Possible technique to generate the steady laser detonation wave is considered theoretically. This new kind of detonation wave can be sustained by irradiating a supersonic flow by the addition of small amounts of nano-size black-carbon particles. The supersonic flow is heated up to the subliming temperature of the added particles due to the heat convection from the particle to the ambient gas. When this heating technique is applied in a rocket engine, the specific impulse more than 900 sec is attainable.

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In this research, it was considered to utilize a robot to rearing the children's mind which tries to help others. We made a small robot which is able to be controlled apart for experiments. This robot was examined at a nursery school. In front of the children, we made a robot perform easy movement of opening and closing of a door. Children who looked at robot which was not be able to do these simple movement well, showed behavior and utterance trying to help the robot. From this result we could confirm a possibility of rearing child care mind by using a robot.

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This content is in a living environment that varies with deregulation of energy, a teaching practice reports that consider the information necessary to select the energy appropriately. Junior high school students, more or less knowledgeable about electricity. However, it is the present situation that there is no understanding regarding gas. In this study, by comparing the electricity and gas were investigated classes in order to acquire the power to select the appropriate energy. "With a better understanding of the liberalization of energy, based on the features of the energy to acquire the power to select the energy," the goal of the class is defined as, we examined the course content. In March 2015 to junior high school sophomore 85 people, was carried out of the 50 minutes lesson. Results of teaching practice, together with the interests increases in energy, in order to select their own energy and could be aware whether it is necessary to learn what the students themselves.

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We developed the sensor system and method by using wireless motion sensor (WMS) installing inertial and magnetic field sensors to obtain the trunk joint torque for the hitting action by the rugby-football player. This system consists of inertial and magnetic field sensors and force plate. We defined the 3D rigid link model of the rugby player, and constructed motion equations based on the Newton-Euler method. We measured the accelerations and angular velocities by using WMS sensors attached to upper body and lumber segments, and impact force by using force plate. The WMS and the force plate outputs were converted into the lumber-spine joint torque. The behavior of the lumber-spine joint torque for keeping the posture of the rugby player in the hitting action was expressed qualitatively.

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The purpose of this study were to measure the ground reaction force and torque of ball in service ball bound and to investigate the index for the performance of tennis serve. To perform these purposes, following results were performed; 1) The ground reaction force of the ball and the rotary torque when a serviced tennis ball bounced were measured using a force platform. 2) For one of this result, about 350N of ground reaction force toward vertical direction and 50Nm toward ball driving direction were confirmed. 3) Ground reaction force to the vertical direction will be the power of the service, and it may be the parameter to evaluate a service performance (without the unit) of no dimension until now. In addition, the rotary torque of the service driving direction is regarded as a parameter about the power of the service for the speed, too. Furthermore, y direction, the torque of the z direction are regarded as the index indicating the change (kinking) of the ball course, and these results can be hopeful to the general performance evaluation of the service performance. 4) It is thought to be important to construct the experiment setting which is near by the real tennis game condition in future.

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The purpose of this study was to measure the mechanical signal of ski-board and the physiological signals from human in parallel using a new date logger system. The ski board vibration, human EMQ ECG in parallel were measured when ski drove. As a result in this measurement, we confirmed that the vertical vibration of ski board over 200Hz in skiing, lateral vibration of the low level occurred with a ski turn synchronously and drop of the MPF in skiing.

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The purpose of this study was to develop the measure the sport-typed wheel-chair, which can drive straight by either one-handed or both-handed operation. To perform this purpose, the transmission axis that had joint mechanism to transmit driving force from one side wheel to other side wheel was developed. In this study, the structural reinforcement of this transmission axis was investigated. Furthermore, as an evaluation of the wheelchairs performance, the evaluation from human exercise was reexamined the evaluation.

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A large-eddy simulation of a coal gasification two-phase reacting flow on an entrained two-stage coal gasifier was performed to demonstrate the applicability of LES to this reacting field on the massively parallel computing on K computer. The CRIEPI's 2.4 tons/day research gasifier was targeted. Results show that the strong swirl flows are formed within the combutor of the gasifier. The large part of particles traveling in the combustor should be expected to be captured by the centrifugal force and the characteristics is essential to optimize the gaisifer's design and operating conditions. It is confirmed that the LES is a potentially powerful tool to predict the strong swirl reacting flows within the entrained flow gasifier.

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A direct numerical simulation (DNS) is applied to a laboratory scale pulverized coal jet flame. Pulverized coal particles are injected with primary air in the double stream burner and the effects of equivalent ratio in the primary stream on the coal jet flame are investigated. In the DNS, the number of grid is about 0.17 billion, and the coal particle motions are tracked by a Lagrangian approach. The results show that the gas temperature of the flame annularly formed downstream the burner increases as the equivalent ratio increases. While, the spatial distribution of the gas temperature inside the flame becomes uniform under the low equivalence ratio condition.

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A dynamic behavior analysis on CFRP-made jet-engine fan blade has been performed by using K-computer. The simulation aimed to model a bird strike event by using an SPH-FEM weak-coupling analysis, where a single finite element is assigned to each unidirectional CFRP prepreg layer in the thickness direction of the fan blade. As a fundamental study, we performed an impact analysis with about 3.5 million elements using 8192 cores. The massively parallel simulation realized a dynamic behavior analysis of the full-scale fan blade model under impact loading.

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We focus on parallel finite element analysis of a large-scale soil-structure model. In order to increase structural safety of a RC building embedded in the surrounding soil for an earthquake, it is important to predict transient responses and damages of the building accurately. As the first step, performances of parallel FEM are evaluated through static analyses of a soil-structure model which consists of solid and shell elements. In mis analysis, infinitesimal deformation theory is adopted, the materials are specified via the linear elastic model and constant body forces are given. An open-source parallel FEM software, FrontISTR, is utilized as the parallel FEM program. First, it is confirmed that the present solutions are in good agreement with solutions obtained by a commercial software in static analyses of the building model. Second, a mesh refinement technique is applied to the soil-structure model and different-scale models are generated by the mesh refinement. The parallelization efficiencies are 76.9% for 64 processes in parallel computing of 3,814,476-DOF model, 74.1% for 512 processes in 28,886,532-DOF model and 65.2% for 3,840 processes in 224,503,260-DOF model.

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The cardiovascular system (CVS) is a complex system in terms of complicated network and dynamic regulation, which usually corresponds with other systems, such as autonomic nervous system (ANS) and respiration system. This has led to numerous studies; however their focus is predominantly on CVS corresponding to either respiration rhythm change during exercise or baroreflex regulation. However, in order to maintain homeostasis, variety regulatory systems, including the respiration system and ANS, work as negative feedbacks to adjust the cardiac output and the arterial pressure in the CVS. In this study, we focus on the short-term regulation and aim to develop a novel mathematical model capable to evaluate the cardiovascular autonomic functions by proposing an integrative computational model of CVS and the ANS. The model is further extended to include the exercise-related regulatory mechanisms such as muscle pump function, resetting of the operating point of baroreflex regulations and central command. For simulation validation, the model is used to predict the hemodynamic response to the position change and the recovery from one-leg cycling in different positions. During position change the blood pressure will first drop at the set-point, then return to the stable level, while the heart rate will gradually increase until it reaches to the stable level. In the recovery from the one-leg exercise the blood pressure in supine and upright position are close. On the other hand, the difference of the heart rate is comparatively close during exercise, and has a more than 15% difference after the recovery in supine and upright position. Moreover all the results show reasonable agreement with experimental data. This study provides valuable information on dynamic regulation in CVS by coupling with ANS.

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Fontan procedure is a surgical palliation used to treat patients with congenital heart disease such as single ventricle. Fenestration, a small hole between the conduit and right atrium, is expected to reduce the postoperative morbidity. Several recent studies have reported its effectiveness and favorable shapes. However, there is still no evidence on how the fenestration location influences three-dimensional hemodynamics in Fontan procedure. In this study, we constructed a three-dimensional patient specific model with fenestration based on the medical images. The three dimensional blood flow in Fontan Circulation is treated as laminar flow and computed by solution to the Navier-Stokes equations; boundary conditions based on zero-dimensional hemodynamic model specified for Fontan procedure are imposed at inlets and outlets. Our results indicate that locating the Fenestration in the middle of extra-cardiac conduit is the most effective way in terms of cardiac outputs and pressures.

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Recently, the lattice Boltzmann method (LBM) that one of the numerical methods has been used computational hemodynamics, but this method is difficult to simulate in high pulsatile flow such as aorta because of a low computational stability. Consequently, this study aims at validation the regularized lattice Boltzmann method as a more stability than LBM in computational hemodynamics in high pulsatile flow. In this paper, as fundamental study, we simulate the incompressible pulsatile flow in a circular pipe, and compare result of RLBM with one of the normal LBM. In this simulation, we use the virtual flux method in order to create the circular pipe wall in Cartesian grid. As a result, we show that RLBM can capture the pulsatile flow field at the Reynolds number that is nearly twice as high as LBM's in the same grid and time resolution. In addition, RLBM's time accuracy is shown to match well with LBM's. Therefore, it is confirmed that high accuracy even in the unsteady simulation is kept.

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A method for coronary arterial dynamics computation with medical-image-based time-dependent anatomical models was introduced. One of the important components of that method is a curve-extraction technique from time-dependent medical images. The curve-extraction technique is based on minimizing the strain energy for a curved-beam representation of the artery, and from that the arterial model is constructed by associating time-averaged cross-sections to the points along the curve. Here we present a new method for arterial wall modeling from time-dependent medical images. We have developed a surface-extraction technique for obtaining the time-dependent anatomical model from the medical images. In this technique, the arterial surface geometry is extracted from the medical image by using a NURBS representation of the extracted surface, and the surfaces associated with different instants of the cardiac cycle all have a common parametric space. In this technique, a reference is constructed using NURBS. The NURBS representation of the surface becomes a target geometry in the strain-energy minimization, and the resulting equations are solved over the arterial surface. We apply the method to a human aorta, with 20 images per cardiac cycle.

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Epithelial tissue constitutes many kinds of organs of multicellular organisms. During morphogenesis, tissue deformation is driven by forces generated by cell activities such as cell proliferation, cell migration and apical constriction. Because shape of organs is accomplished appropriately by a series of tissue deformation, force generation at cell level can be controlled by a result of tissue shaping in a feedback manner. As such a mechanism, we suggest a function of modifying apical constriction in response to cell shape change by mechanosensitivity of alpha-catenin, leading to the feedback relationship between apical constriction and cell shape. In this study, we construct a mathematical model of the feedback relationship and investigate its role in formation of tissue shape. Simulation results suggest that the modification is based on the shapes of adjacent cells, and that the function maintains smooth surface on apical surface of epithelial tissue by averaging the cell shapes.

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Cardiopulmonary resuscitation (CPR) is an important first aid technique for life saving. Even though the experiments performed on domestic swine have demonstrated that the occluded airway could also promote the efficiency of CPR, the studies using animals also have been criticized for the differences of airway mechanics between human and animals. Furthermore, because the thorax deformation determines the mechanical environment and the deformation of the organs inside the chest, the pressing location on the thorax influences the efficiency of the CPR. Therefore, this study is focused on investigating the influence of the ventilation and the thorax deformation on blood perfusion in the heart during CPR. By introducing the porous hyperelastic material model for the lung and heart and connecting the preload and afterload circuits representing the circulatory systems, we reproduced the deformation of the heart and lung accompanied with the thorax deformation. The deformation results demonstrated that the sternum is the appropriate press part of the thorax during CPR. From the results of the pleural and the cardiac chamber pressure and the volume change of the heart, it is noted that the occluded airway system may promote the blood flow in the heart during CPR.

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Osteoarthritis of the hip occurs from an abnormality in the shape of a hip joint. During the progression of osteoarthritis, a fluid-filled cavity called "bone cyst" appears and enlarges in cancellous bone, which leads to fracture around the cyst in the bone tissue. Because osteoarthritis relates to the mechanical condition of the bone tissue, it is probably expected that the growth of a bone cyst progresses with bone remodeling. Elucidation of the growth process of a bone cyst is thus important for understanding the mechanism of osteoarthritis of the hip. In this study, we estimated relationship between changes in wall thickness of bone cyst and growth of bone cyst by using our bone remodeling simulation method. As a result, we found difference of ratio of voids around bone cyst which leads to increase bone cyst, depending on the thickness of the cyst wall between the remodeled models. The voids surrounding bone cyst in the model having thin cyst wall was large, while the voids in the model having thick cyst wall was small. These results suggest that bone cyst grows due to increase of voids by bone resorption and growth speed of the cyst changes depending on the thickness of the cyst wall.

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Through bone remodeling, bone remodels its structure to functionally adapt to its mechanical environment. Bone cells produce signaling molecules activated by mechanical stimuli. It is considered that signaling molecules regulate bone remodeling. RANK/RANKL/OPG system is known as one of signaling systems. RANKL promotes osteoclastogenesis by binding to RANK, while OPG acts as a decoy receptor by binding to RANKL. In this study, we proposed mathematical models of trabecular bone remodeling combining mechanosensing and RANK/RANKL/OPG system, and conducted computational simulation. Focusing on the active bone remodeling area, we discussed the influence of the balance between RANKL and OPG expression rates on the functional adaptation capacity of trabeculae. We found that, under the condition where RANKL and OPG expressions balance each other, the active remodeling area is larger when both of the rates are higher.

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Tendon is known to remodel its structure and alter mechanical properties in response to changes in its mechanical environment. Tendon cells, tenocytes, are thought to play significant roles in tendon tissue remodelling, by responding to mechanical stress. Like other adherent cells, tenocytes exert traction forces to their substrate when the cells attach to the substrate. Cell traction forces are thought to reflect the level of intracellular tension generated in actin cytoskeletons. It has been shown that intracellular tension level is a regulatory factor of tenocyte catabolism. Accordingly, the present study hypothesized that tenocyte response to interleukin-1β is dependent on the level of intracellular tension. Tenocytes, isolated from rabbit Achilles tendons, were seeded microfabricated, elastic micropillar substrates, and were subjected to the treatment of IL-1β at four different concentrations. It was demonstrated that tenocyte traction force level was dependent on the elastic modulus of micropillar substrates. In addition, cells on softer substrates were more prone to the stimulation of the catabolic agent, exhibiting a greater change in cell morphology. These results suggest that tenocytes with a low level of intracellular tension, which implies that the cells are catabolic, are stimulated by catabolic/inflammatory agents and further enhance their catabolism.

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Irreversible electroporation (IRE) is a minimally invasive method for tumor treatment. It is based on the irreversible perforation of the plasma membrane which is induced by application of intensive electric pulses. However, effects of pulse parameters on cell mortality are not fully understood. In this study, we therefore examined the effects of the applied voltage (1-2 kV/cm) and repetition (15-150 times) on cell mortality after pulse application. Additionally, we investigated the impact of osmotic pressure on reduction of the required voltage for cell breakdown. Electroporation experiments using cuvette electrodes showed that dead cells increased as a function of voltage and repetition, which could be fitted by the Fermi distribution function. The cell mortality also increased in hypotonic medium that is probably attributed to cell swelling. These findings suggest that the higher pulse repetition and lower osmotic pressure are effective to raise cell mortality under the constant applied voltage.

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Cellular contractile forces are crucial to biological researches. Therefore, a number of cellular contractile force evaluation techniques have been proposed. In contrast to extensive researches on the effect of exogenous forces such as tensile stretch and fluid shear stress, there is less work on how endogenous contractile forces are generated within cells under various conditions. This situation may be partly attributable to the lack of experimental techniques for evaluating cellular contractile forces. One of the most popular techniques is traction force microscopy that employs fluorescent microbeads embedded within hydrogels on which cells are plated. Contractile forces of the cell are estimated from the displacement of the fluorescent beads and the physical properties of the hydrogel. This technique requires complicated image correlation analyses and sophisticated skills to perform the experiments. Hence it is not practical to use that technique in large-scale screening. We have developed an alternative that allows traction force visualization for individual cells with relatively easier approaches.

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Under electric field non-contact stirring technique (E.N.S.) showed antigen-antibody reaction time in an immunohistochemical staining can be shortened from 90 minutes of conventional method to 10 minutes. In this study, E.N.S. examined the mechanism which makes antigen-antibody reaction of an immunohistochemical staining quicken. As a result, we obtained that it has the mechanism which a reaction time of an immunohistochemical staining is shorten because antigens and antibodies improve to increase the frequencies of contact, and further antibodies disperse and becomes easy to react to antigens under E.N.S. compared with conventional method.

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Osteocytes are believed to act as mechanosensory cells in mechanically adaptive bone remodeling. The cell body of osteocytes has various morphology depending on the types of bone, surrounding mechanical environment and degree of maturation. The difference in osteocyte morphology will significantly affect the mechanosensitivity of the cells. In this study, we aim at identifying the relationship between the maturation and morphology of osteocytes within tissue by the morphometry of osteocytes based on technique of fluorescence imaging. Using parietal bone of a mouse, we labeled the newly formed bone by calcein to visualize the maturation stage of osteocytes. Furthermore, we fluorescently stained actin cytoskeleton in osteocytes and measured the area and aspect ratio of individual cell body. As a result, calcein-labeled bone clearly showed the process of bone formation, therefore enabled us to estimate the degree of osteocyte maturation. As osteocytes matured, the area of each cell body decreased while the aspect ratio increased. These results are qualitatively in agreement with previously reported experimental studies.

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Adherens junction (AJ), which links actin cytoskeletons in adjacent cells, directly senses and balances intercellular tension that drives dynamical processes such as morphogenesis and wound healing. As a mechano-sensitive molecule at AJ, α-catenin recruits vinculin under intercellular tension resulting in local actin remodeling. However, little is known about mechanical behaviors of α-catenin after vinculin recruitment. In general, adhesive molecules such as a-catenin tend to unfold under low tension. Here, we revealed how a-catenin steadily transmit intercellular tension while keeping the interaction with vinculin, by employing single-molecule interaction measurement using atomic force microscopy (AFM). In our experiments, AFM probe modified with vinculin was contacted to α-catenin-modified substrate resulting in the formation of α-catenin-vinculin complex that which was finally loaded. As a result, we found that α-catenin changes its conformation under intercellular tension in order to conserve the interaction with vinculin. Furthermore, we suggested that an intramolecular interaction in a-catenin influences the unbinding force between a-catenin and vinculin.

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In this study, we have developed a microfluidic device to control chemical stimulation to a cell population at a single cell scale for cell-based assay. The device consists of a cell culture chamber and microfluidic probe (MFP) channels which are possible to control pinpoint chemical stimulation in the microspace. The device has been evaluated by a computer simulation using Finite Element Method (FEM) and a flow control experiment. A control of chemical stimulation between a single cell scale and a cell population scale in the chamber can be possible by regulating flow ratio and channel size of the microfluidic probe. By using the method, we succeeded staining of single cell in a microspace. We conclude that the device can be a powerful tool for biological applications such as the differentiation control of pluripotent stem cells and other cells signaling studies.

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Rabbit patellar tendon-bone complex specimens were subjected to impact tensile load to simulate the sports accident. During the tests, microdamage initiation and accumulation process in tendon was monitored using acoustic emission (AE) technique. In addition, in-situ observation from vertical and horizontal directions using two high-speed cameras was carried out to determine the strain distribution. The stress increased monotonically to the ultimate tensile stress (UTS), which was significantly higher than the static tests. Despite of the extremely short time, a number of AE signals were detected continuously before the UTS. Furthermore, AE signals were emitted in the area where the local strain increased significantly in the strain distribution of the surface. It is then demonstrated that AE technique enables not only the detection of invisible microdamage but the identification of the damage location. It is worth nothing that the amplitudes of detected AE signals were much higher than static tests. Since AE amplitude corresponds to the magnitude of individual microdamage, it is suggested that larger magnitude of individual microdamage is initiated under impact tensile load. Consequently, it is demonstrated that AE technique has a possibility of clarifying the detailed rupture mechanism of tendon or ligament under impact load.

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The tooth axis is an important as a morphological reference axis. However, a general definition of the tooth axis has not been established. The aim of this study was to use cone beam computed tomography (CBCT) to determine three-dimensional tooth axes (PC-A) based on principal component analysis automatically, and to estimate errors in the axes compared with those determined using micro-computed tomography (μCT), the standard of reference. We compared the tooth axis PC-A using three differential modes of CBCT (spatial resolution: D-mode = 0.1 × 0.1 × 1.0 mm^3, I-mode = 0.19 × 0.19 × 1.0 mm^3, A-mode = 0.3125 x 0.3125 x 1.0 mm^3) and uCT (spatial resolution: 0.033 × 0.033 x 0.033 mm^3) imaging of 22 human teeth: three incisors, four canines, seven premolars, and eight molars. The average relative angular errors and distance errors of PC-A between μCT and I-mode of CBCT were 0.51 ± 0.22 deg. and 0.16 ± 0.10 mm, respectively. As experimental results using the 22 teeth, the average relative angular errors between the tooth axes manually specified by three dentists and the PC-A automatically calculated from I-mode of CBCT with the proposed method were 1.97 ± 0.60 deg. for incisors, 1.92 ± 0.96 deg. for canines, 3.05 ± 1.28 deg. for premolars and 3.98 ± 1.43 deg. for molars, respectively.

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Spherical indentation testing is studied to evaluate the muscle stiffness of human shoulder. Here, the Hertzian contact theory is functionally extended to evaluate indentations for the thin tissues on the human body. In the expansions, the technique used for evaluating the thickness of finite specimens is first explained by analyzing the experimental results of indentations. Then, the elasticity of soft materials with finite thickness is theoretically derived by defining an equivalent indentation strain for the analysis of the indentation process. The expansions are examined to evaluate its reliability by applying them to measure the stiffness of some soft materials. Furthermore, this technology is applied to the elasticity investigation of the human body. Especially, the measurement results of elastic characteristics of the body of human body are shown and the availability of developed device is discussed to reveal the deformation mechanics of human body in this report.

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The ossicular chain, which consists of the malleus, the incus and the stapes, plays an important role in auditory mechanics. If the ossicles become fixed somewhere, hearing loss occurs. In order to improve the level of hearing, the fixed part of the ossicles must be replaced. It is important to evaluate the mobility of the stapes in the so-called tympanoplasty surgery, because it affects the prognosis for the improvement of the hearing level. However, a clearly objective measurement of the stapes mobility has up to now not been performed. In a previous study, we suggested a mechanism that allowed to push the ossicles by use of a probe during a surgery. Then we performed the evaluation of the ossicular mobility using a force sensor and an actuator. In this study, we try to put the new mechanism into practice. The probe of the measuring system consists of an ear-pick, a strain gauge fixed to an actuator and a force sensor. We vibrate the ossicles with the ear-pick and measure the reaction force and displacement of the ossicles by the force sensor and the strain gauge. From the relationship between the reaction force and the displacement, we can judge the anchoring of auditory ossicles adherence degree.

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Irreversible electroporation (IRE) is a new method to necrotize cancer cells by applying a short, intensive electric pulses to the targeted tissue. One of the advantages of this method is that the extracellular matrix can be kept intact whereas only the cells are ablated. Prior to the treatment, numerical simulation to predict the affected area by IRE is necessary to improve clinical outcome. Therefore, the aim of this study was to compare the ablation area resulted from 3-D cell culture experiments with the electric field distribution derived from numerical analysis. In the experiments, the ablation area gradually increased depending on the pulse repetition and pulse interval. However, numerical analysis failed to estimate the pulse-dependent increase of the ablation area because the analysis of static electric field couldn't exhibit the dynamic expansion of cell breakdown. This study showed that not only electric field but also dynamic effects of pulse repetition and interval are important to predict ablation area.

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In this study, we target at Pulmonary Hypertension. The good treatment of the timing is essential to the disease that is an intractable disease. Now, the diagnosis method of the Pulmonary Hypertension called the Pulmonary Vascular Resistance (PVR) is used in medical care. However, this diagnosis method is vague. This is caused by the conditions except the blood vessel. The main purpose of this study reported here is to consider pulmonary artery as an elastic duct line and analyze an internal wave motion phenomenon and to propose the new diagnosis method of the Pulmonary Hypertension.

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New growth in the micro-vascular network around cancerous tissue can be typically observed, i.e. angiogenesis, which should give rise to the proliferation and metastatic spreading of cancer cells. Therefore, an in vivo diagnosis of blood velocity is quite necessary to diagnose cancerous tissue. In this paper, we propose OCDV (Optical Coherence Doppler Velocigraphy), which is a method of tomographic micro-visualizing fluid velocity based on a high frequency modulated low coherence interferometer. The rapid scanning optical delay line was implemented as a reference arm so as to visualize video-rate tomography of velocity field. This system applied experimentally to a simplified simulation of an arteriole, consisting of a rectangular microchannel which is buried to a depth of approximately 300μm with resin and pumped intralipid solution (2%). Consequently, this could offer tomographic velocity in micro circulation, as in vivo tomographic diagnosing tool of blood flow velocity profiles in tissue.

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Electronic devices such as LSI, introduced to medical devices, have been being improved in terms of high efficiency and integration of micro and power semiconductor elements. The quantity and density of generated exothermic Joule heat have been increasing, so that this could lead to serious problems, i.e. microscopic thermal fracture. Therefore, it is quite necessary to carry out the optimum thermal management and design just in micro scale. In this study, non-destructively and tomographically micro-visualization of temperature is proposed, namely Optical Coherence Thermography (OCTH). This system is constructed under tomographic detection technique of thermal deformation from Tomographic OCT images, i.e. Optical Coherence Straingraphy (OCSA), as well as the inverse analysis based on FEM. In order to validate OCTH, the numerical experiment was carried out using simulated OCT images based on FEM thermal stress analysis of semiconductor. As a result of accuracy verification, it is concluded that OCTH can visualize temperature tomography at the micrometer scale with suppressed 8% error. The proposed OCTH is considered to have high potential in thermal design of MEMS.

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Bone tissue is composed of bone matrix. Bone matrix is mainly composed of apatite and type I collagen. Apatite is inorganic matrix. Type I collagen is organic matrix. Therefore, microscopic molecular structure and crystal structure are related to macroscopic bone stress. Structural information of organic and inorganic state are useful to estimate bone stress. Raman spectroscopy is non-invasive structural analysis method based on molecule inherence Raman scattered light generated by irradiating the laser with a single wavelength to the material. In previous study, the relationship between Raman shift and mechanical stress was investigated. Raman spectrum was obtained from single measurement point. However, the change of Raman shift related to stress is varied at different measurement point. In this study, to improve the repeatability of mechanical analysis by using Raman spectroscopy, we propose the statistical method by Raman imaging system. Raman spectroscopies for bovine cortical bone specimens were carried out under tensile load. Three types of specimens were prepared for circumferential irradiation under axial tensile loading, radial irradiation under axial tensile loading and radial irradiation under circumferential tensile loading. Measurement area was 60 × 60 μm, scanning interval was 1.5 μm and measurement points was 41 × 41 points. Changes of Raman shift of specific 7 peaks derived from apatite or type I collagen under stress were analyzed. Changes of Raman shift with applied tensile stress at bone circumferential direction were lager than changes of Raman shift applied tensile stress at bone axial. The difference between measurements of radial section and circumferential were mostly little.

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Bone is often regarded as a composite material consisting of mineral particles and organic matrix (mostly Type I collagen) on a microscopic scale. The mechanical properties of bone tissues at a macroscopic scale depend on the structural organization and properties of constituents in the microscopic scale. However, both mechanical behaviors of mineral and collagen phases are not clear yet. In this study, both microscopic strain of collagen and mineral phases in cortical bone by using small and wide angle X-ray diffraction, respectively. The collagen matrix strain allowed tensile deformation as compared with mineral phase. This study could suggest that macroscopic mechanical properties of bone tissue depend on the degree of deformation of mineral and collagen matrix.

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Vertebral fracture of osteoporosis patients often lead to vertebral progressive collapse that results in a variety of comorbidities. Prediction of progressive collapse is so difficult that cancellous bone had characteristic stress-strain curves after yield stress. The purpose of this study was to reveal relationships between decreases in mechanical properties and structural indices of the cancellous bone as a model of progressive collapse with the cyclic compression test. A total of 15 cubic cancellous bone specimens were obtained from three regions of a 2-year-old bovine femur (n = 2): femoral head, neck, and proximal metaphysis. Structural indices of each specimen were determined using micro-computed tomography. Finally, deference of bone volume fraction (D BV/TV) between pre- and post- experiment was calculated with μCT. The specimens were then subjected to 5 cycles of uniaxial compressive loading from 0.3 mm displacement to unloading to 0.2 mm for five successive cycles. The decrease ratio of elastic modulus from baseline to fifth cycle was also correlated with BV/TV (r = 0.80, p < 0.01) and SMI (r = - 0.78, p < 0.01). The decrease ratio of yield stress from baseline to fifth cycle was strongly correlated with bone volume fraction (BV/TV, r = 0.96, p < 0.01) and structural model index (SMI, r = - 0.81, p < 0.01). D BV/TV were correlated with partial BVATV (P BV/TV) in under 35% and over 50% of P BV/TV groups (p < 0.01). Structural deterioration of cancellous bone is associated with the bone strength in progressive vertebral collapse.

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Microdamage of healthy bovine cortical bone specimen and decalcified bone specimen during static compression tests was monitored by acoustic emission (AE) technique. Microdamage accumulation was successively monitored by AE technique. In static compression tests of healthy bone specimen, cracks were propagated due to microdamage accumulation, and cumulative AE events increased before final fracture. In static compression tests of decalcified bone specimen, macrocrack was observed with increasing in cumulative AE energy and cumulative AE events and decreasing in stress before fracture. Maximum stress and Young's modulus between healthy bone specimen and decalcified bone specimen had a significant difference. Those between specimen A (decalcified only specimen inside) and specimen B (decalcified specimen inside and outside) had no significant difference. Microdamage accumulation process of healthy bone specimen and decalcified bone specimen before leading to final fracture was shown by AE technique.

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In total hip arthroplasty, the use of metal-on-metal bearings (MOM) had been increasing with expansion of demand for higher physical activities in young patients before clinical studies reported that metal ion release caused by wear leads to metal allergy and pseudotumour. Using ELID grinding system we have developed low friction and wear MOM to reduce these adverse reactions. The ELID system produces thick oxide layer on bearing surface that can inhibit metal ion release. The lubrication performance on friction and wear depends on geometric design and surface feature. Therefore, this study demonstrated the optimal clearance of the newly developed MOM for reducing metal ion release. We evaluated the influence of diametrical clearance on friction using a hip friction simulator. The nine φ36 mm femoral heads and 9 liners were prepared with 13 nm in roughness (Ra), and 2 μm in sphericity and were divided into three bearing groups based on the diametrical clearance (C_d = 20, 50, 70 μm). The frictional moment generated in each bearing under walking was measured and the frictional coefficient was calculated. The frictional coefficient decreased with reducing in the clearance but, maximum value was observed in C_d = 20 μm. In the clearance group of 20 μm, we expected the hydrodynamic lubrication because the Λ value defined as the ratio between lubricant thickness and average roughness is almost 3.0. Too small clearance induced the severe contact. Thus, our results suggest that the optimal clearance of new MOM is 50 μm to enhance lubrication performance.

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Motion capture systems estimate underlying bone movements by tracking trajectories of skin-mounted markers. However, the reliability of the kinematics parameters derived from the skin markers has often questioned due to skin movement artefact. The objective of this study was to evaluate skin movement artefact associated with dorsiflexion and plantar flexion of the foot using 3D bone models and bi-plane radiography. Four healthy subjects participated in this study. The subject underwent CT scan to reconstruct 3D tibial, the first metatarsal bone, and the fifth metatarsal bone models. Sixteen polymeric markers with radio-opaque beads in its center were attached to the shank and foot. To quantify the skin marker movement with respect to the tibia, the first metatarsal bone, and fifth metatarsal bone, bi- plane radiographic images were collected during neutral, plantar flexion, and dorsiflexion of the foot. The positions of the tibia, the first metatarsal bone, and the fifth metatarsal bone were recovered by a 2D to 3D image registration method. Then the positions of the markers were determined with respect to the relevant coordinate system embedded in the 3D bone models. The mean values ± SD of the translations in the corresponding markers with plantar flexion were 3.1 ± 1.8 mm for the tibia, 8.2 ± 4.2 mm for the first metatarsal bone, and 14.0 ± 6.3 mm for the fifth metatarsal bone. With dorsiflexion, the translations were 6.0 ± 3.1 mm for the tibia, 18.1 ±6.4 mm for the first metatarsal bone, and 36.0 ±12.8 mm for the fifth metatarsal bone.

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Patients of knee arthropathy such as knee osteoarthritis have been increasing due to increasing population of elderly people. Such arthropathy is caused by initial wear of a knee cartilage followed by deformation of lower limb skeleton causing inflammation in a knee joint. A pain occurring from the inflammation makes patients have difficulty walking in daily lives and increases the likelihood of having lifestyle related diseases such as osteoporosis. Among conservative treatments, knee braces are used by the patients in an orthotic treatment. In the research, knee braces with linkage mechanisms developed to reduce the pain in knee joint felt by the patients were used. Specifically, the knee braces lighten the force by distributing weight of the upper body to their bars and reducing the force acting on the surface of the knee joint. In the experiments, three kinds of knee braces for a left foot each containing different lengths of 4 bar linkage in the medial side were used. The experiment was done by first attaching strain gauges to the bars of the braces to measure the strains on the bars. The subject next wore the braces in order to measure the strains that occur while sitting (flexing knee) and standing (extending knee). Finally, compression forces on the bars were calculated from the strains measured in order to evaluate the percentage of body weight distributed from the joint to the bars.

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In the forearm, there are 19 muscles controlling finger motions. To measure the muscle activity in the forearm is essential to evaluate paralyzed muscles. In previous study, EMG-CT method was proposed to measure the muscle activity pattern in the forearm noninvasively. The aim of the current study was to investigate the muscle activity in the forearm during various finger loadings under the pronation, neutral, and supination positions of the forearm by using EMG-CT. Three healthy young males participated in the experiments. As a result, muscle activity pattern was different with the forearm positions. Activated area was rotated corresponding to the changes of muscle arrangements with the forearm positions and agreed with anatomical knowledge. Furthermore, the total muscle activity in the whole cross-section increased with the applied load in each loading condition. The study showed that the muscle activity pattern was observed corresponding to the muscle arrangement in the pronation, neutral, and supination positions by using EMG-CT.

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Nihon University and Nippon Medical School Chiba Hokuso Hospital has researched traffic accidents by using some injury evaluation index. The purpose of this study is to compare the injury evaluation index, which is verify the four evaluation index of MAIS (Maximum Abbreviated Injury Scale), ISS(Injury Severity Score), the number of treatment days of Japanese police definition and the treating physicians assessment. And this physicians assessment has constructed by treated at ICU, Presence or absence of Emergency operation, transcatheter arterial embolization (TAE) and blood transfusion. In the results, the subjective assessment by the treating physician is the ratio to evaluate the serious injury is the third highest at 35%. And the definition of Japanese police is highest at 62%.

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Thoracoabdominal injury by a crowd of people is serious problem for crowd accident. To reduce the number of victims, it is important to make the criteria of thoracoabdominal injury clear. Therefore, the purpose of this research is to develop animal experiment model for breakthrough the criteria of thoracoabdominal injury. This paper studies on the experiment in which the compression load is set once and twice heavier than the weight of experimental subject. As a result, with increase in compression load, it was found that tidal volume reduced and respiratory rate increased.

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Quantitative data of spine alignment is required during positioning of human body model, analysis of spine-related injury mechanism and ergonomic study of vehicle seat. Although spine alignment varies depending on individuals and body postures, only few studies regarding the variation of spine alignment can be found. In this study, by fitting Bezier curve on the lateral X-ray images of spine in standing and sitting posture, variations in spine alignments were quantified. Furthermore, relationships between the spine alignment and body pressure during sitting or EMG of abdominal muscle were also clarified. As a result, large variation in spine alignment could be found in cervical and lumbar spine. Cervical spine showed an increased tendency of S-shaped curvature during sitting posture compared to standing posture. Lumbar spine indicated a strong trend of lordotic and kyphotic curvature during standing and sitting posture respectively. Moreover, the maximum value of normalized iEMG in sitting posture was found to be higher than in standing posture. Comparisons of normalized maximum body surface pressure and contact area between two typical cervical and lumbar spine curvatures showed that the differences were not significant.

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In this research was constructed head FE model for performing impact analysis for the purpose of elucidating the mechanism of head injuries in the elderly. Elderly brain tissue atrophy has progressing compared to the young people, and the intracranial cavity is enlarging. Therefore, the head impact resistance of elderly are to be lowered. We build the model based on head CT image data of the young people. Elderly model was reproduced atrophy of volume reduction rate 6.87%, by deforming the image processing intracranial tissue on the CT image of young people.

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Whiplash injury with neck pain is the most frequent injury due to low-speed rear-end impacts in Japan, but the injury mechanism is still unknown. Some researchers proposed their hypotheses for the injury mechanisms from their studies based on Post Mortem Human Subject (PMHS) tests, volunteer tests, and computer simulations using human body finite element (FE) models. Although the human body FE models are useful to evaluate the hypotheses, the active muscles should be modeled and integrated with a human body FE model to investigate the injury mechanism in real-world accidents. In this study, we developed a human body FE model with active muscles and a muscle controller for posture maintenance. The model was used under a rear impact condition with 8 km/h, and reproduced the same head-neck responses as the volunteer test data. The human body FE model with the muscle controller have the potential to investigate damages due to elongations of neck muscles during low-speed rear-end impacts.

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Liposomes are expected as a drug carrier ideal for drug delivery systems. Release have been proposed in liposomes many studies to control drug. One method is to apply a physical stimulation such as an ultrasonic field, magnetic field, temperature, light and so on. In this paper, to investigate whether there is any effect on the release of the liposome by ultrasonic and heating.

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Micro slurry-jet erosion has been proposed as a precision machining technique for the bearing surfaces of artificial joints in order to reduce the total amount of polyethylene wear and to enlarge the size of the wear debris. The micro slurry-jet erosion method is a wet blasting technique which uses alumina particles as an abrasive medium along with compressed air and water to create an ideal surface. From pin-on-disc wear tests with multidirectional sliding motions, the textured surface on a Co-Cr-Mo alloy could change the total amount of wear of polyethylene.

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This paper presents evaluation of proinflammatory cytokine production amount released by human monocyte-derived macrophages (HMDM) in order to elucidate the effect of wear particles produced by artificial joint on in-vivo immune-function. Polymethylmethacrylate (PMMA) particles were used instead of wear particles for evaluation of effects of particle size on biological responses. The cytotoxicity evaluation test was carried out for evaluating the viability of HMDM which ingested PMMA particles by lactate dehydrogenase activity assay. Also, proinflammatory cytokines production ability of PMMA particles ingested HMDM was evaluated by enzyme-linked immunosorbent assay. As a results, viability of HMDM was approximately 90% or more in the case of PMMA particle size of 0.8, 5.6, 9.6 μm, and was approximately 75% or less in the case of PMMA particle size of 0.16 μm. This result indicates that the HMDM viability was not dependent on the size and the amount of PMMA particles in the case of particle size of 0.8 μm or more. On the other hand, the proinflammatory cytokine production activity of HMDM was dependent on the size of PMMA particles, and 0.8 μm PMMA particle strongly induced the proinflammatory cytokine production.

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