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Delineation of physical factors that contribute to earthquake triggering is a challenging issue in seismology. We analyze hydrological modulation of seismicity in Taiwan using groundwater level data and GNSS time series. In western Taiwan, the seismicity rate reaches peak levels in February to April and drops to its lowest values in July to September, exhibiting a direct correlation with annual water unloading. The elastic hydrological load cycle may be the primary driving mechanism for the observed synchronized modulation of earthquakes, as also evidenced by deep earthquakes in eastern Taiwan. However, shallow earthquakes in eastern Taiwan (

We analyze nearest‐neighbor proximities of earthquakes in California based on the joint distribution (T, R) of rescaled time T and rescaled distance R between pairs of earthquakes (Zaliapin & Ben‐Zion, 2013a, https://doi.org/10.1002/jgrb.50179), using seismic catalogs from several regions and several catalogs for the San Jacinto Fault Zone (SJFZ). The study aims to identify informative modes in nearest‐neighbor diagrams beyond the general background and clustered modes, and to assess seismic catalogs derived by different methods. The results show that earthquake clusters with large and small‐to‐medium mainshocks have approximately diagonal and horizontal (T, R) distributions of the clustered mode, respectively, reflecting different triggering distances of mainshocks. Earthquakes in the creeping section of San Andreas Fault have a distinct "repeaters mode" characterized by very large rescaled times T and very small rescaled distances R, due to nearly identical locations of repeating events. Induced seismicity in the Geysers and Coso geothermal fields follow mostly the background mode, but with larger rescaled times T and smaller rescaled distances R compared to tectonic background seismicity. We also document differences in (T, R) distributions of catalogs constructed by different techniques (analyst‐picks, template‐matching and deep‐learning) for the SJFZ, and detect a mode with very large R and small T in the template‐matching and deep‐learning based catalogs. This mode may reflect dynamic triggering by passing waves and/or catalog artifacts. Plain Language Summary: Earthquake patterns in space and time provide important information about the properties of active faults, the surrounding crust, and different loading mechanisms. Nearest‐neighbor diagrams of earthquake proximities in a combined space‐time‐magnitude domain can be used to detect different types of seismicity patterns. Using such diagrams to analyze several earthquake catalogs in California, we examine characteristics of different sections of the San Andreas and San Jacinto faults along with geothermal areas and the entire southern California. The results highlight features of seismicity beyond the well‐known background and clustered modes of earthquakes, including a mode of repeating events in the creeping section of the San Andreas fault and differences between events in regular tectonic areas and geothermal fields. Analyses of different catalogs for the region around the San Jacinto fault also reveal differences related to the different techniques used to construct the catalogs. The results show that nearest‐neighbor diagrams can provide a simple and efficient way to identify different types of seismicity and assess the quality of earthquake catalogs. Key Points: Nearest‐neighbor diagrams provide an efficient way to identify different types of earthquake patternsRepeating events, large versus small‐moderate mainshocks, and induced seismicity have characteristic signaturesNearest‐neighbor diagrams help to evaluate features in catalogs constructed by different methods [ABSTRACT FROM AUTHOR]

The 2013 Ruisui earthquake represents the first unequivocal evidence of the activity of the Central Range fault (CRF) in central Longitudinal Valley, Taiwan. Using a joint Bayesian finite‐fault source inversion of Global Navigation Satellite System and strain time series, we infer that coseismic rupture occurred between 4 and 19 km depth with maximum slip of 0.5 m located near the hypocenter. We then apply a variational Bayesian independent component analysis approach to displacement signals to infer a 3‐months long afterslip located in the near‐source region. This observation represents the first evidence of aseismic slip on the CRF. Combining geodetic and seismological analysis with simulations based on rate‐and‐state friction mechanics, we analyze the interplay between seismic and aseismic deformation during the earthquake sequence. We observe that afterslip is the dominant postseismic deformation mechanism, with >95% of the moment being released aseismically in the postseismic phase and also likely represents the driving force controlling aftershock productivity. Finally, we infer the presence of a shallow velocity strengthening zone (∼0–4 km depth) associated with spatially heterogeneous slip during the postseismic phase with maximum slip of 0.18 m located above the zone of maximum coseismic deformation. Plain Language Summary: Tectonic faults display a broad range of slip patterns, ranging from fast slip (earthquakes) to episodic or continuous aseismic slip. Aseismic transient slip events are now widely observed in active regions and play an important role in stress redistribution in the Earth's crust. The Central Range fault (CRF) is the second most active fault in the Longitudinal Valley, in eastern Taiwan. During the past 15 years, the fault hosted large to destructive earthquakes, but little is known about the presence and the role of aseismic events on the fault deformation. The 2013 Ruisui earthquake reveals for the first time the presence of transient slip regions on the CRF, capable of sustaining aseismic deformation over months. Besides, slow stress relaxation on the fault plane may have also influenced the behavior of seismicity following the mainshock. Monitoring and characterizing the sources of aseismic slip is fundamental to identify areas with high seismic hazard on the fault and to gain more knowledge about the interactions between seismic and aseismic processes. Key Points: We present the first evidence for the detection of postseismic deformation on the Central Range fault, in the Longitudinal Valley (Taiwan)Afterslip represents the dominant deformation mechanism during the postseismic phase and controlled aftershock productionThe velocity strengthening region may have acted like a barrier, resisting the rupture propagation toward the surface during the earthquake [ABSTRACT FROM AUTHOR]

This article examines the case of Taiwan's anti-same-sex marriage referendum of 2018. This case shows that a referendum can severely affect the model of constitutional sovereignty which has guided Taiwan since its democratisation. The fact that populists were able to use the referendum as a tool to delegitimise the state organs, we argue, throws light on the relationship between populism and direct democracy. [ABSTRACT FROM AUTHOR]

In the present study, the hepatoprotective action of Limonium sinense (Plumbaginaceae) was evident after carbon tetrachloride (CCl(4)) and beta-D-galactosamine (D-GalN), respectively, challenge in rats. The plant materials were divided into two parts: (1) the roots extracted with water (WRE) and (2) the leaves extracted with methanol and fractionated with chloroform (CLE). Both WRE and CLE were extremely flavonoid-enriched extracts. In an CCl(4)-induced acute liver damage study, pretreatment with WRE at 300 mg/kg i.p. and CLE at 100 mg/kg i.p. significantly reduced the amino-transaminases levels of SGOT (p < 0.01) and SGPT (p < 0.01) previously increased by CCl(4) intoxication. In D-GalN-induced acute liver damage study, administration of WRE (300 and 500 mg/kg) or CLE (100 mg/kg) p.o. also significantly reduced the SGOT (p < 0.01) and SGPT (p < 0.01) levels previously increased by D-GalN intoxication. Furthermore, the serum triglyceride level was increased after pretreatment with WRE or CLE previously reduced by D-GalN intoxication. All of the liver function profiles were confirmed to have improvement of liver lesion in histopathological observation. In an acute toxicity test on ICR mice, the LD(50) of WRE was 777.6 mg/kg i.p. An in vitro study showed that CLE possessed a more potent cytotoxicity to human hepatocellular carcinoma cells (Hep3B) (EC(50) = 43.1 micro g/mL) than the other organic fractions, which were fractionated from methanol extracts of the leaves of L. sinense. The present results conclude that L. sinense possesses a hepatoprotective efficacy, and is relatively safe in rats., (Copyright 2003 John Wiley & Sons, Ltd.)