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Author Youngstedt, S.D.; Elliott, J.A.; Kripke, D.F. url  doi
openurl 
  Title Human Circadian Phase-Response Curves for Exercise Type Journal Article
  Year 2019 Publication (down) The Journal of Physiology Abbreviated Journal J Physiol  
  Volume in press Issue Pages  
  Keywords Human Health  
  Abstract KEY POINTS: Exercise elicits circadian phase-shifting effects, but additional information is needed. The phase-response curve describing the magnitude and direction of circadian rhythm phase shifts depending on the time of the zeigeber (time cue) stimulus is the most fundamental chronobiological tool for alleviating circadian misalignment and related morbidity. 51 older and 48 young adults followed a circadian rhythms measurement protocol for up to 5.5 days, and performed 1 h of moderate treadmill exercise for 3 consecutive days at one of 8 times of day/night. Temporal changes in the phase of 6-sulphatoxymelatonin (aMT6s) were measured from evening onset, cosine acrophase, morning offset, and duration of excretion, establishing significant PRCs for aMT6 onset and acrophase with large phase delays from 7-10 PM and large phase advances at both 7 AM and 1-4 PM. Along with known synergism with bright light, the above PRCs with a second phase advance region (afternoon) could support both practical and clinical applications. ABSTRACT: Although bright light is regarded as the primary circadian zeitgeber, its limitations support exploring alternative zeitgebers. Exercise elicits significant circadian phase-shifting effects, but fundamental information regarding these effects is needed. The primary aim of this study was to establish phase-response curves (PRC) documenting the size and direction of phase shifts in relation to the circadian time of exercise. Aerobically fit older (n = 51, 59-75 y) and young adults (n = 48, 18-30 y) followed a 90-min laboratory ultra-short sleep wake cycle (60 min wake/30 min sleep) for up to 5 (1/2) days. At the same clock time on three consecutive days, each participant performed 60 min of moderate treadmill exercise (65-75% of heart rate reserve) at one of 8 times of day/night. To describe PRCs, phase shifts were measured for the cosine-fitted acrophase of urinary 6-sulphatoxymelatonin (aMT6s), as well as for the evening rise, morning decline, and change in duration of aMT6s excretion. Significant PRCs were found for aMT6s acrophase, onset and duration, with peak phase advances corresponding to clock times of 7 AM and 1PM-4PM, delays from 7 PM-10 PM, and minimal shifts around 4 PM and 2 AM. There were no significant age or sex differences. The amplitudes of the aMT6s onset and acrophase PRCs are comparable to expectations for bright light of equal duration. The phase advance to afternoon exercise and the exercise-induced PRC for change in aMT6s duration are novel findings. The results support further research exploring additive phase shifting effects of bright light and exercise and health benefits. This article is protected by copyright. All rights reserved.  
  Address Department of Psychiatry, University of California, San Diego, CA  
  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 0022-3751 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30784068 Approved no  
  Call Number GFZ @ kyba @ Serial 2230  
Permanent link to this record
 

 
Author Clark, N.A. url  doi
openurl 
  Title The Rate of Reproduction of Lemna Major as a Function of Intensity and Duration of Light Type Journal Article
  Year 1924 Publication (down) The Journal of Physical Chemistry Abbreviated Journal J. Phys. Chem.  
  Volume 29 Issue 8 Pages 935-941  
  Keywords Plants  
  Abstract  
  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 0092-7325 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2374  
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Author Foster, J.J.; Kirwan, J.D.; El Jundi, B.; Smolka, J.; Khaldy, L.; Baird, E.; Byrne, M.J.; Nilsson, D.-E.; Johnsen, S.; Dacke, M. url  doi
openurl 
  Title Orienting to polarized light at night – matching lunar skylight to performance in a nocturnal beetle Type Journal Article
  Year 2019 Publication (down) The Journal of Experimental Biology Abbreviated Journal J Exp Biol  
  Volume 222 Issue Pt 2 Pages  
  Keywords Animals; Natural skylight  
  Abstract For polarized light to inform behaviour, the typical range of degrees of polarization observable in the animal's natural environment must be above the threshold for detection and interpretation. Here, we present the first investigation of the degree of linear polarization threshold for orientation behaviour in a nocturnal species, with specific reference to the range of degrees of polarization measured in the night sky. An effect of lunar phase on the degree of polarization of skylight was found, with smaller illuminated fractions of the moon's surface corresponding to lower degrees of polarization in the night sky. We found that the South African dung beetle Escarabaeus satyrus can orient to polarized light for a range of degrees of polarization similar to that observed in diurnal insects, reaching a lower threshold between 0.04 and 0.32, possibly as low as 0.11. For degrees of polarization lower than 0.23, as measured on a crescent moon night, orientation performance was considerably weaker than that observed for completely linearly polarized stimuli, but was nonetheless stronger than in the absence of polarized light.  
  Address Lund Vision Group, Department of Biology, Lund University, Solvegatan 35, 223 62 Lund, Sweden  
  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 0022-0949 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30530838 Approved no  
  Call Number GFZ @ kyba @ Serial 2599  
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Author Wittenbrink, N.; Ananthasubramaniam, B.; Munch, M.; Koller, B.; Maier, B.; Weschke, C.; Bes, F.; de Zeeuw, J.; Nowozin, C.; Wahnschaffe, A.; Wisniewski, S.; Zaleska, M.; Bartok, O.; Ashwal-Fluss, R.; Lammert, H.; Herzel, H.; Hummel, M.; Kadener, S.; Kunz, D.; Kramer, A. url  doi
openurl 
  Title High-accuracy determination of internal circadian time from a single blood sample Type Journal Article
  Year 2018 Publication (down) The Journal of Clinical Investigation Abbreviated Journal J Clin Invest  
  Volume 128 Issue 9 Pages 3826-3839  
  Keywords Human Health  
  Abstract BACKGROUND: The circadian clock is a fundamental and pervasive biological program that coordinates 24-hour rhythms in physiology, metabolism, and behavior, and it is essential to health. Whereas therapy adapted to time of day is increasingly reported to be highly successful, it needs to be personalized, since internal circadian time is different for each individual. In addition, internal time is not a stable trait, but is influenced by many factors, including genetic predisposition, age, sex, environmental light levels, and season. An easy and convenient diagnostic tool is currently missing. METHODS: To establish a validated test, we followed a 3-stage biomarker development strategy: (a) using circadian transcriptomics of blood monocytes from 12 individuals in a constant routine protocol combined with machine learning approaches, we identified biomarkers for internal time; and these biomarkers (b) were migrated to a clinically relevant gene expression profiling platform (NanoString) and (c) were externally validated using an independent study with 28 early or late chronotypes. RESULTS: We developed a highly accurate and simple assay (BodyTime) to estimate the internal circadian time in humans from a single blood sample. Our assay needs only a small set of blood-based transcript biomarkers and is as accurate as the current gold standard method, dim-light melatonin onset, at smaller monetary, time, and sample-number cost. CONCLUSION: The BodyTime assay provides a new diagnostic tool for personalization of health care according to the patient's circadian clock. FUNDING: This study was supported by the Bundesministerium fur Bildung und Forschung, Germany (FKZ: 13N13160 and 13N13162) and Intellux GmbH, Germany.  
  Address Charite Universitatsmedizin Berlin, corporate member of Freie Universitat Berlin, Humboldt-Universitat zu Berlin, and Berlin Institute of Health, Laboratory of Chronobiology, Berlin, Germany  
  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 0021-9738 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:29953415; PMCID:PMC6118629 Approved no  
  Call Number GFZ @ kyba @ Serial 2194  
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Author Cabrera-Cruz, S.A.; Smolinsky, J.A.; McCarthy, K.P.; Buler, J.J. url  doi
openurl 
  Title Urban areas affect flight altitudes of nocturnally migrating birds Type Journal Article
  Year 2019 Publication (down) The Journal of Animal Ecology Abbreviated Journal J Anim Ecol  
  Volume in press Issue Pages  
  Keywords Remote Sensing; Animals; Aeroecology; bird migration; flight altitude; light pollution; radar; urbanization  
  Abstract 1.Urban areas affect terrestrial ecological processes and local weather, but we know little about their effect on aerial ecological processes. 2.Here, we identify urban from non-urban areas based on the intensity of artificial light at night (ALAN) in the landscape, and, along with weather covariates, evaluate the effect of urbanization on flight altitudes of nocturnally migrating birds. 3.Birds are attracted to ALAN, hence we predicted that altitudes would be lower over urban than over non-urban areas. However, other factors associated with urbanization may also affect flight altitudes. For example, surface temperature and terrain roughness are higher in urban areas, increasing air turbulence, height of the boundary layer, and affecting local winds. 4.We used data from nine weather surveillance radars in the eastern US to estimate altitudes at five quantiles of the vertical distribution of birds migrating at night over urban and non-urban areas during five consecutive spring and autumn migration seasons. We fit generalized linear mixed models by season for each of the five quantiles of bird flight altitude and their differences between urban and non-urban areas. 5.After controlling for other environmental variables and contrary to our prediction, we found that birds generally fly higher over urban areas compared to rural areas in spring, and marginally higher at the mid layers of the vertical distribution in autumn. We also identified a small interaction effect between urbanization and crosswind speed, and between urbanization and surface air temperature, on flight altitudes. We also found that the difference in flight altitudes of nocturnally migrating birds between urban and non-urban areas varied among radars and seasons, but were consistently higher over urban areas throughout the years sampled. 6.Our results suggest that the effects of urbanization on wildlife extend into the aerosphere, and are complex, stressing the need of understanding the influence of anthropogenic factors on airspace habitat. This article is protected by copyright. All rights reserved.  
  Address Department of Entomology and Wildlife Ecology, University of Delaware, Delaware, 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 0021-8790 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:31330569 Approved no  
  Call Number GFZ @ kyba @ Serial 2604  
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