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Author Hastings, J. W.; B. M. Sweeney url  openurl
  Title (up) A persistent diurnal rhythm of luminescence in Ganyaulax Polyedra Type Journal Article
  Year 1958 Publication The Biological Bulletin Abbreviated Journal  
  Volume 115 Issue 3 Pages 440-458  
  Keywords Animals  
  Abstract 1. The characteristics of a persistent diurnal rhythm of luminescence in the dinoflagellate Gonyaulax polyedra are described.

2. The light emission upon stimulation, from cultures which are kept in alternating light and dark periods of 12 hours each (= LD), is 40 to 60 times greater during the dark period than during the light period. If LD cultures are placed in continuous dim light (100 foot-candles) a diurnal rhythm of luminescence persists. If LD cultures are placed in continuous bright light (> 1500 foot-candles) the rhythm is damped, and no fluctuations occur in the amount of light emitted.

3. The occurrence of rhythmicity is not dependent upon prior exposure to LD conditions. Cultures which have been grown in bright light for as long as one year show a diurnal rhythm when placed in constant dim light or darkness. Cultures kept in alternating light and dark cycles which are greater or less than 24 hours similarly show a diurnal rhythm when returned to constant dim light or darkness. “Training” or “memory” is therefore not involved.

4. The rhythm can be entrained by light-dark cycles which are different from 24 hours. The period of the luminescence rhythm corresponds to light-dark cycles which have periods ranging between 12 and 32 hours.

5. The period of the rhythm is always close to 24 hours when the cells are kept under constant conditions, but it varies slightly depending upon the temperature and light intensity.

6. The phase of the rhythm under constant conditions is related to the time at which the previous lightand dark periods occurred. Moreover, the phase may be shifted by interposing a non-repeated exposure to a different light intensity. The number of hours by which the phase is shifted in such an experiment is dependent upon the intensity and duration of the light treatment, and the time in the cycle when it is administered.

7. Exhaustive mechanical stimulation does not alter the phase of the rhythm.

8. When cultures having different phases were mixed, no evidence was found which would indicate that there was any interaction between them.

9. The evidence presented indicates that the diurnal rhythmicity is the consequence of a basic oscillatory mechanism which is inherent to the cell.
 
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  Call Number LoNNe @ kagoburian @ Serial 759  
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Author Rayleigh, L. url  doi
openurl 
  Title (up) A Photoelectric Method of Measuring the Light of the Night Sky with Studies of the Course of Variation through the Night Type Journal Article
  Year 1929 Publication Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences Abbreviated Journal Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences  
  Volume 124 Issue 794 Pages 395-408  
  Keywords Instrumentation; Night Sky Brightness  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1364-5021 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2396  
Permanent link to this record
 

 
Author Strutt, R.J. url  doi
openurl 
  Title (up) A photoelectric method of measuring the light of the night sky with studies of the course of variation through the night Type Journal Article
  Year 1929 Publication Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character Abbreviated Journal Proc. R. Soc. Lond. A  
  Volume 124 Issue 794 Pages 395-408  
  Keywords Instrumentation; Natural Sky Brightness; Airglow  
  Abstract The investigations already published on the intensity of the night sky have been made by means of visual photometry, using a convenient instrument with a self-contained luminous source of radioactive origin. Nothing could rival this for simplicity and portability; it is always ready and requires no attention. On the other hand visual photometry is not a very satisfactory process even for ordinary light, and with this faint light it is far from giving the desirable degree of accuracy. I have therefore spent much effort in trying to replace it by some photoelectric method of measurement. A satisfactory method has now been evolved, and will be described, together with the results. A preliminary notice of the earlier results was given in a paper written at the request of Prof. S. Chapman, F. R. S., Chairman of the International Committee on Terrestrial and Solar Relationships, the receipt of which was acknowledged by him on June 19, 1928. The relevant passage is:- “Most of the difficulties have been overcome and preliminary observations have been in progress for some months past. I have been able to follow the changes of intensity from hour to hour on clear nights. Some evidence has been found suggesting diurnal periodicity. The observed intensity nearly always increases between nightfall and midnight, beyond which the observations have not usually been carried.”  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0950-1207 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 3124  
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Author Elvey, C.T.; Roach, F.E. url  doi
openurl 
  Title (up) A Photoelectric Study of the Light from the Night Sky Type Journal Article
  Year 1937 Publication The Astrophysical Journal Abbreviated Journal ApJL  
  Volume 85 Issue Pages 213  
  Keywords Instrumentation; Sky Brightness  
  Abstract  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0004-637X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2399  
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Author Mirzakhalil, S.H.; Bidgoli, S.A. openurl 
  Title (up) A Photographic Investigation of Tehran's Light Pollution from North and East Directions Type Journal Article
  Year 2017 Publication Anthropogenic Pollution Abbreviated Journal  
  Volume 1 Issue 1 Pages 18-24  
  Keywords Skygow  
  Abstract Tehran is the most affected town by light pollution in Iran. In this study, the role of the regional topography in the distribution of light pollution in Tehran was evaluated using digital images recording and analyzing the obtained images from Tehran sky-glow by East and South in standard image-processing Software. The scale of Tehran's glowing =dome as measured by 17 mag/arc sec2 or 0.017 cd/m2 by South, and 18.7 (mag/arc sec2) or 0.0035 cd/m2 by East. Considering the approximately equal distance of the two viewpoints from the center of Tehran city, the calculated scale by South is 1.36 times larger than the amount from the East point.  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 3047  
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