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Microchip technologies have received considerable attention, due to their competitive advantages, especially in regards to reduced sample and reagent consumption, analysis time, and easy operation. This approach has been successfully used to analyze DNA, amino acids, proteins, and carbohydrates. In the present study, we showed the potential of microchip technologies for the biomarker analysis, blood carbohydrate analysis on microchip electrophoresis, quantitative analysis of protein with antigen-antibody reaction on microchip, and the detection of malaria-infected erythrocyte with a cell microarray chip.

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A Japanese X-ray Free-Electron Laser (XFEL) facility is under construction at SPring-8 in Hyogo prefecture as one of the key technologies of national importance and its completion is scheduled in spring 2011. This paper describes an outline of the XFEL facility and overviews its application feasibility to develop science frontier. A small prototype accelerator of the XFEL built for a proof-of-principle experiment has provided stable and intense Extremely Ultra-Violet (EUV) FEL for user experiments since May 2008. Science frontier being opened using EUV FEL is also introduced from the viewpoint to give readers clear image on science fields developed by the XFEL.

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The authors have described the unique points of the ultra-high intensity laser driven proton and ion sources which include point like source, ultra-short burst, diverging beam with wide energy spectral band. They emphasize that such significant features should be taken into account in the real applications. Then the features of the laser source can make benefit. In the present stage, a thin layer activation technique and the relevant subjects of proton and ion irradiation to the practical materials are good candidate of this technique. The future medical application is also described briefly.

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The brain is one of the most complicated structures in nature. Zebrafish is a useful model to study development of vertebrate brain, because it is transparent at early embryonic stage and it develops rapidly outside of the body. We made a series of transgenic zebrafish expressing green-fluorescent protein related molecules, for example, Kaede and KikGR, whose green fluorescence can be irreversibly converted to red upon irradiation with ultra-violet (UV) or violet light, and Dronpa, whose green fluorescence is eliminated with strong blue light but can be reactivated upon irradiation with UV or violet-light. We have recently shown that infrared laser evoked gene operator (IR-LEGO) which causes a focused heat shock could locally induce these fluorescent proteins and the other genes. Neural cell migration and axonal pattern formation in living brain could be visualized by this technique. We also can express channel rhodopsine 2 (ChR2), a photoactivatable cation channel, or Natronomonas pharaonis halorhodopsin (NpHR), a photoactivatable chloride ion pump, locally in the nervous system by IR. Then, behaviors of these animals can be controlled by activating or silencing the local neurons by light. This novel strategy is useful in discovering neurons and circuits responsible for a wide variety of animal behaviors. We proposed to call this method ‘multi-stepped optogenetics’.

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Surface acoustic wave (SAW) devices, because of their very simple structures, can be used as component parts for micro total analysis systems. We focused on a liquid flow actuator operated by SAWs and investigated highly efficient interdigital transducers (IDTs) to generate SAWs. The IDTs were fabricated by patterning Al/Cr on a LiNbO₃ substrate. In an IDT with a stripline pitch of 200μm, effective water droplet streaming was produced. We also fabricated a continuous liquid flow actuator consisting of both an IDT and a flow channel made of epoxy-based negative resist SU-8 on one chip. To diversify the liquids used, we created an actuator design in which the IDT and liquid do not directly touch one another at the partition wall. Using this chip, we succeeded in creating a continuous flow of liquid using the SAWs. When 160mW of electric power was applied, the liquid flow rate of the actuator was approximately 7.8μL/s. We experimentally found that the electric power applied to the IDT was proportional to flow velocity and that the IDT with 200μm pitch produced effective continuous liquid flow as well as water droplet streaming.

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The oxidation processes on a TiAl surface induced by a hyperthermal O₂ molecular beam (HOMB) with a translational energy of 2.2 eV was studied by X-ray photoemission spectroscopy in conjunction with synchrotron radiation. At a surface temperature of 300 K, the simultaneous growth of Al and Ti oxides accompanied with the segregation of Al₂O₃ near the surface was observed. The efficiency of oxidation for the HOMB incidence was smaller than that for O₂ backfilling (25 meV). Furthermore, the chemical compositions of oxide species (Al₂O₃, Ti₂O₃, TiO₂) on the TiAl surface were independent of the translational energy of incident O₂ molecule. The present results suggest that the oxidation on TiAl surface proceed via precursor molecular states.

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The surfaces of HOPG and Si(111) irradiated with highly charged ions (HCIs) were observed using a secondary electron microscope (SEM) and an atomic force microscope (AFM). The SEM contrast appears between irradiated and unirradiated surfaces when the fluence come to 10¹³∼10¹⁴/cm², while the fluence of 10¹⁵∼10¹⁶/cm² is necessary for the irradiation with singly charged ions. The results exhibit that the potential energy of HCI produces surface modification efficiently without disturbing bulk structure.

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Recent progress on nanotechnology including nanostructure fabrication and nanometer-scale measurement techniques, and work on biomolecules whose size is equivalent to that covered by nanotechnology, are expected to result in the creation of a new research field called nano-bio science. This article introduces our recent work on the observation of single biomolecule; reconstituted a receptor protein into an artificial lipid membrane using an atomic force microscope (AFM). An AFM is a measurement tool that enables us to observe nanometer-scale objects in a liquid environment. We also examine the orientation of the proteins in proteoliposomes with the dynamic light scattering technique (DLS). Most receptor proteins have orientations in molecules, for example the extracellular and intracellular domains. Determining the protein orientation is essential for nano-biodevice fabrication if we wish to utilize the protein's function. We also introduce our recent attempt to realize a nano-bio device; a very small device obtaining and utilizing biological functions; using our state-of-the-art nanofabrication technique and a technique for handling receptor proteins. Thus, by combining nanotechnology and biotechnology to realize nano-biodevices, we can produce ultra-small biological sensors for implantation. Further improvements are expected.

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The chemical composition and components of a synchrotron radiation (SR) irradiated polytetrafluoroethylene (PTFE) surface were investigated as a function of the annealing temperature by the X-ray photoelectron spectroscopy (XPS). When the annealing temperature of SR irradiated PTFE was less than 150 °C, almost no change was observed in XPS spectra. With increasing the annealing temperature at more than 200 °C, the relative intensity of the F 1s peak to the C 1s peak increased gradually. In addition, the intensity of the CF₂ component also increased. These results indicate that the chemical composition and components of the SR irradiated PTFE surfaces are restored by annealing. Based on the XPS spectra, the annealing effect on the chemical composition and components is discussed.

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The Mg nanoparticles have been fabricated by the gas evaporation method under the several He gas pressures. We have estimated the size of Mg nanoparticles by atomic force microscopy (AFM) observation and have studied the chemical state of Mg nanoparticles exposed to atmosphere by near-edge X-ray absorption fine structure (NEXAFS) technique. The average diameters of Mg nanoparticles fabricated under 3, 5 and 10 kPa of He are 3.6, 8.0 and 5.0 nm, respectively. It is found that the degree of atmospheric oxidation of Mg nanopaticles depends on the size of nanoparticles.

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We have studied the adsorption reaction of dimethyl sulfide (DMS: (CH₃)₂S) on the surface of Rh(PVP) nanoparticles by using AFM, XPS and NEXAFS techniques. The AFM images show the degree of dispersion of the Rh(PVP) nanoparticles depends on the amount of them. The in-situ XPS results indicate that the dissociation reaction of DMS into atomic S does not depend upon the existence of the Rh(PVP) nanoparticles. The NEXAFS results show that there is a strong chemical bonding between Rh(PVP) nanoparticle and atomic S. The ex-situ XPS results show the atomic S adsorbed on the Rh(PVP) nanoparticles partially desorb by exposing to the air.

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This paper reports the first application of high-aspect ratio PTFE microstruscute, which fabricated by synchrotron radiation induced photo-evaporation process, to enzyme-linked immunosorvent assay. The advantages of PTFE microstructure for the development of lab-on-a-chip due to the extremely high-aspect ratio microstructure and chemical stability of PTFE is discussed. The results of immunoassay shows the successful detection of analyte (mouse IgG) with detection range with 0-100ng/ml. This result suggests the successful immobilization of antibody (anti-mouse IgG goat antibody) onto the x-ray exposed surface of PTFE microstructue and successful demonstration of antigen-antibody reaction in the PTFE high-aspect ratio microstructure. We also demonstrated the detection of polychlorinated biphenyl (PCB). As the result of demonstration, we successfully detected PCB with ranging analyte concentration of 0.1-10 ng/ml.

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We developed a XAFS measurement system applicable for various sample conditions at the soft X-ray double crystal monochromator beamline (BL-10) of the SR center, Ritsumeikan University. The measurement system consists of two directly connected chambers; one in high vacuum with a newly-developed sample transfer system and another in 1 atm He. A sample decomposed by evacuation can be measured in 1 atm He gas chamber, while a sample unstable in air can be prepared in a glove box, transferred with a transfer vessel and installed in a high vacuum chamber without exposing to air. This system opens a new applicability of XAFS measurements in the soft X-ray region.

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The laser plasma soft X-ray source in the wavelength rage of 5-17 nm was developed, which consisted of the rotating drum system supplying cryogenic Xe target and the high repetition rate pulse Nd:YAG slab laser. We found the maximum conversion efficiency of 30% and it demonstrated the soft X-ray generation with the high repetition rate pulse of 320 pps and the high average power of 20 W. The soft X-ray cylindrical mirror was developed and successfully focused the soft X-ray with an energy intensity of 1.3 mJ/cm². We also succeeded in the plasma debris mitigation with Ar gas. This will allow a long lifetime of the mirror and a focusing power intensity of 400 mW/cm² with 320 pps. The high power soft X-ray is useful for various applications.

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Actin filaments in Leydig cells from mouse testes have been observed with a contact-type soft x-ray microscope with laser plasma x-ray source. The Leydig cells were fixed with paraformaldehyde, stained with Phalloidin, and observed with a confocal laser microscope prior to the observation with x-ray microscope. Obtained images by both of the confocal laser microscopy and the x-ray microscopy were directly compared and revealed that not only position of actin filaments but also the shapes can be identified each other. The actin filaments in the x-ray images were clearly recognized and their structures were obtained in more detail compared to those in the confocal laser microscope images.

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We are investigating the micromachining of silica glass using extreme ultraviolet (EUV) light from laser-produced plasma (LPP). The present investigation deals with the ablation using EUV light of around 13.5 nm and 11 nm generated in laser-produced Sn plasma and Xe plasma, respectively. CO₂ laser and Nd:YAG lasers were used as pump lasers. The EUV radiation was focused on the surface of silica glass through the meshed mask using an ellipsoidal mirror coated with gold film. The results showed that the silica glass was successfully ablated by EUV light from the Nd:YAG-LPP. The maximum ablation rate was 42 nm per shot for 11-nm light, and 25 nm per shot for 13.5-nm light. On the other hand, EUV radiation from the CO₂-LPP did not ablate the silica glass. This is presumably caused by the lower EUV irradiation intensity due to the long pulse duration of the CO₂ laser.

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Energy and flux of positrons and neutrons generated in the electron storage ring NewSUBARU by laser Compton scattering with Nd (1.064 μm,) laser beams were measured. The energy of positrons was measured with an imaging plate. The positron energy has a peak around 10 MeV. With a 3 mm thick Pb target, about 3600 positron sec^-1 can be generated and the maximum generation rate of 0.0436 positron photon^-1 can be obtained under the top-up mode operation. The generation rate is defined to be the number of positrons generated per the incident single gamma-ray photon. The energy of neutrons was measured with a time of flight. The maximum neutrons energy is around 8 MeV which agreed well with the obtained result 8.6 MeV.

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We have proposed a method for high cell culture throughput by means of a micro 3D scaffold and density with high surface-to-volume ratio, and have successfully demonstrated that the throughput and density of cell culture significantly increased under a finite regime of scaffold size and figuration. We have succeeded in obtaining high density cell culture and also found that the size and figuration of capillaries in the micro 3D scaffolds significantly affect cell culture and surface adhesion.

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Microchip technologies are expected to perform high-throughput analysis of the function of single-cells. In previous our study, we already developed a single-cell microarray chip for high-throughput screening and analysis of antigen-specific single B-cells. Using the technology of cell microarray chip, we have developed a new system for the high-sensitive and rapid diagnosis of parasitosis. The microarray chip is made from polystyrene with over 10,000 microchambers, which can accommodate 100 erythrocytes. As the result, over 1,000,000 erythrocytes were dispersed on a microarray. We could detect parasites as low as 0.0001% with spreading of human erythrocytes on the microarray followed within 15 min.

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Laser plasma x-ray source has the features such as ultra short pulse, high brilliance, monochromaticity, and focusing ability. These features are excellent compared with conventional x-ray source. In order to apply the laser plasma x-ray source to the biomedical study and to more closely research the radiobilogical responce of the cancer cell such as radiation induced bystander effect, we have developed x-ray microbeam system using laser plasma x-ray source. The absorbed dose of laser plasma x-ray was estimated with Gafchromic EBT film and DNA double strand breaks on the cells were detected by immunofluorescence staining. When the cells were irradiated with laser plasma x-ray, the circular regions existing γ-H2AX positive cells were clearly identified. The usefulness of the laser plasma x-ray on the radiobiological study was proved in this research.

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The New noble metal nanostructure for surface enhanced Raman scattering (SERS) detection in microfluidic devices was developed. In this nanovalley structure, gold nanoparticles of 40 nm diameter were assembled along grooves of 200 nm deep which were fabricated on Polydimethylsiloxane (PDMS) by the nanoimprint method. Localized plasmon resonance of the assembled gold nanoparticles in the nanovalley was expected in the near infrared region. The rapid signal response and long term stability of SERS spectra of 4,4'-Bipyridine (4bpy) aqueous solution by 785 nm irradiation were demonstrated. As for an in situ SERS measurement where the nanovalley structure was immersed in 4bpy aqueous solution, SERS appeared within 5 s after the immersion and the SERS intensity almost maintained constant value for 20 h. These results were compared to those obtained using commercial SERS nanophotonic substrate and the advantage of the nanovalley structure was discussed. It is thought that the unique nanovalley structure caused excellent effects for SERS measurements, and the availability of the nanovalley structure as detector of microfluidic device was sufficiently shown.

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The use of three-dimensional (3D) microstructures is becoming essential attempt to develop next generations' microdevices, to integrate many modules and various functions, and enhance the performance of device. In this paper, we present a new concept for lab on a chip using 3D structure and centrifugal force for high-throughput screening system, which has stacked multiple structures with 3D-interconnection.

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The effective attenuation length (EAL) is a necessary parameter to estimate the thickness of SiO₂ overlayer by X-ray photoemission spectroscopy (XPS). Inelastic mean free path (IMFP) is often used instead of EAL because EAL is scarcely known. EAL values were determined experimentally in the photon energy region from 480 eV to 800 eV using synchrotron radiation photoemission spectroscopy. EALs estimated are different from calculated IMFPs. Average values of theoretically-calculated IMFPs are close to the estimated EALs.

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The thermal degradation of a native oxide layer on the hydrogen storage alloy V₂₅Cr₄₀Ti₃₅ and the thermal desorption property of deuterium molecules were studied by synchrotron radiation soft X-ray photoelectron spectroscopy and thermal desorption mass spectrometry. Photoelectron spectra of O-1s, C-1s, V-2p, Cr-2p, and Ti-2p were observed for an as-received sample and a deuterium-ion-implanted one. Although the oxide layer changed dramatically by thermal annealing between 373 K and 473 K for the un-implanted sample, the change of the deuterium-ion-implanted sample was lying between 473 K and 573 K corresponding to D₂ desorption. The implantation of deuterium resulted in the stabilization of the surface oxide layer by approximately 100 deg.

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In this study, we propose using the anchoring effect that is one of the cognitive bias as a new approach of the encoding. And we suggest technique to apply to encoding. As a result of experiments, we found that displaying High-definition image in the early part of video effects look clear than original video. In addition we noticed that the anchoring effect appear remarkably in a low rate video coding. And if changes the video rate is smoothly, the anchoring effect is shown clearness in a high average rate video.

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In this paper, we proposed a new method for diagnosing Alzheimer's disease (AD) on the basis of electroencephalograms (EEG). The method, which is termed Power Variance Function (PVF) method, indicates the variance of the power at each frequency. By using the proposed method, the power of EEG at each frequency was calculated using Wavelet transform, and the corresponding variances were defined as PVF. After the PVF histogram of 55 healthy people was approximated as a Generalized Extreme Value (GEV) distribution, we evaluated the PVF of 22 patients with AD and 25 patients with mild cognitive impairment (MCI). As a result, the values for all AD and MCI subjects were abnormal. In particular, the PVF in the θ band for MCI patients was abnormally high, and the PVF in the α band for AD patients was low.

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This research aims to construct Sliding Mode Control (SMC) system that decreases chattering in controlled object of discrete time system. In conventional SMC, chattering has been generated by turbulence's influencing the state, and repeating operation that jumps over switching hyperplane. Then, we thought about switching hyperplane that always moved according to the change in the state. The feature is that the equal output is obtained, even if input is decreased by making a nonlinear input to zero. In this paper, a simulation is performed using a vertical driving arm and the stability and validity of the proposal method are considered.

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In this paper, it is proposed a discrete-time multivariable iterative learning control algorithm which guarantees the monotonic convergence of the tracking error norms along with the trial. It is pointed out that an interactor matrix plays an important role in the iterative learning control. Numerical simulations will be presented to confirm the validity of the proposed design.

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Most training simulators of surgery have simply required manipulation of organic models with their deformation by a single operating device. In order to operate them by various kinds of operating devices, we hereby propose a new type of force-display system based on the combination of the haptic cutting systems of knife, scissors and saw, considering the dynamics of cutting operation of materials mathematically analyzed from their corresponding physical viewpoints. The proposed system is well confirmed to represent the dynamic deformation of virtual objects during their operation inclusive of their incidental cutting force.

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We propose a novel acoustic model for speech recognition, named FCD (Frame-based Context Dependent) model. It can obtain a probability distribution by using a top-down clustering technique to simultaneously consider the local frame position in phoneme, phoneme duration, and phoneme context. The model topology is derived from connecting left-to-right HMM models without self-loop transition for each phoneme duration. Because the FCD model can change the probability distribution into a sequence corresponding with one phoneme duration, it can has the ability to generate a smooth trajectory of speech feature vector. We also performed an experiment to evaluate the performance of speech recognition for the model. In the experiment, 132 questions for frame position, 66 questions for phoneme duration and 134 questions for phoneme context were used to train the sub-phoneme FCD model. In order to compare the performance, left-to-right HMM and two types of HSMM models with almost same number of states were also trained. As a result, 18% of relative improvement of tri-phone accuracy was achieved by the FCD model.

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Road signs provide important information to guide and regulate the behavior of drivers and pedestrians to make their journeys safer and more comfortable. Therefore, we have already proposed a method for extracting and recognizing circular road signs on the basis of the color information and shape features derived from a color scene image. In the previous method, the use of lightness in images and the determination of a dynamic threshold for the binary processes have not been achieved yet. This paper proposes an algorithm to extract circular road signs on the basis of features of scene images. That is, the proposed method makes good use of lightness as well as hue and chroma. Also, the thresholds regarding the chroma and lightness in each binary process of the blue road signs are able to be automatically decided using local features in the target image. Tests on 295 images suggest that the proposed method can accurately extract circular road signs.

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Two flexible rule mining methods from incomplete database are proposed using Genetic Network Programing (GNP). GNP is one of the evolutionary optimization techniques, which uses the directed graph structure. One of the methods extracts the rules showing the different characteristics between different classes in a database. The method can obtain the rules like 'if P then Q' is interesting only in the focusing class. The other one mines interesting rules like even if itemset X and Y have weak or no statistical relation to class item C, the join of X and Y has strong relation to class item C. An incomplete database includes missing data in some tuples. Generally, it is not easy for Apriori-like methods to extract difference rules and exception rules from incomplete database. We have estimated the performances of the rule extraction using incomplete data in the environmental and medical field.

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To obtain a high control performance of adaptive fuzzy control systems, the stability guarantee should be made stricter to reduce the approximation error of the system. Avoiding the system becomes complex, this study aims to design a kind of adaptive fuzzy control system that realizes compatibility of concise stability guarantee and high control performance, and it proposes the adaptive fuzzy control system design method of the indirect controller approximation type designed based on the self-structuring fuzzy neural network. It is evaded that the approximation error element that was not able to be removed by adaptive law influences the entire control input directly, and influences are distributed, by composing an indirect type control system. Additionally, it aims at the improvement of the control performance by compensating this remaining approximation error by the robust control input element in the control input. Finally, the effectiveness of this method is verified by the computation simulation of the cart-pole system control.

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