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Author (up) Kong, Y.; Stasiak, M.; Dixon, M.A.; Zheng, Y.
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.
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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
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Author (up) Konkal, P.; Ganesh, C.B.
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.
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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
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Author (up) Kozaki, T.; Hidaka, Y.; Takakura, J.-Y.; Kusano, Y.
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
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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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Author (up) Kozaki, Tomoaki; Taketomi, Ryunosuke; Hidaka ,Yuki; Ida, Nagisa; Yasuda, Takeo
Title Preventive Effect of Morning Bluish LED Light on Light-induced Melatonin Suppression at Night Type Journal Article
Year 2018 Publication Journal of Science and Technology in Lighting Abbreviated Journal
Volume 41 Issue Pages 206-210
Keywords Human Health
Abstract Bright nocturnal light has been known to suppress melatonin secretion. However, bright light exposure during daytime might reduce light-induced melatonin suppression (LIMS) at night. This study aims to evaluate the effect of high correlated color temperature LED light during daytime on LIMS. Male participants were exposed to different light conditions for 3 h in the morning (09:00â??12:00). The light conditions were dim light (<10 lx), 125 lx high correlated color temperature (CCT) LED light, and 250 lx high CCT LED light. The subjects were then exposed to bright light (white light, 300 lx) for 1.5 h at night (01:00â??02:30). Saliva samples were taken before (01:00) and after (02:30) exposure for evaluation of melatonin secretion. There were no significant differences in melatonin secretion before and after night-time light exposure on the 125 lx and 250 lx morning light conditions. Since these light intensities were almost equal to those in our previous study, the high CCT LED light might be appropriate for certain work places (e.g., hospitals and underground spaces), contributing to the reduction of our health risk and also saving energy.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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ISSN ISBN Medium
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Notes Approved no
Call Number LoNNe @ kyba @ Serial 1785
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Author (up) Kuffer, M.; Pfeffer, K.; Sliuzas, R.; Taubenbock, H.; Baud, I.; van Maarseveen, M.
Title Capturing the Urban Divide in Nighttime Light Images From the International Space Station Type Journal Article
Year 2018 Publication IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing Abbreviated Journal IEEE J. Sel. Top. Appl. Earth Observations Remote Sensing
Volume 11 Issue 8 Pages 2578-2586
Keywords Remote Sensing
Abstract Earlier studies utilizing coarse resolution DMSP-OLS nighttime light (NTL) imagery suggest a negative correlation between the amount of NTL and urban deprivation. The International Space Station (ISS) NTL images offer higher resolution images compared to DMSP-OLS or VIIRS images, allowing an analysis of intraurban NTL variations. The aim of this study is to examine the capacity of ISS images for analyzing the intraurban divide. NTL images of four cities (one African, two Asian, and one South American) have been processed and analyzed. The results show that deprived areas are generally the darker spots of built-up areas within cities, illustrating the urban divide in terms of access to street lighting. However, differences exist between cities: Deprived areas in the African city (Dar es Salaam) generally feature lower NTL emissions compared to the examined cities in South America (Belo Horizonte) and Asia (Mumbai and Ahmedabad). Beyond, variations exist in NTL emissions across deprived areas within cities. Deprived areas at the periphery show less NTL compared to central areas. Edges of deprived areas have higher NTL emissions compared to internal areas. NTL emission differences between types of deprived areas were detected. The correlation between ISS NTL images and population densities is weak; this can be explained by densely built-up deprived areas having less NTL compared to lower density formal areas. Our findings show ISS data complement other data to capture the urban divide between deprived and better-off areas and the need to consider socioeconomic conditions in estimating populations.
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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 1939-1404 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2178
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