La_0.7Ba_0.3MnO₃ (LBMO) thin films known to colossal magnetoresistance were deposited for uncooled infrared bolometers. The optimum oxygen pressure was examined in the process of the laser ablated LBMO films, and films were deposited on SrTiO₃ (100), LaAlO₃ (100) and MgO (100) substrates under the optimum oxygen pressure. The lattice mismatch between these substrates and LBMO films changed the surface structure of films. In X-ray diffraction and atomic force microscope, the LBMO film deposited on SrTiO₃ (the LBMO/STO film) showed a high orientation for the substrate, and the grain growth of the LBMO/STO film was progressed. The temperature dependence of resistivity has a good agreement with that of LBMO bulk. In the near-room temperature, the LBMO/STO film showed a high TCR value, about 4%/K. Moreover, TCR values of the LBMO/STO film were over 2%/K from 300K to 335K. On the other hand, LBMO films deposited on LaAlO₃ and MgO substrates, having large substrate-film lattice mismatches, showed a low TCR value, below 2%/K, in the near-room temperature.

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Intergrain magnetoresistance (IMR) has been observed at temperatures below the Curie temperature T_C. This phenomenon is characterized by rapid resistance drop at a low applied magnetic field, followed by a slow decrease at higher magnetic fields. It has been shown that IMR occurs at the grain boundaries, and the large degree of spin-polarization characteristic of half-metallic ferromagnets enhances these effects to a large extent. In this work, we propose the spin boundaries, "Tilted Nanocolumn boundaries" providing a large IMR at the low magnetic field, and show a close correlation between the IMR value and the tilting angle of the column boundary.

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We have already developed the electrical sterilization method with the metal coating hollow fiber membrane. The sterilization mechanism was imagined that the cell membrane was broken by passing a direct current, because the leakage of intracellular contents was confirmed when bacteria were sterilized.
In this paper, the mechanism of this sterilization were focused and the possibility whether the metal coating hollow fiber membrane became a new device of gene extraction was examined. After the direct current to the membrane surface trapped Escherichia coli O157 was passed, the gene was checked. As a result, the vero toxin type 1-gene could be detected. The detection sensitivity on the gene extraction was mainly depended on the concentration of sodium dodecyl sulfate (SDS) which was an anion surfactant and the value of the direct current. The highest sensitivity in the extraction was obtained under 5% SDS and 300mA. In addition, the gene was extracted when 10⁷ or 10⁸ of Escherichia coli O157 were contained in 1ml of the real feces.
This system needed the time to extract the gene only in 10 minutes. The system was also simpler equipment which consists of the perista-pump and the power supply except the membrane.

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Electrochemical detection of specific DNA sequence was investigated by using a gold electrode immobilized with probe DNA and tris(1, 10-phenanthroline) cobalt (II) complex (Co(phen)₃²⁺) as a hybridization indicator. 25-mer probe DNA modified with a thiol group at 5' end was immobilized on a gold electrode. After the probe DNA-modified gold electrode was hybridized with complementary target DNA, the anodic peak current of 0.1mM Co(phen)₃²⁺ increased as to the concentration of target DNA in the range from 10^-7M to 10^-4M. On the other hand, no current increase was observed when it was hybridized with poly-deoxy A as non-complementary DNA in the same range of concentration.

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To clarify the potential as atomic force microscope (AFM) memory media, nanometer-scale mechanical processing properties of polycarbonate and fluorocarbon plasma-treated polycarbonate were determined by tip sliding of AFM. The surface energy of polycarbonate can be reduced by fluorocarbon plasma treatment. Furthermore, plasma treatment of polycarbonate can reduce the processing force. Nanometer-scale precise processing of polycarbonate can be realized by fluorocarbon plasma treatment. For the formation of lines, spaces and nano meter-scale fine dots, the interval pitch as minimized to 60nm using the fluorocarbon plasmatreated polycarbonate as processing media. High-density recording can be realized by nanometer-scale processing of fluorocarbon plasma-treated polycarbonate. Fluorocarbon plasma treatment can reduce the friction and improve the wear resistance of polycarbonate. Therefore, the friction durability corresponding to the reliability of data reproduction were markedly improved.

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