toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Bará, S.; Tapia, C.; Zamorano, J. url  doi
openurl 
  Title Absolute Radiometric Calibration of TESS-W and SQM Night Sky Brightness Sensors Type Journal Article
  Year 2019 Publication Sensors Abbreviated Journal Sensors  
  Volume 19 Issue 6 Pages 1336  
  Keywords Instrumentation; calibration; SQM; TESS; photometer; sky brightness  
  Abstract We develop a general optical model and describe the absolute radiometric calibration of the readings provided by two widely-used night sky brightness sensors based on irradiance-to-frequency conversion. The calibration involves the precise determination of the overall spectral sensitivity of the devices and also the constant G relating the output frequency of the light-to-frequency converter chip to the actual band-weighted and field-of-view averaged spectral radiance incident on the detector (brightness). From these parameters, we show how to define a rigorous astronomical absolute photometric system in which the sensor measurements can be reported in units of magnitudes per square arcsecond with precise physical meaning.  
  Address (down) Departmento Física Aplicada, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Galicia, Spain; salva.bara(at)usc.es  
  Corporate Author Thesis  
  Publisher MDPI Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1424-8220 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 2263  
Permanent link to this record
 

 
Author Kumar, J.; Malik, S.; Bhardwaj, S.K.; Rani, S. url  doi
openurl 
  Title Bright light at night alters the perception of daylength in Indian weaver bird (Ploceus philippinus) Type Journal Article
  Year 2018 Publication Journal of Experimental Zoology. Part A, Ecological and Integrative Physiology Abbreviated Journal J Exp Zool A Ecol Integr Physiol  
  Volume 329 Issue 8-9 Pages 488-496  
  Keywords Animals  
  Abstract The brighter nights have posed new challenges to the wild species by affecting their temporal physiology. The present study on Indian weaver bird (Ploceus philippinus) investigated if exposure to bright light at different phases of night affects their clock-mediated daily functions. Birds were placed individually in specially designed activity cages under short days and long nights (8L:16D; L = 100 lux, D < 0.1 lux) for approximately 3 weeks (19 days). Thereafter, they were divided into four groups (n = 6-9), and given approximately 2 lux light either for the entire night (ZT 08-24; zeitgeber time 0 = time of light on; pattern A) or for 4 hr (pattern B), placed in 16 hr night such that its onset coincides with the onset of night (early night group, ZT 08-12), its end with the end of night (late night group, ZT 20-24), or the night was interrupted in the middle (midnight group, ZT 14-18). The results showed that bright light in entire night induced early onset of day activity and fragmented rest at night, however, if given at different phases of night, it made the days longer by delaying end (early night group) or advancing onset of daily activity (late night group). It also suppressed the melatonin levels and increased body temperature. These results suggest that bright light at night alters the perception of daylength and affects the underlying physiology. The findings may be useful in adopting a strategy for use of night light without disturbing species fitness in their environment.  
  Address (down) Department of Zoology, University of Lucknow, Lucknow, India  
  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 2471-5638 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30043408 Approved no  
  Call Number GFZ @ kyba @ Serial 1971  
Permanent link to this record
 

 
Author Taufique, S.T.; Prabhat, A.; Kumar, V. url  doi
openurl 
  Title Light at night affects hippocampal and nidopallial cytoarchitecture: Implication for impairment of brain function in diurnal corvids Type Journal Article
  Year 2018 Publication Journal of Experimental Zoology. Part A, Ecological and Integrative Physiology Abbreviated Journal J Exp Zool A Ecol Integr Physiol  
  Volume in press Issue Pages in press  
  Keywords Animals  
  Abstract Our previous studies have shown that light at night (LAN) impaired cognitive performance and affected neurogenesis and neurochemistry in the cognition-associated brain regions, particularly the hippocampus (HP) and lateral caudal nidopallium (NCL) of Indian house crows (Corvus splendens). Here, we examined the cytoarchitecture and mapped out the morphology of neurons and glia-neuron density in HP and NCL regions of crows that were first entrained to 12-hr light (LL): 12-hr darkness (LD) and then exposed to the light regime in which 12-hr darkness was either replaced by daytime light (i.e., constant light, LL) or by dim light (i.e., dim light at night, dLAN), with controls continued on LD 12:12. Compared with LD, there was a significant decrease in the soma size, suggesting reduced neuronal plasticity without affecting the neuronal density of both HP and NCL of crows under LL and dLAN conditions. In parallel, we found a reduced number of glia cells and, hence, decreased glia-neuron ratio positively correlated with soma size in both, HP and NCL regions. These results for the first time demonstrate LAN-induced negative effects on the brain cytoarchitecture of a diurnal species and give insight for possible influence on the brain health and functions in animals including humans that might be inadvertently exposed to LAN in an emerging night-illuminated urban environment.  
  Address (down) Department of Zoology, University of Delhi, Delhi, India  
  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 2471-5638 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30288960 Approved no  
  Call Number GFZ @ kyba @ Serial 2022  
Permanent link to this record
 

 
Author Batra, T.; Malik, I.; Prabhat, A.; Bhardwaj, S.K.; Kumar, V. url  doi
openurl 
  Title Sleep in unnatural times: illuminated night negatively affects sleep and associated hypothalamic gene expressions in diurnal zebra finches Type Journal Article
  Year 2020 Publication Proceedings. Biological Sciences Abbreviated Journal Proc Biol Sci  
  Volume 287 Issue 1928 Pages 20192952  
  Keywords Animals; bird; dim light at night; gene expression; hypothalamus; sleep; zebra finch  
  Abstract We investigated the effects of exposure at ecologically relevant levels of dim light at night (dLAN) on sleep and the 24 h hypothalamic expression pattern of genes involved in the circadian timing (per2, bmal1, reverb-beta, cry1, ror-alpha, clock) and sleep regulatory pathways (cytokines: tlr4, tnf-alpha, il-1beta, nos; Ca(2+)-dependent pathway: camk2, sik3, nr3a; cholinergic receptor, achm3) in diurnal female zebra finches. Birds were exposed to 12 h light (150 lux) coupled with 12 h of absolute darkness or of 5 lux dim light for three weeks. dLAN fragmented the nocturnal sleep in reduced bouts, and caused sleep loss as evidenced by reduced plasma oxalate levels. Under dLAN, the 24 h rhythm of per2, but not bmal1 or reverb-beta, showed a reduced amplitude and altered peak expression time; however, clock, ror-alpha and cry1 expressions showed an abolition of the 24 h rhythm. Decreased tlr4, il-1beta and nos, and the lack of diurnal difference in achm3 messenger RNA levels suggested an attenuated inhibition of the arousal system (hence, awake state promotion) under dLAN. Similarly, changes in camk2, sik3 and nr3a expressions suggested dLAN-effects on Ca(2+)-dependent sleep-inducing pathways. These results demonstrate dLAN-induced negative effects on sleep and associated hypothalamic molecular pathways, and provide insights into health risks of illuminated night exposures to diurnal animals.  
  Address (down) Department of Zoology, University of Delhi, Delhi 110 007, India  
  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 0962-8452 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:32517617 Approved no  
  Call Number GFZ @ kyba @ Serial 2995  
Permanent link to this record
 

 
Author Hines, C.W.; Fang, Y.; Chan, V.K.S.; Stiller, K.T.; Brauner, C.J.; Richards, J.G. url  doi
openurl 
  Title The effect of salinity and photoperiod on thermal tolerance of Atlantic and coho salmon reared from smolt to adult in recirculating aquaculture systems Type Journal Article
  Year 2018 Publication Comparative Biochemistry and Physiology. Part A, Molecular & Integrative Physiology Abbreviated Journal Comp Biochem Physiol A Mol Integr Physiol  
  Volume 230 Issue Pages 1-6  
  Keywords Animals  
  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.  
  Address (down) Department of Zoology, The University of British Columbia, 6270 University Blvd., Vancouver, BC V6T 1Z4, Canada  
  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 1095-6433 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30590111 Approved no  
  Call Number GFZ @ kyba @ Serial 2149  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: