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Author Flores, D.E.F.L.; Oda, G.A. url  doi
openurl 
  Title Novel Light/Dark Regimens with Minimum Light Promote Circadian Disruption: Simulations with a Model Oscillator Type Journal Article
  Year 2018 Publication Journal of Biological Rhythms Abbreviated Journal J Biol Rhythms  
  Volume in press Issue Pages  
  Keywords Animals  
  Abstract (up) Artificial lab manipulation of LD cycles has enabled simulations of the disruptive conditions found in modern human societies, such as jet-lag, night-work and light at night. New techniques using animal models have been developed, and these can greatly improve our understanding of circadian disruption. Some of these techniques, such as in vivo bioluminescence assays, require minimum external light. This requirement is challenging because the usual lighting protocols applied in circadian desynchronization experiments rely on considerable light input. Here, we present a novel LD regimen that can disrupt circadian rhythms with little light per day, based on computer simulations of a model limit-cycle oscillator. The model predicts that a single light pulse per day has the potential to disturb rhythmicity when pulse times are randomly distributed within an interval. Counterintuitively, the rhythm still preserves an underlying 24-h periodicity when this interval is as large as 14 h, indicating that day/night cues are still detectable. Only when pulses are spread throughout the whole 24-h day does the rhythm lose any day-to-day period correlation. In addition, the model also reveals that stronger pulses of brighter light should exacerbate the disrupting effects. We propose the use of this LD schedule-which would be compatible with the requirements of in vivo bioluminescence assays-to help understand circadian disruption and associated illnesses.  
  Address Instituto de Biociencias, Universidade de Sao Paulo, Sao Paulo, SP, Brazil  
  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 0748-7304 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30595077 Approved no  
  Call Number GFZ @ kyba @ Serial 2146  
Permanent link to this record
 

 
Author Lundberg, L.; Sienkiewicz, Z.; Anthony, D.C.; Broom, K.A. url  doi
openurl 
  Title Effects of 50 Hz magnetic fields on circadian rhythm control in mice Type Journal Article
  Year 2019 Publication Bioelectromagnetics Abbreviated Journal Bioelectromagnetics  
  Volume 40 Issue 4 Pages 250-259  
  Keywords Animals; mouse models; magnetic fields  
  Abstract (up) Artificial light and power frequency magnetic fields are ubiquitous in the built environment. Light is a potent zeitgeber but it is unclear whether power frequency magnetic fields can influence circadian rhythm control. To study this possibility, 8-12-week-old male C57BL/6J mice were exposed for 30 min starting at zeitgeber time 14 (ZT14, 2 h into the dark period of the day) to 50 Hz magnetic fields at 580 muT using a pair of Helmholtz coils and/or a blue LED light at 700 lux or neither. Our experiments revealed an acute adrenal response to blue light, in terms of increased adrenal per1 gene expression, increased serum corticosterone levels, increased time spent sleeping, and decreased locomotor activity (in all cases, P < 0.0001) compared to an unexposed control group. There appeared to be no modulating effect of the magnetic fields on the response to light, and there was also no effect of the magnetic fields alone (in both cases, P > 0.05) except for a decrease in locomotor activity (P < 0.03). Gene expression of the cryptochromes cry1 and cry2 in the adrenals, liver, and hippocampus was also not affected by exposures (in all cases, P > 0.05). In conclusion, these results suggest that 50 Hz magnetic fields do not significantly affect the acute light response to a degree that can be detected in the adrenal response.  
  Address Public Health England, Chilton, United Kingdom;  
  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 0197-8462 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30945762 Approved no  
  Call Number GFZ @ kyba @ Serial 2289  
Permanent link to this record
 

 
Author Peregrym, M., Kónya E. P., & Vasyliuk, O. url  doi
openurl 
  Title The impact of artificial light at night (ALAN) on the National Nature Parks, Biosphere and Naturе Reserves of the Steppe Zone and Crimean Mountains within Ukraine Type Journal Article
  Year 2018 Publication Palaearctic Grasslands Abbreviated Journal  
  Volume Issue Pages  
  Keywords Skyglow; Conservation  
  Abstract (up) Artificial light at night (ALAN) and sky glow are a recognized anthropogenic pressure, but the consequences of this pressure on protected areas within Ukraine are unclear. This research attempted to estimate the level of light pollution on the protected territories of the National Nature Parks (NNPs), Biosphere and Nature Reserves in the Steppe Zone and Crimea Mountains of Ukraine. Kmz layers of

these protected territories and the New World Atlas of Artificial Sky Brightness, through Google Earth Pro, were used to calculate the level of artificial sky brightness for 15 NNPs, three Biosphere Reserves and 10 Nature Reserves. The results show that even some of the most protected areas within the Steppe Zone and Crimean Mountains are impacted by ALAN. Of the studied protected areas 44.2% have a natural dark night sky, 40.1% have artificial brightness ranging between 8 and 16%, and the remainder (15.7%) are polluted with an artificial brightness greater than 16%. Areas with light pollution greater than 16% are often situated near big cities or industrial centers. It was noted that light pollution levels were not taken into account during the creation of any protected areas within Ukraine.
 
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  Notes Approved no  
  Call Number IDA @ intern @ Serial 2310  
Permanent link to this record
 

 
Author Grunst, M.L.; Raap, T.; Grunst, A.S.; Pinxten, R.; Parenteau, C.; Angelier, F.; Eens, M. url  doi
openurl 
  Title Early-life exposure to artificial light at night elevates physiological stress in free-living songbirds Type Journal Article
  Year 2020 Publication Environmental Pollution Abbreviated Journal Environmental Pollution  
  Volume Issue Pages in press  
  Keywords Animals  
  Abstract (up) Artificial light at night (ALAN) can disrupt adaptive patterns of physiology and behavior that promote high fitness, resulting in physiological stress and elevation of steroid glucocorticoids (corticosterone, CORT in birds). Elevated CORT may have particularly profound effects early in life, with the potential for enduring effects that persist into adulthood. Research on the consequences of early-life exposure to ALAN remains limited, especially outside of the laboratory, and the effects of early-life light exposure on CORT concentrations in wild nestling birds remain to be elucidated. We used an experimental setup to test the hypothesis that ALAN elevates CORT concentrations in developing free-living birds, by exposing nestling great tits (Parus major) to ALAN inside nest boxes. We measured CORT in feathers grown over the timeframe of the experiment (7 nights), such that CORT concentrations represent an integrative metric of hormone release over the period of nocturnal light exposure, and of development. We also assessed the relationships between feather CORT concentrations, body condition, nestling size rank and fledging success. In addition, we evaluated the relationship between feather CORT concentrations and telomere length. Nestlings exposed to ALAN had higher feather CORT concentrations than control nestlings, and nestlings in poorer body condition and smaller brood members also had higher CORT. On the other hand, telomere length, fledging success, and recruitment rate were not significantly associated with light exposure or feather CORT concentrations. Results indicate that exposure to ALAN elevates CORT concentrations in nestlings, which may reflect physiological stress. In addition, the organizational effects of CORT are known to be substantial. Thus, despite the lack of effect on telomere length and survivorship, elevated CORT concentrations in nestlings exposed to ALAN may have subsequent impacts on later-life fitness and stress sensitivity.  
  Address  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0269-7491 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2796  
Permanent link to this record
 

 
Author Franziska, K.; Franz, H.; Werner, K. url  doi
openurl 
  Title Can skyglow reduce nocturnal melatonin concentrations in Eurasian perch? Type Journal Article
  Year 2020 Publication Environmental Pollution Abbreviated Journal Environmental Pollution  
  Volume in press Issue Pages 114324  
  Keywords Animals  
  Abstract (up) Artificial light at night (ALAN) changes the natural rhythm of light and darkness and can impair the biorhythms of animals, for example the nocturnal melatonin production of vertebrates, which serves as a proxy for daily physiological rhythms. Freshwater fish are exposed to ALAN in large urban and suburban areas in the form of direct light or in the form of skyglow, a diffuse brightening of the night sky through the scattered light reflected by clouds, atmospheric molecules, and particles in the air. However, investigations on the sensitivity of melatonin production of fish towards low intensities of ALAN in the range of typical skyglow are rare. Therefore, we exposed Eurasian perch (Perca fluviatilis) to nocturnal illumination levels of 0.01 lx, 0.1 lx and 1 lx and a control group with dark nights and daylight intensities of 2900 lx in all groups. After ten days of exposure to the experimental conditions, tank water was non-invasively sampled every 3 h over a 24 h period and melatonin was measured by ELISA. Melatonin was gradually reduced in all treatments with increasing intensity of ALAN whereas rhythmicity was maintained in all treatment groups although at 1 lx not all evaluated parameters confirmed rhythmicity. These results show a high sensitivity of Eurasian perch towards ALAN indicating that low light intensities of 0.01 lx and 0.1 lx as they occur in urban and suburban areas in the form of skyglow can affect the physiology of Eurasian perch. Furthermore, we highlight how this may impact perch in their sensitivity towards lunar rhythms and the role of skyglow for biorhythms of temperate freshwater fish.  
  Address  
  Corporate Author Thesis  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0269-7491 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2847  
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