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Author Rahman, S.A.; St Hilaire, M.A.; Gronfier, C.; Chang, A.-M.; Santhi, N.; Czeisler, C.A.; Klerman, E.B.; Lockley, S.W. url  doi
openurl 
  Title (up) Functional decoupling of melatonin suppression and circadian phase resetting in humans Type Journal Article
  Year 2018 Publication The Journal of Physiology Abbreviated Journal J Physiol  
  Volume 596 Issue 11 Pages 2147-2157  
  Keywords Human Health  
  Abstract KEY POINTS: There is assumed to be a monotonic association between melatonin suppression and circadian phase resetting induced by light exposure. We tested the association between melatonin suppression and phase resetting in humans. Sixteen young healthy participants received nocturnal bright light ( approximately 9500 lux) exposure of continuous or intermittent patterns, and different durations ranging from 12 min to 6.5 h. Intermittent exposure patterns showed significant phase shifts with disproportionately less melatonin suppression. Each and every bright light stimulus in an intermittent exposure pattern induced a similar degree of melatonin suppression, but did not appear to cause an equal magnitude of phase shift. These results suggest that phase shifts and melatonin suppression are functionally independent such that one cannot be used as a proxy measure of the other. ABSTRACT: Continuous experimental light exposures show that, in general, the conditions that produce greater melatonin suppression also produce greater phase shift, leading to the assumption that one can be used as a proxy for the other. We tested this association in 16 healthy individuals who participated in a 9-day inpatient protocol by assessing melatonin suppression and phase resetting in response to a nocturnal light exposure (LE) of different patterns: (i) dim-light control (<3 lux; n = 6) or (ii) two 12-min intermittent bright light pulses (IBL) separated by 36 min of darkness ( approximately 9500 lux; n = 10). We compared these results with historical data from additional LE patterns: (i) dim-light control (<3 lux; n = 11); (ii) single continuous bright light exposure of 12 min (n = 9), 1.0 h (n = 10) or 6.5 h (n = 6); or (iii) an IBL light pattern consisting of six 15-min pulses with 1.0 h dim-light recovery intervals between them during a total of 6.5 h (n = 7). All light exposure groups had significantly greater phase-delay shifts than the dim-light control condition (P < 0.0001). While a monotonic association between melatonin suppression and circadian phase shift was observed, intermittent exposure patterns showed significant phase shifts with disproportionately less melatonin suppression. Each and every IBL stimulus induced a similar degree of melatonin suppression, but did not appear to cause an equal magnitude of phase shift. These results suggest unique specificities in how light-induced phase shifts and melatonin suppression are mediated such that one cannot be used as a proxy measure of the other.  
  Address Division of Sleep Medicine, Harvard Medical School, Boston, MA, 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 0022-3751 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:29707782 Approved no  
  Call Number GFZ @ kyba @ Serial 1887  
Permanent link to this record
 

 
Author Ge, W.; Yang, H.; Zhu, X.; Ma, M.; Yang, Y. url  doi
openurl 
  Title (up) Ghost City Extraction and Rate Estimation in China Based on NPP-VIIRS Night-Time Light Data Type Journal Article
  Year 2018 Publication ISPRS International Journal of Geo-Information Abbreviated Journal Ijgi  
  Volume 7 Issue 6 Pages 219  
  Keywords Remote Sensing  
  Abstract The ghost city phenomenon is a serious problem resulting from the rapid urbanization process in China. Estimation of the ghost city rate (GCR) can provide information about vacant dwellings. This paper developed a methodology to quantitatively evaluate GCR values at the national scale using multi-resource remote sensing data. The Suomi National Polar-Orbiting Partnership–Visible Infrared Imaging Radiometer (NPP-VIIRS) night-time light data and moderate resolution imaging spectroradiometer (MODIS) land cover data were used in the evaluation of the GCR values in China. The average ghost city rate (AGCR) was 35.1% in China in 2013. Shanghai had the smallest AGCR of 21.7%, while Jilin has the largest AGCR of 47.27%. There is a significant negative correlation between both the provincial AGCR and the per capita disposable income of urban households (R = −0.659, p < 0.01) and the average selling prices of commercial buildings (R =−0.637, p < 0.01). In total, 31 ghost cities are mainly concentrated in the economically underdeveloped inland provinces. Ghost city areas are mainly located on the edge of urban built-up areas, and the spatial pattern of ghost city areas changed in different regions. This approach combines statistical data with the distribution of vacant urban areas, which is an effective method to capture ghost city information.  
  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 2220-9964 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1949  
Permanent link to this record
 

 
Author Ernst, S.; Łabuz, M.; Środa, K.; Kotulski, L. url  doi
openurl 
  Title (up) Graph-Based Spatial Data Processing and Analysis for More Efficient Road Lighting Design Type Journal Article
  Year 2018 Publication Sustainability Abbreviated Journal Sustainability  
  Volume 10 Issue 11 Pages 3850  
  Keywords Lighting  
  Abstract The efficiency and affordability of modern street lighting equipment are improving quickly, but systems used to manage and design lighting installations seem to lag behind. One of their problems is the lack of consistent methods to integrate all relevant data. Tools used to manage lighting infrastructure are not aware of the geographic characteristics of the lit areas, and photometric calculation software requires a lot of manual editing by the designer, who needs to assess the characteristics of roads, define the segments, and assign the lighting classes according to standards. In this paper, we propose a graph-based method to integrate geospatial data from various sources to support the process of data preparation for photometric calculations. The method uses graph transformations to define segments and assign lighting classes. A prototype system was developed to conduct experiments using real-world data. The proposed approach is compared to results obtained by professional designers in a case study; the method was also applied to several European cities to assess its efficiency. The obtained results are much more fine-grained than those yielded by the traditional approach; as a result, the lighting is more adequate, especially when used in conjunction with automated optimisation tools.  
  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 2071-1050 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2051  
Permanent link to this record
 

 
Author Wilson IV, J.; Reid, K.J.; Braun, R.I.; Abbott, S.M.; Zee, P.C. url  doi
openurl 
  Title (up) Habitual Light Exposure Relative to Circadian Timing in Delayed Sleep-Wake Phase Disorder Type Journal Article
  Year 2018 Publication Sleep Abbreviated Journal  
  Volume in press Issue Pages  
  Keywords Human Health  
  Abstract Study Objectives

To compare melatonin timing, a well validated marker for endogenous circadian phase, and habitual light exposure patterns in adults with delayed sleep-wake phase disorder (DSWPD) and intermediate chronotype controls.

Methods

12 individuals with DSWPD (5 females, mean age 31.1) and 12 age matched controls (6 females, mean age 33.6) underwent a minimum of seven days of light and activity monitoring followed by an inpatient hospital stay, where blood was taken to assess melatonin timing (calculated as dim light melatonin onset – DLMO). Habitual light exposure patterns were then compared to a human phase response curve (PRC) to light.

Results

Relative to clock time, individuals with DSWPD had a later light exposure pattern compared to controls, but their light exposure pattern was earlier relative to DLMO. According to the human phase response curve (PRC) to light, individuals with DSWPD had less daily advancing light exposure compared to controls. The primary difference was seen in the late portion of the advancing window, in which individuals with DSWPD were exposed to fewer pulses of light of equivalent duration and intensity compared to controls.

Conclusions

Diminished advancing light exposure may play a role in the development and perpetuation of delayed sleep-wake timing in individuals with DSWPD. Enhancing light exposure during the later portion of the advancing window represents an innovative and complementary strategy that has the potential to improve the effectiveness of bright light therapy in DSWPD.
 
  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 0161-8105 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1990  
Permanent link to this record
 

 
Author Wittenbrink, N.; Ananthasubramaniam, B.; Munch, M.; Koller, B.; Maier, B.; Weschke, C.; Bes, F.; de Zeeuw, J.; Nowozin, C.; Wahnschaffe, A.; Wisniewski, S.; Zaleska, M.; Bartok, O.; Ashwal-Fluss, R.; Lammert, H.; Herzel, H.; Hummel, M.; Kadener, S.; Kunz, D.; Kramer, A. url  doi
openurl 
  Title (up) High-accuracy determination of internal circadian time from a single blood sample Type Journal Article
  Year 2018 Publication The Journal of Clinical Investigation Abbreviated Journal J Clin Invest  
  Volume 128 Issue 9 Pages 3826-3839  
  Keywords Human Health  
  Abstract BACKGROUND: The circadian clock is a fundamental and pervasive biological program that coordinates 24-hour rhythms in physiology, metabolism, and behavior, and it is essential to health. Whereas therapy adapted to time of day is increasingly reported to be highly successful, it needs to be personalized, since internal circadian time is different for each individual. In addition, internal time is not a stable trait, but is influenced by many factors, including genetic predisposition, age, sex, environmental light levels, and season. An easy and convenient diagnostic tool is currently missing. METHODS: To establish a validated test, we followed a 3-stage biomarker development strategy: (a) using circadian transcriptomics of blood monocytes from 12 individuals in a constant routine protocol combined with machine learning approaches, we identified biomarkers for internal time; and these biomarkers (b) were migrated to a clinically relevant gene expression profiling platform (NanoString) and (c) were externally validated using an independent study with 28 early or late chronotypes. RESULTS: We developed a highly accurate and simple assay (BodyTime) to estimate the internal circadian time in humans from a single blood sample. Our assay needs only a small set of blood-based transcript biomarkers and is as accurate as the current gold standard method, dim-light melatonin onset, at smaller monetary, time, and sample-number cost. CONCLUSION: The BodyTime assay provides a new diagnostic tool for personalization of health care according to the patient's circadian clock. FUNDING: This study was supported by the Bundesministerium fur Bildung und Forschung, Germany (FKZ: 13N13160 and 13N13162) and Intellux GmbH, Germany.  
  Address Charite Universitatsmedizin Berlin, corporate member of Freie Universitat Berlin, Humboldt-Universitat zu Berlin, and Berlin Institute of Health, Laboratory of Chronobiology, Berlin, Germany  
  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 0021-9738 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:29953415; PMCID:PMC6118629 Approved no  
  Call Number GFZ @ kyba @ Serial 2194  
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