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Author Arendt, J.; Middleton, B.
Title Human seasonal and circadian studies in Antarctica (Halley, 75 degrees S) Type Journal Article
Year 2018 Publication General and Comparative Endocrinology Abbreviated Journal Gen Comp Endocrinol
Volume 258 Issue Pages 250-258
Keywords Human Activities; Acclimatization/*physiology; Actigraphy; Adult; Antarctic Regions; Behavior/*physiology; Circadian Rhythm/*physiology; Darkness; Female; Heart Rate/physiology; Humans; Libido; Light; Male; Melatonin/blood; Photoperiod; *Seasons; Sleep/physiology; Young Adult; *Antarctica; *Circadian; *Light; *Melatonin; *Seasonal
Abstract Living for extended periods in Antarctica exposes base personnel to extremes of daylength (photoperiod) and temperature. At the British Antarctic Survey base of Halley, 75 degrees S, the sun does not rise for 110 d in the winter and does not set for 100 d in summer. Photoperiod is the major time cue governing the timing of seasonal events such as reproduction in many species. The neuroendocrine signal providing photoperiodic information to body physiology is the duration of melatonin secretion which reflects the length of the night: longer in the short days of winter and shorter in summer. Light of sufficient intensity and spectral composition serves to suppress production of melatonin and to set the circadian timing and the duration of the rhythm. In humans early observations suggested that bright (>2000 lux) white light was needed to suppress melatonin completely. Shortly thereafter winter depression (Seasonal Affective Disorder or SAD) was described, and its successful treatment by an artificial summer photoperiod of bright white light, sufficient to shorten melatonin production. At Halley dim artificial light intensity during winter was measured, until 2003, at a maximum of approximately 500 lux in winter. Thus a strong seasonal and circadian time cue was absent. It seemed likely that winter depression would be common in the extended period of winter darkness and could be treated with an artificial summer photoperiod. These observations, and predictions, inspired a long series of studies regarding human seasonal and circadian status, and the effects of light treatment, in a small overwintering, isolated community, living in the same conditions for many months at Halley. We found little evidence of SAD, or change in duration of melatonin production with season. However the timing of the melatonin rhythm itself, and/or that of its metabolite 6-sulphatoxymelatonin (aMT6s), was used as a primary marker of seasonal, circadian and treatment changes. A substantial phase delay of melatonin in winter was advanced to summer phase by a two pulse 'skeleton' bright white light treatment. Subsequently a single morning pulse of bright white light was effective with regard to circadian phase and improved daytime performance. The circadian delay evidenced by melatonin was accompanied by delayed sleep (logs and actigraphy): poor sleep is a common complaint in Polar regions. Appropriate extra artificial light, both standard white, and blue enriched, present throughout the day, effectively countered delay in sleep timing and the aMT6s rhythm. The most important factor appeared to be the maximum light experienced. Another manifestation of the winter was a decline in self-rated libido (men only on base at this time). Women on the base showed lower aspects of physical and mental health compared to men. Free-running rhythms were seen in some subjects following night shift, but were rarely found at other times, probably because this base has strongly scheduled activity and leisure time. Complete circadian adaptation during a week of night shift, also seen in a similar situation on North Sea oil rigs, led to problems readapting back to day shift in winter, compared to summer. Here again timed light treatment was used to address the problem. Sleep, alertness and waking performance are critically dependent on optimum circadian phase. Circadian desynchrony is associated with increased risk of major disease in shift workers. These studies provide some groundwork for countering/avoiding circadian desynchrony in rather extreme conditions.
Address Biochemistry and Physiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK. Electronic address: b.middleton@surrey.ac.uk
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 0016-6480 ISBN Medium
Area Expedition Conference
Notes PMID:28526480 Approved no
Call Number (down) IDA @ john @ Serial 2248
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Author Huang, Z.; Liu, Q.; Westland, S.; Pointer, M.; Luo, M.R.; Xiao, K.
Title Light dominates colour preference when correlated colour temperature differs Type Journal Article
Year 2018 Publication Lighting Research & Technology Abbreviated Journal Lighting Research & Technology
Volume 50 Issue 7 Pages 995-1012
Keywords Vision; Lighting
Abstract Colour preference for lighting is generally influenced by three kinds of contextual factors, the light, the object and the observer. In this study, a series of psychophysical experiments were conducted to investigate and compare the effect of certain factors on colour preference, including spectral power distribution of light, lighting application, observers’ personal colour preference, regional cultural difference and gender difference. LED lights with different correlated colour temperatures were used to illuminate a wide selection of objects. Participant response was quantified by a 7-point rating method or a 5-level ranking method. It was found that the preferred illumination for different objects exhibited a similar trend and that the influence of light was significantly stronger than that of other factors. Therefore, we conclude that the light itself (rather than, e.g. the objects that are viewed) is the most crucial factor for predicting which light, among several candidates with different correlated colour temperatures, an observer will prefer. In addition, some of the gamut-based colour quality metrics correlated well with the participants’ response, which corroborates the view that colour preference is strongly influenced by colour saturation. The familiarity of the object affects the ratings for each experiment while the colour of the objects also influences colour preference.
Address School of Printing and Packaging, Wuhan University, Luoyu Road 129, Wuhan, China; liuqiang(at)whu.edu.cn
Corporate Author Thesis
Publisher SAGE Place of Publication Editor
Language English Summary Language English 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 (down) IDA @ john @ Serial 2256
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Author Bará, S.; Tapia, C.; Zamorano, J.
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
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 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 (down) IDA @ john @ Serial 2263
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Author Rodrigues, A.L.O.; Rodrigues, A.; Peroff, D.M.
Title The Sky and Sustainable Tourism Development: A Case Study of a Dark Sky Reserve Implementation in Alqueva: The Sky and Sustainable Tourism Development Type Journal Article
Year 2015 Publication International Journal of Tourism Research Abbreviated Journal Int. J. Tourism Res.
Volume 17 Issue 3 Pages 292-302
Keywords Society; light pollution; sustainable tourism; rural tourism; Portugal; Alqueva; Dark Sky Reserve
Abstract This paper shows the development of a tourism product in a destination that uses the night sky as its main source of attraction. Using this innovative product has helped to create a distinctive image, which is likely to attract a more diverse range of visitors and has assisted in improving economic, social and environmental sustainability. First, we present an overview about sustainable tourism and the sky as a tourism resource followed by a case study, in Portugal, that illustrates the potential of Dark Sky activities for tourism development in rural regions.
Address CPES, Lisbon, Portugal; aurea108(at)gmail.com
Corporate Author Thesis
Publisher John Wiley & Sons, Inc. Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1099-2340 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number (down) IDA @ john @ Serial 2286
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Author Gallaway, T.; Olsen, R.N.; Mitchell, D.M.
Title Blinded by the Light: Economic Analysis of Severe Light Pollution Type Journal Article
Year 2013 Publication Journal of Economic Insight Abbreviated Journal J Econ Insight
Volume 39 Issue 1 Pages 45-63
Keywords Economics; light pollution
Abstract This paper examines severe light pollution such as commonly found in large urban areas. Light pollution is the unintended negative consequences of poorly designed and injudiciously used artificial lighting. Light pollution generates significant costs including wasted energy and damage to human health, wildlife, recreation, and the beauty of the night sky. Typically, light-pollution models emphasize population density and ignore economic factors. Economic analysis of the issue has been singularly limited. Previous economic research has focused on widespread, but very low levels of light pollution. This paper makes a unique contribution by analyzing economic factors of severe light pollution. The paper utilizes economic data from the World Bank and unique remote sensing data for 184 countries to quantify the economic causes of severe light pollution. Fractional logit models confirm the importance of population and economic factors alike.
Address Department of Economics, Missouri State University; TerrelGallaway(at)missouristate.edu
Corporate Author Thesis
Publisher Missouri Valley Economic Association Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0361-6576 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number (down) IDA @ john @ Serial 2338
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