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A fast-scanning X-ray CT system, designed for measuring dynamic events in multiphase fluids, was used to obtain the transient 2-dimensional cross sectional gas-phase distribution in a fluidized bed. The captured data was sent to a PC for image reconstruction, and the density distributions across the column cross section were visualized. Using image processing techniques, a pseudo 3-dimensional image of bubbles was obtained. The spatial and time resolutions of the system were sufficient for the measurement of ascending bubble behavior in a fluidized bed with fine particles. Bubble shape, interfacial area, and bubble holdup over the cross section can be measured by this system.

This study verified the accuracy of the speed of sound (SOS) measured by the combination method, which calculates the ratio between the thickness values of cartilage measured by using the magnetic resonance imaging (MRI) and the ultrasonic pulse-echo imaging, and investigated in vivo application of this method. SOS specific to an ultrasound imaging device was used as a reference value to calculate the actual SOS from the ratio of cartilage thicknesses obtained from MR and ultrasound images. The accuracy of the thickness measurement was verified by comparing results obtained using MRI and a non-contact laser, and the accuracy of the calculated SOS was confirmed by comparing results of the pulse-echo and transmission methods in vitro. The difference between laser and MRI measurements was 0.05 ± 0.22 mm. SOS values in a human knee measured by the combination method in the medial and lateral femoral condyles were 1650 ± 79 and 1642 ± 78 m/s, respectively (p

A spin-density-wave (SDW) for $(\mathrm{TMTSF})_{2}\mathrm{PF}_{6}$ has been reported to appear below ${T}_{\mathrm{SDW}}$ ($\ensuremath{\simeq}12\text{ }\text{ }\mathrm{K}$), with a subphase transition at ${T}^{*}$ ($\ensuremath{\simeq}4\text{ }\text{ }\mathrm{K}$). To determine the structure of the subphase, we synthesized $(\mathrm{TMTSF})_{2}\mathrm{PF}_{6}$, in which one side of the central carbon bond in each TMTSF molecule was replaced by $^{13}\mathrm{C}$, and utilized this compound in $^{13}\mathrm{C}$ nuclear magnetic resonance measurements. Below ${T}_{\mathrm{SDW}}$, the spectrum became broad and ${T}_{1}^{\ensuremath{-}1}$ decreased, in agreement with previous results. Below ${T}^{*}$, fine structures emerged in the center of the spectrum and ${T}_{1}^{\ensuremath{-}1}$ decreased exponentially. These phenomena were attributed to the emergence of commensurability at ${T}^{*}$.

A spin-density-wave (SDW) for (TMTSF)(2)PF(6) has been reported to appear below T(SDW) (=/~12 K), with a subphase transition at T* (=/~4 K). To determine the structure of the subphase, we synthesized (TMTSF)(2)PF(6), in which one side of the central carbon bond in each TMTSF molecule was replaced by (13)C, and utilized this compound in (13)C nuclear magnetic resonance measurements. Below T(SDW), the spectrum became broad and T(1)(-1) decreased, in agreement with previous results. Below T*, fine structures emerged in the center of the spectrum and T(1)(-1) decreased exponentially. These phenomena were attributed to the emergence of commensurability at T*.

Microarray techniques allow to detect genome-wide perturbations during various treatments and to measure various responses by multitude of gene probes. Toxicogenomics, in which microarray techniques are specifically used in toxicology test, has been widely recognized as one of standard safety procedures for chemicals [1-3]. Gene expression microarrays have been used particularly for screening of genes involved in specific biological processes of interest, such as diseases or responses to environmental stimuli. Such experiments adopt the “healthy state” as a control, and identify highly expressed or suppressed genes. However, few studies deal with the features of gene expression and its variation at the “healthy state” to be influenced by species, age, sex, and individual variability. In measuring the state of disease and drug response, minimally invasive blood sampling, which allows for direct measurement of immune-responsive blood cells, excels other invasive biopsy techniques upon disease diagnostics and assessment of drug response, as well as health monitoring. Blood RNA contains an enormous amount of information on expression of messenger RNA and non coding functional RNA which remains without being translated into protein. Thus, blood RNA offers an opportunity to detect subtle change in physiological state. In this chapter, we discuss the potential of the RNA diagnosis using whole blood, showing a series of whole blood microarray experiments to evaluate variations of correlation among individuals and ages [4], dietary-induced hyperlipidemia, and other stresses using specific pathogen-free (SPF) miniature pigs.

In the temperature-pressure phase diagram of the organic superconductor (TMTSF)${}_{2}$PF${}_{6}$ (TMTSF: tetramethyltetraselenafulvalene), the superconducting phase and the spin-density-wave (SDW) phase are adjacent to each other. This salt exhibits non-Fermi-liquid (NFL) behavior and superconductivity under pressure. Its superconductive property does not exist at higher pressures where Fermi-liquid (FL) behavior is exhibited. In order to investigate the origin of NFL behavior, systematic $^{13}\mathrm{C}$-NMR measurement of this salt has been assessed under pressure in a wide temperature range. At low temperatures, $({T}_{1}T){}^{\ensuremath{-}1}$ increases, and this increase is suppressed by the increasing pressure. These results suggest that applying pressure alters the electron system from the NFL to the FL state, and that antiferromagnetic fluctuations contribute to the origin of NFL behavior. The connection between the emergence of FL behavior and the disappearance of superconductivity suggests that the SDW fluctuation relates to the mechanism of the superconductivity in (TMTSF)${}_{2}$PF${}_{6}$.

It is useful for maturity evaluation of regenerating cartilage to measure the temporal change of its stiffness. In this study, a laser and hydrophone-based measurement of ultrasound vibration applied to the measuring object (sample) is investigated for evaluating the stiffness of thin regenerating cartilage sample. Surface particle velocity and acoustic pressure of the sample when applying sinusoidal ultrasound to the sample are measured by a laser Doppler vibrometer and a hydrophone, respectively. Then the acoustic impedance is evaluated by using the measured particle velocity and acoustic pressure. The feasibility of this method was investigated by conducting fundamental experiments using agar-based homogeneous phantoms. Moreover, this method was also applied to in vitro measurements using auricular cartilage samples regenerated in beagles.

A comparison between ultra-fast X-ray CT and a wire-mesh sensor is presented. The measurements were carried out in a vertical pipe of 42 mm inner diameter, which was supplied with an air–water mixture. Both gas and liquid superficial velocities were varied. The X-ray CT delivered 263 frames per second, while the wire-mesh sensor was operated at a frequency four times higher. Two different gas injectors were used: four orifices of 5 mm diameter for creating large bubbles and gas plugs and a sintered plate with a pore size of 100 μm for generating a bubbly flow. It was found that the wire-mesh sensor has a significantly higher resolution than the X-ray CT. Small bubbles, which are clearly shown by the wire-mesh sensor, cannot be found in the CT images, because they cross the measuring plane before a complete scan can be performed. This causes artifacts in the reconstructed images, instead. Furthermore, there are large deviations between the quantitative information contained in the reconstructed tomographic 2D distributions and the gas fractions measured by the sensor, while the agreement is very good when the gas fraction is obtained by a direct evaluation of the X-ray attenuation along the available through-transmission chords of the tomography set-up. This shows that there is still potential for an improvement of the image reconstruction method. Concerning the wire-mesh sensor it was found that the gas fraction inside large bubbles is slightly underestimated. Furthermore, a significant distortion of large Taylor bubbles by the sensor was found for small liquid velocities up to 0.24 m/s. This effect vanished with growing superficial water velocity.

It is important in regenerative medicine to evaluate the maturity of regenerating tissue. In the maturity evaluation of regenerating cartilage, it is useful to measure the temporal change in elasticity because the maturity of regenerating tissue is closely related to its elasticity. In this study, a quantitative elasticity evaluation of extracted regenerating cartilage samples, which is based on the laser Doppler measurement of ultrasonic particle velocity and calibration, was experimentally investigated using agar-based phantoms with different Young's moduli and regenerating cartilage samples extracted from beagles in animal experiments. The experimental results verified the feasibility of the proposed method for the elasticity evaluation of regenerating cartilage samples.

The scheduled test presented here will become one of the prcliminary tcsts for keeping an unmanned airship in a position in the lowcr stratosphcrc as a pcrmancnt platform that may supplcmcnt functions of satellites. This test will be a beginning of technology dcvclopmcnts that realize commercial utilization of thc lower stratosphere (approx. 20km altitude). A test will be conducted in thc fall of 1995, choosing a goodwcathcr condition, to makc an unmanned airship model hover at about 100m abovc the ground. In this tcst, a pair of vectored thruster will be placed in thc fore part of the airship hull, and thcy will bc powcrcd via transmitted microwave from the ground. In this papcr, wc will introduce an outlinc of the test, and problems contained in thcm, to station an unmanncd small-scalc airship in thc air at a lowcr altitude by microwave.

A fast-scanning X-ray CT system was used to obtain the transient 2-dimensional cross sectional gas-phase distribution in a fluidized catalyst bed with fine particles. The captured data was sent to a PC for image reconstruction, and the density distributions across the horizontal cross-section were visualized. Using image-processing techniques, pseudo 3-dimensional images of bubbles and the density distribution across the vertical cross-section were obtained. The bubble structure was studied based on these images and the results obtained previously in a 2-dimensional fluidized bed. It was found that bubble shape was not spherical, but that the bubble ascending in a fluidized catalyst bed consisted of some smaller bubbles.

It is important for regenerative medicine to evaluate the maturity of regenerating tissue. In the maturity evaluation of regenerating cartilage, it is useful to measure the temporal change of elasticity because the maturity of regenerating tissue is closely related to its elasticity. In this study, an elasticity evaluation method for the extracted regenerating cartilage sample, which is based on the laser Doppler measurement of ultrasonic particle velocity, was experimentally investigated using agar-based phantoms with different elastic moduli and the regenerating cartilage samples extracted from beagles in animal experiments. In addition, the experimentally-obtained elasticity was compared with the result of a static compression test. These results verified the feasibility of the proposed method in the elasticity evaluation of regenerating cartilage samples.

In a fluidized catalyst bed, the reactant gas transfers from the bubble phase to the emulsion phase and reactions proceed in the emulsion phase. The catalyst particles around the bubbles should contact the gases containing a high concentration of the reactants. Therefore, the effect of the catalysts around the bubbles is very important for estimating the conversion and selectivity in the reactor. In order to study the role of these catalysts, the hydrogenation of carbon dioxide was carried out in a fluidized catalyst bed. Based on the results, the amount of the catalyst that was effective for the reaction was calculated. In addition, the shape of the bubbles ascending in the fluidized catalyst bed was observed using a fast X-ray computer tomography (CT) scanner. The structure of the bubbles in the fluidized catalyst bed was very complicated and the surface area of the bubbles was much greater than the obtained when assuming spherical shaped bubble. By assuming that effective catalysts existed around the bubbles, the thickness of catalyst layer was obtained. Finally, the 3-dimensional images of the catalyst layers around the bubbles were reconstructed.

To simulate the flow in a three-dimensional porous structure, we have used the Lattice Boltzmann method (LBM). The distribution functions for flow, temperature, and concentration fields are solved to simulate the regeneration process of diesel particulate filter (DPF). For a benchmark study, we have conducted the calculation in simple geometry. To change the flow characteristics such as porosity and tortuosity, obstacles of different number and size are selected, which are randomly placed in the duct. The flow pattern is changed with obstacle size even at the same porosity. To confirm the validity of our calculation, the results are compared with the empirical relationships of the Blake–Kozeny and Ergun equations, in the non-dimensional form using the Ergun coordinates of Reynolds number and friction factor. Numerical results show good agreements with the empirical predictions. Soot combustion is well simulated to show the effects of oxygen on the reaction rate. Finally, the real porous geometry has been tested. The porous structure of Ni–Cr metal has been obtained by the three-dimensional computer tomography technique. Results show that the inhomogeneous flow is observed, and there are regions where the temperature is locally higher. This information is indispensable for the better design of DPF. LBM can be a good tool for combustion simulation in porous media.

In hard X-ray phase imaging using interferometry, the spatial resolution is limited by the pixel size of digital sensors, inhibiting its use in magnifying observation of a sample. To solve this problem, we describe a digital phase contrast microscope that uses Zernike’s phase contrast method with a hard X-ray Gabor holography associated with numerical processing and spatial frequency domain filtering techniques. The hologram is reconstructed by a collimated beam in a computer. The hologram intensity distributions itself become the reconstructed wavefronts. For this transformation, the Rayleigh- Sommerfeld diffraction formula is used. The hard X-ray wavelength 0.1259 nm (an energy of 9.85 keV) was employed at the SPring-8 facility. We succeeded in obtaining high-resolution images by a CCD sensor with a pixel size of 3.14 μm, even while bound by the need to satisfy the sampling theorem and by the CCD pixel size. The test samples used here were polystyrene beads of 8 μm, and human HeLa cells. We thus proved that the resolution 0.951 μm smaller than the pixel size of CCD (3.14 μm) was achieved by the proposed reconstruction techniques and coherent image processing in the computer, suggesting even higher resolutions by adopting greater numerical apertures.

This paper describes numerical analysis of transient heat transfer in a metal specimen during high-power laser irradiation. Three-dimensional finite element models of the heat flow are developed and solved, where both the convection and the radiation effects from the surfaces and the temperature dependence of all thermo-physical properties are taken into account. In this calculation, properties of iron (SS400) are used. Continuous (CW) laser irradiation of which maximum heat input 320 W, corresponding to 4 kW laser power, is applied to metal with stationary and a constant moving velocity conditions. The laser beam shapes are assumed circular or elliptical. We investigate the effects of heat input on the temperature distribution and its response based upon the model. As a result of the simulation, the heat-conduction effects are the most significant factor affecting the heat transfer processes, but the convection and radiation effects from the surface are negligible under the present conditions. Only a very thin layer (less than 0.5 mm) near the surface heated by the heat input can be high temperature regions. Simulated temperature responses along the central axis are compared with experimental results of temperature distribution obtained by a two-dimensional infrared thermometer, and both results are in good agreement, which indicated the validity of the present models. The maximum cooling rate can be estimated in the heated region, where the cooling rates is typically 103 - 104 °C/s, linearly depending on the heat input. Experimental results of laser hardening on the iron (SS400) specimen are compared with the cooling rate of these simulated results. The dependency of the hardening on the cooling rate is obtained.This paper describes numerical analysis of transient heat transfer in a metal specimen during high-power laser irradiation. Three-dimensional finite element models of the heat flow are developed and solved, where both the convection and the radiation effects from the surfaces and the temperature dependence of all thermo-physical properties are taken into account. In this calculation, properties of iron (SS400) are used. Continuous (CW) laser irradiation of which maximum heat input 320 W, corresponding to 4 kW laser power, is applied to metal with stationary and a constant moving velocity conditions. The laser beam shapes are assumed circular or elliptical. We investigate the effects of heat input on the temperature distribution and its response based upon the model. As a result of the simulation, the heat-conduction effects are the most significant factor affecting the heat transfer processes, but the convection and radiation effects from the surface are negligible under the present conditions. Only a ver...

5-Aminolevulinic acid (ALA) is a photosensitizer used in photodynamic therapy (PDT) because it causes preferential accumulation of protoporphyrin IX (PpIX) in tumor cells, where it forms singlet oxygen upon light irradiation and kills the tumor cells. Our previous study demonstrated that PpIX enhances generation of reactive oxygen species by physicochemical interaction with X-rays. We investigated the effect of ALA administration with X-ray irradiation of mouse B16-BL6 melanoma cells in vitro and in vivo. ALA facilitates PpIX accumulation in tumor cells and enhances ROS generation in vitro. Tumor suppression significantly improved in animals treated with fractionated doses of radiation (3 Gy × 10; total, 30 Gy) with local administration of 50 mg/kg ALA at 24 h prior to fractional irradiation. These results suggest ALA may improve the efficacy of cancer radiotherapy by acting as a radiomediator.