We present historical and geomorphological evidence of a regularity in earthquake recurrence at three different sites of plate convergence around the Japan arcs. The regularity shows that the larger an earthquake is, the longer is the following quiet period. In other words, the time interval between two successive large earthquakes is approximately proportional to the amount of coseismic displacement of the preceding earthquake and not of the following earthquake. The regularity enables us, in principle, to predict the approximate occurrence time of earthquakes. The data set includes 1) a historical document describing repeated measurements of water depth at Murotsu near the focal region of Nankaido earthquakes, 2) precise levelling and 14C dating of Holocene uplifted terraces in the southern Boso peninsula facing the Sagami trough, and 3) similar geomorphological data on exposed Holocene coral reefs in Kikai Island along the Ryukyu arc.

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The ∼2500 km long Himalayan arc has experienced three large to great earthquakes of Mw 7.8 to 8.4 during the past century, but none produced surface rupture. Paleoseismic studies have been conducted during the last decade to begin understanding the timing, size, rupture extent, return period, and mechanics of the faulting associated with the occurrence of large surface rupturing earthquakes along the ∼2500 km long Himalayan Frontal Thrust (HFT) system of India and Nepal. The previous studies have been limited to about nine sites along the western two‐thirds of the HFT extending through northwest India and along the southern border of Nepal. We present here the results of paleoseismic investigations at three additional sites further to the northeast along the HFT within the Indian states of West Bengal and Assam. The three sites reside between the meizoseismal areas of the 1934 Bihar‐Nepal and 1950 Assam earthquakes. The two westernmost of the sites, near the village of Chalsa and near the Nameri Tiger Preserve, show that offsets during the last surface rupture event were at minimum of about 14 m and 12 m, respectively. Limits on the ages of surface rupture at Chalsa (site A) and Nameri (site B), though broad, allow the possibility that the two sites record the same great historical rupture reported in Nepal around A.D. 1100. The correlation between the two sites is supported by the observation that the large displacements as recorded at Chalsa and Nameri would most likely be associated with rupture lengths of hundreds of kilometers or more and are on the same order as reported for a surface rupture earthquake reported in Nepal around A.D. 1100. Assuming the offsets observed at Chalsa and Nameri occurred synchronously with reported offsets in Nepal, the rupture length of the event would approach 700 to 800 km. The easternmost site is located within Harmutty Tea Estate (site C) at the edges of the 1950 Assam earthquake meizoseismal area. Here the most recent event offset is relatively much smaller (<2.5 m), and radiocarbon dating shows it to have occurred after A.D. 1100 (after about A.D. 1270). The location of the site near the edge of the meizoseismal region of the 1950 Assam earthquake and the relatively lesser offset allows speculation that the displacement records the 1950 Mw 8.4 Assam earthquake. Scatter in radiocarbon ages on detrital charcoal has not resulted in a firm bracket on the timing of events observed in the trenches. Nonetheless, the observations collected here, when taken together, suggest that the largest of thrust earthquakes along the Himalayan arc have rupture lengths and displacements of similar scale to the largest that have occurred historically along the world's subduction zones.

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To provide a detailed record of a relatively rare thrust surface rupture and examine its active tectonic implications, we have conducted field mapping of the surface rupture associated with the 2005 M w 7.6 Kashmir earthquake. Despite the difficulty arising from massive earthquake-induced landslides along the surface rupture, we found that typical pressure ridges and warps extend northwestward for a distance of ∼70 km, with a northeast-side-up vertical separation of up to ∼7 m. Neither the main frontal thrust nor the main boundary thrust is responsible for the earthquake, but three active faults or fault segments within the Sub-Himalaya, collectively called the Balakot-Bagh fault, compose the causative fault. Although the fault exhibits substantial geomorphic expression of repeated similar surface ruptures, only a part of it had been mapped as active before the earthquake. The location of the hypocenter suggests that the rupture was initiated at a deep portion of the northern-central segment boundary and propagated bilaterally to eventually break all three segments. Our obtained surface rupture traces and the along-strike-slip distribution are both in good agreement with results of prompt analyses of satellite images, indicating that space geodesy can greatly aid in time-consuming field mapping of surface ruptures. Assuming that the extensive fill terrace in the meizoseismal area was abandoned during 10-30 ka, we tentatively estimate the earthquake recurrence interval and shortening rate on the Balakot-Bagh fault to be 1000-3300 yr and 1:4-4:1 mm=yr, respectively. These estimates indicate that the Balakot-Bagh fault is not a main player of Himalayan contraction accommodation. Ⓔ Selected field photographs and ArcGIS files of the mapped surface rupture traces and measured vertical separations are available in the electronic edition of BSSA.Online Material: Field photographs and ArcGIS files of surface rupture traces and vertical separations.

Signaling through extracellular signal-regulated kinase (ERK) is important in multiple signal transduction networks in the CNS. However, the specific role of ERK2 in in vivo brain functions is not fully understood. Here we show that ERK2 play a critical role in regulating social behaviors as well as cognitive and emotional behaviors in mice. To study the brain function of ERK2, we used a conditional, region-specific, genetic approach to target Erk2 using the Cre/loxP strategy with a nestin promoter-driven cre transgenic mouse line to induce recombination in the CNS. The resulting Erk2 conditional knock-out (CKO) mice, in which Erk2 was abrogated specifically in the CNS, were viable and fertile with a normal appearance. These mice, however, exhibited marked anomalies in multiple aspects of social behaviors related to facets of autism-spectrum disorders: elevated aggressive behaviors, deficits in maternal nurturing, poor nestbuilding, and lower levels of social familiarity and social interaction. Erk2 CKO mice also exhibited decreased anxiety-related behaviors and impaired long-term memory. Pharmacological inhibition of ERK1 phosphorylation in Erk2 CKO mice did not affect the impairments in social behaviors and learning disabilities, indicating that ERK2, but not ERK1 plays a critical role in these behaviors. Our findings suggest that ERK2 has complex and multiple roles in the CNS, with important implications for human psychiatric disorders characterized by deficits in social behaviors.

Although LN metastasis is a significant prognostic factor, the most obvious recurrence pattern after surgery was intrahepatic recurrence, which could be predicted preoperatively by a combination of elevated serum CA19-9 levels and manifestation of obstructive jaundice.

Amino acid transport system L has been proposed to be one of the major nutrient transport systems at the blood-brain barrier. Using immunohistochemical analyses, a system L transporter LAT1 was shown to be expressed in the brain capillary endothelial cells in rats. Because LAT1 was coexpressed with 4F2 heavy chain which brings LAT1 to the plasma membrane, LAT1 is proposed to be functional in the plasma membrane of brain capillary endothelial cells. Both LAT1 and 4F2hc immunoreactivities were detected in a double line appearance surrounding endothelial cell nuclei, suggesting both proteins are present in the luminal and abluminal membranes. LAT1 is, thus, a blood-brain barrier system L transporter responsible for the permeation of aromatic or branched-chain amino acids and amino acid-related drugs such as L-DOPA.