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Author Kozaki, Tomoaki; Taketomi, Ryunosuke; Hidaka ,Yuki; Ida, Nagisa; Yasuda, Takeo url  doi
openurl 
  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 (down) 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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  Call Number LoNNe @ kyba @ Serial 1785  
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Author 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 (down) 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  
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  Language English Summary Language Original Title  
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  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 Lee, S.; Kakitsuba, N.; Katsuura, T. url  doi
openurl 
  Title Do green-blocking glasses enhance the nonvisual effects of white polychromatic light? Type Journal Article
  Year 2018 Publication Journal of Physiological Anthropology Abbreviated Journal J Physiol Anthropol  
  Volume (down) 37 Issue 1 Pages 29  
  Keywords Human Health; Vision  
  Abstract BACKGROUND: It is well known that light containing the blue component stimulates the intrinsically photosensitive retinal ganglion cells (ipRGCs) and plays a role in melatonin suppression and pupillary constriction. In our previous studies, we verified that simultaneous exposure to blue and green light resulted in less pupillary constriction than blue light exposure. Hence, we hypothesized that the nonvisual effects of polychromatic white light might be increased by blocking the green component. Therefore, we conducted an experiment using optical filters that blocked blue or green component and examined the nonvisual effects of these lights on pupillary constriction and electroencephalogram power spectra. METHODS: Ten healthy young males participated in this study. The participant sat on a chair with his eyes facing an integrating sphere. After 10 min of light adaptation, the participant's left eye was exposed to white pulsed light (1000 lx; pulse width 2.5 ms) every 10 s with a blue-blocking glasses, a green-blocking glasses, or control glasses (no lens), and pupillary constriction was measured. Then, after rest for 10 min, the participant was exposed a continuous white light of 1000 lx with a blue- or green-blocking glasses or control glasses and electroencephalogram was measured. RESULTS: Pupillary constriction with the blue-blocking glasses was significantly less than that observed with the green-blocking glasses. Furthermore, pupillary constriction under the green-blocking glasses was significantly greater than that observed with the control glasses. CONCLUSIONS: A reduction in the green component of light facilitated pupillary constriction. Thus, the effects of polychromatic white light containing blue and green components on ipRGCs are apparently increased by removing the green component.  
  Address Graduate School of Engineering, Chiba University, Chiba, Japan  
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  ISSN 1880-6791 ISBN Medium  
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  Notes PMID:30563575; PMCID:PMC6299521 Approved no  
  Call Number GFZ @ kyba @ Serial 2153  
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Author Morelli, F.; Mikula, P.; Benedetti, Y.; Bussière, R.; Tryjanowski, P. url  doi
openurl 
  Title Cemeteries support avian diversity likewise urban parks in European cities: Assessing taxonomic, evolutionary and functional diversity Type Journal Article
  Year 2018 Publication Urban Forestry & Urban Greening Abbreviated Journal Urban Forestry & Urban Greening  
  Volume (down) 36 Issue Pages 90-99  
  Keywords Animals; Ecology  
  Abstract The aim of this study was to explore different components of avian diversity in two types of urban green areas, parks and cemeteries, in four European countries in relation to environmental characteristics. We studied bird species richness, functional diversity and evolutionary distinctiveness in 79 parks and 90 cemeteries located in four European countries: the Czech Republic, France, Italy and Poland.

First, we found no significant differences between cemeteries and parks in bird diversity. However, in both parks and cemeteries, only: two community metrics were affected by different environmental characteristics, including local vegetation structure and presence of human-related structures. Species richness was positively correlated with tree coverage and site size, functional diversity was unrelated to any of the measured variables, while the mean evolutionary distinctiveness score was positively correlated with tree coverage and negatively associated with the coverage of flowerbeds and number of street lamps.

Our findings can be useful for urban planning: by increasing tree coverage and site size it is possible to increase both taxonomic richness and evolutionary uniqueness of bird communities. In both parks and cemeteries, the potential association between light pollution and bird species richness was negligible. We also identified some thresholds where bird diversity was higher. Bird species richness was maximized in parks/cemeteries larger than 1.4 ha, with grass coverage lower than 65%. The evolutionary uniqueness of bird communities was higher in areas with tree coverage higher than 45%. In conclusion, the findings of this study provide evidence that cemeteries work similarly than urban parks supporting avian diversity.
 
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  ISSN 1618-8667 ISBN Medium  
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  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2141  
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Author Madahi, P.-G.; Ivan, O.; Adriana, B.; Diana, O.; Carolina, E. url  doi
openurl 
  Title Constant light during lactation programs circadian and metabolic systems Type Journal Article
  Year 2018 Publication Chronobiology International Abbreviated Journal Chronobiol Int  
  Volume (down) 35 Issue 8 Pages 1153-1167  
  Keywords Animals  
  Abstract Exposure to light at night is a disruptive condition for the adult circadian system, leading to arrhythmicity in nocturnal rodents. Circadian disruption is a risk factor for developing physiological and behavioral alterations, including weight gain and metabolic disease. During early stages of development, the circadian system undergoes a critical period of adjustment, and it is especially vulnerable to altered lighting conditions that may program its function, leading to long-term effects. We hypothesized that during lactation a disrupted light-dark cycle due to light at night may disrupt the circadian system and in the long term induce metabolic disorders. Here we explored in pups, short- and long-term effects of constant light (LL) during lactation. In the short term, LL caused a loss of rhythmicity and a reduction in the immunopositive cells of VIP, AVP, and PER1 in the suprachiasmatic nucleus (SCN). In the short term, the affection on the circadian clock in the pups resulted in body weight gain, loss of daily rhythms in general activity, plasma glucose and triglycerides (TG). Importantly, the DD conditions during development also induced altered daily rhythms in general activity and in the SCN. Exposure to LD conditions after lactation did not restore rhythmicity in the SCN, and the number of immunopositve cells to VIP, AVP, and PER1 remained reduced. In the long term, daily rhythmicity in general activity was restored; however, daily rhythms in glucose and TG remained disrupted, and daily mean levels of TG were significantly increased. Present results point out the programming role played by the LD cycle during early development in the function of the circadian system and on metabolism. This study points out the risk represented by exposure to an altered light-dark cycle during early stages of development. ABBREVIATIONS: AVP: arginine vasopressin peptide; CRY: cryptochrome; DD: constant darkness; DM: dorsomedial; LD: light-dark cycle; LL: constant light; NICUs: neonatal intensive care units; P: postnatal days; PER: period; S.E.M.: standard error of the mean; SCN: suprachiasmatic nucleus; TG: triglycerides; VIP: vasointestinal peptide; VL: ventrolateral; ZT: zeitgeber time.  
  Address a Facultad de Medicina , Universidad Nacional Autonoma de Mexico, UNAM , Mexico City , Mexico  
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  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:29688088 Approved no  
  Call Number GFZ @ kyba @ Serial 1884  
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