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Electromagnetic Precursors to the 2016 Kumamoto Earthquakes
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作者 Alexander Schekotov Jun Izutsu +2 位作者 Tomokazu Asano Stelios Marcos Potirakis Masashi Hayakawa 《Open Journal of Earthquake Research》 2017年第4期168-179,共12页
The Kumamoto area of Kyusyu Island was attacked by a series of large earthquakes (EQs) in April, 2016. The first two foreshocks had the magnitudes of 6.5 and 6.4, and about 1 day later there was the main shock on 15 A... The Kumamoto area of Kyusyu Island was attacked by a series of large earthquakes (EQs) in April, 2016. The first two foreshocks had the magnitudes of 6.5 and 6.4, and about 1 day later there was the main shock on 15 April (UT) with magnitude 7.3. These are fault-type EQs, and so we would expect a variety of electromagnetic precursors to these EQs because we had detected different phenomena for the 1995 Kobe EQ, same fault-type EQ. As for the lithospheric effect, the ULF data at Kanoya observatory (about 150 km from the EQ epicenters) are used, but the simple statistical analysis could not provide us with any clear evidence of ULF radiation from the lithosphere. However, our conventional analyses indicated clear signatures in the atmosphere as ULF/ELF impulsive emissions and also in the ionosphere as observed by means of VLF propagation anomalies and ULF depression. ULF/ELF radiation appeared on 8-11 April (in UT) (maximum on 10 and 11 April (UT)), while ULF depression took place on 8 and 10 April (in UT), so that both atmospheric radiation and ionospheric perturbation took place nearly during the same time period. 展开更多
关键词 ELECTROMAGNETIC Precursors The 2016 Kumamoto EARTHQUAKES ULF/ELF Radiation VLF Propagation ANOMALY ULF Depression
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New Material of the Zalambdalestid Zhangolestes(Mammalia,Zalambdalestidae)from the Late Cretaceous Changchunsaurus Fauna of Jilin,China 被引量:1
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作者 CHEN Jun MAO Fangyuan +1 位作者 WU Wenhao MENG Jin 《Acta Geologica Sinica(English Edition)》 2025年第3期634-645,共12页
We report new material of the zalambdalestid,Zhangolestes jilinensis,from the Quantou Formation(lower Upper Cretaceous,Cenomanian to Turonian),Gongzhuling City,Jilin Province,NE China.Using micro-CT-scan,the material ... We report new material of the zalambdalestid,Zhangolestes jilinensis,from the Quantou Formation(lower Upper Cretaceous,Cenomanian to Turonian),Gongzhuling City,Jilin Province,NE China.Using micro-CT-scan,the material is shown to include dentocranial and postcranial elements recovered from the same matrix block containing the holotype specimen.The CT-images also show the labial and internal structures of the holotype fragment of the lower jaw of Z.jilinensis.Based on the preservation,relative size,and tooth wear,the new material and the holotype lower jaw likely belong to the same individual animal,whereas the hypodigm mandibular fragment assigned to Z.jilinensis in the original study is thought now to belong to a different individual,potentially representing a different species,which,if true,would increase the eutherian diversity in the Late Cretaceous Changchunsaurus Fauna.Furthermore,the new CT-images show that the incisor morphology is diverse within zalambdalestids and probably evolved independently from the enlarged incisors in placental mammals,such as Glires. 展开更多
关键词 vertebrate paleontology morphology Zalambdalestidae Quantou Formation CENOMANIAN-TURONIAN Jilin Province
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Application of PROTAC strategy to TTR-Aβ protein-protein interaction for the development of Alzheimer's disease drugs 被引量:3
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作者 NicolóTonali Susanna Nencetti +1 位作者 Elisabetta Orlandini Lidia Ciccone 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第8期1554-1555,共2页
Alzheimer's disease(AD) is a complex and multifaced neurodegenerative disorder for which the precise pathological molecular mechanisms are still not completely known. In last years, rational multi-target drug desi... Alzheimer's disease(AD) is a complex and multifaced neurodegenerative disorder for which the precise pathological molecular mechanisms are still not completely known. In last years, rational multi-target drug design methods, which combine multiple molecules having complementary modes of action, have been increasingly used in the development of anti-AD drugs. 展开更多
关键词 DRUGS ALZHEIMER
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Characterization of peach tree crown by using high-resolution images from an unmanned aerial vehicle 被引量:13
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作者 Yue Mu Yuichiro Fujii +5 位作者 Daisuke Takata Bangyou Zheng Koji Noshita Kiyoshi Honda Seishi Ninomiya Wei Guo 《Horticulture Research》 SCIE 2018年第1期22-31,共10页
In orchards, measuring crown characteristics is essential for monitoring the dynamics of tree growth and optimizing farm management. However, it lacks a rapid and reliable method of extracting the features of trees wi... In orchards, measuring crown characteristics is essential for monitoring the dynamics of tree growth and optimizing farm management. However, it lacks a rapid and reliable method of extracting the features of trees with an irregular crown shape such as trained peach trees. Here, we propose an efficient method of segmenting the individual trees and measuring the crown width and crown projection area (CPA) of peach trees with time-series information, based on gathered images. The images of peach trees were collected by unmanned aerial vehicles in an orchard in Okayama, Japan, and then the digital surface model was generated by using a Structure from Motion (SfM) and Multi-View Stereo (MVS) based software. After individual trees were identified through the use of an adaptive threshold and marker-controlled watershed segmentation in the digital surface model, the crown widths and CPA were calculated, and the accuracy was evaluated against manual delineation and field measurement, respectively. Taking manual delineation of 12 trees as reference, the root-mean-square errors of the proposed method were 0.08 m (R^(2) = 0.99) and 0.15 m (R^(2) = 0.93) for the two orthogonal crown widths, and 3.87 m2 for CPA (R^(2) = 0.89), while those taking field measurement of 44 trees as reference were 0.47 m (R^(2) = 0.91), 0.51 m (R^(2) = 0.74), and 4.96 m2 (R^(2) = 0.88). The change of growth rate of CPA showed that the peach trees grew faster from May to July than from July to September, with a wide variation in relative growth rates among trees. Not only can this method save labour by replacing field measurement, but also it can allow farmers to monitor the growth of orchard trees dynamically. 展开更多
关键词 CROWN TREE WATERSHED
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Modeling the impacts of climate variability and hurricane on carbon sequestration in a coastal forested wetland in South Carolina
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作者 Zhaohua Dai Carl C. Trettin +3 位作者 Changsheng Li Ge Sun Devendra M. Amatya Harbin Li 《Natural Science》 2013年第3期375-388,共14页
The impacts of hurricane disturbance and climate variability on carbon dynamics in a coastal forested wetland in South Carolina of USA were simulated using the Forest-DNDC model with a spatially explicit approach. The... The impacts of hurricane disturbance and climate variability on carbon dynamics in a coastal forested wetland in South Carolina of USA were simulated using the Forest-DNDC model with a spatially explicit approach. The model was validated using the measured biomass before and after Hurricane Hugo and the biomass inventories in 2006 and 2007, showed that the Forest- DNDC model was applicable for estimating carbon dynamics with hurricane disturbance. The simulated results indicated that Hurricane Hugo in 1989 substantially influenced carbon storage immediately after the disturbance event. The simulated net ecosystem exchange (NEE) for the 58-year period (1950-2007) indicated that the hurricane reduced CO2 sequestration due primarily to the increased decomposition of a large amount of litter and woody debris, including fallen trees (over 80% of pre-hurricane trees), debris and branches, and dead roots. The inter-annual fluctuation of soil CO2 flux showed that the climate variability interfered substantially soil carbon dynamics in the forest. The results showed that there were substantial spatial and temporal differences in CO2 flux (3.2 - 4.8 Mg·C·ha–1) and wood biomass due to the differences in physical and biogeochemical characteristics in the forest. 展开更多
关键词 GREENHOUSE Gas Forest-DNDC BIOGEOCHEMICAL Model Biomass Climate Change
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Assessing the potential landslide risk identification in the northern section of CPEC route Pakistan based on Multi-Temporal InSAR approaches
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作者 Meer Muhammad SAJJAD WANG Juanle +3 位作者 GE Daqing Rehan KHAN Izhar AHMED Khan ZADA 《Journal of Mountain Science》 SCIE CSCD 2024年第12期4131-4148,共18页
Landslides are the most frequent geoenvironmental natural hazards in hilly regions,owing to broken rock masses and slope instability.Every year,landslides occur along the Karakorum highway in the northern section of t... Landslides are the most frequent geoenvironmental natural hazards in hilly regions,owing to broken rock masses and slope instability.Every year,landslides occur along the Karakorum highway in the northern section of the China-Pakistan Economic Corridor,involving complex geological action and causing significant damages and fatalities.To mitigate landslide hazard risks and a better understanding of landslide occurrence in steep mountainous regions,a comprehensive and precise analysis of slow-moving landslides is necessary.To address this challenge,a Multi-Temporal(MT),Interferometry Synthetic Aperture Radar(InSAR)approach using Small Baseline Subsets and Interferometric Point Target Analysis techniques was utilized to extract ground deformation rates.A total of 121 multitrack synthetic aperture radar images from Sentinel-1A were acquired from 2021 to 2023,enabling the detection and monitoring of ground displacement over time.Eight active slope movements were successfully identified by calculating the differences in deformation,indicating a significant deformation rate within the trust fault lines and regional geological formations.The research findings reveal that the regional geological structure,including lithology and fault lines,significantly increase the deformation rate.These identified landslide hazard areas range from 1.47 km2 to 14.88 km2,with an annual average rate of line of sight surface displacement estimated between−4.13 to−16.07 cm/yr.The MT-InSAR analysis demonstrates that fault lines and geology play significant role in surface deformation,providing valuable insights into the deformation induced by regional tectonic activities. 展开更多
关键词 INSAR Deformation LANDSLIDE SBAS IPTA Karakorum highway
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Seismogenic ULF/ELF Wave Phenomena: Recent Advances and Future Perspectives
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作者 Masashi Hayakawa Alexander Schekotov +2 位作者 Jun Izutsu Alexander P. Nickolaenko Yasuhide Hobara 《Open Journal of Earthquake Research》 2023年第3期45-113,共69页
There has been enormous progress in the field of electromagnetic phenomena associated with earthquakes (EQs) and EQ prediction during the last three decades, and it is recently agreed that electromagnetic effects do a... There has been enormous progress in the field of electromagnetic phenomena associated with earthquakes (EQs) and EQ prediction during the last three decades, and it is recently agreed that electromagnetic effects do appear prior to an EQ. A few phenomena are well recognized as being statistically correlated with EQs as promising candidates for short-term EQ predictors: the first is ionospheric perturbation not only in the lower ionosphere as seen by subionospheric VLF (very low frequency, 3 kHz f 30 kHz)/LF (low frequency, 30 kHz f 300 kHz) propagation but also in the upper F region as detected by ionosondes, TEC (total electron content) observations, satellite observations, etc, and the second is DC earth current known as SES (Seismic electric signal). In addition to the above two physical phenomena, this review highlights the following four physical wave phenomena in ULF (ultra low frequency, frequency Hz)/ELF (extremely low frequency, 3 Hz frequency 3 kHz) ranges, including 1) ULF lithospheric radiation (i.e., direct radiation from the lithosphere), 2) ULF magnetic field depression effect (as an indicator of lower ionospheric perturbation), 3) ULF/ELF electromagnetic radiation (radiation in the atmosphere), and 4) Schumann resonance (SR) anomalies (as an indicator of the perturbations in the lower ionosphere and stratosphere). For each physical item, we will repeat the essential points and also discuss recent advances and future perspectives. For the purpose of future real EQ prediction practice, we pay attention to the statistical correlation of each phenomenon with EQs, and its predictability in terms of probability gain. Of course, all of those effects are recommended as plausible candidates for short-term EQ prediction, and they can be physically explained in terms of the unified concept of the lithosphere-atmosphere-ionosphere coupling (LAIC) process, so a brief description of this coupling has been carried out by using these four physical parameters though the mechanism of each phenomenon is still poorly understood. In conclusion, we have to emphasize the importance of more statistical studies for more abundant datasets sometimes with the use of AI (artificial intelligence) techniques, more case studies for huge (M greater than 7) EQ events, recommendation of critical analyses, and finally multi-parameters observation (even though it is tough work). 展开更多
关键词 ULF/ELF Seismogenic Wave Effects Statistical Significance Lithosphere-Atmosphere-Ionosphere Coupling
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Digital Earth:A platform for the SDGs and green transformation at the global and local level,employing essential SDGs variables 被引量:2
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作者 Hiromichi Fukui Duc Chuc Man Anh Phan 《Big Earth Data》 EI 2021年第4期476-496,共21页
The 17 Sustainable Development Goals present clear directions toward the green transformation being sought by the global com-munity.The SDGs are an integrated framework,with a complex network of interlinkages between ... The 17 Sustainable Development Goals present clear directions toward the green transformation being sought by the global com-munity.The SDGs are an integrated framework,with a complex network of interlinkages between the goals,targets and indicators,and they pose wicked problems to society.Consequently,measur-ing progress and achievements with the SDGs requires the integra-tion of various spatio-temporal datasets from different domains and the synthesis of disciplines to describe a system of systems.The Group on Earth Observations has developed the concept of Essential Variables to describe systems across Societal Benefit Areas that are applicable for this purpose.Digital Earth is a virtual representation of the planet,potentially encompassing all its sys-tems and life forms,including human societies.Designed as a multidimensional,multi-scale,multi-temporal,and multi-layer informa-tion facility,Digital Earth is a valuable platform that can contribute to the achievement of the SDGs and a green transformation.To that end,a set of Essential SDGs Variables(ESDGVs)for the platform are proposed and cases of implementation and use are introduced. 展开更多
关键词 Digital Earth SDGs Earth Observation INTEROPERABILITY Essential Variables
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Normalization of VIIRS DNB images for improved estimation of socioeconomic indicators 被引量:2
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作者 Man Duc Chuc Tsubasa Hirakawa Hiromichi Fukuic 《International Journal of Digital Earth》 SCIE 2021年第5期540-554,共15页
Monthly Visible Infrared Imaging Radiometer Suite(VIIRS)Day-Night Band(DNB)composite data are widely used in research,such as estimations of socioeconomic parameters.However,some surface conditions affect the VIIRS DN... Monthly Visible Infrared Imaging Radiometer Suite(VIIRS)Day-Night Band(DNB)composite data are widely used in research,such as estimations of socioeconomic parameters.However,some surface conditions affect the VIIRS DNB radiance,which may create some estimation bias in certain regions.In this paper,we propose a novel normalization algorithm for VIIRS DNB monthly composite data.The aim is to normalize VIIRS radiance,collected under different surface conditions,to a reference point,so that the bias is reduced.The algorithm is based on the utilization of stable lit pixels as a reference and a nonlinear regression algorithm,to match un-normalized data to the reference data.Experimental results show that the algorithm could improve correlation(R2)between the total sum of nightlights(TOL),electric power consumption(EPC),and gross domestic product(GDP)at both a global and local scale.The algorithm could significantly diminish the seasonal component of un-normalized nightlights radiance caused by snow.The intensified nightlights radiance in sandy regions could also be reduced to a more reasonable range in comparison with other regions.Visual inspection shows that the brightness of snow-affected and sandy regions was strongly reduced after undergoing normalization. 展开更多
关键词 VIIRS DNB seasonal factors stable lit NORMALIZATION socioeconomic indicators
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Quantifying the impacts of the COVID-19 pandemic lockdown and the armed conflict with Russia on Sentinel 5P TROPOMI NO_(2)changes in Ukraine
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作者 Anh Phan Hiromichi Fukui 《Big Earth Data》 EI CSCD 2024年第1期58-81,共24页
This study investigated variations in nitrogen dioxide(NO_(2))levels in Ukraine during two significant periods:the COVID-19 pandemic lockdown in 2020 and the armed conflict with Russia in 2022.Original and reprocessed... This study investigated variations in nitrogen dioxide(NO_(2))levels in Ukraine during two significant periods:the COVID-19 pandemic lockdown in 2020 and the armed conflict with Russia in 2022.Original and reprocessed Sentinel 5P data products were utilized for the analysis.A machine learning model was employed to generate a business-as-usual NO_(2)time series that accounted for meteorological variability.For the nine most populous cities in Ukraine,during the lockdown in 2020 we observed a moderation of increases in NO_(2)levels during the lockdown compared to the pre-lockdown levels.Looking at the same months during the conflict period in 2022,we identified much more significant reductions in NO_(2)level in these cities,averaging 12.1%for original and 18.1%for reprocessed datasets.Besides our examination of major urban areas,we observed reductions in NO_(2)levels in areas surrounding coal power plants damaged or destroyed by the conflict.For the major urban areas in Ukraine,we conclude that changes in daily anthropogenic activities due to the conflict-related events had more substantial impacts on NO_(2)levels than did COVID-19 lockdown. 展开更多
关键词 NO_(2) COVID-19 Russia-Ukraine armed conflict weather-normalization
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