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With the aging of the population and the consequent severe shortage of caregivers, the demand for care robots to assist the elderly is increasing. However, care robots have yet to be widely adopted owing to cost constraints and anxiety issues due to several factors. For instance, care robots are required to have higher functionality than general care devices. It is important to provide both massive power and the appropriate support for the user’s state. However, this requires more sensors to obtain detailed information for user-state estimation and more actuators for physical support, increasing the cost and risk of failure. In a system that has many sensors and operates based on detailed data, the problem of user privacy also emerges. The risk of personal information leakage and the feeling of being monitored increase user discomfort. To support standing up and prevent falling during walking, care robots are required to apply power to the user according to the user state. The position of the center of gravity (CoG) has been used for such state estimation; however, many sensors are required to determine the accurate CoG position. To reduce the number of sensors required for user state estimation, we proposed a method for calculating CoG candidates, and validated the proposed method via experiments. Previous studies have focused solely on normal standing-up motion. However, in daily activities, standing up, walking, and sitting down are a set of motions. In addition, it is not always true that the care robot user can move normally; hence, anomaly detection is beneficial in care robots. Therefore, it is important to estimate the user state considering not only standing-up motion, but also walking and sitting down, as well as any anomaly that may occur during these motions. In this study, we develop an elderly support system that can assist in standing, walking, and sitting based on user state estimation. The CoG candidate calculation method is improved for walking and stand-to-sit movements, and an anomaly detection method using CoG candidates is also proposed. The care robot is designed to be user-driven and provide support for persons with insufficient strength based on state estimation. The experiments verify that the developed system can constantly monitor the user’s state and support a series of movements, such as standing up, walking, and sitting down, with a single robot.

Although the development of robot-based support systems for elderly people has become more popular, it is difficult for humans to understand the actions, plans, and behavior of autonomous robots an...

Due to the global climate change and the substantial increase in impervious area, ‘never flooding’ becomes an unrealistic goal. From the perspective of integrated flood management, the government and public need to reach a consensus on disasters and disaster response, and set a reasonable regional protection standard for the city to jointly respond to disasters. This study establishes an operable framework for setting protection standard. The framework uses cost-benefit analysis and data envelopment analysis to maximize the efficiency of water management, so as to compare the differences between different administrative districts under the same return period and between different return period under the same administrative districts, and then determines the best protection standard. The results find that adopting a unified protection standard will not maximize the benefits of resources, but it can be used as a basis for setting flood control standards for different public facilities and building types.

This paper proposes a novel standing assistance robot, which considers the posture tolerance of its user. In previous studies, conventional assistive robots did not require patients to use their own physical strength to stand, which leads to decreased strength in the elderly. Therefore, an assistive robot that allows patients to maximally use the physical strength they possess is required. To realize this objective, it is important that a robot assists patients according to their body movement and by their intentions. However, in previous studies, general assistive robots helped patients by using a fixed motion reference pathway in spite of their original intention, and as a result, these robots failed to use the physical strength of the patients. In our previous study, we investigated the posture tolerance during a standing motion. In this tolerance, patients could stand by own muscle strength with stable posture. Thus, as the next step, this paper proposes assistance force control scheme which considers the investigated posture tolerance. Our robot generated assistance force, which lead the voluntary movement with their remaining physical strength within investigated range, by combining position control and force control. A prototype assistive robot, based on the proposed idea was fabricated to help patients stand up safely using the maximum of their remaining physical strength.

Artificial intelligence (AI)-based robots have become popular in various fields, thereby increasing the demand for care robots. Such care robots recognize or estimate factors such as human states and then perform actions depending on the estimation results. If the humans cooperating with robots do not understand robot functions well, the task will not be performed appropriately. Additionally, it is possible that the estimation may be incorrect. Robots may make mistakes, and there is a risk that these mistakes may not be understood by humans. In such cases, robots are not useful, and this may hinder the cooperation between humans and robots. There are several ways to deal with this issue including improving estimation and information representation. We can know what is important to design care robots by analyzing the influence of factors including accurate estimation and contents and timing of information representation. We developed a robot for analysis that can support a human during standing, by raising its armrest. The developed robot raises its armrest when the user leans on it. In the nursing-care field, verbal communication is important. Hence, we also adopt a verbal guidance for information representation. Verbal guidance to encourage a user to stand up and countdown timer representations are adopted. Initially, an experiment is conducted to validate the usability of the system that acts according to considerably accurate estimations. The experimental results show that system without verbal guidance causes anxiety to humans and the system becomes not useful, even if the human state is detected accurately. Furthermore, we determine the appropriate content and timing of verbal guidance based on the results. Subsequently, we conduct an experiment to confirm that the proposed method is applicable under imperfect estimations.

Catabolism of the branched-chain amino acids (BCAAs: leucine, isoleucine, and valine) is regulated by the branched-chain α-ketoacid dehydrogenase (BCKDH) complex, which in turn is regulated by phosphorylation catalyzed by BCKDH kinase (BDK). Thiamine pyrophosphate (TPP) is required as a coenzyme for the E1 component of the BCKDH complex and can also bring about activation of the complex by inhibiting BDK. The present study shows that free Ca^2+ in the physiological range greatly increases the sensitivity of BDK to inhibition by TPP (IC50 of 2.5 μM in the presence of 1 μM free Ca^2+). This novel mechanism may be responsible for the stimulation of BCAA oxidation by conditions that increase mitochondrial free Ca^2+ levels, e.g. in skeletal muscle during exercise., ファイル公開：2019-10-12

This paper proposes a novel sitting assistance robot, which considers the posture tolerance of its user. The standing and sitting motion are different essentially because the standing is lifting motion against gravitational force and sitting is posture coordination to sitting position according to the gravity. Therefore, the robot should lead the patient’s posture within a stable range during sitting and the required performance is different from standing assistance. However, in previous studies, conventional assistive robots used the sitting motion which is "reverse" motion of standing. Furthermore, these robots helped patients by using a fixed motion reference pathway in spite of their original intention, and as the results, these robots failed to assist by confliction between their intended motion and reference path. Therefore, we propose a novel sitting assistance robot, which allows its user to move their body within a prescribed degree of posture tolerance during the process of moving from a standing to a sitting position. Our key findings cover two fundamental research topics. One is the investigation into posture tolerance during a sitting motion. The other topic is a novel assistance control algorithm that considers the investigated posture tolerance by combining position control and force control. A prototype assistive robot, based on the proposed idea was fabricated to help patients sitting down safely according to their original intention.

This paper proposes a novel sitting assistance robot, which considers the posture tolerance of its user. The standing and sitting motion are different essentially because the standing is lifting motion against gravitational force and sitting is posture coordination to sitting position according to the gravity. Therefore, the robot should lead the patient’s posture within a stable range during sitting and the required performance is different from standing assistance. However, in previous studies, conventional assistive robots used the sitting motion which is “reverse” motion of standing. Furthermore, these robots helped patients by using a fixed motion reference pathway in spite of their original intention, and as the results, these robots failed to assist by confliction between their intended motion and reference path. Therefore, we propose a novel sitting assistance robot, which allows its user to move their body within a prescribed degree of posture tolerance during the process of moving from a standing to a sitting position. Our key findings cover two fundamental research topics. One is the investigation into posture tolerance during a sitting motion. The other topic is a novel assistance control algorithm that considers the investigated posture tolerance by combining position control and force control. A prototype assistive robot, based on the proposed idea was fabricated to help patients sitting down safely according to their original intention.

This paper proposes a novel standing assistance robot, which considers the posture tolerance of its user. In previous studies, conventional assistive robots did not require patients to use their own physical strength to stand, which leads to decreased strength in the elderly. Therefore, an assistive robot that allows patients to maximally use the physical strength they possess is required. To realize this objective, it is important that a robot assists patients according to their body movement and by their intentions. However, in previous studies, general assistive robots helped patients by using a fixed motion reference pathway in spite of their original intention, and as a result, these robots failed to use the physical strength of the patients. Therefore, we propose a novel standing assistance robot, which allows its user to move their body within a prescribed degree of posture tolerance during the process of moving from a sitting to a standing position. Our key findings cover two fundamental research topics. One is the investigation into posture tolerance during a standing motion. The other topic is a novel assistance control algorithm that considers the investigated posture tolerance by combining position control and force control. A prototype assistive robot, based on the proposed idea was fabricated to help patients stand up safely using the maximum of their remaining physical strength.

This paper proposes a novel standing assistance scheme that guides a subject to adopt a suitable posture using intended movements. In much previous research, an assistive robot requires the patient to understand the standing reference beforehand and generally, the subject learns the standing motion used by the robot. However, for practical use, a patient should be able to use an assistive robot without special prior knowledge. Nursing specialists also guide their patients with an intended movement. For example, when they incline a patient's upper body before lifting it up, they guide the patient's body with a special moving pattern. Moving in this way is based on their experience and expertise and, in fact, the patient moves according to the motion intended by the nursing specialist. In this paper, we investigate what type of motion guides a patient, and we develop a standing assistance scheme that guides the patient to stand in the intended way. The effectiveness of the proposed method is verified by experiments with our prototype.

Catabolism of the branched-chain amino acids (BCAAs: leucine, isoleucine, and valine) is regulated by the branched-chain α-ketoacid dehydrogenase (BCKDH) complex, which in turn is regulated by phosphorylation catalyzed by BCKDH kinase (BDK). Thiamine pyrophosphate (TPP) is required as a coenzyme for the E1 component of the BCKDH complex and can also bring about activation of the complex by inhibiting BDK. The present study shows that free Ca

We developed a robot patient for patient transfer training for simulating a patient’s performance during patient transfer and for enabling nurses to practice their nursing skills on it. To realize the robot patient, we focused on addressing the problems of designing its limb actions to enable it to respond to nurses’ operations. RC servos and electromagnetic brakes were installed in the joints to enable the robot to simulate a patient’s limb actions, such as embracing and remaining standing. To enable the robot to automatically respond to nurses’ operations, an identification method for these operations was developed that used voice commands and the features of the limbs’ posture measured by angle sensors installed in the robot’s joints. The robot patient’s performance was examined by a control test in which four experienced nursing teachers performed patient transfer with the robot patient and a human-simulated patient. The results revealed that the robot patient could successfully simulate the actions o...

Various assistive machines have been developed to prevent falling accidents of the elderly. In order to achieve advanced support using robot technology, it is important to acquire data or real-time state estimation of user's various motions. However, a lot of expensive and sophisticated sensors utilized to estimate user's state accurately are difficult to use in general households or institutions. In this article, we propose a method to estimate the user's state utilizing a few inexpensive and simple sensors. We focused on CoG (Center of Gravity) to estimate user's state, but when utilizing less sensors than required to calculate the human link model parameters, the position of CoG is underspecified. Then we considered the range of value of unknown parameters to calculate candidates of CoG. The range of CoG candidates can become narrow enough to estimate human state in real-time by properly selecting and placing the sensors. Therefore, the evaluation of CoG candidates allows us to determine where and which sensors to set when designing assistive robots. We firstly selected some sensors which can be generally found on assistive machines, and we created sets of measurements using the number of unknown parameters. From the result of the experiment using a motion capture system, we confirmed that the range of the candidates was considerably narrow when using some of the created measurement sets. We validated the proposed method to estimate user's CoG candidates by actually placing the sensors according to the designed measurement sets and confirmed that the CoG candidates corresponded to those obtained using the motion capture system.

This paper proposes a robotic walker with a standing or sitting assistance function. Although many assistance devices in previous works are specialized in only standing assistance or walking assistance, users need standing, walking and sitting assistance continuously from the same device. Our system focuses on domestic use for people who need nursing in their daily life such as elderly people. To realize an assistive robotic system for “a real world usage,” we design it considering safety, practicality and low cost. Our developed assistive system consists of a powered walker and a standing assistance manipulator. Its size is small enough for using in a narrow room such as a bathroom. Furthermore, when proposed robotic walker assists a standing motion, it uses not only an actuator for lifting up direction but also actuators of a powered walker for stabilizing its user. This means our proposed walker realizes both standing and walking assistance with minimum actuators and its cost is practically low. The performance of our proposed system is verified by experiments using our prototype with elderly or handicapped subjects.

The purpose of this study was to investigate the characteristics of cooperative rhythm production between three people and the effect of cross-feedback between people on the cooperation. We conducted an experiment in which two mutually isolated followers simultaneously performed a synchronized-finger-tapping task with a human leader or metronome producing constant tempo. The followers performed this task with or without tapping timing information of the other follower. The leaders were asked to tap their finger to keep constant tempo with or without the tapping time information of followers. The cross-feedback between followers enlarged synchronization error. The cross-feedback between a leader and followers shortened their inter-tap intervals (ITIs) and decreased the standard deviations of ITIs. These results suggest that the cross-feedback between people in synchronized tapping did not contribute the accuracy of timing of tapping but the variability of tapping timing.

Accumulating evidence indicates a pivotal role for neuroinflammation in ischemic and excitotoxic brain injury. Cytokine-induced neutrophil chemoattractant-1 (CINC-1) is a CXC chemokine implicated in the infiltration of inflammatory cells into the brain parenchyma. In this study, we investigated the effect of N-methyl-D-aspartate (NMDA)-induced neuronal injury on CINC-1 production in the organotypic cortico-striatal slice cultures. Treatment with 50 μM NMDA for 3 – 4 h caused devastating neuronal damage and increased CINC-1 production. Immunohistochemical analysis revealed that the CINC-1 immunoreactivity was predominantly detected in astrocytes. NMDA failed to induce CINC-1 production in enriched astrocyte cultures or neuron-depleted slice cultures, suggesting that NMDA acted on neuronal cells to induce astrocytic CINC-1 production. NMDA-induced CINC-1 mRNA expression was significantly inhibited by U0126, a mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase (MEK) inhibitor. These results suggest that NMDA-evoked neuronal injury induced astrocytic CINC-1 production via a MEK/ERK signaling pathway. Manipulation of this signaling pathway may serve as a target for suppressing neuroinflammation and, thereby, treating ischemic brain injury. Keywords:: astrocyte, chemokine, N-methyl-D-aspartate (NMDA), mitogen-activated protein (MAP) kinase, organotypic slice culture

Pain is an unpleasant sensory and emotional experience. The neural systems underlying the sensory component of pain have been studied extensively, but we are only beginning to understand those underlying its affective component. The bed nucleus of the stria terminalis (BNST) has been implicated in stress responses and negative affective states, such as anxiety, fear, and aversion. Recently, we demonstrated the crucial role of the BNST in the negative affective component of pain using the conditioned place aversion (CPA) test. In the present study, we investigated the involvement of the β-adrenoceptor–protein kinase A (PKA) signaling pathway within the BNST, in particular, within the ventral part of the BNST (vBNST), in pain-induced aversion in male Sprague Dawley rats.In vivomicrodialysis showed that extracellular noradrenaline levels within the vBNST were significantly increased by intraplantar formalin injection. Using the CPA test, we found that intra-vBNST injection of timolol, a β-adrenoceptor antagonist, dose-dependently attenuated the intraplantar-formalin-induced CPA (F-CPA) without reducing nociceptive behaviors. Experiments with subtype-selective antagonists demonstrated the essential role of β2-adrenoceptors in F-CPA. Intra-vBNST injection of isoproterenol, a β-adrenoceptor agonist, dose-dependently produced CPA even in the absence of noxious stimulation. This isoproterenol-induced CPA was reversed by the coinjection of Rp-cyclic adenosine monophosphorothioate (Rp-cAMPS), a selective PKA inhibitor. Furthermore, intra-vBNST injection of Rp-cAMPS dose-dependently attenuated the F-CPA. Together, these results suggest that PKA activation within the vBNST via the enhancement of β-adrenergic transmission is important for the negative affective component of pain.

In this paper, we propose a method to assess an extent of anomaly state of human using a walker-type support system. The elderly and the handicapped people use the walker-type support system to keep their balance and support their weight. Although the walker-type support system is easy to move based on the applied force of the user, several accidents such as falling and colliding with the obstacle have been reported. The anomaly state that causes a severe injury of the user should be detected before accident and the walker-type support system should prevent such accidents. In this paper, we focus on assessing the extent of the anomaly state of the user based on the statistical analysis of the applied force of the user. This research models the applied force of the user in real time by using the Gaussian Mixture Model (GMM), and we determine each parameter of GMM statistically. In addition, we assess the extent of the anomaly state of the user by using the Hellinger score, which can compare the data set of the normal state with that of anomaly state. The proposed method is applied to developed walker-type support system with simple force sensor, and we conduct the experiments in the several walking states and the environmental conditions.

The use of granular steelmaking slag as a substitute for natural sand in the construction of tidal flats was investigated. Using an intertidal flat simulator, we evaluated dephosphorization slag mixed with 8% by dry weight of dredged sediment (DPS+DS) as a basal medium for the growth of benthic macro- and microalgae in comparison with silica sand mixed with 8% dredged sediment (SS+DS). Species compositions of macro- and microalgae were distinctly different between DPS+DS and SS+DS. The mean dry weight of macroalgae on DPS+DS was three orders of magnitude higher than that on SS+DS. Sediment shear strength and pH were higher in DPS+DS than in SS+DS or in the sediment of natural tidal flats. These results suggest that DPS contributes to changing the sediment environment, thereby changing the algal composition compared to the composition on natural tidal flats.

Cytokines and chemokines were originally identified as essential mediators for inflammatory and immune responses. Enhanced production and release of cytokines/chemokines are observed also in the central nervous system (CNS) under diverse pathological conditions. There is growing evidence showing that brain cytokines/chemokines play crucial roles in the neuro-glio-vascular interaction underlying the pathology of various brain disorders and therefore are potential targets for development of novel and effective therapeutics for CNS diseases. Here the evidence of the involvement of cytokines/chemokines in ischemic brain injury and pain is reviewed. Keywords:: interleukin, astrocyte, microglia, excitotoxicity, neuro-glio-vascular interaction

Peroxisome proliferator-activated receptors (PPARs) are ligand-dependent transcription factors which belong to the nuclear receptor family. We examined whether PPARalpha agonists and resveratrol, a polyphenol contained in grapes, protect the brain against ischemia. To investigate whether resveratrol activates PPARs, we performed a cell-based transfection activity assay using luciferase reporter plasmid. PPARalpha and PPARgamma were activated by resveratrol in primary cortical cultures and vascular endothelial cells. Resveratrol (20 mg/kg, 3 days) reduced infarct volume by 36% at 24 h after middle cerebral artery occlusion in wild-type mice. The PPARalpha agonists fenofibrate (30 mg/kg, 3 days) and Wy-14643 (30 mg/kg, days) exerted similar brain protection. However, resveratrol and fenofibrate failed to protect the brain in PPARalpha knockout mice. The data indicate that PPARalpha agonists protect the brain through PPARalpha.

Half-Heusler-type compounds have gained increasing attention as promising thermoelectric materials. In the present work, a focus is placed on TiNiSn with additions of Hf, Zr, Si, or Pt. Nominally stoichiometric TiNiSn alloys were prepared using arc melting and subsequent annealing at 1,073 K for 2 weeks. The thermoelectric properties, such as thermoelectric power, electrical resistivity, and thermal conductivity, were measured in a temperature range from 300 K to 1,000 K. As-cast materials show metallic transport properties, while annealed ones exhibit semiconductor behavior. Microstructures of TiNiSn alloys basically consist of nonequilibrium four-phase; half-Heusler TiNiSn, Heusler TiNi2Sn, metallic Ti6Sn5, and Sn solid solution. The volume fraction of the half-Heusler TiNiSn phase significantly increases by annealing. It is revealed that coexisting metallic phases degrade the thermoelectric properties of half-Heusler TiNiSn. Alloy additions strongly affect not only thermoelectric properties but also phase stability. The thermal conductivity of TiNiSn alloys with alloy additions decreases because of the point-defect phonon scattering.

In the cellular slime mold Dictyostelium discoideum, Countin and Countin2 proteins are thought to control the size of the multicellular structure since the countin- strain forms a huge fruiting body and countin2- strain forms a small fruiting body. Recently, the countin3 gene encoding a polypeptide homologous to Countin and Countin2 was identified in the D. discoideum genome. The countin3- strain formed a 1.8-fold larger number of aggregates, resulting in smaller fruiting bodies compared to those formed by the wild-type. The extent of cell-cell adhesion was reduced in the mutant, indicating that Countin3 protein regulates size by controlling the amounts of proteins responsible for the adhesion.