Early Science Result from the Japanese Virtual Observatory: AGN and Galaxy Clustering at z = 0.3 to 3.0

We present the result of projected cross correlation analysis of AGNs and galaxies at redshifts from 0.3 to 3.0. The Japanese Virtual Observatory (JVO) was used to obtain the Subaru Suprime-Cam images and UKIDSS catalog data around AGNs. We investigated 1,809 AGNs, which is about ten times larger a sample than that used in previous studies on AGN-galaxy clustering at redshifts larger than 0.6. 90% of the AGN samples are optically-selected AGN from the SDSS and 2dF catalogs. The galaxy samples at low redshift includes many redder objects from UKIDSS survey, while at higher redshift they are mainly blue galaxies from Suprime-Cam. We found significant excess of galaxies around the AGNs at redshifts from 0.3 to 1.8. For the low redshift samples ($z<0.9$), we obtained correlation length of $r_{0} =$5--6 $h^{-1}$Mpc ($\gamma = 1.8$), which indicates that the AGNs at this redshift range reside in a similar environment around typical local galaxies. We also found that AGNs at higher redshift ranges reside in a denser environment than lower redshift AGNs; For $z=1.3 \sim 1.8$ AGNs, the cross correlation length was measured as 11$^{+6}_{-3}$ $h^{-1}$Mpc ($\gamma=1.8$). Considering that our galaxies sample is based on optical observations with Suprime-Cam at the redshift range, it is expected that blue star-forming galaxies comprise the majority of objects that are observed to be clustered around the AGNs. It is successfully demonstrated that the use of the archive through the Virtual Observatory system can provide a powerful tool for investigating the small scale environment of the intermediate redshift AGNs.Comment: accepted to PASJ, 36 pages, 21 figures, this is an accepted versio

Heat capacity of liquid transition metals obtained with aerodynamic levitation

The development of contactless measurement methods has allowed investigating the properties of molten materials at high temperatures in a controlled environment. As the sample is not in contact with any container walls while being heated, levitation techniques have an edge over traditional contact methods at elevated temperatures. Among the various thermophysical properties of interest, it has been challenging to measure heat capacity with levitation techniques because it is directly related to the emissivity of the sample. Previous studies on heat capacity measurement with various levitation techniques have produced results with large deviations, especially at elevated temperatures. In addition, there is a general lack of information on the heat capacity of liquid transition metals at temperatures exceeding 2000 K, especially using conventional calorimetry methods. In this study, we successfully obtained the isobaric heat capacity of liquid transition metals such as Co, Hf, Ir, Mo, Nb, Rh, Ru, Ti, V, and Zr with aerodynamic levitation using the newly developed “multiple-gas cooling” method. A comparison between our reported values and reference data enabled us to assess the accuracy of previous experiments and provide much needed heat capacity data for high-temperature liquid metals. This study highlights the applicability and reliability of the multiple-gas cooling method for measuring the heat capacity of liquid non-noble metals at temperatures approaching 3000 K

Phase behavior of oxidized Ce and Gd-doped (U,Zr)O₂

Re-criticality analysis of the fuel debris at the Fukushima Dai-ichi Nuclear Power Plant is the key step to ensure the safe retrieval and storage of the fuel debris. Knowledge of the amount and distribution of Pu and Gd within the fuel debris greatly contributes to such analysis as they directly affect the fission-chain reaction. However, little is known about how Pu-doped and Gd-doped (U, Zr)O₂ solid solutions oxidize and whether phases concentrated in Pu or Gd form. In this study, CeO₂ is used as a surrogate material for PuO₂ because of the similarities in their crystal structures and valence states. (U₀.₉-xZr₀.₁Cex)O₂ and (U₀.₉-xZr₀.₁Gdx)O₂ solid solutions are prepared by sintering under an argon atmosphere and oxidized at 1073 K in air for 2 hours to simulate heavily oxidized fuel debris. Samples doped with 5 at% Ce and Gd contain only an orthorhombic-U3O8-x phase after oxidation, but its diffraction peaks’ intensities decrease as the amount of dopant increases. The phase transformation of (U₀.₉-xZr₀.₁Gdx)O₂, with further oxidation, is found to be cubic-(U, Zr, Gd)O₂+x → orthorhombic-(U, Zr, Gd)₃O₇±x → orthorhombic-(U, Zr, Gd)₃O₈-x. SEM/EDS analysis reveals that Ce and Gd are uniformly distributed in the (U₀.₉-xZr₀.₁REx)O₂ (RE = Ce, Gd) samples after oxidation

The Analysis of Apoptosis in Ameloblastoma: Evaluation of Bcl-2, Bcl-X, Bax, Bak

The apoptotic behavior of ameloblastomas was studied using antibodies against the apoptosis related proteins, Bcl-2, Bcl-X, Bax and Bak. Most of the outer layer cells were predominantly stained by the antimodulating proteins, Bax and Bak. Among the Bcl-2 family, Bcl-2 was the most ubiquitously expressed protein in ameloblastomas, while Bcl-X was expressed in the greatest concentrations. The acanthomatous areas overexpressed the apoptosis modulating proteins, especially Bak. The outer layer, whose cells had higher apoptotic inhibitor activity than inner layer cells, is suggested to be an active part