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Monitoring slow earthquake activity in subduction zones can give important insight into the stress build-up and subsequent rupture extent of megathrust earthquakes. Extensive slow earthquake activi...

On the western part of the Pacific Plate most seamounts formed during the Cretaceous period in the so‐called West Pacific Seamount Province (WPSP). On the northwestern part of the same plate, the Joban and Japanese Seamount Trail (JJST) are also composed of Early Cretaceous seamounts. However, two new groups of knolls were recently discovered during multibeam surveys on the Pacific Plate along the Japan Trench. One group consists of circular knolls that are flat‐topped in shape and correspond to eruptive ages of approximately 75 Ma. The other group consists of irregularly shaped knolls, also called petit‐spot volcanoes, that are found on the outer‐rise systems of the subducting Pacific Plate. These petit‐spots seem much younger and available age data suggest that they only formed in the last few million years. Acoustic reflective data, which are simultaneously obtained with bathymetrical data, are a most powerful tool to distinguish the petit‐spots from the Cretaceous edifices in the WPSP and JJST. In this paper, we present the results of an exploratory search for these new kind of petit‐spot volcanoes along the trenches in the Pacific Ocean, with an emphasis on the Japan and Tonga trenches. The sizes of these irregularly shaped petit‐spot volcanoes are several orders of magnitude less than the Cretaceous seamounts and circular knolls, yet they appear to be ubiquitous on the ocean floor, in particular, where incipient melts in the asthenosphere can be squeezed out by tectonic forces.

Cancer gene therapy and oncolytic virotherapy have been studied extensively. However, their clinical application is hampered by their weak anticancer activity. We previously constructed a replicating adenovirus (OBP-301, Telomelysin), in which the human telomerase reverse transcriptase (hTERT) promoter drives expression of the adenoviral E1 genes, and causes selective lysis of human cancer cells. We hypothesized that combination adenoviral therapy containing OBP-301 and a nonreplicating adenovirus expressing the proapoptotic Bax gene could overcome the weakness and augment the anticancer efficacy of each modality. Combination treatment resulted in marked Bax protein expression and enhanced efficacy in in vitro cell viability assay, when compared with either single treatment. However, combination treatment was not as effective in suppressing both subcutaneous and pleural disseminated tumors compared with OBP-301 treatment alone. Further investigation revealed that combination treatment resulted in suppressed E1A protein expression associated with reduced viral replication. Our results suggest that Bax gene therapy in combination with oncolytic adenovirotherapy potentially augments their antitumor activity, but further improvements may be required to maximize the combinatorial effect in vivo, for the Bax gene expression to avoid interference with production of the oncolytic virus. © 2008 Wiley-Liss, Inc.