The March 11, 2011 Tohoku earthquake tsunami disaster devastated the Pacific coast of northeastern part of Japan. The large number of casualties more than 19,000 and several types of tsunami impact such as inundation in a large area, destructive force destroying houses, buildings, infrastructures, road, and railways, and change of topography due to the erosion and deposition are reported. We have been obtaining results of field surveys as well as numerical simulation and satellite image analysis with ground truth data, to obtain the data of the tsunami and its disaster, and identify extent of tsunami inundation and damage. The fore front of the tsunami research are introduced.

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The concept of rapid prototyping was created based on a technique of making a block copy for printing newspapers. It took a long time till the usefulness of the concept was accepted. A wide variety of practicing the concept was created. The patent application for the concept was abandoned due to law evaluation of the concept. Several modifications adopting the same concept were patented by others due to failure to disclose the modifications.

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A sutrSOpm resolution electron microscope is used for in-situ study of lithium ion battery. Our developed model battery consists of a LiMn_2O_4 nanowire(NW), both ends of which connect Pt and ILE/LTO/Cu electrodes. Simultaneous observations of charge/discharge by cyclic voltammetry (CV), and electron microscope and diffraction images showed that the NW works reversible even when the cubic spinel structure has transformed into tetragonal due to local excess intercalation.

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MEMS play important roles as key components in systems. However it is not easy to be used in a market because these require heterogeneous knowledge and expensive facilities. Training of MEMS engineers who have practical experiences, accumulation and its exploitation of experiences and sharing of facilities are required for MEMS to be used in a market. Technical approaches for the practically applicable MEMS as integration with circuit and packaging will be presented as well.

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We propose a ferroelectric dipole electret (FDE) consisting of a polarized ferroelectric for output power enhancement in electrostatic vibration energy harvesters. Lead zirconate titanate (PZT) ceramics were employed to develop the FDEs. For comparison, a conventional electret was also prepared by implanting charges into a 10-μm thick CYTOP polymer by using point-to-grid corona discharging method. Output power was evaluated from a vertical-type capacitive energy harvester at acceleration 4.9 m/s^2, frequency 20 Hz, and initial air gap 0.36 mm. The maximum output power of FDE harvester is 8.6 μW, a 1.7-fold increase over a CYTOP polymer electret harvester. The FDE demonstrated the higher potential compared to the conventional polymer electret.

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This paper shows the optimization of the structure of the electromagnetic energy harvester consisting of the sputtered NdFeB film on high aspect ratio Si trench and the Au serpentine coil. The magnetic flux density change is caused by distance change between coil and magnet film on the corrugated Si. In order to maximize the harvesting energy, the optimum parameters such as width, depth of Si trench, and coil size are investigated by FEM analysis and theoretical calculation. Assuming the trench depth of 400 μm the vibration amplitude of 400 μm_<p-p> and the frequency of 100 Hz the maximum output power of 12 nW and the maximum electromotive force of 4 mV are obtained by 60 μm and 80 μm, respectively.

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This paper presents design and experimental characterization of a vibration electret energy harvester with vertical electrets. The electromechanical optimal design of the in-plane energy harvester with comb electrodes was made to maximize the mass and the capacitance variation in a given area and thus to maximize the output power. A MEMS electret energy harvester is microfabricated using the SOI technologies without any assembling processes. Soft X-ray charging is employed to implant electrons into the vertical electrets with narrow gap opening. Uniform surface potential is obtained up. to the depth 10 times of the gap opening. An output power of 0.4 μW has been obtained at 300 Hz and 2g, which corresponds to the effectiveness as high as 14.8 %.

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We proposed a vertical vibratory energy harvester using polymer electret and dielectric. A proof mass consists of counter electrode and dielectric beneath it, which faces with electret on base electrode on a substrate. Since dielectric prevents discharge from electret to counter electrode, a narrow gap between mass and electret is feasible. The device can generate the power as far as the input acceleration is enough for the mass to reach the electret surface, even at the frequency apart from the resonant one. It leads to high output power for broad frequency bandwidth. There is almost no hysteresis between the up sweep curve and down sweep one. Thus, the device can generate a stable output against frequency change.

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This paper describes electrostatic energy harvester employing electrets with ball bearing system. In this device, a electret plate was supported using micro balls and was embedded between electrode plates. Electret was fabricated on the both sides of the electret plate. When external force is applied to the device, electret plate can laterally vibrate due to rolling of the micro ball, and electric energy is outputted to external circuit. As a result, output power spectrum was broad from DC to 30 Hz, and maximum power of 12.3 nW was generated at 20 Hz. This value was 3.3 times higher than that of conventional single side electret generators.

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We developed inner water circulation MEA for portable DMFC uses by introducing permeation controlled layer between anode GDL and catalyst layer. This layer features to have low permeability and reduces saturation at anode catalyst layer. Water produced at cathode catalyst layer diffuses back from cathode to anode through the membrane.

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Recently microstereolithography techniques have been actively developed as a method to produce 3-D microdevices. Especially microtubes are expected to be applied to micro fluidic devices and artificial blood vessels in biology and medical science. Microtubes fabricated by conventional microstereolithography systems have rough surface due to direct laser writing. Here we propose and experimentally demonstrate a novel method using an optical vortex. In our method, since microtubes are fabricated by scanning optical ring of optical vortex, the microtubes have smooth surface. Such smooth microtubes are expected to be used for highly efficient micro fluidic devices and high-quality artificial blood vessels.

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Microorganisms' mass cultivation in open-environment is demanded to accelerate the use of microorganisms itself and its metabolite to reduce the dependence on fossil resources. In tissue engineering, cell-laden microfibers which grow biological cell within the fiber has a high profile. One approach is to structure fiber with calcium alginate. In order to apply this technique in microorganisms' cultivation, we proposed a process to fabricate hollow microfiber in this study. We also experimentally verified that porous surfaced hollow microfiber worked as protection for inside microorganisms from viruses. Our results show that hollow microfiber has a potential to culture microorganisms massively in open-environment.

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We developed a novel technique for patterning a SAM (Self-assembled monolayer) using VUV (Vacuum ultra violet) light irradiation. First, after a SAM of ODS (octadecyltrimethoxysilane) was formed on a SiO_2-coated Si substrate, its surface was irradiated with VUV light for several different lengths of time. Then, in order to find irradiation time required for complete removal of the SAM, the wettability of the surface was analyzed by measuring contact angles of a droplet on it, and the carbon content at the surface was analyzed using XPS (X-ray photoelectron spectroscopy). Moreover, a SAM of AHAPS (n-(6-aminohexyl)aminopropyltrimethoxysilane) was patterned by irradiation of VUV light through a quartz glass plate having line and space patterns, and the patterning accuracy was evaluated by binding fluorescent dyes to remaining AHAPS molecules.

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A novel droplet generator equipped with flow-control has been developed for the formation of high speed, high frequency consecutive droplets up to 80m/s, 150k drops/s. The high speed water droplets with abrasive using this generator have been studied for surface polishing to gain a smooth, reflective surface. The droplets and jet polishing were compared at same conditions for processing speed and for processed surface roughness. Glasses with optically polished and frosted were used. The differences were small at experimental conditions.

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In this paper, turning experiments on a single crystal silicon substrate under atmospheric and high hydrostatic pressure are conducted. And their surface roughness is compared. Generally, hard/brittle materials, such as glass and silicon, are difficult to be machined. However, it has been found that such materials can be machined in ductile manner when high hydrostatic pressure is applied. In order to utilize this effect, we developed precision machining device that works in high pressure environment up to 250MPa. The experimental equipment consists of high pressure vessel, gate-shaped frame for storing and suppressing the pressure vessel, pump system, NC machining device, and a controller. Turning experiments are carried out under atmospheric and 150MPa environment. The surfaces of the machined specimens were observed by laser microscope and their surface roughnesses were compared. We confirmed that the surface roughness of silicon substrate was enhanced by applying high hydrostatic pressure.

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In this study, we demonstrate the fabrication of polymeric dry microneedle electrodes that can be applicable as flexible electrodes for biopotential measurements. Microneedles can penetrate the high-impedance stratum corneum, which eliminates the preparation that disc electrodes require. For the application, needles must be stiff enough to penetrate the stratum corneum and the conductive layer of the needle must be protected from peeling off during the insertion. We manufactured the electrode substrate using negative photoresist, SU-8, utilizing diffraction of UV light. After the conductive layer was vapor deposited onto the substrate, we coated the electrode surface with nanoporous parylene film as a protection layer. When the skin-contact impedance of the electrode was measured on subject's forearm while the electrode was compressed, sufficiently low electric impedance was achieved at the pressure of 8 N. This result verified that the proposed dry electrodes satisfied the required specifications for measurement of biopotential.

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Recently, there are many cell operating researches to measure cell functions in microTAS field. We have proposed a cell trapping device having micro-channels, micro-orifices and tapered structures for single cell analysis, and fabricated the prototype by multidirectional UV lithography in short process time. In this study, we designed dimensions of the tapered structure to adjust number of trapping cells. Then, we evaluated cell trapping efficiency and number of trapped cells by trap tests of fluorescent micro-beads and plant cells.

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In this research, we propose an on-chip in vitro model based on a microfluidic device for pharmacokinetic studies. To construct an in vitro pharmacokinetic model that appropriately models in vivo conditions, physiological parameters such as the structure of internal circulation and volume ratios of each of the organs were mimicked using microfluidic networks. Pharmacokinetic study using tegafur was conducted to model the effects of biologically activate anticancer drugs. The efficacy of the anticancer drug in the target cells was successfully demonstrated using the device. This device can thus be used as an in vitro organ model to predict the pharmacokinetics of drugs in the human body.

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In this study, we have developed a microfluidic device integrated with a microfluidic probe to clarify a differentiation mechanism of pluripotent stem cells. It is difficult to evaluate efficacy of chemical reagents for the differentiation using a conventional method because cells cultured in culture dishes are exposed to the reagents homogenously. Here, we propose a novel culture method which enables exposing cells to different chemical condition by location. The device was evaluated by a computer simulation using FEM, and a flow control experiment. A control of chemical stimulation from single cell level to tissue level in a microspace could be possible by regulating flow ratio and channel size of the microfluidic probe.

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This paper proposes a mechanical liposome or cell contact system using a parylene filter and gentle downward flow for the function analysis of membrane proteins. Membrane proteins play an important role in several biological functions including signal transduction, energy production and cellular communication. For the analysis of membrane proteins, the methodology of liposome and cell trap or contact is highly demanded. In this paper, we developed the device that can trap a single liposome or multiple cells on parylene filter. By using this device, the fluorescence dye transports mediated by membrane proteins were successfully observed under confocal laser scanning microscopy. We believe that this device can accelerate the study of membrane proteins.

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This paper reports on cluster formation of stem cells under co-cultured conditions by using our original device "TASCL" which has an array of tapered holes 300μm in diameter with hydrophilically modified surfaces to prevent cell adhesion. The device can be easily incorporated into conventional cell culture protocols by just placing the device onto an arbitrary culture substrate. By seeding hepatic-differentiated iPS cells and adipose-derived stromal cells onto the device, the cells aggregated in the areas defined by the holes and self-assembled into a cluster in each microwell. The two types of cells distributed homogeneously in a cluster at first. However, in three days, the adipose-derived stromal cells migrated into the center of the cluster and self-organized into a double-layered cluster. We speculate the difference of hypoxia tolerance of each cell type is the mechanism of the self-organization.

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We present a novel method for chemotaxis assay of plant-parasitic nematode, Meloidogyne incognita by using a PDMS (polydimethylsiloxane) microchannel device. For allowing the nematodes to swim in a simple microchannel, we also developed a protocol by loading an agarose gel into microchannel with power-free pumping method. A 5-μm-wide microchannel array, which is narrower than the body width of the nematodes, can efficiently confine the nematodes in analyzed area. We numerically evaluated the chemical concentration distribution in developed microchannel and successfully related the time-dependent chemical condition to the behavior of nematodes.

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LSPR property of gold nano dots fabricated by the thermal dewetting method is studied. Effects of process conditions, i.e. the metal coating thickness, annealing temperature and annealing time, on the morphology of nano dots are studied. With the increase of annealing time and annealing temperature, dot aggregation is improved, and spherical dots are generated. In addition, the increase of the coating thickness increases dot diameter, but reduces the progression of dot aggregation. Then, the absorption spectrum of a nanodot array shows a peak due to Surface Plasmon Resonance (LSPR). It is shown that variation of the peak wavelength due to annealing conditions is attributed to change of aspect ratio of nano dots.

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This paper describes the effects of specimen size, focused ion beam (FIB) damage, and ultra-high vacuum (UHV) annealing on the mechanical properties of silicon (Si) nanowires (NWs) evaluated by tensile testing in-situ SEM. Si NWs were made from silicon-on-nothing (SON) membranes that were produced by deep reactive ion etching (DRIE) fabrication and UHV annealing. FIB system's probe manipulation and film deposition functions were used to directly bond them onto the sample stage of a tensile test device and to fabricate Si NWs. The mean Young's modulus and strength of FIB-damaged NWs were found to be 129.1GPa and 5.6GPa, respectively. After annealing in UHV, the Young's modulus was increased to 168.4GPa, whereas the strength was decreased due to morphology degradation.

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Micrometer-scale bubbles have been successfully generated by electrolysis with using carbon nanotubes (CNTs) as the electrode. The CNTs used were vertically aligned on a conductive silicon wafer. After wiring the substrate connecting to the CNTs, it was placed in NaOH solution. The CNTs were covered by air film because of hydrophobicity, however it gradually disappeared as applying voltage. It is probably originated in increasing buoyancy since bubbles are newly generated on individual CNTs. Then innumerable bubbles with 10 micrometer diameter were observed at the tips of CNTs after continuous electrolysis. This result may lead us to develop a novel technique to manipulate a single microbubble with a selective diameter by trapping at a tip of a CNT prove.

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The Mechanical property of free-standing Cu/Al_2O_3 multilayer thin film was investigated by a method of micro-bending test. The Cu and Al_2O_3 monolayer thin film and Cu/Al_2O_3 multilayer thin film were deposited on Si substrate by an electron beam deposition. Free-standing micro-beam specimens were fabricated using a focused ion beam system. The micro-bending tests were conducted using a nanoindenter. Young's moduli of free-standing thin films were estimated by FE analysis including indentation displacement. Young's moduli of Cu and Al_2O_3 films were relatively close to those of bulk material, and that of Cu/Al_2O_3 film with 20 layers was between Cu and Al_2O_3 films. On the other hand, the fracture strength of Cu/Al_2O_3 film with 20 layers was larger than that of Al_2O_3 film.

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Self-propagating exothermic reactive films are one of attractive functional materials in MEMS field. The reactive materials with nanometer-thick multilayers consisting of light metal and transition metal possess attractive features, such as instant heat generation, self-propagation of reaction, rapid cooling, reactive in every atmosphere, and no emissions. The authors propose the use of the reactive materials as local heat source for soldering in hermetic packages for MEMS. However, it is often seen that the propagation of the reaction stops at the half-way. In this paper, the size limit of Al/Ni reactive films for self-propagating explosive reaction on a Si wafer is reported first, to investigate the cause of the reaction stop. Then the influence of bonded area size on cracking in reactive soldering is presented.

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We developed new photopolymers to produce three-dimensional (3-D) carbon microstructures via two-photon microfabrication and microtransfer molding followed by thermal decomposition. The photocurable resins contain resorcinol diglycidyl ether which have not been much used as a raw material of carbon structure. They have a high carbon content and good shape retention after pyrolysis. These photopolymers are found to be ideal for two-photon microfabrication and microrransfer molding, respectively. Complex 3-D carbon microstructures such as a bunny and pyramidal models could be formed by both methods. The results of characterization of carbonized polymers indicated that the pyrolysed structures were amorphous carbon.

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Plant ovules, which are developed into seeds after fertilization, are the key organs for plant reproduction. Thus, the long-term observation of plant ovules is important to investigate embryogenesis and the development occurring inside. To realize long-term live observation, we fabricated PDMS microcage arrays for fixing ovules and performed long-term culture. First, we performed the sieving test to investigate the relationship between ovule size and different microcage widths. Next, we performed ovule culture for a week using microcage arrays developed based on the results of sieving tests. We successfully positioned and fixed ovules inside the microcages and confirmed that the ovules did not move from their original positions even though the culture dish was frequently moved for observation and incubation. Furthermore, we confirmed that ovules were easily spotted and observed owing to the fixation by microcage arrays.

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We report that the allergen detection chip and the regent delivery chip. For the medical treatment regarding an allergy disease, it is important to detect and eliminate causative allergens from several hundred kind of allergen. The final goal of our research is to develop the allergy detection device that enables us to detect causative allergens from a few drops of human's blood. We detect allergy to process photos on the allergen detection chip. The regent delivery chip was proposed. The design of the micro channel that is able to supply 5 kinds of the reagent properly was verified. The experimental results showed its effectiveness.

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Though medical technology has made a great progress recently, there are still many diseases difficult or impossible to cure. One of the problems is late detection of the diseases. We propose palpable endoscopes with the pressure sensor to develop the early-detection of diseases. Cancer tissue is known to be harder than normal tissue. In this study, In order to develop the palpation technology, we made a biological model of organs made of jelly. At first, we investigated whether jelly had young's modulus compatible with organs. The jelly with 15 % of concentration and 20 C of storage temperature was found to be appropriate. Next, we made the biological model of a cancer embedded in a normal tissue by using the jelly and then measured the young's modulus. We believe the proposed model is readily applicable to develop the next generation palpation technology.

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In this study, we have developed three-dimensional (3-D) piezoelectric micro power generation devices using a 3-D ceramics molding process based on microstereolithography. In experiments, we fabricated a piezoelectric spiral element, which can generate output voltage by applying multidirectional loads. The generated electrical power attained to 123 pW by applying the maximum load of 2.8 N at 2 Hz along the helical axis. However, the electrical power generation is insufficient to use for practical applications. To improve the electrical properties of spiral element, we tried to use a tow-step sintering process. As a result, piezoelectric constant d_<31> of the sintered body produced by the two-step sintering process attained to -40.0 pC/N that is better than that of a conventional sintered body. Moreover, we simulated the distribution of electrical potential of a spiral piezoelectric element. From the result, We found that the output voltage of the selective electrode was 30 times higher than that of uniform electrode.

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In this study, we report the optimization of electrode design for increasing output power of the vibration electrostatic energy harvesters. The output power depends on the capacitance change and its frequency. Without consideration for fringe effect of a parallel-plate capacitance, the narrower electrode pitch L is, the larger output power. However, under actual conditions, power output is limited by fringe effect. To consider fringe effect, the optimum electrode dimension changes due to the distance between the electret and counter electrode. By using FEM analysis with fringe effect, we find the characteristic of fringe effect at parallel-plate capacitor, and then the optimum width of counter electrode fFand electrode pitch L are obtained.

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In this paper, we describe design and development of proof-of-concept prototype of a micro heat engine for an in-liquid micro robot. There are two main problems to develop a micro robot within 1mm^3. Those are a sticky problem and an energy source problem. To solve those problems, we look at the natural world and found out almost all micro animate beings are living in liquid such as microbes and water fleas. They harvest energy by eating foods and absorbing solar energy, and they move freely in liquid; they have already solved sticky problem and energy source problem. That is our motivation to research and develop micro robot which moves in liquid. In this report, we have proposed new concept of the robot using heat engine composed of gear and pulley and shape memory alloy actuator as its source of motion. We make 1cm3 sized proof-of-concept prototype of the heat engine to check its basic performance. We also discuss about possibility and applications of the in-liquid micro robot.

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We calculated the phonon mean free path by a spectral phonon gas model to understand the reduction of lattice thermal conductivities. The effects of anisotropy of bismuth telluride on heat conduction were considered in the model using the anisotropy of elastic stiffness. The phonon mean free paths were assumed to be cut off by nano-sized grains. As a result, the a-axis and c-axis cumulative lattice thermal conductivities of bismuth telluride are similar values in the cutoff phonon free path less than a few 100 nm. The result shows that the lattice thermal conductivity of nanostructured highly anisotropic materials with a-axis and c-axis can be evaluated by the spectral phonon gas model. Furthermore, we apply to design the nanostructured materials lattice thermal conductivities with micro and nano thermoelectric devices.

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We investigated strain and grain size effects on the thermal transport of nanocrystalline bismuth antimony telluride thin films using both experimental studies and modeling. The fabricated thin films exhibited the average grain sizes of 30 < d < 100 nm, and the strain of-0.8% < ε < -1.4% in the c-axis direction whereas that of a-b-axis direction was constant at 1.7%. The thermal conductivities were measured using a 3ω method at room temperature. We calculated the lattice thermal conductivity using a simplified phonon transport model that accounts for the strain effect based on Christoffel equation and Lennard-Jones potential, and the grain size effect based on the full distribution of mean free paths. The theoretical calculation was largely in good agreement with our experimental results, and the detailed results will be discussed in the Symposium.

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We performed the chemical mechanical polishing (CMP) process simulations of GaN(0001) by a SiO_2 cluster in aqueous NaOH and H_2O_2 solution. In aqueous NaOH solution, OH" ions adsorbed on the Ga-top site of the GaN surface. In aqueous H_2O_2 solution, OH radicals adsorbed on the hollow site of the GaN surface and weakened the Ga-N back-bond. Therefore, we suggest that the OH radical is effective for GaN-CMP as compared with the OH ion. However, we did not observe the subsequent chemical reactions and the polishing process of the GaN surface in both environments. We performed the CMP process simulation of GaN(0001) by a SiO_2 cluster with many OH radicals produced by a catalyst. After the OH radicals occupied all the hollow sites of the GaN surface, and another OH radical attacked a Ga atom of GaN surface, we observed the diffusion of the OH species adsorbed on the GaN surface into the GaN bulk and generation of gallium oxide and N_2 molecules.

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In order to examine tribological behavior of polymer brush, we have constructed a mesoscale particle model of a polymer brush system, based on a Brownian dynamics scheme. The polymer model consists of coarse-grained beads connected with harmonic springs. The Lennard-Jones type interaction is assumed between beads; random forces and hydrodynamic frictions proportional to the relative velocity are also taken into account. With this model, we have executed a series of molecular dynamics simulation to investigate the polymer behaviors and total momentum transport between two brush plates.

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Surface Acoustic Wave (SAW) motor is an actuator driven by friction force, in which larger driving force is generally required. To reply such requirement, larger driving area is expected theoretically. On the other hand, driving force of the SAW motor decreases by adhesion of wear particles at the at the contact interface. In this study, larger driving force is realized with larger driving area by introducing surface texture and hard coating such as DLC and W-DLC for controlling behavior of wear particles.

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This paper reports on development of high vacuum flash evaporation equipment for continuous deposition of thick TiNiCu shape memory alloy (SMA) film. A pellet supply unit with load-lock chamber was separated from a main chamber of flash evaporation equipment. The pellet supply unit enabled to supply the source pellet as the main chamber is kept under high vacuum, resulting in prevention of SMA film oxidation while vacuum chamber opening for evaporation source supplying. The developed flash evaporation equipment was able to recover its high vacuum near to base pressure within 20 min after source pellets are added in the load-lock chamber. TiNiCu film flash-evaporated in this equipment showed appropriate shape recovery deformation at about 60℃. Composition of the film was Ti-53.2 at.% Ni-1.5 at.% Cu.

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Si micro-elecro-mechanicl-systems (MEMS) cantilevers were fabricated, on which Fe_<60>Pd_<40>, Fe_<86>Ga_<14> and Ni magnetostrictive films sputtered with various thicknesses. Dependence of film thickness (0.4-4.0μm) on crystal structure, film stress and magnetostriction was evaluated in detail, hi all magnetostrictive films, the crystalline structures had no dependence on the film thickness. The films were highly crystalline orientated. The FeGa/ Si, FePd/ Si and Ni/ Si cantilevers were initially deflected to 60 μm, 150μm and 150μm, respectively, due to the film stress. The FePd film had larger magnetstriction than the FeGa and Ni films. Magnetostrictions of 1μm, 0.4μm and 2μm FePd film were 60ppm, 50ppm and 50ppm, respectively. However, the magnetostriction decreased in 4μm-thickness, indicating that the optimal film thickness exists for generation of magnetostriction, hi the case of FeGa films, small magnetostriction of about 10ppm was observed in 4μm thick film. In the case of Ni films, magnetostrictions were about -20ppm in all thicknesses.

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In embryology, researchers conduct a screening of a monoclonal antibody for identifying specific protein, but the process takes long time by conventional techniques. In this study, we propose a microfluidic device which is capable to expose multi-embryos to different reagents each at a time. The device has 16 inlets and reaction chambers, and their reagents can be flowed to one outlet by a syringe pump. An immunostaining process was carried out to evaluate a function of the device. As a result, it was confirmed that the reaction time could be shortened, and volume of reagents could be reduced in comparison with conventional methods.

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Nano porous polyethersulfone (PES) membrane is a competent material for nanofiltration such as purification, fractionation and dialysis. We have ever been developing micro hemodialysis system containing this PES membrane. However, when blood was used in this dialysis system for long time, platelets adhesion occurred on the surface of membrane and its performance degraded. In this work, we coated fluorinated diamond-like carbon (F-DLC) on PES membrane to modify its surface. We investigated anticoagulant F-DLC/PES membranes with a micro fluidic device and experimentally found that the amount of cells attached to the surface thoroughly reduced by coating F-DLC. We also conducted long-term experiments for 1 week and the performance was found to deteriorate because of fouling without coating F-DLC.

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We have succeeded in protein crystallization and processing by electrically-induced bubble. The dispensed directional mono-dispersed micro-bubbles whose air-liquid interface tends to combine the ambient molecules due to by their stiction force on the surface of micro-bubbles. Electrically-induced bubble enables to generate mono-dispersed micro-bubbles by the electrolysis and local heat, and their generation speed was 30.8 kHz. These characteristics enable to agglomerate the protein molecule which brings to successful protein crystallization in the solution with low concentration. The rate of protein crystal-nucleation by electrically-induced mono-dispersed micro-bubble was much higher than that of control condition

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We present a simulation study on network formations of microtubules and kinesin-streptavidin complexes confined in liposomes. The simulations were performed with a Brownian dynamics simulation. The simulations showed that microtubules formed aster-like networks pointing their plus ends toward the centers of the liposomes they were confined. During the formations, by moving towards the microtubule plus ends, kinesin-streptavidin complexes served as moving crossbridges between two microtubules. Effects of the density of kinesin-streptavidin complexes were also discussed.

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In recent years, stimulus response polymer gels that are respond to temperature, pH, and electric field have been studied. Therefore, these gels are expected for artificial muscles, micro pumps, and medical devices. We focus attention on the PNIPAAm gel (Poly N isopropylacrylamide), which is temperature sensitive polymer. The PNIPAAm gels exhibit swelling and contraction reversibly by changing temperature. However, the gel shows the very slow response to an exogenous stimulus. In this study, we succeeded in improving the performance of the response of the PNIPAAm gel by designing the fibrous structure inside the gel by using the Electro Spinning method.

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The line-of-sight detection system has promising applications in various fields, such as human-computer interaction and marketing. In our previous work, we proposed wearable line-of-sight detection system using micro-fabricated transparent optical sensor on eyeglass and successfully demonstrated line-of-sight detection using the proposed system. However, it required careful calibration with respect to each user and line-of-sight detection even failed for some subjects. We consider that characteristics of the subjects that include shapes of eyes, heights of noses, etc. are the crucial parameters. We investigated which factors are dominant on the reaction rate and the reaction speed of the cells to achieve a practical use.

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Our group demonstrated a MEMS-based tactile display that can control the created surface textures by the driving frequency and voltage of the actuators. It can create rough or smooth surfaces, but so far it is not successful to control the characteristics of the created surfaces that include roughness, hardness, etc. This paper attempted to obtain the actuation patterns of MEMS tactile display to create a designated surface textures. In order to do so, we slide the surface on the tactile display, consisting of an array of piezoelectric actuators, and detect the generated voltages by the actuators. The ultimate goal of this work is to code the surface textures into frequency and voltage.

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