A new measurement system for fault location in optical waveguide devices is presented. The system consists of a fiber-optic Mach-Zehnder and a bulk-type Michelson interferometers. The spatial resolution of the scatter distribution is <380 microm, which is limited by the averaging time. The minimum detectable backscattered power is -116 dB relative to the light power propagating in the waveguides. Preliminary experimental results using single-mode fibers <10 cm long are demonstrated.

The finite size effect on the phase transition in PbTiO3 fine particles is described. Very small crystals with an average diameter of 14.2 nm were obtained by lowering the calcination temperature to 400° C. Raman scattering measurements of such fine particles were carried out to study the dependence of the phase transition temperature on the particle size. The X-ray diffraction pattern was also measured to study the tetragonality, c/a ratio. The results strongly suggest the presence of a critical size below which the ferroelectric state becomes unstable. The critical size determined by Raman measurements was 10.7 nm.

The clinical data and development of 8 cases with subependymal cysts detected on neurosonography in the neonatal period were studied, and the prognosis was found to vary. Also, clinico-pathological examination of 15 autopsied cases of congenital subependymal cysts (SEC) was performed, with immunohistochemical staining involving neuron-specific enolase in three cases, which revealed that congenital SEC are often complicated by various degrees of brain and heart anomalies, and suggested that SEC might occur in a wide gestational age range, with various causes. Therefore, it is important in the future to determine the agents which cause destruction of the subependymal germinal matrix.

We describe a configuration of the integrated-optic spectrometer based on Fourier-transform spectroscopy. The original source spectrum has been successfully retrieved with 20 GHz resolution by the spectrometer implemented in a silica-based planar waveguide.

We demonstrate a simple manipulation of gold nanoparticles that creates a structure-dependent nanometer-scale antenna on the surface of bacteria. Our studies illuminate the concept of the "effective use of light" based on the absorption and emission of light by antennas formed on bacteria.

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CbnR, a LysR-type transcriptional regulator from Cupriavidus necator NH9, activates the transcription of chlorocatechol-degradative enzymes. To activate the transcription, CbnR needs to bind not only to the cbnA promoter but also to the inducer. In this study, the transcriptional activity and DNA-binding activity of twenty-five mutants of CbnR were analyzed. Of the 17 mutants of the DNA-binding domain, 11 mutants lost their ability to activate transcription. While most mutants without transcriptional activation did not show DNA-binding activity, Asn17Ala, Gln29Ala, and Pro30Ala retained DNA-binding activity, suggesting that transcriptional activation by CbnR requires more than its binding to promoter DNA. Of the 8 mutants of the regulatory domain, 6 mutants changed their responses to the inducer, when compared with wild-type CbnR. Interestingly, Arg199Ala and Val246Ala induced constitutive expression of the cbnA promoter without the inducer, suggesting that these mutations brought about a conformational change mimicking that induced by the inducer molecule.