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Abstract. The scale factor of a superconducting gravimeter (SG) at the Esashi Earth Tides Station, Japan, was revised by repeating co-located absolute gravity measurements with an FG5 gravimeter. Although the calibration results from the absolute gravimeter (AG) show an apparent secular change in the scale factor of the SG (0.4% for the period 19932002), the relative scale factors, which are determined by tidal analysis with the response method, indicate that it has changed by no more than 0.01% during the above period. If the mean scale factor over the 10 years is adopted, a value of -56.0820.029 Gal/V (1 Gal =10-8 m s-2) is obtained, which is about 0.4% smaller than that used in the global geodynamics project (GGP) database. Based on this newly determined scale factor, the tidal gravity factors at Esashi have been re-estimated. The observed tidal factors, corrected for the ocean tide effects with recent models, indicate that the theoretical gravity factors for an inelastic Earth model are more consistent with the observations than are those for an elastic model. [ABSTRACT FROM AUTHOR]

Fifty-one yeast strains isolated from fermented mash of Balinese rice wine, brem, fermented using five different types of starters, ragi tape, were identified on the basis of their internal transcribed spacer (ITS) regions and their 18S rDNA sequences. The results revealed that Saccharomyces cerevisiae (35 strains), Candida glabrata (six strains), Pichia anomala (three strains) and Issatchenkia orientalis (seven strains) were the main yeasts in the fermentation of the rice wine. These yeasts undergo succession during the fermentation in which S. cerevisiae was mostly found as the principal yeast at the end of fermentation. Phylogenetic analysis based on the 18S rDNA sequences of selected strains placed the isolated S. cerevisiae strains in the Saccharomyces sensu stricto group. Karyotype analysis of the S. cerevisiae strains resolved using pulsed field gel electrophoresis (PFGE) showed that the strains are typically associated with different types of starters. [ABSTRACT FROM AUTHOR]

Voluminous andesite and dacite lavas of Daisen volcano, SW Japan, contain features suggesting the reverse of normal fractionation (anti-fractionation), in the sense that magma genesis progressed from dacite to andesite, accompanied by rises in temperature. A positive correlation exists between phenocryst content (0-40 vol. %) and wt % SiO2 (61-67%). Phenocryst-rich dacites contain hornblende and plagioclase that are generally unaltered, clear, and euhedral. However, phenocryst-poor rocks contain sieve-textured plagioclase, resorbed plagioclase, and opacite in which hornblendes are pseudomorphed. Some Daisen rocks contain two coexisting pyroxenes. Many orthopyroxene phenocrysts from two-pyroxene lavas have high-Ca overgrowth rims (up to 50 µm), a feature consistent with crystallization from a higher-temperature magma than the core. Rim compositions are similar from phenocryst to phenocryst in individual samples. Temperatures of 800-900°C are obtained from the cores, whereas temperatures of 1000-1100°C are indicated for the rims. Lavas ranging from aphyric andesite (∼61 wt % SiO2) to phenocryst-rich dacite (∼67 wt % SiO2) have similar 87Sr/86Sr (0·7045-0·7052) and 143Nd/144Nd (0·5127- 0·5128). Isotopic variability within Daisen volcano is likely to be mantle-derived, reflecting isotopic variability within the magma source region associated with a single mantle diapir. The Daisen andesites and dacites have the same trace element signatures as the associated basalts and were probably derived from primary magmas at the same general depth (∼60 km). Our interpretation is that mantle-derived hydrous magnesian andesite, generated in the same mantle diapir as coexisting basalt magma, may be parental to the hydrous calc-alkaline magmas in Daisen volcano. We suggest a two-stage process, involving mid-crustal solidification of bodies of this calc-alkaline magma followed by varying degrees of partial melting from body to body, to produce the magmatic trends and phenocryst zoning patterns observed. The heat required for this melting, according to our model, was supplied by the intermittent rise of subjacent basaltic magma. [ABSTRACT FROM AUTHOR]

Five immortal cell lines derived from a Li-Fraumeni syndrome patient (MDAH 087) with a germline mutant p53 allele were characterized with respect to telomere length and genomic instability. The remaining wild-type p53 allele is lost in the cell lines. Telomerase activity was undetectable in all immortal cell lines. Five subclones of each cell line and five re-subclones of each of the subclones also showed undetectable telomerase activity. All five immortal cell lines exhibited variability in the mean length of terminal restriction fragments (TRFs). Subclones of each cell line, and re-subclones of the subclones also showed TRF variability, indicating that the variability is owing to clonal heterogeneity. Chromosome aberrations were observed at high frequencies in these cell lines including the subclones and re-subclones, and the principal types of aberrations were breaks, double minute chromosomes and dicentric chromosomes. In addition, minisatellite instability detected by DNA fingerprints was observed in the immortal cell lines. However, all of the cell lines were negative for microsatellite instability. As minisatellite sequences are considered recombinogenic in mammalian cells, these results suggest that recombination rates can be increased in these cell lines. Tumor-derived human cell lines, HT1080 cells and HeLa cells that also lack p53 function, exhibited little genomic instability involving chromosomal and minisatellite instabilities, indicating that chromosomal and minisatellite instabilities observed in the immortal cell lines lacking telomerase activity could not result from loss of p53 function. [ABSTRACT FROM AUTHOR]

We present the results of 3 GHz radio continuum observations of the eight host galaxies of superluminous supernovae (SLSNe) at 0.1 < z < 0.3 by using the Karl G. Jansky Very Large Array. Four host galaxies are detected significantly, and two of them are found to have high star formation rates (SFRs > 20 M⊙ yr−1) derived from radio emission, making them the most intensely star-forming host galaxies among SLSN host galaxies. We compare radio SFRs and optical SFRs, and find that three host galaxies have an excess in radio SFRs by a factor of >2, suggesting the existence of dust-obscured star formation, which cannot be traced by optical studies. Two of the three host galaxies, which are located in the galaxy main sequence based on optical SFRs, are found to be above the main sequence based on their radio SFRs. This suggests a higher fraction of starburst galaxies in SLSN hosts than estimated in previous studies. We calculate extinction from the ratio between radio SFRs and dust-uncorrected optical SFRs and find that the hosts are on the trend of increasing extinction with metallicity, which is consistent with the relation in local star-forming galaxies. We also place a constraint on a pulsar-driven SN model, which predicts quasi-steady synchrotron radio emission. [ABSTRACT FROM AUTHOR]

We investigate the X-ray active galactic nucleus (AGN) properties of millimeter galaxies in the Great Observatories Origins Deep Survey South (GOODS-S) field detected with the Atacama Large Millimeter/submillimeter Array (ALMA), by utilizing the Chandra 7-Ms data, the deepest X-ray survey to date. Our millimeter galaxy sample comes from the ASAGAO survey covering 26 arcmin2 (12 sources at a 1.2 mm flux-density limit of mJy), supplemented by the deeper but narrower 1.3 mm survey of a part of the ASAGAO field by Dunlop et al. Ofthe 25 total millimeter galaxies, 14 have Chandra counterparts. The observed AGN fractions at are found to be % and % for the ultra-luminous and luminous infrared galaxies with log / = 12–12.8 and log / = 11.5–12, respectively. The majority (∼2/3) of the ALMA and/or Herschel detected X-ray AGNs at z = 1.5−3 appear to be star-formation-dominant populations, having / ratios smaller than the “simultaneous evolution” value expected from the local black-hole-mass-to-stellar-mass (–M*) relation. On the basis of the and stellar mass relation, we infer that a large fraction of star-forming galaxies at have black hole masses that are smaller than those expected from the local –M* relation. This contrasts previous reports on luminous AGNs at the same redshifts detected in wider and shallower surveys, which are subject to selection biases against lower luminosity AGNs. Our results are consistent with an evolutionary scenario in which star formation occurs first, and an AGN-dominant phase follows later, in objects that finally evolve into galaxies with classical bulges. [ABSTRACT FROM AUTHOR]

The arc-front volcanoes of Sumisu (31·5°N, 140°E) and Torishima (30·5°N, 140·3°E) in the central Izu–Bonin arc are similar in size and rise as relatively isolated edifices from the seafloor. Together they provide valuable along-arc information about magma generation processes. The volcanoes have erupted low-K basalts originating from both wet and dry parental basaltic magmas (low-Zr basalts and high-Zr basalts, respectively). Based on models involving fluid-immobile incompatible element ratios (La/Sm), the parental basalts appear to result from different degrees of partial melting of the same source mantle (∼20% and ∼10% for wet and dry basalt magmas, respectively). Assuming that the wet basalts contain greater abundances of slab-derived components than their dry counterparts, geochemical comparison of these two basalt types permits the identification of the specific elements involved in fluid transport from the subducting slab. Using an extensive set of new geochemical data from Torishima, where the top of the downgoing slab is about 100 km deep, we find that Cs, Pb, and Sr are variably enriched in the low-Zr basalts, which cannot be accounted for by fractional crystallization or by differences in the degree of mantle melting. These elements are interpreted to be selectively concentrated in slab-derived metasomatic fluids. Variations in K, high field strength element and rare earth element concentrations are readily explained by variations in the degree of melting between the low- and high-Zr basalts; these elements are not contained in the slab-derived fluids. Rb and Ba exhibit variable behaviour in the low-Zr basalts, ranging from immobile, similar to K, to mildly enriched in some low-Zr basalts. We suggest that the K-rich mica, phengite, plays an important role in determining the composition of fluids released from the downgoing slab. In arc-front settings, where slab depth is ≤100 km, phengite is stable, and the fluids released from the slab contain little K. In back-arc settings, however, where the slab is at 100–140 km depth, phengite is unstable, and K-rich fluids are released. We conclude that cross-arc variations in the K content of arc basalts are probably related to differing compositions of released fluids or melts rather than the widely held view that such variations are controlled by the degree of partial melting. [ABSTRACT FROM AUTHOR]