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Author Stock, D. M. url  openurl
  Title LOCALIZED LIGHT SENSORY IN RELATION TO GRAZING ACTIVITY OF ECHINOMETRA MATHAEI Type Journal Article
  Year 2018 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords (up) Animals  
  Abstract This paper offers insight on the regulation of nocturnal behavior in burrowing sea urchin Echinometra mathaei of the Pacific. While it is known E. mathaei maintains nocturnal hours of activity (primarily grazing, burrowing, and locomotion), it is unknown whether this pattern follows a circadian rhythm or responds to local conditions of darkness. Varying light treatments were tested to determine potential manipulation of active behavior and explore potential for habitat destruction. Light manipulation was used to determine the role light sensory plays in the regulation of normal behavior. First utilizing gradual manipulation and later utilizing sudden manipulation to differentiate response to light stimuli. It was determined that while E. mathaei maintains nocturnal

activity via localized light sensory, manipulation of latent hours could not be significantly reproduced. It was found that while light manipulation can be responsible for simulating hours of activity, light manipulation cannot replicate latent hours. Upon exploration of predator response capability in E. mathaei following manipulation, it was found that individuals exposed to prolonged periods of artificial light had slower predation response times than individuals acclimated to a regular pattern of light exposure. These findings connect potential habitat degradation via grazing behaviors of E. mathaei to anthropogenic activity in Mo’orea, French Polynesia.
 
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  Call Number IDA @ intern @ Serial 2653  
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Author Murphy, B.A.; O’Brien, C.; Elliott, J.A. url  doi
openurl 
  Title Red light at night permits the nocturnal rise of melatonin production in horses Type Journal Article
  Year 2019 Publication The Veterinary Journal Abbreviated Journal The Veterinary Journal  
  Volume 252 Issue Pages 105360  
  Keywords (up) Animals  
  Abstract Exposure to white light at night suppresses melatonin production, impacts circadian rhythms and contributes to ill-health in humans. Human interaction with horses frequently occurs at night. We tested the hypothesis that dim red light would not suppress the nightly rise in serum melatonin levels in horses. In a crossover design, six horses were maintained for consecutive 48 h periods under a Light:Red (LR) and a Light:Dark (LD) photo-schedule. Transitions from light (>200 lux, polychromatic white light) to red (5 lux, peak wavelength 625 nm) or dark (<0.5 lux), and vice versa, coincided with ambient sunset and sunrise times. Blood was collected at 2 h intervals for 24 h during each treatment via indwelling jugular catheters. Samples were harvested for serum and stored at −20 °C until assayed for melatonin by radioimmunoassay. Repeated measures two-way ANOVA and t-tests analysed for differences in LR and LD melatonin profiles and their circadian rhythm parameters.

No time x treatment interaction or effect of treatment on serum melatonin levels were demonstrated (P > 0.05). A robust main effect of time (P<0.0001) predominated, with melatonin levels rising at night under both treatments. Statistically significant differences were not observed when LR and LD were compared for circadian rhythm measures of night time peak, area under the curve (AUC), or for times of onset (evening rise), offset (morning decline), or peak duration. Low intensity red light at night did not impact the pattern of melatonin secretion in this study and is, therefore, unlikely to impact the physiology of circadian or seasonal regulation.
 
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  Series Volume Series Issue Edition  
  ISSN 1090-0233 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2656  
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Author Walbeek, T.J.; Harrison, E.M.; Soler, R.R.; Gorman, M.R. url  doi
openurl 
  Title Enhanced Circadian Entrainment in Mice and Its Utility under Human Shiftwork Schedules Type Journal Article
  Year 2019 Publication Clocks & Sleep Abbreviated Journal Clocks & Sleep  
  Volume 1 Issue 3 Pages 394-413  
  Keywords (up) Animals  
  Abstract The circadian system is generally considered to be incapable of adjusting to rapid changes in sleep/work demands. In shiftworkers this leads to chronic circadian disruption and sleep loss, which together predict underperformance at work and negative health consequences. Two distinct experimental protocols have been proposed to increase circadian flexibility in rodents using dim light at night: rhythm bifurcation and T-cycle (i.e., day length) entrainment. Successful translation of such protocols to human shiftworkers could facilitate alignment of internal time with external demands. To assess entrainment flexibility following bifurcation and exposure to T-cycles, mice in Study 1 were repeatedly phase-shifted. Mice from experimental conditions rapidly phase-shifted their activity, while control mice showed expected transient misalignment. In Study 2 and 3, mice followed a several weeks-long intervention designed to model a modified DuPont or Continental shiftwork schedule, respectively. For both schedules, bifurcation and nocturnal dim lighting reduced circadian misalignment. Together, these studies demonstrate proof of concept that mammalian circadian systems can be rendered sufficiently flexible to adapt to multiple, rapidly changing shiftwork schedules. Flexible adaptation to exotic light-dark cycles likely relies on entrainment mechanisms that are distinct from traditional entrainment.  
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  ISSN 2624-5175 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2661  
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Author Renthlei, Z.; Trivedi, A.K. url  doi
openurl 
  Title Effect of urban environment on pineal machinery and clock genes expression of tree sparrow (Passer montanus) Type Journal Article
  Year 2019 Publication Environmental Pollution Abbreviated Journal Environmental Pollution  
  Volume 255 Issue Pages 113278  
  Keywords (up) Animals  
  Abstract Increasing urbanisation is altering the physiology of wild animals and the mechanisms involved are largely unknown. We hypothesised that altering the physiology of urban organisms is due to the effect of extra light at night on the circadian clock by modulating the expression of pineal machinery and clock genes. Two experiments were performed. In Experiment 1, immediately after being procured from their respective sites (urban and rural sites), birds were released individually in LLdim light conditions. Circadian rhythm period, activity duration, and total activity count were calculated and did not differ between urban and rural birds. In Experiment 2, birds (from urban and rural habitats) were sampled at six time points at regular 4-h intervals, beginning 1 h after sunrise. We measured daily variations in plasma melatonin levels. We also analysed the expression levels of Aanat, Mel1A and Mel1B as an indicator of melatonin biosynthesis and action machinery. Clock and clock-controlled genes (Bmal1, Clock, Per2, Per3, Cry1 and Npas2) were studied in the hypothalamus, the pineal gland, and retina to investigate the effects of urban habitats on the circadian clock. Our results show that there is a lower expression of Aanat in the pineal gland and relatively low plasma melatonin levels in urban birds. Further, clock genes are also differentially expressed in all three central tissues of urban birds. We propose that alterations in the melatonin biosynthesis machinery and the expression of clock genes could result in miscalculations in the internal timing of the organism, with environmental timings leading to altered physiology in urban wild animals.  
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  Series Volume Series Issue Edition  
  ISSN 0269-7491 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2682  
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Author Frost, S.W. openurl 
  Title Insects taken in light traps at the Archbold Biological Station, Highlands County, Florida Type Journal Article
  Year 1964 Publication Florida Entomologist Abbreviated Journal  
  Volume 47 Issue 2 Pages 129-161  
  Keywords (up) Animals  
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  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2732  
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