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In recent years, there has been growing demand for flat electrical machines in order to minimize system size while also maintaining high efficiency. In general, axial flux machines (AFMs) are more suitable for flat form than radial flux machines (RFMs). AFMs usually employ a soft magnetic composite (SMC) for the stator core, and their efficiency can be improved by employing an SMC that has low iron loss. However, this reduces the average torque because there is generally a tradeoff relationship between iron loss and magnetic permeability in SMCs. This article, therefore, proposes an AFM with a coreless rotor structure in which the torque performance is not easily affected by the permeability of the SMC. This article aims to reveal the ideal SMC characteristics for high efficiency in AFMs. First, many virtual SMC materials with different iron loss and permeability are used for simulations of AFMs in order to investigate sensitivity to material properties. The simulations by virtual SMCs take into account the experimental increase in the iron loss. As a result, guidelines for developing SMCs are constructed based on the experimental results. Finally, prototype AFMs employing new SMCs developed by following the guidelines are shown, and it is found that they offer higher efficiency in all operating area than conventional AFMs. In particular, one prototype achieves an extremely high efficiency of over 96% at 6000 r/min, 0.8 Nm in experiments.

Fibrosis is a condition characterized by the overproduction of extracellular matrix (ECM) components (e.g., collagen) in the myofibroblasts, causing tissue hardening and eventual organ dysfunction. Currently, the molecular mechanisms that regulate ECM production in the myofibroblasts are still obscure. In this study, we investigated the function of GPRC5B in the cardiac and lung myofibroblasts using real-time RT-PCR and siRNA-mediated knockdown. We discovered a significantly high expression of Gprc5b in the tissues of the fibrosis mice models and confirmed that Gprc5b was consistently expressed in the myofibroblasts of fibrotic hearts and lungs. We also found that Gprc5b expression was associated and may be dependent on the actin-MRTF-SRF signaling pathway. Notably, we observed that Gprc5b knockdown reduced the expression of collagen genes in the cardiac and lung myofibroblasts. Therefore, our findings reveal that GPRC5B enhances collagen production in the myofibroblasts, which directly promotes fibrosis in the tissues.

Sintered materials are superior in productivity because of their simple process, but they are not applied to high-load gears because of their insufficient strength. To improve the fatigue strength of sintered materials, the authors have developed liquid-phase sintering which can achieve high-density without using secondary processing. In this study, the effect of boron addition (0-0.4 mass%) on the rolling contact fatigue strength of Fe-Ni-Mo-B-C sintered and carburized material was evaluated. In addition, in order to evaluate only the boron addition effect excluding the influence of density, the sintered density of each specimen was controlled to be the same. In the test range of this study, the rolling contact fatigue limit (pmax)lim of material with an additional quantity of boron of 0.1 mass% showed the highest value exceeding 1700 MPa. This value was not only significantly higher than the (pmax)lim of the boron-free material (1100 MPa), but also an extremely high value comparable to the (pmax)lim of wrought steel (1900 MPa). The reason why the (pmax)lim of a 0.1B roller was remarkably high was investigated from the viewpoints of both pore structure and material structure. As for the pore structure, the pore shape of the boron-free roller was irregular, whereas the pore shape of the 0.1B roller was spherical. As a result of CAE analysis of the orthogonal shear stress inside the roller during the rolling contact fatigue test, it was found that the maximum value of orthogonal shear stress around the pores of the 0.1B roller was about 35 % lower than that of the boron-free roller. This result suggests that cracks are less likely to occur in the 0.1B roller than in the boron-free roller. In other words, it is thought that the pore shape of 0.1B material affects the improvement of rolling contact fatigue strength.

Sintered materials are superior in productivity because of their simple process, but their mechanical properties are low. To improve the mechanical properties of sintered materials, we focus on liquid-phase sintering. In this study, we selected boron as sintering aids and evaluated on the effect of the addition quantity of boron (0-0.6 mass%) to the mechanical properties of liquid-phase sintered and heat-treated materials. In the test range of this study, the tensile strength of material with an additional quantity of boron of 0.1 mass% showed the highest value, 1386 MPa, which is about 35% higher compared to the tensile strength of material without adding boron. On the other hand, materials with an additional quantity of boron of 0.2 mass% or higher showed higher-density than material with an additional quantity of boron of 0.1 mass%, but both their elongation and tensile strength were significantly decreased. The precipitates changed between the boundary of the quantity of boron added of 0.1 and that of 0.2 mass%. Only Fe23B6 was formed in the material with the boron addition amount of 0.1 mass% or less, and Fe23B6 and Fe2B were formed in the material with the boron addition amount of 0.2 mass% or more. By cross-sectional observation of the test specimen after the tensile test, it was confirmed that in the material with the boron addition amount of 0.2 mass% or more cracks occurred and propagated at the Fe23B6/Fe2B interface and finally resulted in fracture. In the material with the boron addition amount of 0.1 mass%, however, such a fracture was not confirmed. The phenomena could be explained the fact that the mechanical properties were sharply changed between the quantity of boron added of 0.1 mass% and 0.2 mass%. The existence of Fe23B6/Fe2B interface would significantly affect the strength of the liquid-phase sintered materials.

International audience; Accentuated by the ongoing coronavirus disease (COVID-19) pandemic, the change in Japan to community-based health and care services for older adults indicates an urgent need to enhance and spread citizens’ understanding of care. This is a broader notion of care that incorporates conditions within the community to support the inclusion of older adults, involving not only those older adults receiving care and their direct providers of care, but also others in the community who are involved in the daily lives of these older adults. To underpin such a broader notion of care across citizens, this paper proposes ‘care literacy’ as a novel analytical concept, defined as the knowledge and capabilities that enable people in need of care to live their daily lives in the community and facilitate potential health and care solutions. Reflecting the interconnection of health and care and rooted in the local context, care literacy underpins aging by enabling this involvement of the broader community, and is disseminated through media and grassroot activities.

In recent years, electric motors having flat shape are desired in order to minimize system size as well as enhancing the efficiency. Therefore, axial gap motors (AGMs) have attracted significant attention because they can achieve higher torque density in flat shape than that of conventional radial gap motors (RGMs). In general, AGMs employ the soft magnetic composite (SMC) for the stator core since they have three dimensional magnetic paths unlike RGMs. If AGMs employ the SMC which has low iron loss characteristic, the efficiency can be improved. On the other hand, the average torque is decreased because the SMC basically has tradeoff-relationship between the iron loss characteristic and the permeability. Hence, in this research, an AGM having coreless rotor structure that torque performance is not easily affected by the permeability of the SMC is proposed. In this paper, many virtual SMC materials which have different iron loss and permeability are considered for the proposed AGM employing the coreless rotor structure. Finally, suitable SMC characteristic to enhance the efficiency over a wide operating range is revealed by three-dimensional finite element analysis (3D-FEA).

Fibrosis is attributed to excess deposition of extracellular matrix (ECM) proteins including collagen and is associated with various organ dysfunction. This excessive ECM is produced by myofibroblasts, which are differentiated from various cells by a variety of stimuli, represented by TGF-β. However, molecular mechanisms for the regulation of ECM production in myofibroblasts remain obscure. In this study, we demonstrate that the expression of drebrin, which binds to and increases the stability of actin filament in neurons, is increased in mouse hearts and lungs upon fibrosis. Drebrin is mainly expressed in myofibroblasts in the fibrotic hearts and lungs and promotes the expression of fibrosis-related genes, such as Acta2 and Col1a1. Taken together, our study identifies drebrin as a molecule that promotes the production of fibrosis-related genes in myofibroblasts.

Here, we present a study on exoskeleton robot control based on inter-limb locomotor synergies using a robot control method developed to target hemiparesis. The robot control is based on inter-limb locomotor synergies and kinesiological information from the non-paretic leg and a walking aid cane to generate motion patterns for the assisted leg. The developed synergy-based system was tested against an autonomous robot control system in five patients with hemiparesis and varying locomotor abilities. Three of the participants were able to walk using the robot. Results from these participants showed an improved spatial symmetry ratio and more consistent step length with the synergy-based method compared with that for the autonomous method, while the increase in the range of motion for the assisted joints was larger with the autonomous system. The kinematic synergy distribution of the participants walking without the robot suggests a relationship between each participant's synergy distribution and his/her ability to control the robot: participants with two independent synergies accounting for approximately 80% of the data variability were able to walk with the robot. This observation was not consistently apparent with conventional clinical measures such as the Brunnstrom stages. This paper contributes to the field of robot-assisted locomotion therapy by introducing the concept of inter-limb synergies, demonstrating performance differences between synergy-based and autonomous robot control, and investigating the range of disability in which the system is usable.

In general, radial gap motors employing neodymium sintered permanent magnet (Nd sintered PM) are used to achieve high torque density in many applications. However, the motors are not suited to a flat, disk-like shape because the dead space, such as the coil ends, occupies most of the motor volume. Therefore, axial gap motors are frequently used for flat shape instead of radial gap motors. Nd sintered PM is a well-known high-performance magnet that has high residual magnetic flux density, but eddy current loss easily occurs in the magnet because of its high conductivity. In axial gap motors for industrial applications, it is difficult to take measures against eddy current loss of Nd sintered PM in terms of cost. Therefore, general axial gap motors employing Nd sintered PM often have unsatisfactory characteristics, such as low efficiency, even though the motor produces high torque. On the other hand, radial gap motors can take measures to suppress eddy current in PMs easily if radial gap motors employ interior permanent magnet structure. Accordingly, this paper discusses an axial gap motor employing neodymium bonded permanent magnet (Nd bonded PM) for flat shape. Compared with Nd sintered PM, Nd bonded PM has lower residual magnetic flux density, but also lower cost. In addition, Nd bonded PM has extremely low eddy current loss due to its low conductivity. It is found from three-dimensional finite element analysis and experimental results that the axial gap motor employing Nd bonded PM can achieve higher torque and higher efficiency compared with the radial gap motor employing Nd sintered PM with the same PM weight and a flat shape.

Context: The hybrid assistive limb (HAL) (the wearable robot) can assist kinesis during voluntary control of hip and knee joint motion by detecting the wearer's bioelectric signals on the surface of their skin. The purpose of this study was to report on walking ability following the wearable robot treatment in a patient with chronic myelopathy after surgery for cervical ossification of the posterior longitudinal ligament (OPLL). Findings: The patient was a 66-year-old woman with cervical OPLL who was able to ambulate independently with the aid of bilateral crutches. The wearable robot treatment was received once every 2 weeks for ten sessions beginning approximately 14 years after surgery. Improvements were observed in gait speed (BL 22.5; post 46.7 m/min), step length (BL 0.36; post 0.57 m), and cadence (BL 61.9; post 81.6 m/min) based on a 10-m walk test and a 2-minute walk test (BL 63.4; post 103.7 m) assessing total walking distance. The improvements in walking ability were maintained after the wearable robot treatment for 6 months. Conclusion: We report the functional recovery in the walking ability of a patient with chronic cervical myelopathy following the wearable robot treatment, suggesting that as a rehabilitation tool, the wearable robot has the potential to effectively improve functional ambulation in chronic cervical myelopathy patients whose walking ability has plateaued, even many years after surgery.

Patients with complete quadriplegia after high cervical spinal cord injury are fully dependent with activities of daily living. Assistive technology can improve their quality of life. We examined the use of a hybrid assistive limb for single joints (HAL-SJ) in a 19-year-old man with complete C4 quadriplegia due to chronic spinal cord injury to restore function of active elbow flexion. This is the first report on the use of the HAL-SJ in a patient with spinal cord injury.The HAL-SJ intervention for each elbow was administered in 10 sessions. Clinical assessment using surface EMG was conducted to evaluate muscle activity of the trapezius, biceps brachii, infraspinatus, and triceps brachii muscle before, and during the 2nd, 3rd, 6th, and 9th interventions. Surface electromyography (EMG) before intervention showed no contraction in the upper arms, but in the bilateral trapezius. The HAL-SJ used motion intention from the right trapezius for activation. After the 6th and 7th session, respectively, biceps EMG showed that voluntary contraction and right elbow flexion could be performed by motion intention from the right biceps. After the 10th session, voluntary bicep contraction was possible. HAL-SJ treatment on the left elbow was performed using the same protocol with a similar outcome. After completing treatment on both upper extremities, both biceps contracted voluntarily, and he could operate a standard wheelchair for a short distance independently.HAL-SJ intervention is feasible and effective in restoring elbow flexor function in a patient with C4 chronic spinal cord injury and complete quadriplegia.

Herein we present the development of a novel Ankle Foot Orthosis for gait support of people with foot-drop symptoms. The developed AFO uses an elastic link mechanism to brake the ankle joint during initial contact, thus mitigating foot-slap, and an integrated energy store-and-release mechanism to support toe lift in the swing phase, thus mitigating toe-drag. This paper presents improvements in the braking-holding power of the elastic link mechanism over its previous version, the torque-angle characteristics of the developed AFO with the renewed elastic link, and a pilot test with one person with foot-drop symptoms to verify the proposed functions of the developed AFO.

In recent years, permanent magnet synchronous motors (PMSMs) are used for many applications because of their high output density and high efficiency. On the other hand, PMSMs having low aspect ratio like flat disk are desired depending on applications. In general, PMSMs employ radial gap structure which has the air gap in radial direction. However, in flat shape, radial gap motors have relatively low torque because their effective surface area of permanent magnet (PM) is small and their coil ends occupy most of the motor volume. Therefore, in flat shape, axial gap structure which has the air gap in axial direction is frequently employed instead of radial gap motors. Since axial gap motors don't have the coil ends in axial direction, they can reduce axial length. Meanwhile, conventional axial gap motors frequently employ double stator structure. Hence, in flatter shape like ‘ultra-flat shape’, conventional axial gap motors are not suitable because stator back yoke and PM become extremely thin. Instead of those, an axial gap motor employing C-type SMC core is proposed in this paper. Advantages of the proposed axial gap motor using C-type core in ultra-flat shape is illustrated, and then, the proposed motor is analyzed by three-dimensional finite element analysis (3D-FEA).

We hypothesized that a single-leg version of the Hybrid Assistive Limb (HAL) system could improve the gait and physical function of patients with hemiparesis following a stroke. In this pilot study, we therefore compared the efficacy of HAL-based gait training with that of conventional gait training (CGT) in patients with acute stroke. Patients admitted to the participating university hospital were assigned to the HAL group, whereas those admitted to outside teaching hospitals under the same rehabilitation program who did not use the HAL were assigned to the control group. Over 3 weeks, all participants completed nine 20 min sessions of gait training, using either HAL (i.e., the single-leg version of HAL on the paretic side) or conventional methods (i.e., walking aids and gait orthoses). Outcome measures were evaluated before and after the nine training sessions. The Functional Ambulation Category (FAC) was the primary outcome measure, but the following secondary outcome measures were also assessed: National Institutes of Health Stroke Scale, Fugl–Meyer Assessment (Lower Extremity), comfortable walking speed, step length, cadence, 6-min walk distance, Barthel Index, and Functional Independence Measure. In total, 22 post-stroke participants completed the clinical trial: 12 in the HAL group and 10 in the CGT group. No serious adverse events occurred in either group. The HAL group showed significant improvement in FAC after nine sessions when compared with the CGT group (P = 0.014). However, secondary outcomes did not differ significantly between the groups. Our results demonstrate that HAL-based gait therapy may improve independent walking in patients with acute stroke hemiplegia who are dependent on ambulatory assistance. A larger-scale randomized controlled trial is needed to clarify the effectiveness of single-leg HAL therapy. Clinical Trial Registration: UMIN Clinical Trials Registry, identifier UMIN000022410.

To investigate whether Robot Suit HAL treatment (HAL-T) is safe and feasible for gait disorders in adolescents and adults with cerebral palsy (CP). We tested HAL-T in adolescents and adults with bilateral spastic CP (four men, four women; mean age: 18.2 years). Three participants were classified as level III under the Gross Motor Function Classification System (GMFCS), and five were classified as level IV. The participants underwent HAL-T twice per week for 4 weeks. The outcome measures, which were assessed before and after HAL-T, included comfortable gait speed (CGS), step length (SL), cadence, and GMFCS level. Adverse events were noted. All participants completed the HAL-T sessions despite some mild adverse events occurring. The mean increases in CGS, SL, and cadence were 0.19 ± 0.14 m/s (p = 0.006), 0.09 ± 0.08 m (p = 0.020), and 18.0 ± 15.9 steps/min (p = 0.015), respectively. HAL-T is safe and feasible for gait disorders in patients with CP. HAL-T can significantly improve CGS, SL, and cadence and may be effective for improving walking ability in adolescents and adults with CP.

Iron-based sintered materials are fabricated via the process of compacting iron powder by using die, sintering in 1100 to 1300°C, and quenching or sizing. These materials are used as variable valve system and oil pump system in automobiles. Recently, the severe requirement for complication and high precision shape of them has increased the products machined by turning and drilling. In general, it is more difficult to machine the sintered materials than the steel. However, the quantitative evaluations and the mechanisms of those are ambiguous, then there is a few suggestion for improvement of the machining. In this study, we will report the machinability of sintered materials by compare with that of steel materials, and the improvement of machinability of sintered materials.

An axial gap motor using neodymium bonded magnet, which our research group has proposed, achieved high torque density and high efficiency at high torque region in the previous paper. However, further improvement in efficiency is required in a wide operation range including not only high torque region but also low torque region. Hence, this paper discusses soft magnetic composite (SMC) suitable for high efficiency of the proposed axial gap motor. In the SMC, there is a trade-off relationship between low iron loss characteristic and high magnetic permeability. Therefore, at low torque region, the efficiency of the axial gap motor using the SMC was lower than that of the radial gap motor using the electromagnetic steel sheet. The proposed axial gap motor adopts a coreless rotor structure. Thus, it is possible to suppress the torque reduction, because the magnetic circuit of the proposed axial gap motor is hardly affected by the magnetic permeability of the stator core due to the large magnetic reluctance of the coreless rotor. For the proposed axial gap motor, HX3 of the newly material having lower iron loss characteristic than the electromagnetic steel sheet is developed, even though the magnetic permeability decreases. Consequently, improvement of efficiency and high torque are compatible by HX3. In this paper, we show the material properties of HX3 and the experimental results of a prototype machine of the proposed motor using HX3 of the newly material. From the experimental results, we report that the proposed motor can achieve improvement of efficiency around low torque region.

Most pediatric cancer patients decline physical performance therapy, resulting in limitations in the activities of daily living. The objective of this study was to investigate the effects of rehabilitation in pediatric patients with cancer using the functional independence measure (FIM) score. This retrospective study included 25 inpatient children diagnosed with cancer at a single university hospital from January 2016 to December 2016. All patients underwent rehabilitative intervention during their hospital stay. We investigated the contents of the rehabilitation program and the FIM scores before and after the rehabilitative intervention. The average FIM scores improved in all patients; however, only the total-FIM scores (+4.96 points, P=0.009) and motor-FIM scores (+4.04 points, P=0.005) improved significantly. Conversely, cognitive-FIM score did not significantly improve (+0.92 points, P=0.159). In addition, motor-FIM subgroup scores for locomotion (walk/wheelchair and stairs) were significantly higher (+0.36 points, P=0.039 and +0.64 points, P=0.046, respectively) after rehabilitative intervention, regardless of the length of hospital stay. This study showed that FIM score, particularly motor-FIM score and locomotion subgroup scores, significantly improved owing to participation in inpatient rehabilitation. In conclusion, we found that rehabilitative intervention improved physical activity, especially locomotion.

The hybrid assistive limb (HAL) is a wearable robot suit that assists in voluntary control of knee and hip joint motion by detecting bioelectric signals on the surface of the skin with high sensitivity. HAL has been reported to be effective for functional recovery in motor impairments. However, few reports have revealed the utility of HAL for patients who have undergone surgery for thoracic ossification of the posterior longitudinal ligament (thoracic OPLL). Herein, we present a postoperative thoracic OPLL patient who showed remarkable functional recovery after training with HAL.A 63-year-old woman, who could not walk due to muscle weakness before surgery, underwent posterior decompression and fusion. Paralysis was re-aggravated after the initial postoperative rising. We diagnosed that paralysis was due to residual compression from the anterior lesion and microinstability after posterior fixation, and prescribed bed rest for a further 3 weeks. The incomplete paralysis gradually recovered, and walking training with HAL was started on postoperative day 44 in addition to standard physical therapy. The patient underwent 10 sessions of HAL training until discharge on postoperative day 73. Results of a 10-m walk test were assessed after every session, and the patient's speed and cadence markedly improved. At discharge, the patient could walk with 2 crutches and no assistance. Furthermore, no adverse events associated with HAL training occurred.HAL training for postoperative thoracic OPLL patients may enhance improvement in walking ability, even if severe impairment of ambulation and muscle weakness exist preoperatively.