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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 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  
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  ISSN (up) 0016-6480 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:28526480 Approved no  
  Call Number IDA @ john @ Serial 2248  
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Author Syposz, M.; Gonçalves, F.; Carty, M.; Hoppitt, W.; Manco, F. url  doi
openurl 
  Title Factors influencing Manx Shearwater grounding on the west coast of Scotland Type Journal Article
  Year 2018 Publication Ibis Abbreviated Journal Ibis  
  Volume 160 Issue 4 Pages 846-854  
  Keywords Animals  
  Abstract Grounding of thousands of newly fledged petrels and shearwaters (family Procellariidae) in built‐up areas due to artificial light is a global problem. Due to their anatomy these grounded birds find it difficult to take off from built‐up areas and many fall victim to predation, cars, dehydration or starvation. This research investigated a combination of several factors that may influence the number of Manx Shearwater Puffinus puffinus groundings in a coastal village of Scotland located close to a nesting site for this species. A model was developed that used meteorological variables and moon cycle to predict the daily quantity of birds that were recovered on the ground. The model, explaining 46.32% of the variance of the data, revealed how new moon and strong onshore winds influence grounding. To a lesser extent, visibility conditions can also have an effect on grounding probabilities. The analysis presented in this study can improve rescue campaigns of not only Manx Shearwaters but also other species attracted to the light pollution by predicting conditions leading to an increase in the number of groundings. It could also inform local authorities when artificial light intensity needs to be reduced.  
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  ISSN (up) 0019-1019 ISBN Medium  
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  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2778  
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Author Bennie, J.; Davies, T.W.; Cruse, D.; Inger, R.; Gaston, K.J.; Lewis, O. url  doi
openurl 
  Title Artificial light at night causes top-down and bottom-up trophic effects on invertebrate populations Type Journal Article
  Year 2018 Publication Journal of Applied Ecology Abbreviated Journal J Appl Ecol  
  Volume 55 Issue 6 Pages 2698-2706  
  Keywords Ecology; Animals; Plants  
  Abstract Globally, many ecosystems are exposed to artificial light at night. Nighttime lighting has direct biological impacts on species at all trophic levels. However, the effects of artificial light on biotic interactions remain, for the most part, to be determined.

We exposed experimental mesocosms containing combinations of grassland plants and invertebrate herbivores and predators to illumination at night over a 3‐year period to simulate conditions under different common forms of street lighting.

We demonstrate both top‐down (predation‐controlled) and bottom‐up (resource‐controlled) impacts of artificial light at night in grassland communities. The impacts on invertebrate herbivore abundance were wavelength‐dependent and mediated via other trophic levels.

White LED lighting decreased the abundance of a generalist herbivore mollusc by 55% in the presence of a visual predator, but not in its absence, while monochromatic amber light (with a peak wavelength similar to low‐pressure sodium lighting) decreased abundance of a specialist herbivore aphid (by 17%) by reducing the cover and flower abundance of its main food plant in the system. Artificial white light also significantly increased the food plant's foliar carbon to nitrogen ratio.

We conclude that exposure to artificial light at night can trigger ecological effects spanning trophic levels, and that the nature of such impacts depends on the wavelengths emitted by the lighting technology employed.

Policy implications. Our results confirm that artificial light at night, at illuminance levels similar to roadside vegetation, can have population effects mediated by both top‐down and bottom‐up effects on ecosystems. Given the increasing ubiquity of light pollution at night, these impacts may be widespread in the environment. These results underline the importance of minimizing ecosystem disruption by reducing light pollution in natural and seminatural ecosystems.
 
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  ISSN (up) 0021-8901 ISBN Medium  
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  Notes Approved no  
  Call Number NC @ ehyde3 @ Serial 2086  
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Author Wakefield, A.; Broyles, M.; Stone, E.L.; Harris, S.; Jones, G.; Minderman, J. url  doi
openurl 
  Title Quantifying the attractiveness of broad-spectrum street lights to aerial nocturnal insects Type Journal Article
  Year 2018 Publication Journal of Applied Ecology Abbreviated Journal J Appl Ecol  
  Volume 55 Issue 2 Pages 714-722  
  Keywords Animals  
  Abstract Sodium street lights, dominated by long wavelengths of light, are being replaced by broad‐spectrum, white lights globally, in particular light‐emitting diodes (LEDs). These white lights typically require less energy to operate and are therefore considered “eco‐friendly”. However, little attention has been paid to the impacts white lights may have upon local wildlife populations.

We compared insect attraction to orange (high‐pressure sodium, HPS) and white (metal halide, MH and LED) street lights experimentally using portable street lights and custom‐made flight intercept traps.

Significantly more (greater than five times as many) insects were attracted to white MH street lights than white (4,250 K) LED and HPS lights. There was no statistical difference in the numbers of insects attracted to LED and HPS lights for most taxa caught. However, rarefaction shows a greater diversity of insects caught at LED than HPS lights.

Policy implications. With the current, large‐scale conversion to white light‐emitting diode (LED) lighting, our results give insight into how changes to street light technology may affect wildlife populations and communities. We recommend avoiding metal halide light installations as they attract many more insects than competing technologies. We highlight the need to tailor LED lighting to prevent disturbances across multiple insect taxa.
 
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  ISSN (up) 0021-8901 ISBN Medium  
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  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2224  
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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 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  
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  Language English Summary Language Original Title  
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  ISSN (up) 0021-9738 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:29953415; PMCID:PMC6118629 Approved no  
  Call Number GFZ @ kyba @ Serial 2194  
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