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Author (up) Kocifaj, M. url  doi
openurl 
  Title Towards a Comprehensive City Emission Function (CCEF) Type Journal Article
  Year 2018 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal JQSRT  
  Volume 205 Issue Pages 253-266  
  Keywords Lighting; Skyglow  
  Abstract The comprehensive city emission function (CCEF) is developed for a heterogeneous light-emitting or blocking urban environments, embracing any combination of input parameters that characterize linear dimensions in the system (size and distances between buildings or luminaires), properties of light-emitting elements (such as luminous building façades and street lighting), ground reflectance and total uplight-fraction, all of these defined for an arbitrarily sized 2D area. The analytical formula obtained is not restricted to a single model class as it can capture any specific light-emission feature for wide range of cities. The CCEF method is numerically fast in contrast to what can be expected of other probabilistic approaches that rely on repeated random sampling. Hence the present solution has great potential in light-pollution modeling and can be included in larger numerical models. Our theoretical findings promise great progress in light-pollution modeling as this is the first time an analytical solution to city emission function (CEF) has been developed that depends on statistical mean size and height of city buildings, inter-building separation, prevailing heights of light fixtures, lighting density, and other factors such as e.g. luminaire light output and light distribution, including the amount of uplight, and representative city size. The model is validated for sensitivity and specificity pertinent to combinations of input parameters in order to test its behavior under various conditions, including those that can occur in complex urban environments. It is demonstrated that the solution model succeeds in reproducing a light emission peak at some elevated zenith angles and is consistent with reduced rather than enhanced emission in directions nearly parallel to the ground.  
  Address  
  Corporate Author Thesis  
  Publisher ScienceDirect Place of Publication Editor  
  Language English Summary Language English 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 LoNNe @ kyba @ Serial 1757  
Permanent link to this record
 

 
Author (up) Koen, E.L.; Minnaar, C.; Roever, C.L.; Boyles, J.G. url  doi
openurl 
  Title Emerging threat of the 21(st) century lightscape to global biodiversity Type Journal Article
  Year 2018 Publication Global Change Biology Abbreviated Journal Glob Chang Biol  
  Volume 24 Issue 6 Pages 2315-2324  
  Keywords Animals; Ecology; Remote Sensing  
  Abstract Over the last century the temporal and spatial distribution of light on Earth has been drastically altered by human activity. Despite mounting evidence of detrimental effects of light pollution on organisms and their trophic interactions, the extent to which light pollution threatens biodiversity on a global scale remains unclear. We assessed the spatial extent and magnitude of light encroachment by measuring change in the extent of light using satellite imagery from 1992 to 2012 relative to species richness for terrestrial and freshwater mammals, birds, reptiles, and amphibians. The encroachment of light into previously dark areas was consistently high, often doubling, in areas of high species richness for all four groups. This pattern persisted for nocturnal groups (e.g., bats, owls, and geckos) and species considered vulnerable to extinction. Areas with high species richness and large increases in light extent were clustered within newly industrialized regions where expansion of light is likely to continue unabated unless we act to conserve remaining darkness. Implementing change at a global scale requires global public, and therefore scientific, support. Here, we offer substantial evidence that light extent is increasing where biodiversity is high, representing an emerging threat to global biodiversity requiring immediate attention. This article is protected by copyright. All rights reserved.  
  Address Center for Ecology and Department of Zoology, Southern Illinois University, Carbondale, Illinois, 62901, 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 1354-1013 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:29575356 Approved no  
  Call Number GFZ @ kyba @ Serial 1833  
Permanent link to this record
 

 
Author (up) Kong, Y.; Stasiak, M.; Dixon, M.A.; Zheng, Y. url  doi
openurl 
  Title Blue light associated with low phytochrome activity can promote elongation growth as shade-avoidance response: A comparison with red light in four bedding plant species Type Journal Article
  Year 2018 Publication Environmental and Experimental Botany Abbreviated Journal Environmental and Experimental Botany  
  Volume 155 Issue Pages 345-359  
  Keywords Plants  
  Abstract o explore the action mode of blue light on elongation growth of bedding plants, the plant growth and morphology traits of petunia (Petunia × hybrida, ‘Duvet Red’), calibrachoa (Calibrachoa × hybrida, ‘Kabloom Deep Blue’), geranium (Pelargonium × hortorum, ‘Pinto Premium Salmon’), and marigold (Tagetes erecta, ‘Antigua Orange’) were compared under four light quality treatments: (1) R, “pure” red light (660 nm); (2) B, “pure” blue light (450 nm); (3) BR, “unpure” blue light created by mixing B with a low level of R to provide B/R ≈ 9; (4) BRF, “unpure” blue light created by adding a low level of far red light to BR with red/far red ≈ 1. Continuous (24-h) light-emitting diode lighting with either 100 or 50 μmol m−2 s−1 photosynthetic photon flux density at ≈ 23℃ was used with the above treatments. After 14–20 day of lighting treatment, B promoted elongation growth compared to R, as demonstrated by a greater canopy height, main stem length, internode length, and daily main stem extension rate. However, BR showed similar or inhibitory effects on these traits relative to R, while BRF exhibited similar promotion effects as B. The calculated phytochrome photoequilibrium, an indication of phytochrome activity, was higher for R (0.89) and BR (0.74) than for B (0.49) and BRF (0.63). Adding red (or far red) light reversed the effects of B (or BR) on elongation growth and the phytochrome photoequilibrium, suggesting that blue light promotion of elongation growth is related to the lower phytochrome activity. Also, B and BRF, when compared to R or BR, promoted elongation growth to a greater degree at 50 than 100 μmol m−2 s−1 for petunia and calibrachoa. In addition to the promoted elongation growth, B and BRF reduced side branch number, biomass allocation to side branches, leaf epinasty, leaf angle, and/or leaf chlorophyll content relative to R or BR, but increased individual leaf area, petiole length, and/or biomass allocation to main stem, which varied with different species. It suggests that the promoted elongation growth by blue light associated with lower phytochrome activity is one of shade-avoidance responses with varying sensitivity among species.  
  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 0098-8472 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1973  
Permanent link to this record
 

 
Author (up) Konkal, P.; Ganesh, C.B. url  doi
openurl 
  Title Exposure to low or high light intensity affects pituitary-testicular activity in the fish Oreochromis mossambicus Type Journal Article
  Year 2018 Publication Aquaculture Abbreviated Journal Aquaculture  
  Volume 497 Issue Pages 109-116  
  Keywords Animals  
  Abstract Light is an important factor for the successful reproduction of most fish. In this investigation, effect of different light intensities on pituitary-testis axis was studied for a period of 21 days, under normal photoperiodic regime in the tilapia Oreochromis mossambicus. The mean numbers of spermatogonia (Sg), primary spermatocytes (Ps), secondary spermatocytes (Ss), early spermatids (Est) and late spermatids (Lst) did not show significant difference between fish exposed to moderate light intensity (MLI) and initial controls or controls, whereas the mean numbers of Sg were significantly lower in fish exposed to low light intensity (LLI) compared to those of initial controls, controls and MLI groups. However, the mean numbers of Ps, Ss, Est and Lst were significantly lower in fish exposed to LLI and high light intensity (HLI) compared to those of other experimental groups. Furthermore, in the pituitary gland, weakly immunoreactive luteinizing hormone (LH) secreting cells were observed in the proximal pars distalis (PPD) region in fish exposed to LLI and HLI in contrast to the intense immunolabelling of these cells in initial controls, controls and MLI groups. The androgen receptors showed diminished immunoreactivity in the Sertoli cells along the seminiferous lobules of the testis in fish exposed to LLI and HLI, whereas the strongly immunoreactive androgen receptors were observed in the Sertoli cells in initial controls, controls and MLI groups. Taken together, these results indicate that long-term exposure to low or high light intensity light suppresses spermatogenetic process and that this inhibition is due to reduced secretory activity of LH cells in the pituitary gland and androgen secretion in the testis of the fish O. mossambicus.  
  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 0044-8486 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1974  
Permanent link to this record
 

 
Author (up) Kozaki, T.; Hidaka, Y.; Takakura, J.-Y.; Kusano, Y. url  doi
openurl 
  Title Suppression of salivary melatonin secretion under 100-Hz flickering and non-flickering blue light Type Journal Article
  Year 2018 Publication Journal of Physiological Anthropology Abbreviated Journal J Physiol Anthropol  
  Volume 37 Issue 1 Pages 23  
  Keywords Human Health  
  Abstract BACKGROUND: Bright light at night is known to suppress melatonin secretion. Novel photoreceptors named intrinsically photosensitive retinal ganglion cells (ipRGCs) are mainly responsible for projecting dark/bright information to the suprachiasmatic nucleus and thus regulating the circadian system. However, it has been shown that the amplitude of the electroretinogram of ipRGCs is considerably lower under flickering light at 100 Hz than at 1-5 Hz, suggesting that flickering light may also affect the circadian system. Therefore, in this study, we evaluated light-induced melatonin suppression under flickering and non-flickering light. METHODS: Twelve male participants between the ages of 20 and 23 years (mean +/- S.D. = 21.6 +/- 1.5 years) were exposed to three light conditions (dim, 100-Hz flickering, and non-flickering blue light) from 1:00 A.M. to 2:30 A.M., and saliva samples were obtained just before 1:00 A.M. and at 1:15, 1:30, 2:00, and 2:30 A.M. RESULTS: A repeated measures t test with Bonferroni correction showed that at 1:15 A.M., melatonin concentrations were significantly lower following exposure to non-flickering light compared with dim light, whereas there was no significant difference between the dim and 100-Hz flickering light conditions. By contrast, after 1:30 A.M., the mean melatonin concentrations were significantly lower under both 100-Hz flickering and non-flickering light than under dim light. CONCLUSION: Although melatonin suppression rate tended to be lower under 100-Hz flickering light than under non-flickering light at the initial 15 min of the light exposure, the present study suggests that 100-Hz flickering light may have the same impact on melatonin secretion as non-flickering light.  
  Address Department of Health and Nutrition Sciences, Nishikyushu University, Kanzaki, Japan  
  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 1880-6791 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30340620 Approved no  
  Call Number GFZ @ kyba @ Serial 2039  
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