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Author Konkal, P.; Ganesh, C.B.
Title Exposure to low or high light intensity affects pituitary-testicular activity in the fish Oreochromis mossambicus Type Journal Article
Year 2018 Publication Aquaculture Abbreviated Journal Aquaculture
Volume 497 Issue Pages 109-116
Keywords Animals
Abstract Light is an important factor for the successful reproduction of most fish. In this investigation, effect of different light intensities on pituitary-testis axis was studied for a period of 21 days, under normal photoperiodic regime in the tilapia Oreochromis mossambicus. The mean numbers of spermatogonia (Sg), primary spermatocytes (Ps), secondary spermatocytes (Ss), early spermatids (Est) and late spermatids (Lst) did not show significant difference between fish exposed to moderate light intensity (MLI) and initial controls or controls, whereas the mean numbers of Sg were significantly lower in fish exposed to low light intensity (LLI) compared to those of initial controls, controls and MLI groups. However, the mean numbers of Ps, Ss, Est and Lst were significantly lower in fish exposed to LLI and high light intensity (HLI) compared to those of other experimental groups. Furthermore, in the pituitary gland, weakly immunoreactive luteinizing hormone (LH) secreting cells were observed in the proximal pars distalis (PPD) region in fish exposed to LLI and HLI in contrast to the intense immunolabelling of these cells in initial controls, controls and MLI groups. The androgen receptors showed diminished immunoreactivity in the Sertoli cells along the seminiferous lobules of the testis in fish exposed to LLI and HLI, whereas the strongly immunoreactive androgen receptors were observed in the Sertoli cells in initial controls, controls and MLI groups. Taken together, these results indicate that long-term exposure to low or high light intensity light suppresses spermatogenetic process and that this inhibition is due to reduced secretory activity of LH cells in the pituitary gland and androgen secretion in the testis of the fish O. mossambicus.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0044-8486 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 1974
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Author Zhou, Y.; Li, X.; Asrar, G.R.; Smith, S.J.; Imhoff, M.
Title A global record of annual urban dynamics (1992–2013) from nighttime lights Type Journal Article
Year 2018 Publication Remote Sensing of Environment Abbreviated Journal Remote Sensing of Environment
Volume 219 Issue Pages 206-220
Keywords Remote Sensing
Abstract The nighttime light (NTL) observations from Defense Meteorological Satellite Program/Operational Linescane System (DMSP/OLS) offer great potentials to study urban dynamics from regional to global scales, for more than two decades. In this paper, we presented a new approach to develop spatially and temporally consistent global urban maps from 1992 to 2013, using the DMSP/OLS NTL observations. First, potential urban clusters were delineated using the NTL data and a segmentation method. Then, a quantile-based approach was used to remove rural and suburban areas sequentially in the potential urban clusters. Finally, the derived series of urban extents in the entire study period (1992–2013) were improved for temporal consistency. We found the percentage of global urban areas relative to the world's land surface area increased from 0.23% in 1992 to 0.53% in 2013. Asia is the continent with the most significant urban growth, worldwide. The time series of global urban maps were evaluated for the spatial agreement and temporal consistency using a variety of widely used independent land-cover products. This evaluation indicates that the proposed approach is robust and performs well in deriving global urban dynamics across different spatial scales, i.e., cluster, province (or state), country, and region. Moreover, this quantile-based approach is advantageous, compared with other methods used in previous studies, because it does not require additional data for enhancement or calibration. The new time series of urban maps from this study offer a new dataset for studying global urbanization during the past decades and unique information to explore potential future trajectories of urban development, which appears to be distinct for different nations/regions, globally. Such information is pre-requisite for achieving the sustainable development goals, and associated targets, during ensuing decades.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0034-4257 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2048
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Author Zheng, Q.; Weng, Q.; Huang, L.; Wang, K.; Deng, J.; Jiang, R.; Ye, Z.; Gan, M.
Title A new source of multi-spectral high spatial resolution night-time light imagery—JL1-3B Type Journal Article
Year 2018 Publication Remote Sensing of Environment Abbreviated Journal Remote Sensing of Environment
Volume 215 Issue Pages 300-312
Keywords Remote Sensing
Abstract Artificial light at night (ALAN) provides a unique footprint of human activities and settlements. However, the adverse effects of ALAN on human health and ecosystems have not been well understood. Because of a lack of high resolution data, studies of ALAN in China have been confined to coarse resolution, and fine-scale details are missing. The fine details of ALAN are pertinent, because the highly dense population in Chinese cities has created a distinctive urban lighting pattern. In this paper, we introduced a new generation of high spatial resolution and multi-spectral night-time light imagery from the satellite JL1-3B. We examined its effectiveness for monitoring the spatial pattern and discriminating the types of artificial light based on a case study of Hangzhou, China. Specifically, local Moran's I analysis was applied to identify artificial light hotspots. Then, we analyzed the relationship between artificial light brightness and land uses at the parcel-level, which were generated from GF-2 imagery and open social datasets. Third, a machine learning based method was proposed to discriminate the type of lighting sources – between high pressure sodium lamps (HPS) and light-emitting diode lamps (LED) – by incorporating their spectral information and morphology feature. The result shows a complicated heterogeneity of illumination characteristics across different land uses, where main roads, commercial and institutional areas were brightly lit while residential area, industrial area and agricultural land were dark at night. It further shows that the proposed method was effective at separating light emitted by HPS and LED, with an overall accuracy and kappa coefficient of 83.86% and 0.67, respectively. This study demonstrates the effectiveness of JL1-3B and its superiority over previous night-time light data in detecting details of lighting objects and the nightscape pattern, and suggests that JL1-3B and alike could open up new opportunities for the advancement of night-time remote sensing.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0034-4257 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 1945
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Author Wang, L.; Wang, S.; Zhou, Y.; Liu, W.; Hou, Y.; Zhu, J.; Wang, F.
Title Mapping population density in China between 1990 and 2010 using remote sensing Type Journal Article
Year 2018 Publication Remote Sensing of Environment Abbreviated Journal Remote Sensing of Environment
Volume 210 Issue Pages 269-281
Keywords Remote Sensing
Abstract Knowledge of the spatial distribution of populations at finer spatial scales is of significant value and fundamental to many applications such as environmental change, urbanization, regional planning, public health, and disaster management. However, detailed assessment of the population distribution data of countries that have large populations (such as China) and significant variation in distribution requires improved data processing methods and spatialization models. This paper described the construction of a novel population spatialization method by combining land use/cover data and night-light data. Based on the analysis of data characteristics, the method used partial correlation analysis and geographically weighted regression to improve the distribution accuracy and reduce regional errors. China's census data for the years 1990, 2000, and 2010 were assessed. The results showed that the method was better at population spatialization than methods that use only night-light data or land use/cover data and global linear regression. Evaluation of overall accuracies revealed that the coefficient of correlation R-square was >0.90 and increased by >0.13 in the years 1990, 2000, and 2010. Moreover, the local R-square of over 90% of the samples (counties) was higher than the adjusted R-square of the general linear regression model. Furthermore, the gridded population density datasets obtained by this method can be used to analyse spatial-temporal patterns of population density and provide population distribution information with increased accuracy and precision compared to conventional models.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0034-4257 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2480
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Author Netzel, H.; Netzel, P.
Title High-resolution map of light pollution Type Journal Article
Year 2018 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer
Volume 221 Issue Pages 300-308
Keywords Skyglow
Abstract In 1976 Berry created a very simple model describing artificial night sky brightness due to light emitted by cities. He used several assumptions and simplifications, due to which, map calculated with this model does not properly describes the night sky brightness. Especially, this is the case for highly urbanized areas. We used Berry’s idea, but we changed some assumptions and used very different input data. As in Berry’s approach, we focused on total sky brightness and did not analyze spectral properties of artificial light emission. Resultant map has a resolution of 100 meters, and so far it is the most detailed map of night sky brightness. Moreover we included the shadowing effect, which is very important on mountainous areas. Map is calculated for Poland and for several other places in Europe. We also describe the comparison between calculated values and measurements for different areas in Europe. Also we present comparison between our approach and the new world atlas of artificial night sky brightness.
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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 0022-4073 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 1937
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