Breast Cancer Res Treat  
  Volume (down) 108 Issue 3 Pages 339-350  
  Keywords Human Health; Breast Neoplasms/*etiology/*physiopathology; Circadian Rhythm/physiology; Female; Humans; Light; Lighting/*adverse effects; Melatonin/*physiology; Occupational Exposure/adverse effects  
  Abstract Although many factors have been suggested as causes for breast cancer, the increased incidence of the disease seen in women working in night shifts led to the hypothesis that the suppression of melatonin by light or melatonin deficiency plays a major role in cancer development. Studies on the 7,12-dimethylbenz[a]anthracene and N-methyl-N-nitrosourea experimental models of human breast cancer indicate that melatonin is effective in reducing cancer development. In vitro studies in MCF-7 human breast cancer cell line have shown that melatonin exerts its anticarcinogenic actions through a variety of mechanisms, and that it is most effective in estrogen receptor (ER) alpha-positive breast cancer cells. Melatonin suppresses ER gene, modulates several estrogen dependent regulatory proteins and pro-oncogenes, inhibits cell proliferation, and impairs the metastatic capacity of MCF-7 human breast cancer cells. The anticarcinogenic action on MCF-7 cells has been demonstrated at the physiological concentrations of melatonin attained at night, suggesting thereby that melatonin acts like an endogenous antiestrogen. Melatonin also decreases the formation of estrogens from androgens via aromatase inhibition. Circulating melatonin levels are abnormally low in ER-positive breast cancer patients thereby supporting the melatonin hypothesis for breast cancer in shift working women. It has been postulated that enhanced endogenous melatonin secretion is responsible for the beneficial effects of meditation as a form of psychosocial intervention that helps breast cancer patients.  
  Address Department of Physiology, School of Medical Sciences, University Sains Malaysia, Kubang Kerian, Kelantan, Malaysia  
  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 0167-6806 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17541739 Approved no  
  Call Number LoNNe @ kagoburian @ Serial 815  
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Author Ebbensgaard, C.L. url  doi
openurl 
  Title Making sense of diodes and sodium: Vision, visuality and the everyday experience of infrastructural change Type Journal Article
  Year 2019 Publication Geoforum Abbreviated Journal Geoforum  
  Volume (down) 103 Issue Pages 95-104  
  Keywords Lighting; visual sensorium; United Kingdom  
  Abstract The recognition of vision as a powerful register for organising urban space locates lighting technologies at the heart of urban experience. Recently, scholars have established that lighting technologies shape not just what we see but how we see, drawing attention towards light as that ‘with which we see’. This article shifts attention from the role of lighting in shaping what and how people see, to how people make sense of changes to their visual sensorium—from what lighting infrastructures do to what is done with them. By following older residents living in the London Borough of Newham along routine travels on foot at night, I demonstrate how they make sense of the Council’s initiative to upgrade their 19,500 street-lamps with Light Emitting Diodes. I demonstrate how such infrastructural change exposes an uneven geographical distribution of and access to light and darkness with potentially detrimental consequences for the formation of public life after dark. Recognising how light infrastructures are reframed through everyday life, I demonstrate how LEDs do not necessarily produce their desired effects and how light clutter and light bleed might contribute to producing nocturnal atmospheres where people feel safe and confident. Broadening the understanding of how different technologies and light sources are important for the formation of inclusive nocturnal publics the article sets out a ‘politics of visibility’ that recognises the role of lighting in creating visibility for and of residents.  
  Address Queen Mary University of London, 329 Mile End Road, London E1 4NS, United Kingdom; c.l.ebbensgaard(at)qmul.ac.uk  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0016-7185 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2360  
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