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Author (up) Arendt, J. url  doi
openurl 
  Title Biological rhythms during residence in polar regions Type Journal Article
  Year 2012 Publication Chronobiology International Abbreviated Journal Chronobiol Int  
  Volume 29 Issue 4 Pages 379-394  
  Keywords *Acclimatization; Activities of Daily Living; Affect; Antarctic Regions; Arctic Regions; *Biological Clocks; *Circadian Rhythm; *Cold Climate; *Cold Temperature; Energy Metabolism; Feeding Behavior; Humans; Melatonin/metabolism; Personnel Staffing and Scheduling; *Photoperiod; Seasonal Affective Disorder/physiopathology/prevention & control/psychology; *Seasons; Sleep; Sleep Disorders, Circadian Rhythm/etiology/physiopathology/*prevention & control/psychology; Time Factors; Workload; Workplace  
  Abstract At Arctic and Antarctic latitudes, personnel are deprived of natural sunlight in winter and have continuous daylight in summer: light of sufficient intensity and suitable spectral composition is the main factor that maintains the 24-h period of human circadian rhythms. Thus, the status of the circadian system is of interest. Moreover, the relatively controlled artificial light conditions in winter are conducive to experimentation with different types of light treatment. The hormone melatonin and/or its metabolite 6-sulfatoxymelatonin (aMT6s) provide probably the best index of circadian (and seasonal) timing. A frequent observation has been a delay of the circadian system in winter. A skeleton photoperiod (2 x 1-h, bright white light, morning and evening) can restore summer timing. A single 1-h pulse of light in the morning may be sufficient. A few people desynchronize from the 24-h day (free-run) and show their intrinsic circadian period, usually >24 h. With regard to general health in polar regions, intermittent reports describe abnormalities in various physiological processes from the point of view of daily and seasonal rhythms, but positive health outcomes are also published. True winter depression (SAD) appears to be rare, although subsyndromal SAD is reported. Probably of most concern are the numerous reports of sleep problems. These have prompted investigations of the underlying mechanisms and treatment interventions. A delay of the circadian system with “normal” working hours implies sleep is attempted at a suboptimal phase. Decrements in sleep efficiency, latency, duration, and quality are also seen in winter. Increasing the intensity of ambient light exposure throughout the day advanced circadian phase and was associated with benefits for sleep: blue-enriched light was slightly more effective than standard white light. Effects on performance remain to be fully investigated. At 75 degrees S, base personnel adapt the circadian system to night work within a week, in contrast to temperate zones where complete adaptation rarely occurs. A similar situation occurs on high-latitude North Sea oil installations, especially when working 18:00-06:00 h. Lack of conflicting light exposure (and “social obligations”) is the probable explanation. Many have problems returning to day work, showing circadian desynchrony. Timed light treatment again has helped to restore normal phase/sleep in a small number of people. Postprandial response to meals is compromised during periods of desynchrony with evidence of insulin resistance and elevated triglycerides, risk factors for heart disease. Only small numbers of subjects have been studied intensively in polar regions; however, these observations suggest that suboptimal light conditions are deleterious to health. They apply equally to people living in temperate zones with insufficient light exposure.  
  Address Centre for Chronobiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey, UK. arendtjo@gmail.com  
  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 0742-0528 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:22497433; PMCID:PMC3793275 Approved no  
  Call Number IDA @ john @ Serial 143  
Permanent link to this record
 

 
Author (up) Burkett, D.A.; Butler, J.F. url  openurl
  Title Laboratory Evaluation of Colored Light as an Attractant for Female Aedes Aegypti, Aedes Albopictus, Anopheles Quadrimaculatus, and Culex Nigripalpus Type Journal Article
  Year 2005 Publication The Florida Entomologist Abbreviated Journal Florida Entomologist  
  Volume 88 Issue 4 Pages 383-389  
  Keywords Animals; insects; mosquito; visualometer; Aedes albopictus; Aedes aegypti; Anopheles quadrimaculatus; Culex nigripalpus; Feeding Behavior  
  Abstract Mosquito feeding activity was monitored in an electronic apparatus (visualometer), having ten ports, illuminated from below with narrow bandwidths of light (700, 650, 600, 550, 500, 450, 400, or 350 nm). Responses of adult female Aedes albopictus Skuse, Ae. aegypti (L.), Anopheles quadrimaculatus, Say and Culex nigripalpus Theobald to feeding stations (blood containers) over each light port. No-light and broad spectrum white light were used as controls. Color preferences were based on electronic detection of feeding times. Aedes aegypti showed no significant feeding preferences over any of the colors. Conversely, Ae. albopictus, An. quadrimaculatus, and Cx. nigripalpus showed preferences for several of the wavelengths of light. In decreasing order, Aedes albopictus fed significantly longer at 600 nm, 500 nm, white, 450 nm, 400 nm, and black. For An. quadrimaculatus, significantly longer feeding durations were found over the black or white controls and all other individual wavelengths had significantly longer feeding durations than 350 nm. Finally, in decreasing order, significantly greater feeding times were recorded for Cx. nigripalpus over 500 nm, 600 nm, 450 nm, white, 650 nm, and 550 nm compared to the other wavelengths tested.  
  Address Range Operations Environmental ACC/DOPP HQACC-Ranges, Airfields & Airspace Ops; douglas.burkett(at)langley.af.mil  
  Corporate Author Thesis  
  Publisher Florida Entomological Society Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1938-5102 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1368  
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Author (up) Dacke, M.; Nilsson, D.-E.; Scholtz, C.H.; Byrne, M.; Warrant, E.J. url  doi
openurl 
  Title Animal behaviour: insect orientation to polarized moonlight Type Journal Article
  Year 2003 Publication Nature Abbreviated Journal Nature  
  Volume 424 Issue 6944 Pages 33  
  Keywords Adaptation, Physiological/physiology; Animals; Beetles/*physiology; Feces; Feeding Behavior/physiology; *Light; Locomotion/*physiology; *Moon; Orientation/*physiology; Scarabaeus zambesianus  
  Abstract Moonlight, like sunlight, scatters when it strikes tiny particles in the atmosphere, giving rise to celestial polarization patterns. Here we show that an African dung beetle, Scarabaeus zambesianus, uses the polarization of a moonlit sky to orientate itself so that it can move along a straight line. Many creatures use the Sun's light-polarization pattern to orientate themselves, but S. zambesianus is the first animal known to use the million-times dimmer polarization of moonlight for this purpose.  
  Address Department of Cell and Organism Biology, University of Lund, 223 62 Lund, Sweden. marie.dacke@cob.lu.se  
  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 0028-0836 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12840748 Approved no  
  Call Number IDA @ john @ Serial 242  
Permanent link to this record
 

 
Author (up) Fonken, L.K.; Aubrecht, T.G.; Melendez-Fernandez, O.H.; Weil, Z.M.; Nelson, R.J. url  doi
openurl 
  Title Dim light at night disrupts molecular circadian rhythms and increases body weight Type Journal Article
  Year 2013 Publication Journal of Biological Rhythms Abbreviated Journal J Biol Rhythms  
  Volume 28 Issue 4 Pages 262-271  
  Keywords Animals; Blood Glucose/metabolism; Body Weight/*physiology; CLOCK Proteins/biosynthesis/genetics; Circadian Rhythm/*physiology; Corticosterone/metabolism; Feeding Behavior/physiology; Immunohistochemistry; Light; *Lighting; Male; Mice; Motor Activity; Polymerase Chain Reaction; Suprachiasmatic Nucleus/metabolism/physiology; clock genes; feeding rhythm; light pollution; obesity  
  Abstract With the exception of high latitudes, life has evolved under bright days and dark nights. Most organisms have developed endogenously driven circadian rhythms that are synchronized to this daily light/dark cycle. In recent years, humans have shifted away from the naturally occurring solar light cycle in favor of artificial and sometimes irregular light schedules produced by electric lighting. Exposure to unnatural light cycles is increasingly associated with obesity and metabolic syndrome; however, the means by which environmental lighting alters metabolism are poorly understood. Thus, we exposed mice to dim light at night and investigated changes in the circadian system and metabolism. Here we report that exposure to ecologically relevant levels of dim (5 lux) light at night altered core circadian clock rhythms in the hypothalamus at both the gene and protein level. Circadian rhythms in clock expression persisted during light at night; however, the amplitude of Per1 and Per2 rhythms was attenuated in the hypothalamus. Circadian oscillations were also altered in peripheral tissues critical for metabolic regulation. Exposure to dimly illuminated, as compared to dark, nights decreased the rhythmic expression in all but one of the core circadian clock genes assessed in the liver. Additionally, mice exposed to dim light at night attenuated Rev-Erb expression in the liver and adipose tissue. Changes in the circadian clock were associated with temporal alterations in feeding behavior and increased weight gain. These results are significant because they provide evidence that mild changes in environmental lighting can alter circadian and metabolic function. Detailed analysis of temporal changes induced by nighttime light exposure may provide insight into the onset and progression of obesity and metabolic syndrome, as well as other disorders involving sleep and circadian rhythm disruption.  
  Address Department of Neuroscience and Institute for Behavioral Medicine Research, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA. fonken.1@osu.edu  
  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 0748-7304 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23929553; PMCID:PMC4033305 Approved no  
  Call Number IDA @ john @ Serial 28  
Permanent link to this record
 

 
Author (up) Fonken, L.K.; Lieberman, R.A.; Weil, Z.M.; Nelson, R.J. url  doi
openurl 
  Title Dim light at night exaggerates weight gain and inflammation associated with a high-fat diet in male mice Type Journal Article
  Year 2013 Publication Endocrinology Abbreviated Journal Endocrinology  
  Volume 154 Issue 10 Pages 3817-3825  
  Keywords Adipose Tissue, White/*immunology/metabolism/pathology; Animals; Antigens, CD11b/biosynthesis/genetics/metabolism; Appetite Regulation/*radiation effects; Arcuate Nucleus/*immunology/metabolism/pathology; Behavior, Animal/radiation effects; Circadian Rhythm; Cytokines/biosynthesis/genetics/metabolism; Diet, High-Fat/*adverse effects; Feeding Behavior/radiation effects; Gene Expression Regulation; Glucose Intolerance/etiology/immunology/metabolism/pathology; I-kappa B Kinase/biosynthesis/genetics/metabolism; Insulin Resistance; Lighting/*adverse effects; Male; Mice; Microglia/immunology/metabolism/pathology; Nerve Tissue Proteins/biosynthesis/genetics/metabolism; Obesity/*etiology/immunology/metabolism/pathology; Random Allocation; *Weight Gain  
  Abstract Elevated nighttime light exposure is associated with symptoms of metabolic syndrome. In industrialized societies, high-fat diet (HFD) and exposure to light at night (LAN) often cooccur and may contribute to the increasing obesity epidemic. Thus, we hypothesized that dim LAN (dLAN) would provoke additional and sustained body mass gain in mice on a HFD. Male mice were housed in either a standard light/dark cycle or dLAN and fed either chow or HFD. Exposure to dLAN and HFD increase weight gain, reduce glucose tolerance, and alter insulin secretion as compared with light/dark cycle and chow, respectively. The effects of dLAN and HFD appear additive, because mice exposed to dLAN that were fed HFD display the greatest increases in body mass. Exposure to both dLAN and HFD also change the timing of food intake and increase TNFalpha and MAC1 gene expression in white adipose tissue after 4 experimental weeks. Changes in MAC1 gene expression occur more rapidly due to HFD as compared with dLAN; after 5 days of experimental conditions, mice fed HFD already increase MAC1 gene expression in white adipose tissue. HFD also elevates microglia activation in the arcuate nucleus of the hypothalamus and hypothalamic TNFalpha, IL-6, and Ikbkb gene expression. Microglia activation is increased by dLAN, but only among chow-fed mice and dLAN does not affect inflammatory gene expression. These results suggest that dLAN exaggerates weight gain and peripheral inflammation associated with HFD.  
  Address Department of Neuroscience, Wexner Medical Center, The Ohio State University, 636 Biomedical Research Tower, 460 West 12th Avenue, Columbus, Ohio 43210. fonken.1@osu.edu  
  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 0013-7227 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23861373 Approved no  
  Call Number IDA @ john @ Serial 93  
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