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Author Seltmann, S.; Trost, L.; Ter Maat, A.; Gahr, M. url  doi
openurl 
  Title Natural melatonin fluctuation and its minimally invasive simulation in the zebra finch Type Journal Article
  Year 2016 Publication PeerJ Abbreviated Journal  
  Volume 4 Issue Pages e1939  
  Keywords Animals  
  Abstract Melatonin is a key hormone in the regulation of circadian rhythms of vertebrates, including songbirds. Understanding diurnal melatonin fluctuations and being able to reverse or simulate natural melatonin levels are critical to investigating the influence of melatonin on various behaviors such as singing in birds. Here we give a detailed overview of natural fluctuations in plasma melatonin concentration throughout the night in the zebra finch. As shown in previous studies, we confirm that “lights off” initiates melatonin production at night in a natural situation. Notably, we find that melatonin levels return to daytime levels as early as two hours prior to the end of the dark-phase in some individuals and 30 min before “lights on” in all animals, suggesting that the presence of light in the morning is not essential for cessation of melatonin production in zebra finches. Thus, the duration of melatonin production seems not to be specified by the length of night and might therefore be less likely to directly couple circadian and annual rhythms. Additionally, we show that natural melatonin levels can be successfully simulated through a combination of light-treatment (daytime levels during subjective night) and the application of melatonin containing skin-cream (nighttime levels during subjective day). Moreover, natural levels and their fluctuation in the transition from day to night can be imitated, enabling the decoupling of the effects of melatonin, for example on neuronal activity, from sleep and circadian rhythmicity. Taken together, our high-resolution profile of natural melatonin levels and manipulation techniques open up new possibilities to answer various melatonin related questions in songbirds.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title (up) Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2167-8359 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number LoNNe @ kyba @ Serial 1425  
Permanent link to this record
 

 
Author Vozzi, C.; Ramponi, R. url  doi
openurl 
  Title 2015 International Year of Light and beyond Type Magazine Article
  Year 2016 Publication Journal of Optics Abbreviated Journal J. Opt.  
  Volume 18 Issue 1 Pages 010201  
  Keywords Commentary; International Year of Light; IYL; IYL2015; society  
  Abstract The 2015 International Year of Light and Light-based Technologies (IYL) is now approaching its end. It has been a year full of excitement worldwide, involving people of all ages in an incredible number of different activities  
  Address Institute for Photonics and Nanotechnologies (IFN-CNR) Piazza Leonardo da Vinci 32, I-20133 Milan, Italy  
  Corporate Author Thesis  
  Publisher IOP Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title (up) Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2040-8978 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1428  
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Author Buijs, F.N.; Leon-Mercado, L.; Guzman-Ruiz, M.; Guerrero-Vargas, N.N.; Romo-Nava, F.; Buijs, R.M. url  doi
openurl 
  Title The Circadian System: A Regulatory Feedback Network of Periphery and Brain Type Journal Article
  Year 2016 Publication Physiology (Bethesda, Md.) Abbreviated Journal Physiology (Bethesda)  
  Volume 31 Issue 3 Pages 170-181  
  Keywords Human health; circadian rhythm; suprachiasmatic nucleus; brain; clock genes; SCN; review; circadian desynchronization; shiftwork  
  Abstract Circadian rhythms are generated by the autonomous circadian clock, the suprachiasmatic nucleus (SCN), and clock genes that are present in all tissues. The SCN times these peripheral clocks, as well as behavioral and physiological processes. Recent studies show that frequent violations of conditions set by our biological clock, such as shift work, jet lag, sleep deprivation, or simply eating at the wrong time of the day, may have deleterious effects on health. This infringement, also known as circadian desynchronization, is associated with chronic diseases like diabetes, hypertension, cancer, and psychiatric disorders. In this review, we will evaluate evidence that these diseases stem from the need of the SCN for peripheral feedback to fine-tune its output and adjust physiological processes to the requirements of the moment. This feedback can vary from neuronal or hormonal signals from the liver to changes in blood pressure. Desynchronization renders the circadian network dysfunctional, resulting in a breakdown of many functions driven by the SCN, disrupting core clock rhythms in the periphery and disorganizing cellular processes that are normally driven by the synchrony between behavior and peripheral signals with neuronal and humoral output of the hypothalamus. Consequently, we propose that the loss of synchrony between the different elements of this circadian network as may occur during shiftwork and jet lag is the reason for the occurrence of health problems.  
  Address Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, Mexico; ruudbuijs(at)gmail.com  
  Corporate Author Thesis  
  Publisher American Physiological Society Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title (up) Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1548-9221 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:27053731 Approved no  
  Call Number IDA @ john @ Serial 1429  
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Author Lucas, M.A.; Chahl, J.S. url  doi
openurl 
  Title Challenges for biomimetic night time sky polarization navigation Type Conference Article
  Year 2016 Publication Proceedings of the SPIE Abbreviated Journal Proc SPIE  
  Volume 9797 Issue Pages  
  Keywords Animals; detection of light; biology; polarization; navigation  
  Abstract Studies on some species of insects have shown them to use the polarization pattern cast by the moon in the night sky to control heading. Additional heading cues are of value to autonomous systems, since the earth’s magnetic field is not uniform, often not available and is substantially modified by local phenomena. In addition to the required low-light sensitivity of a night time polarization compass, additional complexities caused by the relative intensity of terrestrial sources must be overcome. We will show that the end result will tend to be a less reliable compass than the equivalent day time polarization device.  
  Address Univ. of South Australia, Australia  
  Corporate Author Thesis  
  Publisher SPIE Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title (up) Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1430  
Permanent link to this record
 

 
Author Gómez, C.; Mitchell, C.A. url  openurl
  Title Physiological and Productivity Responses of High-wire Tomato as Affected by Supplemental Light Source and Distribution within the Canopy Type Journal Article
  Year 2016 Publication Journal of the American Society for Horticultural Science Abbreviated Journal J. Amer. Soc. Hort. Sci.  
  Volume 141 Issue 2 Pages 196-208  
  Keywords Plants; tomato; LED; LED lighting; Solanum lycopersicum; intracanopy lighting; greenhouses; intracanopy supplemental lighting; daily light integral  
  Abstract The relative coolness-to-touch of light-emitting diodes (LEDs) has enabled commercial implementation of intracanopy lighting (ICL) in the greenhouse. Intracanopy lighting, which refers to the strategy of lighting along the side or from within the foliar canopy, can increase canopy photosynthetic activity, but physiological and productivity responses of high-wire greenhouse tomato (Solanum lycopersicum) to intracanopy supplemental lighting (SL) still are not yet fully understood. Two consecutive production experiments were conducted across seasons in a glass-glazed greenhouse located in a midnorthern, continental climate [lat. 40°N (West Lafayette, IN)]. Plants were grown from winter-to-summer [increasing solar daily light integral (DLI)] and from summer-to-winter (decreasing solar DLI) to compare three SL strategies for high-wire tomato production across changing solar DLIs: top lighting with high-pressure sodium lamps (HPS) vs. intracanopy LED vertical towers vs. hybrid SL (HPS + horizontal ICL-LEDs). A control treatment also was included for which no SL was provided. Supplemental DLI for each experimental period was adjusted monthly, to complement seasonal changes in sunlight, aiming to approach a target total DLI of 25 mol·m‒2·d‒1 during fruit set. Harvest parameters (total fruit fresh weight, number of fruit harvested, and average cluster fresh weight), tissue temperature, chlorophyll fluorescence, and stomatal conductance (gS) were unaffected by SL treatment in both experiments. Among the physiological parameters evaluated, CO2 assimilation measured under light-saturating conditions, light-limited quantum-use efficiency, and maximum gross CO2 assimilation (Amax) proved to be good indicators of how ICL reduces the top-to-bottom decline in leaf photosynthetic activity otherwise measured with top lighting only (HPS-SL or solar). Although SL generally increased fruit yield relative to control, lack of SL treatment differences among harvest parameters indicates that higher crop photosynthetic activity did not increase fruit yield. Compared with control, intracanopy SL increased yield to the same extent as top SL, but the remaining photoassimilate from ICL most likely was partitioned to maintain nonharvested, vegetative plant parts as well.  
  Address Department of Horticulture and Landscape Architecture, Purdue University, 625 Agriculture Mall Drive, West Lafayette, IN 47907-2010  
  Corporate Author Thesis  
  Publisher American Society for Horticultural Science Place of Publication Editor  
  Language Engligh Summary Language English Original Title  
  Series Editor Series Title (up) Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-1062 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1431  
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