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Author (up) Aubé, M.; Roby, J.; Kocifaj, M.
Title Evaluating potential spectral impacts of various artificial lights on melatonin suppression, photosynthesis, and star visibility Type Journal Article
Year 2013 Publication PloS one Abbreviated Journal PLoS One
Volume 8 Issue 7 Pages e67798
Keywords Humans; *Light; Lighting/methods; Melatonin/*metabolism; Photosynthesis/*radiation effects; Plant Development/radiation effects; blue light; circadian disruption
Abstract Artificial light at night can be harmful to the environment, and interferes with fauna and flora, star visibility, and human health. To estimate the relative impact of a lighting device, its radiant power, angular photometry and detailed spectral power distribution have to be considered. In this paper we focus on the spectral power distribution. While specific spectral characteristics can be considered harmful during the night, they can be considered advantageous during the day. As an example, while blue-rich Metal Halide lamps can be problematic for human health, star visibility and vegetation photosynthesis during the night, they can be highly appropriate during the day for plant growth and light therapy. In this paper we propose three new indices to characterize lamp spectra. These indices have been designed to allow a quick estimation of the potential impact of a lamp spectrum on melatonin suppression, photosynthesis, and star visibility. We used these new indices to compare various lighting technologies objectively. We also considered the transformation of such indices according to the propagation of light into the atmosphere as a function of distance to the observer. Among other results, we found that low pressure sodium, phosphor-converted amber light emitting diodes (LED) and LED 2700 K lamps filtered with the new Ledtech's Equilib filter showed a lower or equivalent potential impact on melatonin suppression and star visibility in comparison to high pressure sodium lamps. Low pressure sodium, LED 5000 K-filtered and LED 2700 K-filtered lamps had a lower impact on photosynthesis than did high pressure sodium lamps. Finally, we propose these indices as new standards for the lighting industry to be used in characterizing their lighting technologies. We hope that their use will favor the design of new environmentally and health-friendly lighting technologies.
Address Departement de physique, Cegep de Sherbrooke, Sherbrooke, Quebec, Canada. martin.aube@cegepsherbrooke.qc.ca
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Publisher Place of Publication Editor
Language English Summary Language Original Title
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Series Volume Series Issue Edition
ISSN 1932-6203 ISBN Medium
Area Expedition Conference
Notes PMID:23861808; PMCID:PMC3702543 Approved no
Call Number IDA @ john @ Serial 282
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Author (up) Özyürek, C.; Aydin, G.
Title Students’ Opinions on the Light Pollution Application Type Journal Article
Year 2015 Publication International Electronic Journal of Elementary Education Abbreviated Journal IEJEE
Volume 8 Issue 1 Pages 55-68
Keywords Society; awareness; perception; education; child development; light pollution
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.
Address Ordu University, Turkey
Corporate Author Thesis
Publisher T&K Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1307-9298 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1288
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Author (up) Camus, Thomas; Zeng, Chaoshu
Title Effects of photoperiod on egg production and hatching success, naupliar and copepodite development, adult sex ratio and life expectancy of the tropical calanoid copepod Acartia sinjiensis Type Journal Article
Year 2008 Publication Aquaculture Abbreviated Journal
Volume 280 Issue 1-4 Pages 220-226
Keywords animals; Acartia sinjiensis; Egg production and hatching success; Life expectancy; Naupliar and copepodite development; Photoperiod; Sex ratio
Abstract The tropical calanoid copepod Acartia sinjiensis has good potential for mass culture as live feed for reef fish larvae. The present study was conducted to evaluate the effects of photoperiod on various parameters related to A. sinjiensis productivity in culture. Five photoperiods of Light:Dark = 0:24; 6:18; 12:12; 18:6 and 24:0h were setup. Daily egg production of individual females under each photoperiod was monitored for 8 consecutive days. The females were randomly selected daily from stock cultures kept under respective photoperiods and discarded after experiment. The results showed a clear trend of increasing egg production with longer illumination period. Under constant darkness, acclimatization was evident as egg output increased steadily over the 8??day period. Statistics showed that photoperiod significantly (p < 0.005) affected mean daily egg production, with the highest egg output recorded at 18L:6D and 24L:0D (17.6 ?? 1.7 and 17.6 ?? 1.8 eggs/female/day respectively), which were significantly higher than all other treatments. Photoperiod also significantly affected 48??h egg hatching success (p < 0.005), a trend of increased hatching success with longer light phase was demonstrated. The highest hatching rate (87.2 ?? 1.4%) was recorded at 24L:0D, which was significantly higher than the 0L:24D and 6L:18D treatments but not significantly different from the second highest (85.3 ?? 2.6%) hatching rate of 18L:6D treatment. Photoperiod was further confirmed to significantly (p < 0.005) affected naupliar and copepodite development with accelerated development observed with increased illumination period of photoperiods. Mean development time from egg to adult was the shortest at 6.00 ?? 0.33 days under constant light (24L:0D), followed by 6.24 ?? 0.24??days at 18L:6D, both were significantly shorter than that of 0L:24D and 6L:18D treatments although no significantly difference was detected between themselves. Adult life expectancy was also found significantly (p < 0.005) affected by photoperiod with the shortest adult life span recorded under constant light (24L:0D) (9.4 ?? 0.4??days), which was significantly shorter than all other photoperiods tested. Adult sex ratio was the only parameter tested that was not significantly affected by photoperiod, a skewed sex ratio in favor of female was found across all photoperiod treatments. Based on results of current study, it is recommended that a photoperiod of 18L:6D being adopted for A. sinjiensis culture to maximize its productivity for aquaculture hatcheries.
Address
Corporate Author Thesis
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Language Summary Language Original Title
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Notes Approved no
Call Number LoNNe @ schroer @ Serial 1581
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Author (up) Elvidge, C.D.; Baugh, K.E.; Anderson, S.J.; Sutton, P.C.; Ghosh, T.
Title The Lumen Gini Coefficient: a satellite imagery derived human development index Type Journal Article
Year 2012 Publication Social Geography Discussions Abbreviated Journal Soc. Geogr. Discuss.
Volume 8 Issue 1 Pages 27-59
Keywords Gini coefficient; light at night; remote sensing; economics; development
Abstract The “Lumen Gini Coefficient” is a simple, objective, spatially explicit and globally available empirical measurement of human development derived solely from nighttime satellite imagery and population density. There is increasing recognition that the distribution of wealth and income amongst the population in a nation or region correlates strongly with both the overall happiness of that population and the environmental quality of that nation or region. Measuring the distribution of wealth and income at national and regional scales is an interesting and challenging problem. Gini coefficients derived from Lorenz curves are a well-established method of measuring income distribution. Nonetheless, there are many shortcomings of the Gini coefficient as a measure of income or wealth distribution. Gini coefficients are typically calculated using national level data on the distribution of income through the population. Such data are not available for many countries and the results are generally limited to single values representing entire countries. In this paper we develop an alternative measure of the distribution of “human development”, called the “Lumen Gini coefficient”, that is derived without the use of monetary measures of wealth and is capable of providing a spatial depiction of differences in development within countries.
Address NOAA National Geophysical Data Center, Boulder, Colorado, USA
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Language Summary Language Original Title
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ISSN 1816-1502 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 216
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Author (up) Elvidge, C.D.; Sutton, P.C.; Ghosh, T.; Tuttle, B.T.; Baugh, K.E.; Bhaduri, B.; Bright, E.
Title A global poverty map derived from satellite data Type Journal Article
Year 2009 Publication Computers & Geosciences Abbreviated Journal Computers & Geosciences
Volume 35 Issue 8 Pages 1652-1660
Keywords Poverty; DMSP; Nighttime lights; World development indicators; light pollution
Abstract A global poverty map has been produced at 30 arcsec resolution using a poverty index calculated by dividing population count (LandScan 2004) by the brightness of satellite observed lighting (DMSP nighttime lights). Inputs to the LandScan product include satellite-derived land cover and topography, plus human settlement outlines derived from high-resolution imagery. The poverty estimates have been calibrated using national level poverty data from the World Development Indicators (WDI) 2006 edition. The total estimate of the numbers of individuals living in poverty is 2.2 billion, slightly under the WDI estimate of 2.6 billion. We have demonstrated a new class of poverty map that should improve over time through the inclusion of new reference data for calibration of poverty estimates and as improvements are made in the satellite observation of human activities related to economic activity and technology access.
Address
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0098-3004 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 123
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