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Author Korompeli, A.; Kavrochorianou, N.; Molcan, L.; Muurlink, O.; Boutzouka, E.; Myrianthefs, P.; Fildissis, G. url  doi
openurl 
  Title Light affects heart rate's 24-h rhythmicity in intensive care unit patients: an observational study Type Journal Article
  Year 2019 Publication Nursing in Critical Care Abbreviated Journal Nurs Crit Care  
  Volume 24 Issue 5 Pages (down) 320-325  
  Keywords Lighting; Human Health; Heart Rate; ICU; Circadian Rhythm  
  Abstract BACKGROUND: Intensive care unit (ICU) patients experience two affronts to normal 24-h rhythms: largely internal events such as medication and external factors such as light, noise and nursing interventions. AIMS AND OBJECTIVES: We investigated the impact of light variance within an ICU on 24-h rhythmicity of three key physiological parameters: heart rate (HR), mean arterial blood pressure (MAP) and body temperature (BT) in this patient population. DESIGN: Patients were assigned to beds either in the 'light' or 'dark' side within a single ICU. An actigraph continuously recorded light intensity for a 24-72-h period. METHODS: Measurements of HR, MAP and BT were recorded every 30 min. RESULTS: HR, MAP and BT did not follow 24-h rhythmicity in all patients. Higher light exposure in the Light Side of the ICU (122.3 versus 50.6 lx) was related to higher HR (89.4 versus 79.8 bpm), which may translate to clinically relevant outcomes in a larger sample. Duration of stay, the one clinical outcome measured in this study, showed no significant variation between the groups (p = 0.147). CONCLUSIONS: ICU patients are exposed to varying light intensities depending on bed positioning relative to natural sunlight, affecting the 24-h rhythm of HR. Larger, well-controlled studies also investigating the effect of relevant light intensity are indicated. RELEVANCE TO CLINICAL PRACTICE: Light is a variable that can be manipulated in the constrained environment of an ICU, thus offering an avenue for relatively unobtrusive interventions.  
  Address National and Kapodistrian University of Athens, University ICU, Ag. Anargyroi General Hospital, Athens, Greece  
  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 1362-1017 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:31087602 Approved no  
  Call Number GFZ @ kyba @ Serial 2502  
Permanent link to this record
 

 
Author Tabaka, P.; Rozga, P. url  doi
openurl 
  Title Influence of a Light Source Installed in a Luminaire of Opal Sphere Type on the Effect of Light Pollution Type Journal Article
  Year 2020 Publication Energies Abbreviated Journal Energies  
  Volume 13 Issue 2 Pages (down) 306  
  Keywords Lighting  
  Abstract The article presents the results of the studies concerning the influence of a light source installed in luminaire of opal sphere type on the light pollution effect of the night sky. It is known from literature reports that the effect of light pollution is influenced by the spectral distribution of light. Although the influence of the spectral distribution has been widely studied from different perspectives, there is still a need to study this phenomenon—for example, from the point of view of the spectral reflection properties of the ground, on which the lanterns are installed. Hence, the above-mentioned aspect was considered in the authors’ investigations. The luminaire considered has been equipped with 20 different light sources, including the latest generation of lamps (light-emitting diodes, LEDs) as well as the conventional ones. With respect to these light sources, the measurements of light distribution and spectral distribution of emitted radiation of the luminaire were performed. Having these measurement data, the simulations were carried out using the DIALux software, and the calculations were made using the specially prepared calculation tool. On the basis of the results obtained in this way this was stated that the type of light source installed in the luminaire has a significant effect on the sky glow. An important factor affecting light pollution is not only the value of the luminous flux emitted upward but also the spectral characteristics of the emitted radiation, the impact of which is most noticeable. The conclusions from the studies indicate the next steps in the analysis of the light pollution effect. These steps will be focused on extended analysis of LEDs as modern and developed light sources.  
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  ISSN 1996-1073 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2815  
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Author Evans, J.A.; Carter, S.N.; Freeman, D.A.; Gorman, M.R. url  doi
openurl 
  Title Dim nighttime illumination alters photoperiodic responses of hamsters through the intergeniculate leaflet and other photic pathways Type Journal Article
  Year 2012 Publication Neuroscience Abbreviated Journal Neuroscience  
  Volume 202 Issue Pages (down) 300-308  
  Keywords Animals; Biological Clocks/physiology; Circadian Rhythm/physiology; Cricetinae; Darkness; Data Interpretation, Statistical; Geniculate Bodies/*physiology; *Lighting; Male; Motor Activity/physiology; Phodopus; *Photoperiod; Visual Pathways/*physiology  
  Abstract In mammals, light entrains the central pacemaker within the suprachiasmatic nucleus (SCN) through both a direct neuronal projection from the retina and an indirect projection from the intergeniculate leaflet (IGL) of the thalamus. Although light comparable in intensity to moonlight is minimally effective at resetting the phase of the circadian clock, dimly lit and completely dark nights are nevertheless perceived differentially by the circadian system, even when nighttime illumination is below putative thresholds for phase resetting. Under a variety of experimental paradigms, dim nighttime illumination exerts effects that may be characterized as enhancing the plasticity of circadian entrainment. For example, relative to completely dark nights, dimly lit nights accelerate development of photoperiodic responses of Siberian hamsters transferred from summer to winter day lengths. Here we assess the neural pathways underlying this response by testing whether IGL lesions eliminate the effects of dim nighttime illumination under short day lengths. Consistent with previous work, dimly lit nights facilitated the expansion of activity duration under short day lengths. Ablation of the IGL, moreover, did not influence photoperiodic responses in animals held under completely dark nights. However, among animals that were provided dimly lit nights, IGL lesions prevented the short-day typical expansion of activity duration as well as the seasonally appropriate gonadal regression and reduction in body weight. Thus, the present data indicate that the IGL plays a central role in mediating the facilitative effects of dim nighttime illumination under short day lengths, but in the absence of the IGL, dim light at night influences photoperiodic responses through residual photic pathways.  
  Address Department of Psychology, University of California, San Diego, La Jolla, CA, USA. jevans@msm.edu  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0306-4522 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:22155265; PMCID:PMC3578228 Approved no  
  Call Number IDA @ john @ Serial 87  
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Author Kocifaj, M.; Solano Lamphar, H.A. url  doi
openurl 
  Title Skyglow effects in UV and visible spectra: radiative fluxes Type Journal Article
  Year 2013 Publication Journal of Environmental Management Abbreviated Journal J Environ Manage  
  Volume 127 Issue Pages (down) 300-307  
  Keywords Animals; Darkness; Environmental Exposure/*analysis; *Light; Models, Theoretical; *Ultraviolet Rays; Light pollution; Optical thickness; Public lighting system; Two stream approximation  
  Abstract Several studies have tried to understand the mechanisms and effects of radiative transfer under different night-sky conditions. However, most of these studies are limited to the various effects of visible spectra. Nevertheless, the invisible parts of the electromagnetic spectrum can pose a more profound threat to nature. One visible threat is from what is popularly termed skyglow. Such skyglow is caused by injudiciously situated or designed artificial night lighting systems which degrade desired sky viewing. Therefore, since lamp emissions are not limited to visible electromagnetic spectra, it is necessary to consider the complete spectrum of such lamps in order to understand the physical behaviour of diffuse radiation at terrain level. In this paper, the downward diffuse radiative flux is computed in a two-stream approximation and obtained ultraviolet spectral radiative fluxes are inter-related with luminous fluxes. Such a method then permits an estimate of ultraviolet radiation if the traditionally measured illuminance on a horizontal plane is available. The utility of such a comparison of two spectral bands is shown, using the different lamp types employed in street lighting. The data demonstrate that it is insufficient to specify lamp type and its visible flux production independently of each other. Also the UV emissions have to be treated by modellers and environmental scientists because some light sources can be fairly important pollutants in the near ultraviolet. Such light sources can affect both the living organisms and ambient environment.  
  Address ICA, Slovak Academy of Sciences, 9, Dubravska Road, 845 03 Bratislava, Slovak Republic. kocifaj@savba.sk  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0301-4797 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23792881 Approved no  
  Call Number IDA @ john @ Serial 265  
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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 112 Issue Pages (down) 296-305  
  Keywords Lighting  
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  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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