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Author Orbach, D.N.; Fenton, B. url  doi
openurl 
  Title Vision impairs the abilities of bats to avoid colliding with stationary obstacles Type Journal Article
  Year 2010 Publication PloS one Abbreviated Journal PLoS One  
  Volume 5 Issue 11 Pages (up) e13912  
  Keywords Analysis of Variance; Animals; Chiroptera/*physiology; Cyclonic Storms; Echolocation/*physiology; Female; Flight, Animal/*physiology; Light; Male; Space Perception/physiology/radiation effects; Vision, Ocular/*physiology/radiation effects; Vocalization, Animal/physiology  
  Abstract BACKGROUND: Free-flying insectivorous bats occasionally collide with stationary objects they should easily detect by echolocation and avoid. Collisions often occur with lighted objects, suggesting ambient light may deleteriously affect obstacle avoidance capabilities. We tested the hypothesis that free-flying bats may orient by vision when they collide with some obstacles. We additionally tested whether acoustic distractions, such as “distress calls” of other bats, contributed to probabilities of collision. METHODOLOGY/PRINCIPAL FINDINGS: To investigate the role of visual cues in the collisions of free-flying little brown bats (Myotis lucifugus) with stationary objects, we set up obstacles in an area of high bat traffic during swarming. We used combinations of light intensities and visually dissimilar obstacles to verify that bats orient by vision. In early August, bats collided more often in the light than the dark, and probabilities of collision varied with the visibility of obstacles. However, the probabilities of collisions altered in mid to late August, coincident with the start of behavioural, hormonal, and physiological changes occurring during swarming and mating. Distress calls did not distract bats and increase the incidence of collisions. CONCLUSIONS/SIGNIFICANCE: Our findings indicate that visual cues are more important for free-flying bats than previously recognized, suggesting integration of multi-sensory modalities during orientation. Furthermore, our study highlights differences between responses of captive and wild bats, indicating a need for more field experiments.  
  Address Department of Biology, University of Western Ontario, London, Ontario, Canada. dnorbach@gmail.com  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
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  ISSN 1932-6203 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:21085481; PMCID:PMC2976695 Approved no  
  Call Number IDA @ john @ Serial 96  
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Author Yasuniwa, Y.; Izumi, H.; Wang, K.-Y.; Shimajiri, S.; Sasaguri, Y.; Kawai, K.; Kasai, H.; Shimada, T.; Miyake, K.; Kashiwagi, E.; Hirano, G.; Kidani, A.; Akiyama, M.; Han, B.; Wu, Y.; Ieiri, I.; Higuchi, S.; Kohno, K. url  doi
openurl 
  Title Circadian disruption accelerates tumor growth and angio/stromagenesis through a Wnt signaling pathway Type Journal Article
  Year 2010 Publication PloS one Abbreviated Journal PLoS One  
  Volume 5 Issue 12 Pages (up) e15330  
  Keywords Animals; *Circadian Rhythm; Disease Progression; *Gene Expression Regulation, Neoplastic; HeLa Cells; Humans; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasm Transplantation; Neoplasms/*pathology; *Neovascularization, Pathologic; Nerve Tissue Proteins/metabolism; Skin/metabolism; Vascular Endothelial Growth Factor A/metabolism; Wnt Proteins/*metabolism; Oncogenesis  
  Abstract Epidemiologic studies show a high incidence of cancer in shift workers, suggesting a possible relationship between circadian rhythms and tumorigenesis. However, the precise molecular mechanism played by circadian rhythms in tumor progression is not known. To identify the possible mechanisms underlying tumor progression related to circadian rhythms, we set up nude mouse xenograft models. HeLa cells were injected in nude mice and nude mice were moved to two different cases, one case is exposed to a 24-hour light cycle (L/L), the other is a more “normal” 12-hour light/dark cycle (L/D). We found a significant increase in tumor volume in the L/L group compared with the L/D group. In addition, tumor microvessels and stroma were strongly increased in L/L mice. Although there was a hypervascularization in L/L tumors, there was no associated increase in the production of vascular endothelial cell growth factor (VEGF). DNA microarray analysis showed enhanced expression of WNT10A, and our subsequent study revealed that WNT10A stimulates the growth of both microvascular endothelial cells and fibroblasts in tumors from light-stressed mice, along with marked increases in angio/stromagenesis. Only the tumor stroma stained positive for WNT10A and WNT10A is also highly expressed in keloid dermal fibroblasts but not in normal dermal fibroblasts indicated that WNT10A may be a novel angio/stromagenic growth factor. These findings suggest that circadian disruption induces the progression of malignant tumors via a Wnt signaling pathway.  
  Address Department of Molecular Biology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan  
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  ISSN 1932-6203 ISBN Medium  
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  Notes PMID:21203463; PMCID:PMC3009728 Approved no  
  Call Number IDA @ john @ Serial 162  
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Author Chellappa, S.L.; Steiner, R.; Blattner, P.; Oelhafen, P.; Gotz, T.; Cajochen, C. url  doi
openurl 
  Title Non-visual effects of light on melatonin, alertness and cognitive performance: can blue-enriched light keep us alert? Type Journal Article
  Year 2011 Publication PloS one Abbreviated Journal PLoS One  
  Volume 6 Issue 1 Pages (up) e16429  
  Keywords Circadian Rhythm/radiation effects; Cognition/*radiation effects; Color; Cross-Over Studies; Fluorescence; Humans; *Light; Male; Melatonin/*radiation effects; Reaction Time/*radiation effects; Young Adult; blue light  
  Abstract BACKGROUND: Light exposure can cascade numerous effects on the human circadian process via the non-imaging forming system, whose spectral relevance is highest in the short-wavelength range. Here we investigated if commercially available compact fluorescent lamps with different colour temperatures can impact on alertness and cognitive performance. METHODS: Sixteen healthy young men were studied in a balanced cross-over design with light exposure of 3 different light settings (compact fluorescent lamps with light of 40 lux at 6500K and at 2500K and incandescent lamps of 40 lux at 3000K) during 2 h in the evening. RESULTS: Exposure to light at 6500K induced greater melatonin suppression, together with enhanced subjective alertness, well-being and visual comfort. With respect to cognitive performance, light at 6500K led to significantly faster reaction times in tasks associated with sustained attention (Psychomotor Vigilance and GO/NOGO Task), but not in tasks associated with executive function (Paced Visual Serial Addition Task). This cognitive improvement was strongly related with attenuated salivary melatonin levels, particularly for the light condition at 6500K. CONCLUSIONS: Our findings suggest that the sensitivity of the human alerting and cognitive response to polychromatic light at levels as low as 40 lux, is blue-shifted relative to the three-cone visual photopic system. Thus, the selection of commercially available compact fluorescent lights with different colour temperatures significantly impacts on circadian physiology and cognitive performance at home and in the workplace.  
  Address Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland  
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  ISSN 1932-6203 ISBN Medium  
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  Notes PMID:21298068; PMCID:PMC3027693 Approved no  
  Call Number IDA @ john @ Serial 286  
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Author Kyba, C.C.M.; Ruhtz, T.; Fischer, J.; Hölker, F. url  doi
openurl 
  Title Cloud coverage acts as an amplifier for ecological light pollution in urban ecosystems Type Journal Article
  Year 2011 Publication PloS one Abbreviated Journal PLoS One  
  Volume 6 Issue 3 Pages (up) e17307  
  Keywords Berlin; *Cities; *Ecosystem; Environmental Pollution/*adverse effects/analysis; *Light; Seasons; *Weather  
  Abstract The diurnal cycle of light and dark is one of the strongest environmental factors for life on Earth. Many species in both terrestrial and aquatic ecosystems use the level of ambient light to regulate their metabolism, growth, and behavior. The sky glow caused by artificial lighting from urban areas disrupts this natural cycle, and has been shown to impact the behavior of organisms, even many kilometers away from the light sources. It could be hypothesized that factors that increase the luminance of the sky amplify the degree of this “ecological light pollution”. We show that cloud coverage dramatically amplifies the sky luminance, by a factor of 10.1 for one location inside of Berlin and by a factor of 2.8 at 32 km from the city center. We also show that inside of the city overcast nights are brighter than clear rural moonlit nights, by a factor of 4.1. These results have important implications for choronobiological and chronoecological studies in urban areas, where this amplification effect has previously not been considered.  
  Address Institute for Space Sciences, Freie Universitat Berlin, Berlin, Germany. christopher.kyba@wew.fu-berlin.de  
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  ISSN 1932-6203 ISBN Medium  
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  Notes PMID:21399694; PMCID:PMC3047560 Approved no  
  Call Number IDA @ john @ Serial 20  
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Author Longcore, T.; Rich, C.; Mineau, P.; MacDonald, B.; Bert, D.G.; Sullivan, L.M.; Mutrie, E.; Gauthreaux, S.A.J.; Avery, M.L.; Crawford, R.L.; Manville, A.M. 2nd; Travis, E.R.; Drake, D. url  doi
openurl 
  Title An estimate of avian mortality at communication towers in the United States and Canada Type Journal Article
  Year 2012 Publication PloS one Abbreviated Journal PLoS One  
  Volume 7 Issue 4 Pages (up) e34025  
  Keywords Ecology; Accidents/*statistics & numerical data; Altitude; Animals; Birds/*injuries; Canada; Computer Communication Networks/*instrumentation; Conservation of Natural Resources/*statistics & numerical data; *Flight, Animal; *Mortality; Regression Analysis; United States  
  Abstract Avian mortality at communication towers in the continental United States and Canada is an issue of pressing conservation concern. Previous estimates of this mortality have been based on limited data and have not included Canada. We compiled a database of communication towers in the continental United States and Canada and estimated avian mortality by tower with a regression relating avian mortality to tower height. This equation was derived from 38 tower studies for which mortality data were available and corrected for sampling effort, search efficiency, and scavenging where appropriate. Although most studies document mortality at guyed towers with steady-burning lights, we accounted for lower mortality at towers without guy wires or steady-burning lights by adjusting estimates based on published studies. The resulting estimate of mortality at towers is 6.8 million birds per year in the United States and Canada. Bootstrapped subsampling indicated that the regression was robust to the choice of studies included and a comparison of multiple regression models showed that incorporating sampling, scavenging, and search efficiency adjustments improved model fit. Estimating total avian mortality is only a first step in developing an assessment of the biological significance of mortality at communication towers for individual species or groups of species. Nevertheless, our estimate can be used to evaluate this source of mortality, develop subsequent per-species mortality estimates, and motivate policy action.  
  Address The Urban Wildlands Group, Los Angeles, California, United States of America. longcore@urbanwildlands.org  
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  ISSN 1932-6203 ISBN Medium  
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  Notes PMID:22558082; PMCID:PMC3338802 Approved no  
  Call Number LoNNe @ christopher.kyba @ Serial 475  
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