|   | 
Details
   web
Records
Author (up) Bellia, L.; Seraceni, M.
Title A proposal for a simplified model to evaluate the circadian effects of light sources Type Journal Article
Year 2014 Publication Lighting Research and Technology Abbreviated Journal Lighting Research and Technology
Volume 46 Issue 5 Pages 493-505
Keywords Lighting
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1477-1535 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ schroer @ Serial 571
Permanent link to this record
 

 
Author (up) Ben-Attia, M.; Reinberg, A.; Smolensky, M.H.; Gadacha, W.; Khedaier, A.; Sani, M.; Touitou, Y.; Boughamni, N.G.
Title Blooming rhythms of cactus Cereus peruvianus with nocturnal peak at full moon during seasons of prolonged daytime photoperiod Type Journal Article
Year 2016 Publication Chronobiology International Abbreviated Journal Chronobiol Int
Volume 33 Issue 4 Pages 419-430
Keywords Plants; Moonlight
Abstract Cereus peruvianus (Peruvian apple cactus) is a large erect and thorny succulent cactus characterized by column-like (cereus [L]: column), that is, candle-shaped, appendages. For three successive years (1100 days), between early April and late November, we studied the flowering patterns of eight cacti growing in public gardens and rural areas of north and central Tunisia, far from nighttime artificial illumination, in relation to natural environmental light, temperature, relative humidity and precipitation parameters. Flower blooming was assessed nightly between 23:00 h and until at least 02:00 h, and additionally around-the-clock at ~1 h intervals for 30 consecutive days during the late summer of each year of study to quantify both nyctohemeral (day-night) and lunar patterns. During the summer months of prolonged daytime photoperiod, flower blooming of C. peruvianus exhibited predictable-in-time variation as “waves” with average period of 29.5 days synchronized by the light of the full moon. The large-sized flower (~16 cm diameter) opens almost exclusively at night, between sunset and sunrise, as a 24 h rhythm during a specific 3-4-day span of the lunar cycle (full moon), with a strong correlation between moon phase and number and proportion of flowers in bloom (ranging from r = +0.59 to +0.91). Black, blue and red cotton sheets were used to filter specific spectral bands of nighttime moonlight from illuminating randomly selected plant appendages as a means to test the hypothesis of a “gating” 24 h rhythm phenomenon of photoreceptors at the bud level. Relative to control conditions (no light filtering), black sheet covering inhibited flower bud induction by 87.5%, red sheet covering by 46.6% and blue sheet covering by 34%, and the respective inhibiting effects on number of flowers in bloom were essentially 100%, ~81% and ~44%. C. peruvianus is a unique example of a terrestrial plant that exhibits a circadian flowering rhythm (peak ~00:00 h) “gated” by 24 h, lunar 29.5-day (bright light of full moon) and annual 365.25-day (prolonged summertime day length) environmental photoperiod cycles.
Address e Departement des Sciences de la Vie, Faculte des Sciences de Bizerte , Universite de Carthage , Zarzouna , Tunisie
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0742-0528 ISBN Medium
Area Expedition Conference
Notes PMID:27030087 Approved no
Call Number LoNNe @ kyba @ Serial 1411
Permanent link to this record
 

 
Author (up) Benedetto, M.M.; Guido, M.E.; Contin, M.A.
Title Non-Visual Photopigments Effects of Constant Light-Emitting Diode Light Exposure on the Inner Retina of Wistar Rats Type Journal Article
Year 2017 Publication Frontiers in Neurology Abbreviated Journal Front Neurol
Volume 8 Issue Pages 417
Keywords changes in retinal structure; light-emitting diode light; non-visual opsin localization; retinal degeneration models; retinal light damage
Abstract The retina is part of the central nervous system specially adapted to capture light photons and transmit this information to the brain through photosensitive retinal cells involved in visual and non-visual activities. However, excessive light exposure may accelerate genetic retinal diseases or induce photoreceptor cell (PRC) death, finally leading to retinal degeneration (RD). Light pollution (LP) caused by the characteristic use of artificial light in modern day life may accelerate degenerative diseases or promote RD and circadian desynchrony. We have developed a working model to study RD mechanisms in a low light environment using light-emitting diode (LED) sources, at constant or long exposure times under LP conditions. The mechanism of PRC death is still not fully understood. Our main goal is to study the biochemical mechanisms of RD. We have previously demonstrated that constant light (LL) exposure to white LED produces a significant reduction in the outer nuclear layer (ONL) by classical PRC death after 7 days of LL exposure. The PRCs showed TUNEL-positive labeling and a caspase-3-independent mechanism of cell death. Here, we investigate whether constant LED exposure affects the inner-retinal organization and structure, cell survival and the expression of photopigments; in particular we look into whether constant LED exposure causes the death of retinal ganglion cells (RGCs), of intrinsically photosensitive RGCs (ipRGCs), or of other inner-retinal cells. Wistar rats exposed to 200 lx of LED for 2 to 8 days (LL 2 and LL 8) were processed for histological and protein. The results show no differences in the number of nucleus or TUNEL positive RGCs nor inner structural damage in any of LL groups studied, indicating that LL exposure affects ONL but does not produce RGC death. However, the photopigments melanopsin (OPN4) and neuropsin (OPN5) expressed in the inner retina were seen to modify their localization and expression during LL exposure. Our findings suggest that constant light during several days produces retinal remodeling and ONL cell death as well as significant changes in opsin expression in the inner nuclear layer.
Address Centro de Investigaciones en Quimica Biologica de Cordoba (CIQUIBIC), CONICET, Universidad Nacional de Cordoba, Cordoba, Argentina
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1664-2295 ISBN Medium
Area Expedition Conference
Notes PMID:28871236; PMCID:PMC5566984 Approved no
Call Number LoNNe @ kyba @ Serial 1711
Permanent link to this record
 

 
Author (up) Benn, C.R.; Ellison, S.L.
Title La Palma night-sky brightness Type Report
Year 1998 Publication La Palma Technical Reports Abbreviated Journal
Volume Issue 115 Pages
Keywords Skyglow; solar cycle; airglow; zodiacal light; light pollution; observatories; *Light
Abstract The brightness of the moonless night sky above La Palma was measured on 427 CCD images taken with the Isaac Newton and Jacobus Kapteyn Telescopes on 63 nights during 1987 – 1996. The median sky brightness at high elevation, high galactic latitude and high ecliptic latitude, at sunspot minimum, is B = 22.7, V = 21.9, R = 21.0, similar to that at other dark sites. The main contributions to sky brightness are airglow and zodiacal light. The sky is brighter at low ecliptic latitude (by 0.4 mag); at solar maximum (by 0.4 mag); and at high airmass (0.25 mag brighter at airmass 1.5). Light pollution (line + continuum) contributes < 0.03 mag in U, approximately 0.02 mag in B, approximately 0.10 mag in V, approximately and 0.10 mag in R at the zenith.
Address Isaac Newton Group, Apartado 321, 38780 Santa Cruz de La Palma, Spain
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Lots of useful theory on the various contributions to natural sky background level and expected surface brightnesses Approved no
Call Number IDA @ john @ Serial 1101
Permanent link to this record
 

 
Author (up) Bennett, S.; Alpert, M.; Kubulins, V.; Hansler, R.L.
Title Use of modified spectacles and light bulbs to block blue light at night may prevent postpartum depression Type Journal Article
Year 2009 Publication Medical Hypotheses Abbreviated Journal Med Hypotheses
Volume 73 Issue 2 Pages 251-253
Keywords Depression, Postpartum/*prevention & control; *Eyeglasses; Female; Humans; *Lighting; blue light; light therapy; blue blocker
Abstract In 2001 it was discovered that exposing the eyes to light in the blue end of the visible spectrum suppresses the production of the sleep hormone, melatonin. New mothers need to get up during the night to care for their babies. This is the time when melatonin is normally flowing. Exposing their eyes to light can cut off the flow. It may also reset their circadian (internal) clock. On subsequent nights the melatonin may not begin flowing at the normal time making it difficult to fall asleep. Over time, disruption of the circadian rhythm plus sleep deprivation may result in depression. Women suffering postpartum depression were enrolled in a small clinical trial. Some were provided with glasses and light bulbs that block blue light. Others were equipped with glasses and light bulbs that looked colored but did not block the rays causing melatonin suppression. Those with the “real glasses” recovered somewhat more quickly than those with the placebo glasses and light bulbs. The hypothesis that should be tested in large scale clinical trials is that the risk of postpartum depression can be reduced when a new mother avoids exposing her eyes to blue light when she gets up at night to care for her baby. In the meantime, all new mothers may benefit from using glasses and light bulbs that block blue light when getting up at night to care for their babies.
Address Postpartum Support, International P.O. Box 60931, Santa Barbara, CA 93160, USA
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0306-9877 ISBN Medium
Area Expedition Conference
Notes PMID:19329259 Approved no
Call Number IDA @ john @ Serial 296
Permanent link to this record