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Özyürek, C., & Aydin, G. (2015). Students’ Opinions on the Light Pollution Application. IEJEE, 8(1), 55–68.
Abstract: The purpose of this study is to determine the impact of computer-animated concept cartoons and outdoor science activities on creating awareness among seventh graders about light pollution. It also aims to identify the views of the students on the activities that were carried out. This study used one group pre-test/post-test experimental design model with 30 seventh graders. The data in the study were collected via open-ended questions on light pollution and semi-structured interview questions. The open-ended questions on light pollution were administered as a pre-test and a post-test. After the post-test was administered, semi-structured interviews were conducted with seven students. The data collected from the open-ended questions and semi-structured interviews were qualitatively analysed and quotes from the students’ statements were included. Looking at the answers of the students to questions on light pollution, it was understood that the activities that were carried out were effective. Furthermore, all of the students that were interviewed made positive statements about the activities that were carried out.
Keywords: Society; awareness; perception; education; child development; light pollution
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Bullough, J. D., Donnell, E. T., & Rea, M. S. (2013). To illuminate or not to illuminate: roadway lighting as it affects traffic safety at intersections. Accid Anal Prev, 53, 65–77.
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.
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
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Cao, D., & Barrionuevo, P. A. (2015). The importance of intrinsically photosensitive retinal ganglion cells and implications for lighting design. J Sol State Light, 2(1), 10.
Abstract: We reviewed the role of melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs) in light-dependent functions, including circadian rhythm that is important for health and visual perception. We then discussed the implications for lighting design.
Keywords: Human Health; lighting; Melanopsin; ipRGC; Photoreceptors; Circadian; Visual perception; Color Contrast; Sensitivity; LED; Lighting Design
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Czeisler, C. A., Shanahan, T. L., Klerman, E. B., Martens, H., Brotman, D. J., Emens, J. S., et al. (1995). Suppression of melatonin secretion in some blind patients by exposure to bright light. N Engl J Med, 332(1), 6–11.
Abstract: BACKGROUND: Complete blindness generally results in the loss of synchronization of circadian rhythms to the 24-hour day and in recurrent insomnia. However, some blind patients maintain circadian entrainment. We undertook this study to determine whether some blind patients' eyes convey sufficient photic information to entrain the hypothalamic circadian pacemaker and suppress melatonin secretion, despite an apparently complete loss of visual function. METHODS: We evaluated the input of light to the circadian pacemaker by testing the ability of bright light to decrease plasma melatonin concentrations in 11 blind patients with no conscious perception of light and in 6 normal subjects. We also evaluated circadian entrainment over time in the blind patients. RESULTS: Plasma melatonin concentrations decreased during exposure to bright light in three sightless patients by an average (+/- SD) of 69 +/- 21 percent and in the normal subjects by an average of 66 +/- 15 percent. When two of these blind patients were tested with their eyes covered during exposure to light, plasma melatonin did not decrease. The three blind patients reported no difficulty sleeping and maintained apparent circadian entrainment to the 24-hour day. Plasma melatonin concentrations did not decrease during exposure to bright light in seven of the remaining blind patients; in the eighth, plasma melatonin was undetectable. These eight patients reported a history of insomnia, and in four the circadian temperature rhythm was not entrained to the 24-hour day. CONCLUSIONS: The visual subsystem that mediates light-induced suppression of melatonin secretion remains functionally intact in some sightless patients. The absence of photic input to the circadian system thus constitutes a distinct form of blindness, associated with periodic insomnia, that afflicts most but not all patients with no conscious perception of light.
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DeVoe, R. D. (1972). Dual Sensitivities of Cells in Wolf Spider Eyes at Ultraviolet and Visible Wavelengths of Light. JGP, 59(3), 247–269.
Abstract: Intracellular recordings have been made from visual cells in principal and secondary eyes of in vitro wolf spider preparations. The responses of all cells to all wavelengths of light were graded depolarizations; no hyperpolarizations or nerve discharges were seen. Cells in a secondary eye, the anterior lateral eye, had a maximum sensitivity in the visible at 510 nm and a secondary maximum, or shoulder, of sensitivity in the near ultraviolet at 380 nm. Cells in principal eyes, the anterior median eyes, all responded maximally both in the visible at 510 nm and in the ultraviolet at 360-370 nm or less. However, there was no typical ratio of ultraviolet to visible sensitivities; the differences in log sensitivities (log UV/VIS) varied from 3.3 to -0.5. Each principal eye had a population of cells with different ratios. These populations varied with the time of the year, possibly due to changes in light upon the animals. Chromatic adaptations of cells in anterior median (but not anterior lateral) eyes resulted in small, selective changes in spectral sensitivities, and there was some facilitation of responses from cells repeatedly stimulated. It is concluded that cells of secondary eyes contain only a visual pigment absorbing maximally in the visible, while cells of principal eyes probably contain variable amounts of both this pigment and one absorbing in the ultraviolet as well.
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