Assimilation of Initial Condition of Tsunami Using Adjoint Equation Method

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

An Ancient >200 m Cumulative Normal Faulting Displacement Along the Futagawa Fault Dextrally Ruptured During the 2016 Kumamoto, Japan, Earthquake Identified by a Multiborehole Drilling Program

【研究成果】布田川断層での200 mを超える落差の発見 --火山活動と関係した断層運動の”縦ずれ”から”横ずれ”への変化--. 京都大学プレスリリース. 2022-01-28.The Mw 7.0 mainshock of the 2016 Kumamoto earthquake sequence was triggered by dextral rupture of the Futagawa fault within the Aso volcanic region, Southwestern Japan. To reproduce its faulting patterns and to reveal the geological and geophysical characteristics of the fault and surrounding lithological units, we report the results of a multiple-borehole drilling program penetrating the Futagawa fault zone. By combining core descriptions with geophysical logs, we identified >200 m of normal faulting displacement along the currently dextral strike-slip Futagawa fault. Considering previous kinematic and chronological studies of the fault, we interpret that the Futagawa fault dominantly slipped as a normal fault in a short period (∼300–87 ka) before switching to its current transtensional (dominant strike-slip) regime ∼87 ka caused by a local change in the stress field associated with the termination of the Aso caldera-forming eruptions. In the main borehole, three damage/slip zones were penetrated at depths of ∼354, 461, and 576 m. The 461 damage zone was identified as ∼45 m in vertical thickness and thicker than the other damage zones (∼3–6 m vertically) and was characterized by high fracture density and the presence of strike-slip slickenlines. Depth profiles of physical properties revealed different patterns near the three damage zones; both the resistivity and the P-wave velocity showed stronger deterioration at the 461 damage zone than the others. Based on these geological and geophysical observations, we suggest that the 461 damage zone is the primary candidate for seismogenic faulting during the 2016 Kumamoto earthquake mainshock

WDR55 Is a Nucleolar Modulator of Ribosomal RNA Synthesis, Cell Cycle Progression, and Teleost Organ Development

The thymus is a vertebrate-specific organ where T lymphocytes are generated. Genetic programs that lead to thymus development are incompletely understood. We previously screened ethylnitrosourea-induced medaka mutants for recessive defects in thymus development. Here we report that one of those mutants is caused by a missense mutation in a gene encoding the previously uncharacterized protein WDR55 carrying the tryptophan-aspartate-repeat motif. We find that WDR55 is a novel nucleolar protein involved in the production of ribosomal RNA (rRNA). Defects in WDR55 cause aberrant accumulation of rRNA intermediates and cell cycle arrest. A mutation in WDR55 in zebrafish also leads to analogous defects in thymus development, whereas WDR55-null mice are lethal before implantation. These results indicate that WDR55 is a nuclear modulator of rRNA synthesis, cell cycle progression, and embryonic organogenesis including teleost thymus development

Carrier capture and escape processes in (In,Ga)N singlequantum-well diode under forward bias condition by photoluminescence spectroscopy

Carrier capture and escape processes in the super-bright green (In,Ga)N single-quantum-well (SQW)light-emitting diode (LED) has been studied by photoluminescence (PL) spectroscopy under reverse andforward bias conditions. The PL spectra were measured at 20 K under excitation photon energies aboveand below the bandgap energy of GaN barrier layers. The PL spectra under both excitation conditionsshow green emission from the (In,Ga)N SQW layer. The wavelength-integrated PL intensity changesdrastically depending on the applied bias voltage. For the excitation below the bandgap energy of GaN(direct excitation), the PL intensity increases with increasing the forward bias voltage up to +2 V and significantreduction of the PL intensity is observed with further increase of the forward bias voltage. On theother hand, for the excitation above the bandgap energy of GaN (indirect excitation), the PL intensity rapidlyincreases up to +2 V, decreases once, increases again with the maximum value at +3.25 V, and drasticallydecreases again. These differences of the PL intensity variation reflect carrier escape and captureprocesses. That is, in the direct excitation condition, the PL intensity variation indicates the effect of theelectric field on the radiative recombination and the carrier escape processes. In contrast, in the indirectexcitation condition, it is reflected in the carrier transfer and capture processes

A new species of enkephalin precursor mRNA with a distinct 5′-untranslated region in haploid germ cells

AbstractTo elucidate the primary structure of preproenkephalin (A) mRNA expressed by haploid germ cells (round spermatids) in rat testis, we have screened a λgt11 cDNA library for preproenkephalin cDNA inserts. The largest cDNA insert contained a protein-coding sequence encoding 269 amino acid residues as well as 327 and 309 bases of the 5′- and 3′-untranslated regions, respectively. The protein-coding region plus 3′-untranslated region of the mRNA was over 99% homologous to that of brain preproenkephalin mRNA, whereas the 5′-untranslated region contained a distinct sequence including a partial sequence of intron A of the preproenkephalin gene [(1984) J. Biol. Chem. 259, 14301–14308; (1984) J. Biol. Chem. 259, 14309–14313]. Northern blot analysis using a 5′-end-specific probe showed that this type of preproenkephalin mRNA exists exclusively in the germ cells

Interplay of external and internal field effects on radiative recombination efficiency in InGaN quantum well diodes

Electroluminescence (EL) and photoluminescence (PL) properties have been investigated of the highbrightnessgreen InGaN single quantum well (SQW) diode over a wide temperature range (T = 15-300 K)and as a function of injection current level. When the necessary forward bias conditions to get a certaincurrent level are different, it is found the anomalous temperature-dependent EL efficiency varies quite differently.That is, when the current is low and thus the forward driving voltage is small, the EL quenchingobserved below 100 K for high injection current levels is less significant or even absent due to the efficientcarrier capture. This finding is consistent with decrease of the PL efficiency with increasing the biasover +2.5 V. These results indicate that the EL efficiency is significantly influenced by interplay of the internaland external fields effects on the carrier capture and escape processes in addition to the localizationphenomena caused by In fluctuations in the SQW layer

Functional Roles of Otx2 Transcription Factor in Postnatal Mouse Retinal Development▿ †

We previously reported that Otx2 is essential for photoreceptor cell fate determination; however, the functional role of Otx2 in postnatal retinal development is still unclear although it has been reported to be expressed in retinal bipolar cells and photoreceptors at postnatal stages. In this study, we first examined the roles of Otx2 in the terminal differentiation of photoreceptors by analyzing Otx2; Crx double-knockout mice. In Otx2+/−; Crx−/− retinas, photoreceptor degeneration and downregulation of photoreceptor-specific genes were much more prominent than in Crx−/− retinas, suggesting that Otx2 has a role in the terminal differentiation of the photoreceptors. Moreover, bipolar cells decreased in the Otx2+/−; Crx−/− retina, suggesting that Otx2 is also involved in retinal bipolar-cell development. To further investigate the role of Otx2 in bipolar-cell development, we generated a postnatal bipolar-cell-specific Otx2 conditional-knockout mouse line. Immunohistochemical analysis of this line showed that the expression of protein kinase C, a marker of mature bipolar cells, was significantly downregulated in the retina. Electroretinograms revealed that the electrophysiological function of retinal bipolar cells was impaired as a result of Otx2 ablation. These data suggest that Otx2 plays a functional role in the maturation of retinal photoreceptor and bipolar cells