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Author Arendt, J.; Middleton, B. url  doi
openurl 
  Title Human seasonal and circadian studies in Antarctica (Halley, 75 degrees S) Type Journal Article
  Year 2018 Publication (up) General and Comparative Endocrinology Abbreviated Journal Gen Comp Endocrinol  
  Volume 258 Issue Pages 250-258  
  Keywords Human Activities; Acclimatization/*physiology; Actigraphy; Adult; Antarctic Regions; Behavior/*physiology; Circadian Rhythm/*physiology; Darkness; Female; Heart Rate/physiology; Humans; Libido; Light; Male; Melatonin/blood; Photoperiod; *Seasons; Sleep/physiology; Young Adult; *Antarctica; *Circadian; *Light; *Melatonin; *Seasonal  
  Abstract Living for extended periods in Antarctica exposes base personnel to extremes of daylength (photoperiod) and temperature. At the British Antarctic Survey base of Halley, 75 degrees S, the sun does not rise for 110 d in the winter and does not set for 100 d in summer. Photoperiod is the major time cue governing the timing of seasonal events such as reproduction in many species. The neuroendocrine signal providing photoperiodic information to body physiology is the duration of melatonin secretion which reflects the length of the night: longer in the short days of winter and shorter in summer. Light of sufficient intensity and spectral composition serves to suppress production of melatonin and to set the circadian timing and the duration of the rhythm. In humans early observations suggested that bright (>2000 lux) white light was needed to suppress melatonin completely. Shortly thereafter winter depression (Seasonal Affective Disorder or SAD) was described, and its successful treatment by an artificial summer photoperiod of bright white light, sufficient to shorten melatonin production. At Halley dim artificial light intensity during winter was measured, until 2003, at a maximum of approximately 500 lux in winter. Thus a strong seasonal and circadian time cue was absent. It seemed likely that winter depression would be common in the extended period of winter darkness and could be treated with an artificial summer photoperiod. These observations, and predictions, inspired a long series of studies regarding human seasonal and circadian status, and the effects of light treatment, in a small overwintering, isolated community, living in the same conditions for many months at Halley. We found little evidence of SAD, or change in duration of melatonin production with season. However the timing of the melatonin rhythm itself, and/or that of its metabolite 6-sulphatoxymelatonin (aMT6s), was used as a primary marker of seasonal, circadian and treatment changes. A substantial phase delay of melatonin in winter was advanced to summer phase by a two pulse 'skeleton' bright white light treatment. Subsequently a single morning pulse of bright white light was effective with regard to circadian phase and improved daytime performance. The circadian delay evidenced by melatonin was accompanied by delayed sleep (logs and actigraphy): poor sleep is a common complaint in Polar regions. Appropriate extra artificial light, both standard white, and blue enriched, present throughout the day, effectively countered delay in sleep timing and the aMT6s rhythm. The most important factor appeared to be the maximum light experienced. Another manifestation of the winter was a decline in self-rated libido (men only on base at this time). Women on the base showed lower aspects of physical and mental health compared to men. Free-running rhythms were seen in some subjects following night shift, but were rarely found at other times, probably because this base has strongly scheduled activity and leisure time. Complete circadian adaptation during a week of night shift, also seen in a similar situation on North Sea oil rigs, led to problems readapting back to day shift in winter, compared to summer. Here again timed light treatment was used to address the problem. Sleep, alertness and waking performance are critically dependent on optimum circadian phase. Circadian desynchrony is associated with increased risk of major disease in shift workers. These studies provide some groundwork for countering/avoiding circadian desynchrony in rather extreme conditions.  
  Address Biochemistry and Physiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK. Electronic address: b.middleton@surrey.ac.uk  
  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 0016-6480 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:28526480 Approved no  
  Call Number IDA @ john @ Serial 2248  
Permanent link to this record
 

 
Author Shor, E.; Potavskaya, R.; Kurtz, A.; Paik, I.; Huq, E.; Green, R. url  doi
openurl 
  Title PIF-mediated sucrose regulation of the circadian oscillator is light quality and temperature dependent Type Journal Article
  Year 2018 Publication (up) Genes Abbreviated Journal Genes (Basel)  
  Volume 9 Issue 12 Pages  
  Keywords Plants  
  Abstract Studies are increasingly showing that metabolic and circadian (~24 h) pathways are strongly interconnected, with the circadian system regulating the metabolic state of the cell, and metabolic products feeding back to entrain the oscillator. In plants, probably the most significant impact of the circadian system on metabolism is in its reciprocal regulation of photosynthesis; however, the pathways by which this occurs are still poorly understood. We have previously shown that members of the basic helix-loop-helix (bHLH) transcription factor PHYTOCHROME INTERACTING FACTOR (PIF) family are involved in the photosynthate entrainment of the circadian oscillator. In this paper, using Arabidopsis mutants and overexpression lines, we examine how temperature and light quality affect PIF-mediated sucrose signaling to the oscillator and examine the contributions of individual PIF members. Our results also show that the quality of light is important for PIF signaling, with red and blue lights having the opposite effects, and that temperature affects PIF-mediated sucrose signaling. We propose the light sensitivity of PIF-mediated sucrose entrainment of the oscillator may be important in enabling plants to distinguish between sucrose produced de novo from photosynthesis during the day and the sucrose products of starch degradation at the end of the night.  
  Address Department of Plant and Environmental Sciences, Institute for Life Sciences, Edmond J. Safra Campus, Givat Ram, Hebrew University, Jerusalem 91904, Israel. rgreen@mail.huji.ac.il  
  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 2073-4425 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30551669; PMCID:PMC6316277 Approved no  
  Call Number GFZ @ kyba @ Serial 2155  
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Author Hiltunen, A. P., Kumpula, T., &Tykkyläinen, M. url  openurl
  Title Yövalaistuksen ja valopäästöjen alueellinen jakautuminen Type Journal Article
  Year 2018 Publication (up) Geoinformatiikka Yhteiskunnassa Abbreviated Journal  
  Volume 130 Issue 4 Pages  
  Keywords Remote Sensing  
  Abstract Remotely-sensed night-time lights (NTL) reveal the occurrence of human development while excessive light emissions cause ecological impacts and may create human health hazards. The aim of this research is to find out the factors affecting the quantity of remotely-sensed NTLs in Finland at 2015. We also aim to unveil how much NTLs have changed in Finland from 1993 to 2012 and what is the share of NTLs for different land use types in Finland in 2015. Answers to these questions are achieved with satellite radiance data and data on spatial structure, multiple linear regression (MLR), and change-detection methods. National and regional MLR models were produced to explain NTL and to compare the suitability of this modelling approach in different regions. Radiance is explained by population density, industrial building density, and lit roads density. Surprisingly, the brightest areas in Finland seem to be in Närpiö, a rural area with low population density but where greenhouse farming is common. Based on change-detection, new light sources have emerged because of the expansion of mining and tourism industries.  
  Address  
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  Publisher Place of Publication Editor  
  Language Finnish Summary Language Original Title  
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  Notes Approved no  
  Call Number IDA @ intern @ Serial 2354  
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Author Sun, Shaojie; Lu, Yingcheng; Liu, Yongxue; Wang, Mengqiu; Hu, Chuanmin url  doi
openurl 
  Title Tracking an oil tanker collision and spilled oils in the East China Sea using multi‐sensor day and night satellite imagery Type Journal Article
  Year 2018 Publication (up) Geophysical Research Letters Abbreviated Journal  
  Volume 45 Issue 7 Pages 3212-3220  
  Keywords Remote Sensing  
  Abstract Satellite remote sensing is well known to play a critical role in monitoring marine accidents such as oil spills, yet the recent SANCHI oil tanker collision event in January 2018 in the East China Sea indicates that traditional techniques using synthetic aperture radar (SAR) or daytime optical imagery could not provide timely and adequate coverage. In this study, we show the unprecedented value of VIIRS Nightfire product and Day/Night Band (DNB) data in tracking the oil tanker's drifting pathway and locations when all other means are not as effective for the same purpose. Such pathway and locations can also be reproduced with a numerical model, with RMS error of < 15 km. While high‐resolution optical imagery after 4 days of the tanker's sinking reveals much larger oil spill area (> 350 km2) than previous reports, the impact of the spilled condensate oil on the marine environment requires further research.  
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  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1838  
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Author Koen, E.L.; Minnaar, C.; Roever, C.L.; Boyles, J.G. url  doi
openurl 
  Title Emerging threat of the 21(st) century lightscape to global biodiversity Type Journal Article
  Year 2018 Publication (up) Global Change Biology Abbreviated Journal Glob Chang Biol  
  Volume 24 Issue 6 Pages 2315-2324  
  Keywords Animals; Ecology; Remote Sensing  
  Abstract Over the last century the temporal and spatial distribution of light on Earth has been drastically altered by human activity. Despite mounting evidence of detrimental effects of light pollution on organisms and their trophic interactions, the extent to which light pollution threatens biodiversity on a global scale remains unclear. We assessed the spatial extent and magnitude of light encroachment by measuring change in the extent of light using satellite imagery from 1992 to 2012 relative to species richness for terrestrial and freshwater mammals, birds, reptiles, and amphibians. The encroachment of light into previously dark areas was consistently high, often doubling, in areas of high species richness for all four groups. This pattern persisted for nocturnal groups (e.g., bats, owls, and geckos) and species considered vulnerable to extinction. Areas with high species richness and large increases in light extent were clustered within newly industrialized regions where expansion of light is likely to continue unabated unless we act to conserve remaining darkness. Implementing change at a global scale requires global public, and therefore scientific, support. Here, we offer substantial evidence that light extent is increasing where biodiversity is high, representing an emerging threat to global biodiversity requiring immediate attention. This article is protected by copyright. All rights reserved.  
  Address Center for Ecology and Department of Zoology, Southern Illinois University, Carbondale, Illinois, 62901, USA  
  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 1354-1013 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:29575356 Approved no  
  Call Number GFZ @ kyba @ Serial 1833  
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