Semiconducting p-FeSi_2 is one of the promising candidates for TE materials due to its large Seebeck coefficient, abundant source, low cost and high oxidation resistance. However, due to its low electrical conductivity, thermoelectric performance of β-FeSi_2 is limited. Precipitation of Si within β-FeSi_2 is one of promising method for improving transport properties. In the present study, an attempt to clarify the effects of precipitated Si on electrical properties of β-FeSi_2 was carried out by altering the heat treatment condition. According to the microstructure analysis, clear difference in the texture among the samples prepared with different cooling condition was observed. However, thermoelectric performance of the Si precipitated sample was rather low compared to non-doped β-FeSi_2. This is possibly due to the existence of metallic phase within quenched samples, which causes large value of electrical conductivity but low value of Seebeck coefficient. And a large amount of cracks was existed. Doping elements for both β-FeSi_2 and precipitated Si are necessary to improve thermoelectric properties, while fine microstructure of β-FeSi_2 - Si composite was successfully obtained in the present study.

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Conducting polymers, such as polyaniline, polypyrrole, and polythiophene, have attracted the attention of researchers investigating suitable materials for use in thermoelectric applications involving environmental energy conversion, because conducting polymers are inexpensive, lightweight, and relatively harmless materials. Moreover, conducting polymers have several attractive features for use as thermoelectric materials because of the thermal conductivity much lower than that for inorganic thermoelectric materials as well as the relatively high electrical conductivity. We investigated the thermoelectric properties for poly (3,4-ethylenedioxythiophene)(PEDOT):polystyrene sulphonic acid (PSS) films and the effect of addition of tetrakis(dimethylamino)ethylene(TDAE) on thermoelectric properties of PEDOT:PSS films. We found that the dimensionless thermoelectric figure of merit ZT of PEDOT:PSS film was enhanced by TDAE addition.

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Friction of silicon carbide (SiC) films under water environment shows a low friction coefficient experimentally. Understanding of the mechanism is essential to improve friction characteristics of the SiC films. However, it is difficult to directly obtain atomic-scale dynamics with chemical reactions by experiments. In this study, our purpose is to reveal the chemical reactions of the SiC surface under water lubrication by our first-principles molecular dynamics (FPMD) and tight-binding quantum chemical molecular dynamics (TB-QCMD) methods. First, we performed the simulation of SiC sliding in water by our FPMD method and then Si-OH and C-H bonds were generated on the surface. Next, we also simulated the larger model of SiC in water environment by our TB-QCMD method. Then, the generation of Si-O-Si bonds and the growth of Si-O-Si bond chains were observed. We suggest that this growth relates to the low friction property of the SiC surface.

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Molecular dynamics simulations were carried out to investigate friction on the atomistic scale. A simplified model consisting of substrate and slider which is pulled by a spring connected to a tractor was applied. As a result, stick-slip phenomenon was observed. Various contact conditions were investigated, and their effect on the frictional behavior was tested. When the contact between the slider and substrate is tight, stick-slip tends to occur, while the contact is loose or there is a misfit between the crystal arrangement, smooth kinetic friction is observed. The sliding velocity also affects the behavior; as the sliding is faster, smooth friction is observed. On the contrary, stick-slip is observed more often when the sliding motion is slower.

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We examined the effect of surface modification to reduce friction. Silen-coupling treatment is powerful tool for surface modification. This was influenced by oxidation state of material. We show surface modification effect on SiO_2 and Au. To make sure of silane-coupling, we used X-ray photoelectron spectroscopy and contact angle measurement. We evaluated friction by atomic force microscope. We observed that SiO_2 substrate had higher coverage of silane than Au substrate, the long side chain of silane was more effective than the short side chain to reduce friction, and the methyl group was better than the amino group for decreasing frictional force. Surface free energy directly affects friction force. The control of surface free energy is important to reduce friction.

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The mechanical seal which shows low and stable friction under blood sealing condition is strongly required for next-generation a left ventricular assist device. In addition, stability for wide load range is also required due to its in-vivo situation. In this study, we found that the mechanical seal consists of self-mated SiC shows low allowable load compared to material combination of SiC/C due to smoothness of sealing surfaces. In order to achieve low friction and high allowable load under blood sealing condition, we conducted pre-sliding in water and micro/nano scaled surface texture and these resulted in desired friction properties under blood sealing condition.

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This paper reports on the combinatorial characterization method of magnetostrictive alloy thin film using a MEMS cantilever array. MEMS cantilevers having a bilayer structure of Fe-Pd (4 μm) / Si (10 μm) were fabricated from an SOI substrate. The Fe-Pd film was sputtered with separate target to obtain a composition distributed film on the cantilever array in a substrate above the target. In the sputtering with the separate target, about 10% composition variation was obtained in the deposition area. Magneto-strictive effect was evaluated by deflection of each cantilever in the composition range of 69〜81 at.% Fe content. Cantilever deflection caused magneto-strictive effect was confirmed when magnetic flux of 100 gauss was applied. No significant difference of magneto-striction was observed in the composition range. Maximum magneto-striction in the cantilevers was about 13 ppm.

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As a result of the experiments using the endotoxin test kit commercially available, it was found that the coagulation change appears more quickly endotoxin concentration is higher. So, a method for measurement of the coagulation reaction to detect the difference in flow velocity of the micro flow channel due to coagulation was proposed. The specification required for endotoxin test analysis chip design was given experimentally.

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This paper reports the local chemical reaction in the counter flow diffusion reactor investigated by using luminol chemiluminescenee (CL). The local chemical reaction is important phenomena to control the performance of the micro-fluid device. The chemical reaction rate can be estimated by applying the luminol CL reaction at an interface between two liquids in the microchannel. However, the chemical reaction rate constant and the mass diffusivity are necessary to estimate the local chemical reaction rate quantitatively. In this study, the local chemical reaction the counter flow channel was investigated to determine the chemical reaction rate constant.

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We have successfully produced mono-dispersed micro-scale plasma balls in microfluidic chip under atmospheric pressure, and which can be transported to the downstream of the chip. The plasma produced has characteristics of low temperature and which was generated by dielectric barrier discharge for biomedical applications. The discretized plasma phases in microfluidic chip contribute to simple digital control and high accuracy irradiation with limited collateral damage area due to the plasma. A few hundred meter transportation distance has been confirmed for the preliminary experiment. The radical reactivity was also confirmed by collecting the solution from the outlet of microchannel. This technique can be widely used in various applications such as therapeutic aims, biomedical processes and sterilization treatment.

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Motor proteins form a molecular complex with other proteins in vivo and generate various functions such as a sarcomere and flagellar. And so, the development of micro device that incorporates these functions is expected. In this study, we focused on the oscillatory motion of flagellar axoneme, among the biological motion driven by motor proteins. Therefore we aim to be used as a power of the micro device the oscillatory motion. Currently, we attempt to construct a "sperm type" micro device having a structure of the oscillatory motion of the flagellar axoneme by the bottom-up approach to growing artificial flagellum by the self-assembly ability of protein from the microsphere.

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This paper discusses an approach to prepare bilayer lipid membrane (BLM) using droplet contact method at micro-scale. To substantialize this method, Split-and-Contact Device (SCD) which makes the BLM by mechanical motion was developed. A method using BLM are known as a powerful tool for the ion channel analysis or membrane protein study. Micro SCD is a device that applied the SCD concept and miniaturized well opening length concept, result to micro-scale droplet interface region. When the droplets are split and joined together, the lipid monolayer surrounding them at the interval combine to form a robust lipid bilayer. The α-hemolysin (αHL) that acts as pores, incorporate into the lipid bilayer, allows the ionic currents to be flow across lipid bilayer, and measured. Here, we present three different well opening size that are 500, 300 and 150 μrn. This system was able to fabricate stable BLM and the low current noise recordings of aHL channel were achieves using this system.

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This paper demonstrates a tactile display to present spatial distribution of stiffness using magnetorheological (MR) fluid. MR fluid reacts changes its mechanical property when magnetic field is applied to MR fluid. The display encapsulates MR fluid with flexible PDMS membranes and can create a hard spot in soft surfaces. We investigated the mechanical properties of the manufactured display and confirmed that stiffness of tumor tissue was created on the display. We compared them to human subjects' tactile sensations and confirmed sizes of hard spot that subjects answered depend on and tactile sensation on their fingertip and their perception of length. The ultimate goal of our work is to enable palpation in telesurgery and diagnosis using an endoscope.

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This paper reports creation of virtual surface textures using a MEMS tactile display. The display consist large-displacement MEMS actuators with hydraulic amplification mechanisms. By controlling the displacement, the vibration frequency, and actuator driving, the display could generate the tactile feeling of various surface textures to a fingertip. In order to investigate the produced virtual tactile sensation, we prepared 18 samples, such as wood, urethane foam, and sandpapers, to compare. The subjects were requested to select one of these samples that had a texture most similar to the one produced by the display. We categorized the samples with respect to roughness and softness, and correlated the control of actuators to the selected samples and thus, roughness and softness. We used information content to analyze the results and experimentally found that displacement of actuators had strong correlation with the roughness and the display presented hard surfaces except when apparent motion was generated.

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Tactile displays are promising devices as a human interface technology. However it is difficult to quantitatively evaluate the stimuli that the tactile display provides to the subject. This is because there are many parameters that affect the sense of touch, such as roughness, hardness, temperature and so forth. In this paper, we propose a quantitative evaluation method using haptic samples fabricated by Micro-Electro-Mechanical-System technology. As the samples, we prepared polydimethylsiloxane (PDMS) samples which have a parameter only in hardness. By using these samples, the effect of hardness on the sense of touch is investigated. The result showed that the softer the samples were, the smoother the feelings of touch were.

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Flexible conductive composite materials have a great potential to be applied to MEMS sensors and transducers. The composite materials' electrical properties can vary from the property of an insulator to a good conductor according to the material and design. In this study, we evaluated the mechanical and electrical properties by varying the type of the filler, the type of the insulating flexible material, and the ratio of the filler to the insulating material. We used two types of polydimethylsiloxane (PDMS) as the insulating material, and two types of filler, i.e. silver powder and multi-walled carbon nanotubes (MWCNTs). The mechanical and electrical properties of the elastomer composites varied according to the type of each elements and the ratio of the insulating material to the filler. The varying characteristics make the composites suitable to be used in various applications.

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In this paper, we present the design, fabrication and evaluation of a resonant micro-mirror able to compensate resonant frequency shift due to a non-liner spring effect. The spring constant in torsional mode can be varied by a stress generated using an integrated electrothermal tuning actuator (tuner). The tuner can change the torsional spring supporting the mirror by 40% at a thermally induced compressive stress of 390 MPa. The resonant frequency shift is suppressed from 1.5% to 0.05% at an optical scanning angle of 40° by optimal compensation of torsional spring.

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This paper reports the effect of ppb-level non-ionic surfactant, Triton-X-100, on the etching of Si {100} plane in 5wt% or 48wt% KOH solution. Si {100} etching rate decreased dramatically when 10 ppb of Triton was added to 5wt% KOH solution. In pure 5wt% KOH solution, micro-pyramids appeared on the Si etched surface. However, in 5wt%KOH with addition of ppb-level of Triton, the etched surface became mirror-like. On the other hand, Si {100} etching rate did not changed when 10 ppb to 0.1 wt% of Triton was added to 48wt% KOH solution.

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We developed a single microheater combined quartz crystal microbalance array for thermal desorption spectroscopy. In this study, new designs of the microheater were fabricated and frequency stability of fabricated sensor was compared between the new designs of the microheater. In a design of the microheater, the frequency stability (3 σ) calculated from the frequency change for 60 sec was 1.4 Hz when the sensor was heated to a temperature of 140 degrees Celsius. The design was effective to improve the frequency stability under heating. In addition, identification between methanol and ethanol was carried out by using the sensor.

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Thermal analysis and calorimetery have been widely used as a basic technique to characterize the thermophysical properties of materials. In our previous study on the cantilever-type MEMS calorimeter, multi-mode thermal analysis and resonance mass measurement using the mechanical resonance of the cantilever for micro- to nano-gram level sample were demonstrated. The objectives of this study were to improve quantitativity in carorimetry and mass measurement with the developed MEMS calorimeter. In order to investigate the effect of a position of the sample on DTA and resonance mass measurement (RMM), DTA and RMM experiment as a function of a position of a sample on the cantilever are performed with a micro-gram level alloy of cupper and tin. In addition here we described a previous calibration using a reference sample to compensate an effect of sample position on RMM.

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Particles ranging from several nanometer to several hundred micrometer in diameter exist in the atmosphere, and they are called suspended particulate matter, SPM. And recent progress in nano technology increases the importance of removal of nano- and submicron-size SPM. We are trying to develop a humidity-swing air cleaning method. This method consecutively humidifies sample air with heating and dehumidifies it with cooling. We tried to increase removal ratio. The experimental results showed that the survival ratio of the total SPM decreases with difference of absolute humidity. This indicated that removal ratio is proportional to the difference of absolute humidity and total SPM concentration. The maximum removal ratio was 95% at the condition of air flow rate of 25 l/min and difference of absolute humidity of 0.2. Removal ratio improved from 80% to 95%.

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Biohybrid systems, formed by combining biological cells and artificial components has a potential to resolve the current technical limits of traditional microactuators. We demonstrate fabrication of a movable microstructure, which can be coupled to Vorticella convallaria. Fabrication conditions by microfluidic in situ photolithography techniques were characterized. Movable components were fabricated in a PDMS micro channel with a shaft. A movable component was rotated centering on a shaft by a unidirectional flow. A device for trapping a cell was fabricated to combine V. convallaria and polymerized microstructures. Our developed method provides one strategy to integrate bioactuators with artificial structures in microsystems.

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A fixture to prevent buckling of microneedle biomimicking mosquito's labium is proposed. This fixture is a flexible elastomer sheet which is set on the surface of human skin. While the needle is passing inside the sheet, its lateral movement is prevented thanks to the existence of sheet material. After the needle passes through the sheet and penetrates the skin, the buckling stress is theoretically 4.5 times increased from viewpoint of strength of materials, that are, 1) the hinged end is changed to the fixed end, and 2) the effective length of needle is reduced by the thickness of guide sheet. This effect was experimentally confirmed by using a sharpened tungsten needle and a PDMS sheet as the fixture.

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We propose a rounded knife-edge structure having a large surface area to increase the dosage amount in the trans-dermal drug delivery system. We fabricated a Si rounded knife-edge structure as the original master by anisotropic wet etching. We then replicated the same shape with biodegradable hyaluronic acid-based material by a molding process. We evaluated the penetration performance of the fabricated knife-edged structures into an artificial skin of a silicone rubber sheet and confirmed that both the Si and biodegradable knife-edged structures successfully penetrated the sheet with an applied load of 180 g. We also fabricated an arrayed biodegradable rounded knife-edged structure that successfully penetrated mouse skin.

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This paper experimentally investigate the shapes of micro-needle electrodes to effectively display tactile information by electrically stimulate tactile receptors. In our prior work, we revealed that a needle-type electrotactile display that penetrates through a stratum corneum of a finger skin can display tactile information at 20 times as low voltage as that with flat electrodes. We discovered that the needle-tip shapes greatly affected the performance of the display. When the tip radius is small, the large impedance of the electrodes results in high voltage to stimulate the receptors. On the contrary, when the tip is too large, the electrodes cannot penetrate through the corneum that has much higher impedance than dermis. In this work, we experimentally deduced the optimum shape of the needle tip using titanium micro-needles patterned by electrochemical etching. The needles can be readily applicable to efficient electrotactile displays.

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Recently practical micro/nano devices using nanomaterials such as nanoparticles and nanowires have been developed in various fields including nanophotonics and nanoelectronics. Manipulation of nanowires is indispensable for constructing the microdevices. Here we propose and experimentally demonstrate a novel method of three-dimensional optical manipulation of a metallic nanowire using an optical vortex. In our method, a metallic nanowire can be grasped by optical repulsive force and simultaneously rotated by total angular momentum of an optical vortex. In addition, the posture of a metallic nanowire can be horizontally or vertically fixed in any direction by high-speed switching of the helical phase shift of an optical vortex. The aligned nanowire can be translated to the desired position by moving the stage supporting a sample.

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This paper presents a novel and simple method of the particle sorting by optical force with large area irradiation which enables damageless handling with low energy density. Particle sorting in a microchannel is promising technology to be widely used in the field of chemical and medical analysis. However, a strongly focused irradiation of laser beam as in optical tweezers would yield serious damage to the device and sample due to the high energy density. Our alternative sorting system includes a microfluidic device with long channel in which particles flowing inside receive low energy light. Enough long retention distance of particle depending on its size is achieved in the downstream region of the device. We have successfully demonstrated our concept of the simple particle sorting system which could expand the use of the optical-based particle manipulation technique.

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A particle manipulation device using the dielectrophoretic (DEP) force is described in this study. The "rail-type" electrodes consist of three parallel electrodes attached to the bottom wall and the top wall connected to the electric ground. These electrodes can generate a DEP force distribution that captures the particles, the DEP force of which is "negative" (repulsion force), in the specific area located at the center of the electrodes and adjacent but with a certain distance to the bottom wall so that the particle will not attach to the wall. The particles can then be guided individually along the electrode. Using the "flip-type" electrode in combination with the rail-type electrodes the direction of the particle can be selected with high accuracy, reliability and response. Measurement using the high-speed camera was carried out to measure the motions of the particles and lymphocytes, and to evaluate the performance of the electrodes. The trajectories and the probability density functions of the particles at the inlet and outlet of the electrode region showed that by using these electrodes the particles can be guided accurately in the spanwise direction of the channel.

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Recently, the number of patient with food allergy is increasing, and the allergy symptoms are especially serious for babies and children. Our group is studying new diagnostic method for food allergy. This diagnosis is the examination of response to allergen for basophils by SPR Imaging. The diagnosis method is necessary to separate basophils from unnecessary cells. However, it has two problems; one is long operation time and the other is to need a lot of blood sample to keep certain amount of basophils. Therefore, we started to study new allergy analysis chip with highly efficient separation channel to reduce operation time and minimize sample volume.

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In this study, we challenged to construct an ameba-type molecular robot, which was changed its morphology using activity of motor protein trigged by calcium signal. An artificial kinesin which we designed, was formed tetramer complex by calcium ion signal and transformed the microtubule networks to aster or stress fiber-like structures. We tried to synthesize a droplet or liposome containing this microtubule networks as artificial cytoskeleton.

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We propose an innovative simple and smart microfluidic actuator, which is made of photoprocessible thermoresponsible gel, for the disposable biomedical application. The smart gel is called "Bioresist", and arbitraly micropatterns can be achieved by the standard photolithography technique. The actuator is actuated only by local heat control of microheater, and several microfluidic functions are achieved by its expansion/contracting motion. We would remark that the required voltage which can control the expanding/contracting motion is only about 1.5 V. Furthermore, proposed method is easy to integrate into microfluidic chip.

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This paper describes DNA logic gates with biological nanopores which are formed by membrane proteins constituted in lipid bilayer membranes (BLMs). BLMs as artificial membrane are formed in droplet-contact method (DCM). Split- and-contact method (SCM) is the system applied DCM. BLMs are simply and speedy formed in SCM. And we can use the rapture of BLMs as positive manner (ZAP) because SCM can allow ruptured BLMs to be re-formed many times. Biological molecules are translocated into the nanopores which are formed by aHL constituted in BLMs using SCM. We focus on DNA as one of the biological molecules. Single-strand DNA (ssDNA) is translocated into the nanopore, while disturbing the translocation of ions and Double-strand DNA (dsDNA) blocks the nanopore. In this study, we demonstrated DNA-OR gate and DNA-NOT gate as DNA logic gates in these system, SCM and the characteristic of DNA.

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This paper presents a concept of no-dialysate micro hemodialysis system, and discusses solute's diffusion coefficient and water permeability of the dialysis membrane. No-dialysate micro hemodialysis system allows miniaturization of the hemodialysis system, which is mandatory for our ultimate goal of implantable dialysis systems. Diffusion coefficient and water permeability of the dialysis membrane is a crucial parameter to determine the system performance. We highlighted nano and micro porosity of a poly-ether-sulfone (PES) membrane and developed water-permeable dialysis membrane. Proof-of-concept experiments of no-dialysate micro hemodialysis system were successfully conducted, and we found that the thickness of nano porous structure affected water permeability.

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Now, high sensitive, wide-measurement range, high-speed response and small size (as whole system) load sensors are desired in many fields, such as medical field, life support robots and industrial robots. Therefore, in this paper, we develop a compact load sensor using AT-cut quartz crystal resonator whose resonance frequency changes under external force, and features high sensitivity, a wide measurement range, high-speed response, and superior temperature and frequency stability. We design a quartz crystal resonator sensor to increase its sensitivity and to reduce the whole volume of the packaged sensor. We made the quartz crystal sensor and the sensitivity was increased from 574Hz/N to 896Hz/N and the volume was reduced from 423mm^3 to 226mm^3. We designed and fabricated a package of the sensor which has a mechanism of pre-loading of the quartz crystal sensor.

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Additives have a very important role in engines, molding process, printings and in a wide variety of engineering. Some additives form an adsorbed layer on a solid surface. These layers enhance protection of the surface and/or reduce friction force. Therefore it is important to know a formation process of it and its physical properties. Quartz crystal microbalance (QCM) has been known as a sensitive mass-measuring device. And, QCM has been used to monitor the physical properties of thin liquid film on its surface. The resonant frequency of the quartz crystal is dependent on the viscosity and the density of the liquid film. By using this relation, QCM allows one to evaluate viscoelastic properties of adsorbed layer on a surface. In this work, QCM was applied to study the formation process of the adsorbed layers by additives and evaluate its physical properties. Especially, we focused on the contact area and its position of a sample droplet on an electrode surface of QCM.

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In recent magnetic storage systems, the spacing between the flying head and the disk has been dramatically decreased to less than 5 nm for realizing ultra-high density recording. Liquid lubricant on the disk is transferred to the flying head slider (pick-up) due to the intermittent contact between the slider and the disk or due to the condensation of the lubricant vapor. The small amount of the lubricant picked-up to the flying head slider will affect the flying characteristics and the read/write performance. In this study, characteristics of liquid transfer due to the breakage of a liquid meniscus bridge are investigated experimentally and theoretically. In particular, the effects of surface roughness on liquid transfer characteristics have been investigated.

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A novel infrared (IR)-to-visible transducer thin film array made of Eu(TTA)_3-based temperature sensitive paint (TSP) for a thermal imaging device is proposed. A micro-fabricated thermal isolation structure of the TSP, of which the luminescence intensity changes with the temperature, is heated by incident IR light. Therefore, the power of IR light is converted to the intensity of luminescence. This optical read-out method does not need electric wiring for operation, which can minimize the heat loss. The temperature coefficient of the prepared TSP was about -1.58%/K, and the IR emitted from the observation object was successfully detected. The sensitivity of the device was about -0.01 %/K.

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This paper presents an experimental platform to explore effective ambient intelligence systems using a MEMS-based wearable eye-tracking system and tactile display. Ambient intelligence, which allows us to receive useful information on site and at real time from the surrounding environment, requires a method to let the users be aware of the information. Given that our vision and hearing is heavily used, we consider that utilizing of tactile sensation is most effective. In our experiments, tactile information was provided to a subject by a MEMS tactile display that has an array of MEMS actuators and his response was detected by a wearable eye-tracking system that used micro-fabricated dye-sensitized photovoltaic cells on eyeglasses to detect the movement of his eye. The proposed platform is readily applicable to develop effective ambient intelligence systems and other information communication technologies (ICT).

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The line-of-sight (LOS) detection system has various applications, such as in the field of health and welfare, human-computer interaction, and safety and security. In this paper, we demonstrate a LOS detection system which has micro-fabricated transparent optical sensors on eyeglasses and its applications. We achieved the detection accuracy of 1.5 ° in the view angle. The system also was capable of detecting user's eye blink. Then, we demonstrated applications for information communication technology using the user's LOS detected by the developed system such as eye-controlled human interface.

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Miniaturization, simplification and high functionality are very important for chemical analysis systems. At present, We have already proposed a concept of plug & flow platform for miniaturized chemical analysis system that can be quickly modified fluid circuit according to the analysis of a wide variety of items. However, as the systems are smaller and simpler, they might be sensitive to the circumstance's fluctuation and deteriorate the analytical performance. In order to keep the performance, the algorithm to estimate the working condition and to predict initial sample concentration by using model-based simulation with Kalman filter and the remote monitoring method based on it was proposed. Feasibility was checked by giving the observation data. The estimated result traces well the original concentration.

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In this study, we report on the blood pressure measurement device for reducing a cross talk based on artery tonometry method. Our device is the convex array sensor which has three pressure sensors and slots between sensors. The size of our device and convex parts are 30×30×8.0 mm^3 and 3.0×30×2.0 mm^3, respectively. We measure cross talks of the convex array sensor and the plane array sensor. By using the convex array sensor, the cross talk was reduced from 45% to 30%. We change the size of convex parts in order to reduce the cross talk further. When the size of convex part is 3.0×30×1.0 mm^3, the cross talk was reduced from 30% to 18%. Since deformation where the pressure is applied is hardly transmitted to the other sensors, the cross talk was reduced by the convex array sensor.

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Cathodoluminescence (CL) is light emission from the materials excited by accelerated electron beam, and CL microscopy has both molecular specificity and nanometer-order spatial resolution. Because of electron beam excitation the spatial resolution reaches about 10 nm. CL microscopy for biological specimens was performed using cathodoluminescence (CL) of Y_2O_3:Eu, Zn nanophosphors, which have high CL intensity due to the incorporation of Zn. Y_2O_3:Eu, Zn nanophosphors in HeLa cells were also imaged with 254 nm. In addition, we propose a new correlative imaging method using upconversion (UC) fluorescence and cathodoluminescence. The results suggest that correlative microscopy using CL, secondary electrons and fluorescence imaging could enable multi-scale investigation of molecular localization from the nanoscale to the microscale.

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In order to introduce novel atomic force microscope (AFM) applications in cellular function analysis, we have been developing an AFM probe, named "bioprobe", which is integrated with a hollow silicon dioxide (SiO_2) microneedle. In this paper, a bioprobe fully integrated a microchannel was successfully fabricated by our developed process. In order to reduce cell damage, we propose a vibration-assisted insertion method for penetrating a cell membrane. The probability of penetrating the cell membrane at indentation depths less than 500 nm with mechanical oscillation (73%) was significantly higher than that without oscillation (22%). Moreover, we demonstrate an extremely small amount of fluorescently labeled DNA can be ejected electrokinetically though a nanoneedle tip.

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Embryonic stem (ES) cells are one of the principle focuses in biology because of their pluripotency and potential therapeutic applications. Although it is known that soluble factors affect differentiation of ES cells, little is known about the influence of mechanical stimulus on the differentiation of ES cells. Here we investigate the influence of mechanical stimuli on mRNA expression of mouse ES cell during the differentiation process. Without a mechanical stimulus, mRNA levels of pluripotency markers, Oct3/4 and Klf4 decreased and primitive ectoderm marker, Lefty1 mRNA level increased, suggesting that mouse ES cells might differentiate into primitive ectoderm. With a mechanical stimulus, Klf4 and Lefty1 mRNA levels decreased. We speculate that progress of differentiation into primitive ectoderm can be inhibited by a mechanical stimulus.

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The spin Seebeck effect refers to the conversion of a heat current into a spin voltage in a ferromagnet/paramagnet junction. Since the spin Seebeck effect appears not only in metals and semiconductors but also in magnetic insulators, it enables the construction of "insulator-based thermoelectric generators" in combination with the inverse spin Hall effect, which would be impossible if only conventional thermoelectric technology were used. In this paper, we briefly report on the experimental observation of the spin Seebeck effect in magnetic insulator/metal junctions and discuss the potential for novel thermoelectric technologies based on spin currents.

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Higher Manganese Silicides (HMS) have been revealed as composite crystals consisting of two tetragonal subsystems of [Mn] and [Si] with an irrational c-axis ratio γ = c_<Mn>/c_<Si> 〜 1.73. The structure formula is thus expressed as MnSi_γ. Due to a significant positional modulation of Si atoms while maintaining the carrier conduction paths of Mn atoms, the concept of phonon glass and electron crystal (PGEC) is actually realized in the present unique crystal structure. Atomic-, unit cell- and micron-scale modulation can be applied to the HMS-based thermoelectric materials to minimize the lattice thermal conductivity together with to optimize the electronic structure, and hence maximize the dimensionless figure-of-merit.

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Air-suspended Si nanowires with various widths and a phononic crystal nanostructure with a period of 300 nm were fabricated on an SOI wafer by electron beam lithography and their thermal conductivities were measured at room temperature. We observed lower thermal conductivities for narrower nanowires. The reduction of the thermal conductivities mainly stems from the increase of the surface scattering rate. On the other hand, in the phononic crystal nanostructure, we observed lower thermal conductivity compared with a nanowire with a width equal to the narrowest part of the PnC structure. Therefore, the phononic effect may also play some role in heat transfer in the PnC structure in addition to the increase of the surface scattering.

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In this study, we have performed molecular dynamics simulations based on the interatomic force constants obtained from first principles to evaluate phonon transport across the PbTe/PbS interface. Thermal boundary conductance was obtained by two different methods: (1) Landauer formula with the phonon transmission function calculated from equilibrium molecular dynamics (EMD) and (2) direct nonequilibrium molecular dynamics (NEMD). The thermal boundary conductance of an atomically smooth PbTe/PbS interface calculated by the two methods agrees well, indicating the validity of the phonon transmission function calculation. Furthermore, we have considered the thermal boundary conductance at the PbTe/PbS interfaces with step roughness to study the influence of the interface structure. It is found that the roughness decreases the thermal boundary conductance by 50 %. The calculated phonon transmission function indicates that the steps reduce the phonon transmission in the entire frequency regime without significant mode selectivity. The analysis also suggests that the inelastic phonon scattering at the interface contributes to at least 15 % of the entire thermal boundary conductance.

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A micro dimple machining is studied to control the surface functions with the micro-scale structures on the solid surfaces. The micro dimples are machined in milling with the inclined ball end mill. When the feed rate of the tool is high enough that the removal areas of the edges do not overlap each other, periodical concave dimples are machined. A mechanistic model is presented to control the shape and the size of the dimples to be machined. The micro dimples were machined on a plate of fine-grained stainless steel to reduce burr formation. Then, the depth of the affected layer was measured in subsurface of the machining area. Finally, the contact angle on the dimple surface was measured to change wettability with the surface structure.

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The material for micro plastic forming is generally made by rolling, extrusion or drawing. So the material naturally has plastic anisotropy. For macro forming, plastic anisotropy mainly influences the shape of deformation, forming limit and forming load. But for micro forming, there are a few researches on the plastic anisotropy. In this paper, we investigate plastic anisotropy for the material of micro plastic forming. A small-cube compression test is useful to measure plastic anisotropy for the local area or the small material. By using this test, we measure the influence of plastic anisotropy on the deformation shape. Since the compression test is needed to consider friction between die and specimen, we also check the influence of friction and plastic anisotropy on the deformation shape.

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