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A variety of methods have been reported using polymerase chain reaction (PCR)-based nucleic acid testing (NAT) because of its potential to be used in highly sensitive inspection systems. Among these NATs, fusion-PCR (also called as overlap-extension-PCR) has been focused on this study and adopted to generate the fused amplicon composed of plural marker gene fragments for detection. Generally, conventional agarose gel electrophoresis followed by gel staining is employed to check the PCR results. However, these are time-consuming processes that use specific equipment. To overcome these disadvantages, the immunochromatographic test (ICT) for the detection of PCR amplicons with hapten-labels that were generated by PCR using hapten-labeled primers was also adopted in this study. Based on these concepts, we constructed the systems of hapten-labeled fusion-PCR (HL-FuPCR) followed by ICT (HL-FuPCR-ICT) for the two and three marker genes derived from pathogenic microbe. As a result, we successfully developed a two marker genes system for the pathogenic influenza A virus and a three marker genes system for the penicillin-resistant Streptococcus pneumoniae. These detection systems of HL-FuPCR-ICT are characterized by simple handling and rapid detection within few minutes, and also showed the results as clear lines. Thus, the HL-FuPCR-ICT system introduced in this study has potential for use as a user-friendly inspection tool with the advantages especially in the detection of specific strains or groups expressing the characteristic phenotype(s) such as antibiotic resistance and/or high pathogenicity even in the same species.

Nonlinear stress-strain behavior of the elastomer foams of high porosity is investigated in several types of biaxial tension, and uniaxial tension and compression. The values of Poisson's ratio for the open- and closed-cell foams are estimated to be about 0.24 almost independently of the imposed tensile strain, indicating that the foams undergo finite volume increase under tension. Unequal biaxial tensile experiments reveal no explicit cross-effect of strains between different axes in the elastomer foams: The deduced strain energy density function ( W ) has no appreciable contribution from the term of I 2 which is the second invariant of deformation gradient tensor representing the explicit cross-effect of strains, while in general W for conventional non-cellular elastomers involves finite contributions from I 2 -term. No explicit cross-effect of strains result in a unique feature in biaxial tensile behavior that the effect of the strain in one direction on the stress in the other direction is considerably small. These features in tensile behavior are commonly observed for the open- and closed-cell foams. In contrast, the cell type has a pronounced effect on the compression behavior accompanying the buckling and collapsing processes of the cells, as observed in earlier studies. The stress-strain relations in compression accompanying the cell buckling are markedly different from the expectation of W obtained from the data of biaxial and uniaxial tension where the cell bucking is not possible.

Two novel phase-separation morphology are reported in the ternary polymer blends of poly(propylene)/nylon-12/poly(lactic acid) by utilizing a high-contrast X-ray computerized tomography. One is a “mosaic-tiling” structure, where each of three components forms equally-sized droplets in a three-dimensional tessellation manner. The other morphology is a “worm-like” structure. Two components of the three form successive droplets like stripe socks. These results strongly suggest the wide variety of the phase-separation morphologies in ternary polymer blends.

Contrasts of the polymer materials under a high contrast X-ray computerized tomography (XCT) are comprehensively investigated. We developed a high contrast XCT, and demonstrated its capabilities to polymer systems, such as polymer blends. Then we got a hypothesis that the pixel values of the cross-sectional image obtained by XCT agree with the X-ray absorption coefficient at 15 keV. This hypothesis is intensively examined by using various polymers. Consequently, we propose an empirical criterion that 0.1 cm −1 difference in the X-ray absorption coefficients at 15 keV is necessary to distinguish the polymers under XCT. This criterion is also confirmed in the polymer blend systems.

Three-dimensional (3D) observation of co-continuous macropore structure was performed using laser scanning confocal microscopy (LSCM). The obtained LSCM images were reconstructed into 3D images, and further subjected to image analysis. The LSCM observation and the following image analysis provided geometrical parameters of the macropore surfaces, which cannot be obtained by classical techniques for macropore characterization, such as scanning electron microscopy (SEM) observation or mercury intrusion method. Based on the obtained structural parameters, influences of viscoelastic properties on the liquid-phase structural formation mechanism were examined.

The excess shear stress after application of large step strains in polymer blend is calculated from observed shapes of deformed droplets in immiscible matrix, based on the Doi–Ohta expression for the interface contribution to the stress. The calculation is made for droplet shapes of flat ellipsoid, rod with end caps, dumbbell and ellipsoid of revolution. The predicted excess relaxation modulus agrees very well with experimental data normalized per one droplet with the volume-averaged radius for a poly(isobutylene)/poly(dimethyl siloxane) blend with narrow distribution of droplet size. Especially, slow stress relaxation in the intermediate stage and faster relaxation thereafter predicted from the rod like and dumbbell shapes are consistent with the experimental data. For a blend of hydroxypropylcellulose solution/poly(dimethyl siloxane) with broad distribution of droplet size, the predicted excess relaxation modulus agrees reasonably well with experimental data by taking account of the size distribution.

The film specimens having the double gyroid network structure with Ia 3 ¯ d space group symmetry were prepared by solution casting of poly(2-vinylpyridine)-block-polyisoprene mixed with a small but varying amounts of polyisoprene with chloroform as a solvent. The network phase composed of poly(2-vinylpyridine) was first crosslinked with 1,4-diiodobutane and then the matrix phase composed of polyisoprene was degraded by ozonolysis to obtain “free-standing” double gyroid network texture in which the two sets of networks are interlaced without contacts with one another in vacant space via their grain boundary connections. The network structures before and after ozonolysis were investigated, respectively, by transmission electron microscopy and field-emission scanning electron microscopy with the aid of numerically calculated three-dimensional computer graphics (3d CG) of the structure. The results clarified a success of the nano-fabrication on the free-standing double gyroid structure. We propose that the 3d CG-SEM, as discussed in the text, on the morphology of the freeze-fractured surface is particularly useful for the identification of the structure.

We examined the effects of the expansion of glutamine repeats on the early stage of protein fibrillization. Small-angle x-ray scattering (SAXS) and electron microscopic studies revealed that the elongation of polyglutamine from 35 to 50 repeats in protein induced a large assembly of the protein upon incubation at 37 degrees C and that its formation was completed in approximately 3 h. A bead modeling procedure based on SAXS spectra indicated that the largely assembled species of the protein, quasi-aggregate, is composed of 80 to approximately 90 monomers and a bowl-like structure with long and short axes of 400 and 190 A, respectively. Contrary to fibril, the quasi-aggregate did not show a peak at S = 0.21 A-1 corresponding to the 4.8-A spacing of beta-pleated sheets in SAXS spectra, and reacted with a monoclonal antibody specific to expanded polyglutamine. These results imply that beta-sheets of expanded polyglutamines in the quasi-aggregate are not orderly aligned and are partially exposed, in contrast to regularly oriented and buried beta-pleated sheets in fibril. The formation of non-fibrillary quasi-aggregate in the early phase of fibril formation would be one of the major characteristics of the protein containing an expanded polyglutamine.

Microstructure of trabecular bone has been examined with a particular emphasis on surface curvatures in two-phase (trabecular and intertrabecular space— i.e., marrow space) structures. Three trabecular bone samples, quantified as “plate-like,” “rod-like,” and a mixture of these two structural elements according to the structure model index (SMI), were subjected to analysis based on (differential) geometry. A correspondence between the SMI and the mean curvature was found. A method to measure surface curvatures is proposed. The gaussian curvatures averaged over the surfaces for the three analyzed bone structures were all found to be negative, demonstrating their surfaces to be, on average, hyperbolic. In addition, the Euler-Poincare characteristics and the genus, both characterizing topological features of bone connectivity, were estimated from integral gaussian curvature (Gauss-Bonnet theorem). The three bone microstructures were found to be topologically analogous to spheres with one to three handles.

The performance of a Micro-Strip Gas Chamber in solution X-ray scattering was studied at the RIKEN structural biology beamline I of the SPring-8 facility. The practical dynamic range was confirmed to be ∼1,000,000 : 1 by measuring S −4 decay from a polystyrene latex solution. Steep troughs of scattering profile from an apoferritin solution were clearly obtained without smearing. An unfolding process of a pH jump of cytochrome c was measured. A time resolution of 500 μs was achieved.

An improved high pressure (up to 500 MPa) cell with diamond windows was developed for small-angle X-ray scattering of protein solutions. When the diamond window was subjected to high pressure, many streaks of parasitic scattering appeared. By changing the wavelength and performing simulations, it was concluded that they are Kossel lines. In order to obtain quantitative scattering data, it is essential that Kossel lines do not interfere with the beamstop. The performance of the improved cell was tested by using Apo-ferritin solutions.

The structural changes in the uniaxial drawing process of an unoriented amorphous film of poly(ethylene naphthalene-2,6-dicarboxylate) (PEN) and in the heating process of an oriented amorphous film of PEN were studied using X-ray diffraction apparatus equipped with imaging plates. This apparatus allows us to record a time-resolved series of two-dimensional patterns of wide-angle X-ray diffraction in rapid succession, and, therefore, we can follow the structural changes during uniaxial deformation and/or thermal treatment processes. The results are as follows: (1) When an unoriented amorphous PEN film was stretched below Tg (= 117 °C), it could be elongated up to a draw ratio (DR) of 4–5 via neck formation and became an oriented amorphous film. (2) In the heating process of the oriented amorphous film (DR = 3.6, 65 °C), crystalline reflections started to appear near 120 °C, accompanied by streaks on the off-equatorial layer lines. The existence of these streaks on such layer lines indicates a lattice distortion due to the axial shift of neighbouring chains along the chain axis with respect to one another. Finally the film exhibited a fibre structure (transverse isotropy). (3) When an unoriented amorphous PEN film was drawn at 150 °C, the film exhibited a fibre structure accompanied by a lattice distortion that is similar to that mentioned above, and thereafter frequently showed so-called double orientation (uniplanar axial orientation: (10)[001]) in which naphthalene rings in the main chain are preferentially aligned parallel to the film surface despite the fact that the film was deformed in the mode of uniaxial free-width drawing.