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Author Boivin, D.B.; Boudreau, P.; Tremblay, G.M. url  doi
openurl 
  Title Phototherapy and orange-tinted goggles for night-shift adaptation of police officers on patrol Type Journal Article
  Year 2012 Publication Chronobiology International Abbreviated Journal Chronobiol Int  
  Volume 29 Issue 5 Pages 629-640  
  Keywords Human Health; Adaptation, Physiological/*physiology; Adult; Attention/physiology; Circadian Rhythm/physiology; Color; Darkness; *Eye Protective Devices/adverse effects; Female; Humans; Light; Male; Melatonin/analogs & derivatives/metabolism/urine; Phototherapy/*adverse effects; *Police; Psychomotor Performance/*physiology; Saliva/chemistry; Sleep/physiology; Work Schedule Tolerance/*physiology  
  Abstract The aim of the present combined field and laboratory study was to assess circadian entrainment in two groups of police officers working seven consecutive 8/8.5-h night shifts as part of a rotating schedule. Eight full-time police officers on patrol (mean age +/- SD: 29.8 +/- 6.5 yrs) were provided an intervention consisting of intermittent exposure to wide-spectrum bright light at night, orange-tinted goggles at sunrise, and maintenance of a regular sleep/darkness episode in the day. Orange-tinted goggles have been shown to block the melatonin-suppressing effect of light significantly more than neutral gray density goggles. Nine control group police officers (mean age +/- SD: 30.3 +/- 4.1 yrs) working the same schedule were enrolled. Police officers were studied before, after (in the laboratory), and during (ambulatory) a series of seven consecutive nights. Urine samples were collected at wake time and bedtime throughout the week of night work and during laboratory visits (1 x /3 h) preceding and following the work week to measure urinary 6-sulfatoxymelatonin (UaMT6s) excretion rate. Subjective alertness was assessed at the start, middle, and end of night shifts. A 10-min psychomotor vigilance task was performed at the start and end of each shift. Both laboratory visits consisted of two 8-h sleep episodes based on the prior schedule. Saliva samples were collected 2 x /h during waking episodes to assay their melatonin content. Subjective alertness (3 x /h) and performance (1 x /2 h) were assessed during wake periods in the laboratory. A mixed linear model was used to analyze the progression of UaMt6s excreted during daytime sleep episodes at home, as well as psychomotor performance and subjective alertness during night shifts. Two-way analysis of variance (ANOVA) (factors: laboratory visit and group) were used to compare peak salivary melatonin and UaMT6s excretion rate in the laboratory. In both groups of police officers, the excretion rate of UaMT6s at home was higher during daytime sleep episodes at the end compared to the start of the work week (p < .001). This rate increased significantly more in the intervention than control group (p = .032). A significant phase delay of salivary melatonin was observed in both groups at the end of study (p = .009), although no significant between-group difference was reached. Reaction speed dropped, and subjective alertness decreased throughout the night shift in both groups (p < .001). Reaction speed decreased throughout the work week in the control group (p </= .021), whereas no difference was observed in the intervention group. Median reaction time was increased as of the 5th and 6th nights compared to the 2nd night in controls (p </= .003), whereas it remained stable in the intervention group. These observations indicate better physiological adaptation in the intervention group compared to the controls.  
  Address Centre for Study and Treatment of Circadian Rhythms , Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montreal, Quebec, Canada. diane.boivin@douglas.mcgill.ca  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0742-0528 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:22621360 Approved no  
  Call Number LoNNe @ christopher.kyba @ Serial 509  
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Author Bullough, J.D.; Donnell, E.T.; Rea, M.S. url  doi
openurl 
  Title To illuminate or not to illuminate: roadway lighting as it affects traffic safety at intersections Type Journal Article
  Year 2013 Publication Accident; Analysis and Prevention Abbreviated Journal Accid Anal Prev  
  Volume 53 Issue Pages 65-77  
  Keywords Lighting; Accident Prevention/*methods; Accidents, Traffic/*prevention & control/psychology/statistics & numerical data; Cross-Sectional Studies; *Environment Design; Humans; *Lighting; Minnesota; Models, Statistical; Photoperiod; Psychomotor Performance; Regression Analysis; Safety/statistics & numerical data; Visual Perception  
  Abstract A two-pronged effort to quantify the impact of lighting on traffic safety is presented. In the statistical approach, the effects of lighting on crash frequency for different intersection types in Minnesota were assessed using count regression models. The models included many geometric and traffic control variables to estimate the association between lighting and nighttime and daytime crashes and the resulting night-to-day crash ratios. Overall, the presence of roadway intersection lighting was found to be associated with an approximately 12% lower night-to-day crash ratio than unlighted intersections. In the parallel analytical approach, visual performance analyses based on roadway intersection lighting practices in Minnesota were made for the same intersection types investigated in the statistical approach. The results of both approaches were convergent, suggesting that visual performance improvements from roadway lighting could serve as input for predicting improvements in crash frequency. A provisional transfer function allows transportation engineers to evaluate alternative lighting systems in the design phase so selections based on expected benefits and costs can be made.  
  Address Lighting Research Center, Rensselaer Polytechnic Institute, 21 Union Street, Troy, NY 12180, USA  
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  Language English Summary Language Original Title  
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  ISSN 0001-4575 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23377085 Approved no  
  Call Number LoNNe @ kagoburian @ Serial 627  
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Author Cajochen, C.; Frey, S.; Anders, D.; Spati, J.; Bues, M.; Pross, A.; Mager, R.; Wirz-Justice, A.; Stefani, O. url  doi
openurl 
  Title Evening exposure to a light-emitting diodes (LED)-backlit computer screen affects circadian physiology and cognitive performance Type Journal Article
  Year 2011 Publication Journal of Applied Physiology (Bethesda, Md. : 1985) Abbreviated Journal J Appl Physiol (1985)  
  Volume 110 Issue 5 Pages 1432-1438  
  Keywords Adult; Circadian Rhythm/*physiology/radiation effects; Cognition/*physiology/radiation effects; *Computer Terminals; Humans; Light; Lighting/*methods; Male; Photic Stimulation/*methods; Radiation Dosage; Semiconductors; *Task Performance and Analysis; Young Adult; blue light; sleep; circadian disruption  
  Abstract Many people spend an increasing amount of time in front of computer screens equipped with light-emitting diodes (LED) with a short wavelength (blue range). Thus we investigated the repercussions on melatonin (a marker of the circadian clock), alertness, and cognitive performance levels in 13 young male volunteers under controlled laboratory conditions in a balanced crossover design. A 5-h evening exposure to a white LED-backlit screen with more than twice as much 464 nm light emission {irradiance of 0,241 Watt/(steradian x m(2)) [W/(sr x m(2))], 2.1 x 10(13) photons/(cm(2) x s), in the wavelength range of 454 and 474 nm} than a white non-LED-backlit screen [irradiance of 0,099 W/(sr x m(2)), 0.7 x 10(13) photons/(cm(2) x s), in the wavelength range of 454 and 474 nm] elicited a significant suppression of the evening rise in endogenous melatonin and subjective as well as objective sleepiness, as indexed by a reduced incidence of slow eye movements and EEG low-frequency activity (1-7 Hz) in frontal brain regions. Concomitantly, sustained attention, as determined by the GO/NOGO task; working memory/attention, as assessed by “explicit timing”; and declarative memory performance in a word-learning paradigm were significantly enhanced in the LED-backlit screen compared with the non-LED condition. Screen quality and visual comfort were rated the same in both screen conditions, whereas the non-LED screen tended to be considered brighter. Our data indicate that the spectral profile of light emitted by computer screens impacts on circadian physiology, alertness, and cognitive performance levels. The challenge will be to design a computer screen with a spectral profile that can be individually programmed to add timed, essential light information to the circadian system in humans.  
  Address Centre for Chronobiology, Psychiatric Hospitals of the University of Basel, Basel, Switzerland. christian.cajochen@upkbs.ch  
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  ISSN 0161-7567 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:21415172 Approved no  
  Call Number IDA @ john @ Serial 293  
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Author Chang, A.-M.; Scheer, F.A.J.L.; Czeisler, C.A.; Aeschbach, D. url  doi
openurl 
  Title Direct effects of light on alertness, vigilance, and the waking electroencephalogram in humans depend on prior light history Type Journal Article
  Year 2013 Publication Sleep Abbreviated Journal Sleep  
  Volume 36 Issue 8 Pages 1239-1246  
  Keywords Arousal/*radiation effects; Attention/radiation effects; Cross-Over Studies; *Electroencephalography; Female; Humans; *Light; Male; Melatonin/blood/physiology; Psychomotor Performance/radiation effects; Reaction Time; Wakefulness/*radiation effects; Young Adult; Light history; alertness and performance; light exposure  
  Abstract STUDY OBJECTIVES: Light can induce an acute alerting response in humans; however, it is unknown whether the magnitude of this response is simply a function of the absolute illuminance of the light itself, or whether it depends on illuminance history preceding the stimulus. Here, we compared the effects of illuminance history on the alerting response to a subsequent light stimulus. DESIGN: A randomized, crossover design was used to compare the effect of two illuminance histories (1 lux vs. 90 lux) on the alerting response to a 6.5-h 90-lux light stimulus during the biological night. SETTING: Intensive Physiologic Monitoring Unit, Brigham and Women's Hospital, Boston, MA. PARTICIPANTS: Fourteen healthy young adults (6 F; 23.5 +/- 2.9 years). INTERVENTIONS: Participants were administered two 6.5-h light exposures (LE) of 90 lux during the biological night. For 3 days prior to each LE, participants were exposed to either 1 lux or 90 lux during the wake episode. MEASUREMENTS AND RESULTS: The alerting response to light was assessed using subjective sleepiness ratings, lapses of attention, and reaction times as measured with an auditory psychomotor vigilance task, as well as power density in the delta/theta range of the waking EEG. The alerting response to light was greater and lasted longer when the LE followed exposure to 1 lux compared to 90 lux light. CONCLUSION: The magnitude and duration of the alerting effect of light at night depends on the illuminance history and appears to be subject to sensitization and adaptation.  
  Address Division of Sleep Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA. amchang@rics.bwh.harvard.edu  
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  Series Volume Series Issue Edition  
  ISSN 0161-8105 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23904684; PMCID:PMC3700721 Approved no  
  Call Number IDA @ john @ Serial 145  
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Author Dukic, T.; Ahlstrom, C.; Patten, C.; Kettwich, C.; Kircher, K. url  doi
openurl 
  Title Effects of electronic billboards on driver distraction Type Journal Article
  Year 2013 Publication Traffic Injury Prevention Abbreviated Journal Traffic Inj Prev  
  Volume 14 Issue 5 Pages 469-476  
  Keywords Adult; Advertising as Topic/*methods; *Attention; Automobile Driving/*psychology; Eye Movements; Humans; Middle Aged; Psychomotor Performance; Sweden; Time Factors  
  Abstract OBJECTIVE: There is an increase in electronic advertising billboards along major roads, which may cause driver distraction due to the highly conspicuous design of the electronic billboards. Yet limited research on the impact of electronic billboards on driving performance and driver behavior is available. The Swedish Transport Administration recently approved the installation of 12 electronic billboards for a trial period along a 3-lane motorway with heavy traffic running through central Stockholm, Sweden. The aim of this study was to evaluate the effect of these electronic billboards on visual behavior and driving performance. METHOD: A total of 41 drivers were recruited to drive an instrumented vehicle passing 4 of the electronic billboards during day and night conditions. A driver was considered visually distracted when looking at a billboard continuously for more than 2 s or if the driver looked away from the road for a high percentage of time. Dependent variables were eye-tracking measures and driving performance measures. RESULTS: The visual behavior data showed that drivers had a significantly longer dwell time, a greater number of fixations, and longer maximum fixation duration when driving past an electronic billboard compared to other signs on the same road stretches. No differences were found for the factors day/night, and no effect was found for the driving behavior data. CONCLUSION: Electronic billboards have an effect on gaze behavior by attracting more and longer glances than regular traffic signs. Whether the electronic billboards attract too much attention and constitute a traffic safety hazard cannot be answered conclusively based on the present data.  
  Address Swedish National Road and Transport Research Institute, Linkoping, Sweden. tania.dukic@vti.se  
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  Series Volume Series Issue Edition  
  ISSN 1538-9588 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23682577 Approved no  
  Call Number IDA @ john @ Serial 247  
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