Reflectivity spectra of layered MoO3 single crystals have been measured at 6 K in a wide energy range up to 25 eV. The spectra exhibit remarkable anisotropy for the polarization E∥c and E∥a. Optical constants have been derived through the Kramers-Kronig analysis. The fundamental absorption tail located below 3.7 eV displays an exponential dependence on photon energy for both polarizations. It is found that two luminescence bands peaking at 2.93 and 3.58 eV are stimulated under the excitation with photons in the fundamental absorption region. Their decay behaviours are also examined at 8 K. With use of the discrete variational Xα (DV Xα) method, the electronic structure of an embedded [MoO4] cluster has been calculated for better understanding of the optical properties of MoO3. The calculated results are favourably compared with the experimental data.

Chromosomal translocations in T-cell malignancies frequently involve the T-cell receptor (TCR)a/d locus at chromosome 14q11. Although 14q11 abnormalities are found in about 10% of adult T-cell leukemia (ATL) cases, until now there has been no direct evidence showing involvement of the TCR locus in ATL-a malignancy closely associated with HTLV-1 infection. The breakpoints of T-cell malignancies most commonly occur within the Ja or Jd region of the TCR locus. In ATL, however, despite extensive searching no breakpoint has yet been found in that region. Using fluorescence in situ hybridization with a panel of cosmid and bacterial artificial chromosome probes derived from chromosome 14, including the variable region of the TCRa locus, comprehensive analysis of an ATL patient carrying inv(14)(q11q32) revealed that the TCR locus was indeed involved in this inversion. Molecular cloning of the breakpoint revealed the juxtaposition of TCR Va to the 14q24 region as a result of two consecutive inversions: inv(14)(q11q32) and inv(14)(q11q24). We also found a gene near the breakpoint at the 14q24 region that is downregulated in this ATL patient and is assigned in the database as a pseudogene of ADAM21 (a disintegrin and metalloproteinase domain 21). Our expression analysis, however, showed that this pseudogene was actually expressed and was capable of encoding a protein similar to ADAM21; thus we have named this gene ADAM21-like (ADAM21-L).

The hardening of (Bi0.5Na0.5)0.85Ba0.15TiO3 (BNBT15) piezoelectric ceramics was investigated by adding raw materials with Bi0.5Na0.5MnO3 (BNM). BNBT15-BNM exhibited a single phase of BNBT15. BNM acts as a sintering aid for BNBT15 to produce domain pinning, and produces tetragonality based on BaTiO3 for increased stability. BNBT15-BNM hardens piezoelectric material with low Mn content, increasing the coercive field and mechanical quality factor. The mechanical quality factor of BNBT15-BNM (0.75 wt%) exceeded 1200. In high-power conditions, BNBT15-BNM (0.75 wt%) exhibited a vibration velocity twice that of hard-PZT. The quality factor gradually decreased with a high vibration velocity. The equivalent stiffness slightly decreased with strain, and the mechanical nonlinearity was much less than that of hard-PZT. BNBT15-BNM (0.75 wt%) has superior high-power properties, and is expected to be a candidate material for use in lead-free piezoelectric ceramics in high-power applications.

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