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Author Zhang, G.; Li, L.; Jiang, Y.; Shen, X.; Li, D.
Title On-Orbit Relative Radiometric Calibration of the Night-Time Sensor of the LuoJia1-01 Satellite Type Journal Article
Year 2018 Publication Sensors (Basel, Switzerland) Abbreviated Journal Sensors (Basel)
Volume 18 Issue 12 Pages
Keywords Instrumentation; Remote Sensing
Abstract The LuoJia1-01 satellite can acquire high-resolution, high-sensitivity nighttime light data for night remote sensing applications. LuoJia1-01 is equipped with a 4-megapixel CMOS sensor composed of 2048 x 2048 unique detectors that record weak nighttime light on Earth. Owing to minute variations in manufacturing and temporal degradation, each detector's behavior varies when exposed to uniform radiance, resulting in noticeable detector-level errors in the acquired imagery. Radiometric calibration helps to eliminate these detector-level errors. For the nighttime sensor of LuoJia1-01, it is difficult to directly use the nighttime light data to calibrate the detector-level errors, because at night there is no large-area uniform light source. This paper reports an on-orbit radiometric calibration method that uses daytime data to estimate the relative calibration coefficients for each detector in the LuoJia1-01 nighttime sensor, and uses the calibrated data to correct nighttime data. The image sensor has a high dynamic range (HDR) mode, which is optimized for day/night imaging applications. An HDR image can be constructed using low- and high-gain HDR images captured in HDR mode. Hence, a day-to-night radiometric reference transfer model, which uses daytime uniform calibration to calibrate the detector non-uniformity of the nighttime sensor, is herein built for LuoJia1-01. Owing to the lack of calibration equipment on-board LuoJia1-01, the dark current of the nighttime sensor is calibrated by collecting no-light desert images at new moon. The results show that in HDR mode (1) the root mean square of mean for each detector in low-gain (high-gain) images is better than 0.04 (0.07) in digital number (DN) after dark current correction; (2) the DN relationship between low- and high-gain images conforms to the quadratic polynomial mode; (3) streaking metrics are better than 0.2% after relative calibration; and (4) the nighttime sensor has the same relative correction parameters at different exposure times for the same gain parameters.
Address State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan 430079, China. drli@whu.edu.cn
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1424-8220 ISBN Medium
Area Expedition Conference
Notes PMID:30513817 Approved no
Call Number GFZ @ kyba @ Serial 2125
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Author Owens, A.C.S.; Lewis, S.M.
Title The impact of artificial light at night on nocturnal insects: A review and synthesis Type Journal Article
Year 2018 Publication Ecology and Evolution Abbreviated Journal Ecol Evol
Volume 8 Issue 22 Pages 11337-11358
Keywords Animals; Review
Abstract In recent decades, advances in lighting technology have precipitated exponential increases in night sky brightness worldwide, raising concerns in the scientific community about the impact of artificial light at night (ALAN) on crepuscular and nocturnal biodiversity. Long-term records show that insect abundance has declined significantly over this time, with worrying implications for terrestrial ecosystems. The majority of investigations into the vulnerability of nocturnal insects to artificial light have focused on the flight-to-light behavior exhibited by select insect families. However, ALAN can affect insects in other ways as well. This review proposes five categories of ALAN impact on nocturnal insects, highlighting past research and identifying key knowledge gaps. We conclude with a summary of relevant literature on bioluminescent fireflies, which emphasizes the unique vulnerability of terrestrial light-based communication systems to artificial illumination. Comprehensive understanding of the ecological impacts of ALAN on diverse nocturnal insect taxa will enable researchers to seek out methods whereby fireflies, moths, and other essential members of the nocturnal ecosystem can coexist with humans on an increasingly urbanized planet.
Address Department of Biology Tufts University Medford Massachusetts
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-7758 ISBN Medium
Area Expedition Conference
Notes PMID:30519447; PMCID:PMC6262936 Approved no
Call Number GFZ @ kyba @ Serial 2132
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Author Chen, Y.; Cheng, M.; Su, T.; Gao, T.; Yu, W.
Title Constant light exposure aggravates POMC-mediated muscle wasting associated with hypothalamic alteration of circadian clock and SIRT1 in endotoxemia rats Type Journal Article
Year 2018 Publication Biochemical and Biophysical Research Communications Abbreviated Journal Biochem Biophys Res Commun
Volume in press Issue Pages
Keywords Animals
Abstract Constant light exposure is widespread in the intensive care unit (ICU) and could increase the rate of brain dysfunction as delirium and sleep disorders in critical patients. And the activation of hypothalamic neuropeptides is proved to play a crucial role in regulating hypercatabolism, especially skeletal muscle wasting in critical patients, which could lead to serious complications and poor prognosis. Here we investigated the hypothesis that constant light exposure could aggravate skeletal muscle wasting in endotoxemia rats and whether it was associated with alterations of circadian clock and hypothalamic proopiomelanocortin(POMC) expression. Fifty-four adult male Sprague-Dawley rats were intraperitoneally injected with lipopolysaccharide(LPS) or saline, subjected to constant light or a 12:12h light-dark cycle for 7 days. On day 8, rats were sacrificed across six time points in 24h and hypothalamus tissues and skeletal muscle were obtained. Rates of muscle wasting were measured by 3-methylhistidine(3-MH) and tyrosine release as well as expression of two muscle atrophic genes, muscle ring finger 1(MuRF-1) and muscle atrophy F-box(MAFbx). The expression of circadian clock genes, silent information regulator 1(SIRT1), POMC and hypothalamic inflammatory cytokines were also detected. Results showed that LPS administration significantly increased hypothalamic POMC expression, inflammatory cytokine levels and muscle wasting rates. Meanwhile constant light exposure disrupted the circadian rhythm, declined the expression of SIRT1 as well as aggravated hypothalamic POMC overexpression and skeletal muscle wasting in rats with endotoxemia. Taken together, the results demonstrated that constant light exposure could aggravate POMC-mediated skeletal muscle wasting in endotoxemia rats, which is associated with alteration of circadian clocks and SIRT1 in the hypothalamus.
Address Department of Intensive Care Unit, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, 210008, China. Electronic address: yudrnj2@163.com
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0006-291X ISBN Medium
Area Expedition Conference
Notes PMID:30528733 Approved no
Call Number GFZ @ kyba @ Serial 2134
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Author Masri, S.; Sassone-Corsi, P.
Title The emerging link between cancer, metabolism, and circadian rhythms Type Journal Article
Year 2018 Publication Nature Medicine Abbreviated Journal Nat Med
Volume 24 Issue 12 Pages 1795-1803
Keywords Human Health; Review
Abstract The circadian clock is a complex cellular mechanism that, through the control of diverse metabolic and gene expression pathways, governs a large array of cyclic physiological processes. Epidemiological and clinical data reveal a connection between the disruption of circadian rhythms and cancer that is supported by recent preclinical data. In addition, results from animal models and molecular studies underscore emerging links between cancer metabolism and the circadian clock. This has implications for therapeutic approaches, and we discuss the possible design of chronopharmacological strategies.
Address Department of Biological Chemistry, Center for Epigenetics and Metabolism, INSERM U1233, University of California Irvine, Irvine, CA, USA. psc@uci.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1078-8956 ISBN Medium
Area Expedition Conference
Notes PMID:30523327 Approved no
Call Number GFZ @ kyba @ Serial 2135
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Author Halfwerk, W.; Blaas, M.; Kramer, L.; Hijner, N.; Trillo, P.A.; Bernal, X.E.; Page, R.A.; Goutte, S.; Ryan, M.J.; Ellers, J.
Title Adaptive changes in sexual signalling in response to urbanization Type Journal Article
Year 2018 Publication Nature Ecology & Evolution Abbreviated Journal Nat Ecol Evol
Volume 3 Issue Pages 374-380
Keywords Animals
Abstract Urbanization can cause species to adjust their sexual displays, because the effectiveness of mating signals is influenced by environmental conditions. Despite many examples that show that mating signals in urban conditions differ from those in rural conditions, we do not know whether these differences provide a combined reproductive and survival benefit to the urban phenotype. Here we show that male tungara frogs have increased the conspicuousness of their calls, which is under strong sexual and natural selection by signal receivers, as an adaptive response to city life. The urban phenotype consequently attracts more females than the forest phenotype, while avoiding the costs that are imposed by eavesdropping bats and midges, which we show are rare in urban areas. Finally, we show in a translocation experiment that urban frogs can reduce risk of predation and parasitism when moved to the forest, but that forest frogs do not increase their sexual attractiveness when moved to the city. Our findings thus reveal that urbanization can rapidly drive adaptive signal change via changes in both natural and sexual selection pressures.
Address Department of Ecological Science, Vrije Universiteit, Amsterdam, The Netherlands
Corporate Author Thesis
Publisher Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2397-334X ISBN Medium
Area Expedition Conference
Notes PMID:30532046 Approved no
Call Number GFZ @ kyba @ Serial 2136
Permanent link to this record