enLIGHTen: IES International Year of Light Photo Contest 2015
In celebration of 2015 as the International Year of Light as proclaimed by UNESCO, the Emerging Professionals of IES (Illuminating Engineering Society) are giving you a reason to share your love for lighting for the next 6 months. Every month we will announce a “Theme of the Month” to which you will post “lighting” photos related to the chosen theme. You can post as many photos as you wish and at the end of each month, for bragging rights only, we will announce our favourite photo of the month. In August, a group of industry professional judges will select the top 3 entrants based on their photo originality, uniqueness, relevance to the theme of the month, activity and interaction with the public.
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The Richard Kelly Grant
2015 Call For Entries - Grant proposals must be submitted by June 30, 2015.
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The Lighting Handbook, 10th Edition
PDF version >
Print version >

Advanced Energy Design Guides: Free Download >

Model Lighting Ordinance – 2011:
Free Download >
Undocumented Changes - Memorandum >

Roadway Lighting Committee Meeting >
March 26 – 27, 2015 | Houston, TX
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LD+A The Magazine of the Illuminating Engineering Society of North America

Lighting Research & Education  

Short-Wavelength Light Can Help Teenagers


Sleep-starved teens may be able to rest easier, according to new research from the Lighting Research Center (LRC) at Rensselaer Polytechnic Institute. The LRC study indicates that exposure to short-wavelength blue light in the morning has the potential to help sleep-deprived adolescents prepare for the challenges of the day and deal with stress. Levels of cortisol, a hormone produced by the adrenal gland, follow a daily 24-hour rhythm. Cortisol concentrations are low throughout the day, reaching a broad minimum in the evening before rising slowly again through the night. In addition to this gradual elevation of cortisol at night, cortisol levels rise sharply within the first 30 to 60 minutes after waking. This is called cortisol awakening response (CAR), and a high CAR has been associated with better preparedness.

LRC’s study included three overnight sessions, at least one week apart. Adolescents aged 12 to 17 wore a dimesimeter to measure light exposure and went to sleep at 1:30 am and woke up at 6:00 am, a 4.5-hour sleep opportunity. Each week, participants either experienced morning short-wavelength blue light or remained in dim light. Results showed that exposure to short-wavelength blue light in the morning significantly enhanced CAR in sleep deprived adolescents, more so than dim light.

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