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Author Zhang, G.; Li, L.; Jiang, Y.; Shen, X.; Li, D. url  doi
openurl 
  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 (down) 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 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  
Permanent link to this record
 

 
Author Zhen, J.; Pei, T.; Xie, S. url  doi
openurl 
  Title Kriging methods with auxiliary nighttime lights data to detect potentially toxic metals concentrations in soil Type Journal Article
  Year 2019 Publication The Science of the Total Environment Abbreviated Journal Sci Total Environ  
  Volume 659 Issue Pages 363-371  
  Keywords Remote Sensing  
  Abstract The spatial distribution of potentially toxic metals (PTMs) has been shown to be related to anthropogenic activities. Several auxiliary variables, such as those related to remote sensing data (e.g. digital elevation models, land use, and enhanced vegetation index) and soil properties (e.g. pH, soil type and cation exchange capacity), have been used to predict the spatial distribution of soil PTMs. However, these variables are mostly focused on natural processes or a single aspect of anthropogenic activities and cannot reflect the effects of integrated anthropogenic activities. Nighttime lights (NTL) images, a representative variable of integrated anthropogenic activities, may have the potential to reflect PTMs distribution. To uncover this relationship and determine the effects on evaluation precision, the NTL was employed as an auxiliary variable to map the distribution of PTMs in the United Kingdom. In this study, areas with a digital number (DN)>/=50 and an area>30km(2) were extracted from NTL images to represent regions of high-frequency anthropogenic activities. Subsequently, the distance between the sampling points and the nearest extracted area was calculated. Barium, lead, zinc, copper, and nickel concentrations exhibited the highest correlation with this distance. Their concentrations were mapped using distance as an auxiliary variable through three different kriging methods, i.e., ordinary kriging (OK), cokriging (CK), and regression kriging (RK). The accuracy of the predictions was evaluated using the leave-one-out cross validation method. Regardless of the elements, CK and RK always exhibited lower mean absolute error and root mean square error, in contrast to OK. This indicates that using the NTL as the auxiliary variable indeed enhanced the prediction accuracy for the relevant PTMs. Additionally, RK showed superior results in most cases. Hence, we recommend RK for prediction of PTMs when using the NTL as the auxiliary variable.  
  Address (down) State Key Laboratory of Geological Processes and Mineral Resources(GPMR), Faculty of Earth Sciences, China University of Geosciences, Wuhan, 430074, China  
  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 0048-9697 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30599355 Approved no  
  Call Number GFZ @ kyba @ Serial 2494  
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Author Kaplan, K.A.; Mashash, M.; Williams, R.; Batchelder, H.; Starr-Glass, L.; Zeitzer, J.M. url  doi
openurl 
  Title Effect of Light Flashes vs Sham Therapy During Sleep With Adjunct Cognitive Behavioral Therapy on Sleep Quality Among Adolescents: A Randomized Clinical Trial Type Journal Article
  Year 2019 Publication JAMA Network Open Abbreviated Journal JAMA Netw Open  
  Volume 2 Issue 9 Pages e1911944  
  Keywords Human Health  
  Abstract Importance: Owing to biological, behavioral, and societal factors, sleep duration in teenagers is often severely truncated, leading to pervasive sleep deprivation. Objective: To determine whether a novel intervention, using both light exposure during sleep and cognitive behavioral therapy (CBT), would increase total sleep time in teenagers by enabling them to go to sleep earlier than usual. Design, Setting, and Participants: This double-blind, placebo-controlled, randomized clinical trial, conducted between November 1, 2013, and May 31, 2016, among 102 adolescents enrolled full-time in grades 9 to 12, who expressed difficulty going to bed earlier and waking up early enough, was composed of 2 phases. In phase 1, participants were assigned to receive either 3 weeks of light or sham therapy and were asked to try to go to sleep earlier. In phase 2, participants received 4 brief CBT sessions in addition to a modified light or sham therapy. All analyses were performed on an intent-to-treat basis. Interventions: Light therapy consisted of receiving a 3-millisecond light flash every 20 seconds during the final 3 hours of sleep (phase 1) or final 2 hours of sleep (phase 2). Sham therapy used an identical device, but delivered 1 minute of light pulses (appearing in 20-second intervals, for a total of 3 pulses) per hour during the final 3 hours of sleep (phase 1) or 2 hours of sleep (phase 2). Light therapy occurred every night during the 4-week intervention. Cognitive behavioral therapy consisted of four 50-minute in-person sessions once per week. Main Outcomes and Measures: Primary outcome measures included diary-based sleep times, momentary ratings of evening sleepiness, and subjective measures of sleepiness and sleep quality. Results: Among the 102 participants (54 female [52.9%]; mean [SD] age, 15.6 [1.1] years), 72 were enrolled in phase 1 and 30 were enrolled in phase 2. Mixed-effects models revealed that light therapy alone was inadequate in changing the timing of sleep. However, compared with sham therapy plus CBT alone, light therapy plus CBT significantly moved sleep onset a mean (SD) of 50.1 (27.5) minutes earlier and increased nightly total sleep time by a mean (SD) of 43.3 (35.0) minutes. Light therapy plus CBT also resulted in a 7-fold greater increase in bedtime compliance than that observed among participants receiving sham plus CBT (mean [SD], 2.21 [3.91] vs 0.29 [0.76]), as well as a mean 0.55-point increase in subjective evening sleepiness as compared with a mean 0.48-point decrease in participants receiving sham plus CBT as measured on a 7-point sleepiness scale. Conclusions and Relevance: This study found that light exposure during sleep, in combination with a brief, motivation-focused CBT intervention, was able to consistently move bedtimes earlier and increase total sleep time in teenagers. This type of passive light intervention in teenagers may lead to novel therapeutic applications. Trial Registration: ClinicalTrials.gov identifier: NCT01406691.  
  Address (down) Stanford Center for Sleep Sciences and Medicine, Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, California  
  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 2574-3805 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:31553469 Approved no  
  Call Number GFZ @ kyba @ Serial 2683  
Permanent link to this record
 

 
Author Farghly, M.F.; Mahrose, K.M.; Ahmad, E.A.M.; Rehman, Z.U.; Yu, S. url  doi
openurl 
  Title Implementation of different feeding regimes and flashing light in broiler chicks Type Journal Article
  Year 2019 Publication Poultry Science Abbreviated Journal Poult Sci  
  Volume in press Issue Pages  
  Keywords Animals  
  Abstract A 3 x 2 factorial arrangement was implemented to determine the performance of 450 Cobb broilers subjected to different feeding regimes with and without lighting programs. The chicks were divided into 3 groups according to the feeding regime (ad libitum, restricted, or intermittent), and each group was reared under one of two lighting programs (100% continuous light or 50% continuous light and 50% flashing light). The results showed that the broilers under the ad libitum and intermittent feeding regimes had superior body weight (BW) and average daily gain (ADG) values and the lowest feed conversion ratio (FCR) at 3 and 6 wk of age. Broilers exposed to flashing light and an intermittent feeding regime had the highest BW and ADG values and the lowest FCR. Birds exposed to intermittent feeding had the highest dressed carcass weight and the lowest heart weight. Broilers reared with flashing light had higher tenderness and juiciness values than the other groups. Broilers subjected to a restricted feeding regime and flashing light had the lowest abdominal fat values of all the groups. Tenderness and juiciness were significantly higher in broilers subjected to the ad libitum feeding regime x flashing light and the intermittent feeding regime x flashing light. Broilers fed an intermittent regime had the lowest spleen %, heterophil, heterophil to lymphocyte (H/L) ratio and body temperature values of all the groups, and broilers reared under the intermittent regime x flashing light had the lowest spleen %, H/L ratio and body temperature values. Non-significant differences in all health aspects (shank length, keel bone length, foot pad burns, breast blisters score, hock discoloration, and mortality) were observed among the experimental groups. In conclusion, intermittent and restricted feeding regimes and a flashing lighting program improved the FCR and did not produce any adverse effects on performance or physiological parameters. The results of this work show that intermittent feeding and flashing lighting programs are more beneficial to broiler management.  
  Address (down) Shanghai Veterinary Research Institute (SHVRI), Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China  
  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 0032-5791 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30615175 Approved no  
  Call Number GFZ @ kyba @ Serial 2158  
Permanent link to this record
 

 
Author Gonzalez, M.M.C. url  doi
openurl 
  Title Dim Light at Night and Constant Darkness: Two Frequently Used Lighting Conditions That Jeopardize the Health and Well-being of Laboratory Rodents Type Journal Article
  Year 2018 Publication Frontiers in Neurology Abbreviated Journal Front Neurol  
  Volume 9 Issue Pages 609  
  Keywords Animals; Review  
  Abstract The influence of light on mammalian physiology and behavior is due to the entrainment of circadian rhythms complemented with a direct modulation of light that would be unlikely an outcome of circadian system. In mammals, physiological and behavioral circadian rhythms are regulated by the suprachiasmatic nucleus (SCN) of the hypothalamus. This central control allows organisms to predict and anticipate environmental change, as well as to coordinate different rhythmic modalities within an individual. In adult mammals, direct retinal projections to the SCN are responsible for resetting and synchronizing physiological and behavioral rhythms to the light-dark (LD) cycle. Apart from its circadian effects, light also has direct effects on certain biological functions in such a way that the participation of the SCN would not be fundamental for this network. The objective of this review is to increase awareness, within the scientific community and commercial providers, of the fact that laboratory rodents can experience a number of adverse health and welfare outcomes attributed to commonly-used lighting conditions in animal facilities during routine husbandry and scientific procedures, widely considered as “environmentally friendly.” There is increasing evidence that exposure to dim light at night, as well as chronic constant darkness, challenges mammalian physiology and behavior resulting in disrupted circadian rhythms, neural death, a depressive-behavioral phenotype, cognitive impairment, and the deregulation of metabolic, physiological, and synaptic plasticity in both the short and long terms. The normal development and good health of laboratory rodents requires cyclical light entrainment, adapted to the solar cycle of day and night, with null light at night and safe illuminating qualities during the day. We therefore recommend increased awareness of the limited information available with regards to lighting conditions, and therefore that lighting protocols must be taken into consideration when designing experiments and duly highlighted in scientific papers. This practice will help to ensure the welfare of laboratory animals and increase the likelihood of producing reliable and reproducible results.  
  Address (down) Seccion Cronobiologia y Sueno, Instituto Ferrero de Neurologia y Sueno, Buenos Aires, Argentina  
  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 1664-2295 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30116218; PMCID:PMC6084421 Approved no  
  Call Number NC @ ehyde3 @ Serial 2084  
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