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Hines, C. W., Fang, Y., Chan, V. K. S., Stiller, K. T., Brauner, C. J., & Richards, J. G. (2018). The effect of salinity and photoperiod on thermal tolerance of Atlantic and coho salmon reared from smolt to adult in recirculating aquaculture systems. Comp Biochem Physiol A Mol Integr Physiol, 230, 1–6.
Abstract: Land-based, closed containment salmon aquaculture involves rearing salmon from smolt to adult in recirculating aquaculture systems (RAS). Unlike in open-net pen aquaculture, rearing conditions can be specified in RAS in order to optimize growth and physiological stress tolerance. The environmental conditions that yield optimal stress tolerance in salmon are, however, unknown. To address this knowledge gap, we reared Atlantic (Salmo salar) and coho (Oncorhynchus kisutch) salmon in 7 separate RASs for 400days post-smoltification under 2 photoperiods (24:0 or 12:12, light:dark) and 4 salinities (2.5, 5, 10 or 30ppt.) and assessed the effects of these conditions on thermal tolerance. We found that over the first 120days post-smoltification, rearing coho under a 24:0 photoperiod resulted in a ~2 degrees C lower critical thermal maxima (CTmax) than in coho reared under a 12:12 photoperiod. This photoperiod effect did not persist at 200 and 400days, which was coincident with an overall decrease in CTmax in coho. Finally, Atlantic salmon had a higher CTmax (~28 degrees C) compared to coho (~26 degrees C) at 400days post-smoltification. Overall, these findings are important for the future implications of RAS and for the aquaculture industry to help identify physiologically sensitive time stages.
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Van der Westhuyzen, J. G. J., Leuschner, F.W. (2018). The effect of age on white light perception. International Journal of Sustainable Lighting, 20(2), 29–43.
Abstract: The way that persons from different age groups experience “white light” is investigated. Human eye lens transmission changes spectrally with age and this may influence the way that humans from different ages experiences light. Such a difference may be important in industrial and medical environments. Two different age groups, one group younger than 40 years of age and another group older than 50 years of age were subjected to the same “white” definition task.A conventional single-booth setup was used where observers were able to adjust the intensity of four coloured LED’s.Results of the psychophysical test procedure were used to generate specifications of two light sources, as selected by the two age groups. The two age groups selected different light sources when tasked to achieve a “perception” of white. Results show that the older group prefers a source with a colour rendering index number of 89 and the younger group prefers a source with a colour rendering index number of 74. The sources selectedby the two age groups specifycorrelated colour temperature values of 5150 K for the older age group and 6592 K for the younger group.
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Miller, S. D., Straka III, W. C., Yue, J., Seaman, C. J., Xu, S., Elvidge, C. D., et al. (2018). The Dark Side of Hurricane Matthew: Unique Perspectives from the VIIRS Day/Night Band. Bull. Amer. Meteor. Soc., 99(12), 2561–2574.
Abstract: Hurricane Matthew (28 Sep – 9 October 2016) was perhaps the most infamous storm of the 2016 Atlantic hurricane season, claiming over 600 lives and causing over $15 billion USD in damages across the central Caribbean and southeastern U.S. seaboard. Research surrounding Matthew and its many noteworthy meteorological characteristics (e.g., rapid intensification into the southernmost Category 5 hurricane in the Atlantic basin on record, strong lightning and sprite production, and unusual cloud morphology) is ongoing. Satellite remote sensing typically plays an important role in the forecasting and study of hurricanes, providing a top-down perspective on storms developing over the remote and inherently data sparse tropical oceans. In this regard, a relative newcomer among the suite of satellite observations useful for tropical cyclone monitoring and research is the Visible/Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB), a sensor flying onboard the NOAA/NASA Suomi National Polar-orbiting Partnership (SNPP) satellite. Unlike conventional instruments, the DNB's sensitivity to extremely low levels of visible/near-infrared light offers new insight on storm properties and impacts. Here, we chronicle Matthew’s path of destruction and peer through the DNB’s looking glass of low-light visible observations, including lightning connected to sprite formation, modulation of the atmospheric nightglow by storm-generated gravity waves, and widespread power outages. Collected without moonlight, these examples showcase the wealth of unique information present in DNB nocturnal low-light observations without moonlight, and their potential to complement traditional satellite measurements of tropical storms worldwide.
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Fotios, S., & Yao, Q. (2018). The association between correlated colour temperature and scotopic/photopic ratio. Lighting Research & Technology, 35(10), 1365–1374.
Abstract: The scotopic/photopic ratio (S/P) is a parameter that may be considered in the design of road lighting. This paper compares the S/P ratio and correlated colour temperature (CCT) for 297 light source spectra identified in IES Technical Memorandum TM-30-15 to test the assumption that higher S/P ratios demand higher CCTs. The results suggest that, for a given lamp type, there is a strong association between S/P ratio and CCT, and hence that for a given CCT only a small variation in S/P ratio is available. However, the results also suggest that a larger variation in S/P ratio is possible if the lighting designer is able to consider a change in lamp type.
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Yang, M., Ma, N., Zhu, Y., Su, Y. - C., Chen, Q., Hsiao, F. - C., et al. (2018). The Acute Effects of Intermittent Light Exposure in the Evening on Alertness and Subsequent Sleep Architecture. Int J Environ Res Public Health, 15(3).
Abstract: Exposure to bright light is typically intermittent in our daily life. However, the acute effects of intermittent light on alertness and sleep have seldom been explored. To investigate this issue, we employed within-subject design and compared the effects of three light conditions: intermittent bright light (30-min pulse of blue-enriched bright light (~1000 lux, ~6000 K) alternating with 30-min dim normal light (~5 lux, ~3600 K) three times); continuous bright light; and continuous dim light on subjective and objective alertness and subsequent sleep structure. Each light exposure was conducted during the three hours before bedtime. Fifteen healthy volunteers (20 +/- 3.4 years; seven males) were scheduled to stay in the sleep laboratory for four separated nights (one for adaptation and the others for the light exposures) with a period of at least one week between nights. The results showed that when compared with dim light, both intermittent light and continuous bright light significantly increased subjective alertness and decreased sleep efficiency (SE) and total sleep time (TST). Intermittent light significantly increased objective alertness than dim light did during the second half of the light-exposure period. Our results suggested that intermittent light was as effective as continuous bright light in their acute effects in enhancing subjective and objective alertness and in negatively impacting subsequent sleep.
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