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Background: Falls and fractures due to impaired balance in patients with Alzheimer’s disease (AD) have an adverse effect on the clinical course of the disease. Objective: To evaluate balance impairment in AD from the viewpoint of vestibular functional impairment. Methods: The subjects were 12 patients with AD, 12 dementia-free elderly adults, and 12 younger adults. Vestibular function was assessed using a stepping test, caloric nystagmus, and a visual suppression (VS) test. Results: The stepping test was abnormal in 9 of the 12 patients in the AD group. An abnormal stepping test was not associated with self-reported dizziness or tendency to fall. Significant VS abnormalities were present in the AD group. The suppression rate of VS was lower in AD patients with either a tendency to fall or constructional apraxia than in AD patients without either. The velocity of the rapid phase of caloric nystagmus before the VS test was similar in the AD group and the elderly control group. Significant abnormalities of both caloric nystagmus and VS were not present in either the elderly or the younger control groups. Conclusion: AD could involve impairments in the vestibular control of balance. The VS test is useful for assessing the tendency to fall in AD. Impairment of VS in AD might arise from cerebral vestibular cortex impairment rather than comorbid peripheral vestibular disorders.

Purpose. We evaluated improvements in gait after using the Hybrid Assistive Limb (HAL®) exoskeleton robot in a patient with late-onset neurological deterioration of lower extremity function after undergoing thoracic spine surgery for a myelopathy due to ossification of the ligamentum flavum. Case Presentation. A 70-year-old man participated in ten 20 min sessions of HAL intervention, twice weekly for five weeks. The effects of each HAL session were evaluated based on changes in performance on the 10 m walk test (10 MWT), lower limb kinematics quantified from motion capture, and the activation ratio of the gastrocnemius, measured before and after the intervention. Muscle activity was recorded using surface electromyography and synchronized to measured kinematics. The HAL intervention improved gait speed and step length, with an increase in the hip flexion angle during the swing phase and a decrease in the activation ratio of the gastrocnemius. The modified Ashworth scale improved from 1+ to 1 and International Standards for Neurological and Functional Classification of Spinal Cord Injury motor scores from 34 to 49. Conclusion. Intervention using the HAL exoskeleton robot may be an effective method to improve functional ambulation in patients with chronic spinal disorders.

Context: We sought to describe our experience with the Hybrid Assistive Limb® (HAL®) for active knee extension and voluntary ambulation with remaining muscle activity in a patient with complete paraplegia after spinal cord injury. Findings: A 30-year-old man with complete paraplegia used the HAL® for 1 month (10 sessions) using his remaining muscle activity, including hip flexor and upper limb activity. Electromyography was used to evaluate muscle activity of the gluteus maximus, tensor fascia lata, quadriceps femoris, and hamstring muscles in synchronization with the Vicon motion capture system. A HAL® session included a knee extension session with the hip flexor and voluntary gait with upper limb activity. After using the HAL® for one month, the patient's manual muscle hip flexor scores improved from 1/5 to 2/5 for the right and from 2/5 to 3/5 for the left knee, and from 0/5 to 1/5 for the extension of both knees. Conclusion/clinical relevance: Knee extension sessions with HAL®, and hip flexor and upper-limb-triggered HAL® ambulation seem a safe and feasible option in a patient with complete paraplegia due to spinal cord injury.

This questionnaire serves to interview subjects undergoing rehabilitation of joint movement by means of exoskeleton robot HAL (hybrind assistive limbs). The goal is to learn about subjective control strategies during voluntary initiation of joint movement. Questions and multiple-choice answers build on phenomenological introspection. The results of the questionnaire are correlated to a gait score analysis.

This questionnaire serves to interview subjects undergoing rehabilitation of joint movement by means of exoskeleton robot HAL (hybrind assistive limbs). The goal is to learn about subjective control strategies during voluntary initiation of joint movement. Questions and multiple-choice answers build on phenomenological introspection. The results of the questionnaire are correlated to a gait score analysis.

Patients with complete paraplegia after spinal cord injury (SCI) are unable to stand or walk on their own. Standing exercise decreases the risk of decubitus ulcers, osteoporosis, and joint deformities in patients with SCI. Conventional gait training for complete paraplegia requires excessive upper limb usage for weight bearing and is difficult in cases of complete quadriplegia. The purpose of this study was to describe voluntary ambulation triggered by upper limb activity using the Hybrid Assistive Limb® (HAL) in patients with complete quadri/paraplegia after chronic SCI. Four patients (3 men, 1 woman) were enrolled in this study. The mean patient age ± standard deviation was 37.2 ± 17.8 (range, 20-67) years. Clinical evaluation before intervention revealed the following findings: case 1, neurological level C6, American Spinal Cord Injury Association impairment scale (AIS) grade B; case 2, T6, AIS A; case 3, T10 AIS A; and case 4, T11, AIS A. The HAL intervention consisted of 10 sessions. Each HAL session lasted 60-90 min. The HAL electrodes for hip and knee flexion-extension were placed on the anterior and posterior sides of the upper limbs contralaterally corresponding to each of the lower limbs. Surface electromyography (EMG) was used to evaluate muscle activity of the tensor fascia lata and quadriceps femoris (Quad) in synchronization with a Vicon motion capture system. The modified Ashworth scale (mAs) score was also evaluated before and after each session. All participants completed all 10 sessions. Cases 1, 2, and 3 demonstrated significant decreases in mAs score after the sessions compared to pre-session measurements. In all cases, EMG before the intervention showed no apparent activation in either Quad. However, gait phase dependent activity of the lower limb muscles was seen during voluntarily triggered ambulation driven by upper limb muscle activities. In cases 3 and 4, active contraction in both Quads was observed after intervention. These findings suggest that upper-limb-triggered HAL ambulation is a safe and feasible option for rehabilitation in patients with complete quadri/paraplegia caused by chronic SCI.

Purpose: The somatosensory event-related potential N140 is thought to be related to selective attention. This study aimed to compare the somatosensory event-related potential N140 in healthy subjects to that in patients with stroke to determine whether N140 and attentiveness are associated in patients with stroke with or without hemispatial agnosia. Materials and Methods: Normal somatosensory event-related potential N140 values were determined using data from ten healthy subjects. Fifteen patients with stroke were divided into two groups based on the presence of hemispatial neglect. Somatosensory event-related potential N140 components were compared between the two groups. Results: Stimulation of the affected limb in the hemispatial agnosia group resulted in significantly longer N140 latency at the contralateral vs. the ipsilateral electrode. This was the inverse of the relationship observed in normal subjects, with stimulation of the intact side in patients with hemispatial agnosia, and with stimulation of both the intact and affected sides in patients without agnosia. In the hemispatial agnosia group, the peak latency of N140 following stimulation of the affected side was significantly longer than it was following stimulation of the intact side and when compared to that in patients without agnosia. In addition, abnormal N140 peak latencies were observed at the Cz and ipsilateral electrodes in patients with hemispatial agnosia following stimulation of the intact side. Conclusions: These findings suggest that somatosensory event-related potential N140 is independently generated in each hemisphere and may reflect cognitive attention.

Context: The purpose of this report was to describe the improvement in walking ability using the Hybrid Assistive Limb® (HAL®) intervention in the case of a patient with paraplegia after spinal cord injury whose condition deteriorated because of a spinal dural arteriovenous fistula (SDAVF). Findings: A 48-year-old man started the HAL® intervention twice per week (total 10 sessions), after his neurologic improvement had plateaued from 3 to 6 months postoperatively for an SDAVF. During the HAL® intervention, the 10-m walk test (10MWT) without HAL® was performed before and after each session. An electromyography system was used to evaluate muscle activity of both the gluteus maximus (Gmax) and quadriceps femoris (Quad) muscles in synchronization with the Vicon motion capture system. The International Standards for Neurological and Functional Classification of Spinal Cord Injury (ISNCSCI) motor scores of the lower extremities and the Walking Index for Spinal Cord Injury II (WISCI II) score were also assessed to evaluate motor function. The HAL® intervention improved gait speed and cadence during the 10MWT. Before the intervention, both the Gmax and left Quad muscles were not activated. After the intervention, the right Gmax and both Quad muscles were activated in stance phase rhythmically according to the gait cycle. The ISNCSCI motor score also improved from 14 to 16, and the WISCI II scored improved from 7 to 12. Conclusion/clinical relevance: Our experience with this patient suggests that the HAL® can be an effective tool for improving functional ambulation in patients with chronic spinal cord injury.

Soft magnetic powder cores are made by pressurizing and molding pure iron powder covered with insulation film. The material is used as a component of electro-magnetic converter parts essential for automobiles, home electric appliances and electronic equipment. The material permits downsizing and higher performance of such equipment. The recent severer requirements for performance and dimensional accuracy need a new processing technology that warrants the required level of both magnetic performance and surface quality of the material. However in general, processing - grinding - soft magnetic powder cores can give rise to degradation of magnetic performance and/or chipping or plucking of the ground surface due to the mechanical damage of the insulation film and/or loss of structural particles from the material due to the increase in grinding resistance. The authors performed basic studies for various grinding conditions and wheels that could possibly affect the quality of the material with a view to eliminating these problems. As a result, factors that affect the surface quality were identified, and a method that warrants a higher surface quality was proposed.

Introduction/Background We developed Qolo, a new personal mobility device for those with motor disability in their lower limbs It assists sit-to-stand and stand-to-sit postural transitions, as well as navigation in standing posture with hands-free operation Its mechanism to assist postural transition is implemented with passive gas springs without using electric actuators, making it compact, light-weight and low cost The purpose of this study is to report a clinical assessment of the device with people with spinal cord injury (SCI), and investigate plausibility of the device and discuss further technical improvements. Material and method Four participants with SCI (age: 31–52y, 3 males and one female, neurological level: T10-L3, AIS: A-C, MMT Hip Ext: 0-1, Knee Ext: 1–5) were asked to conduct stand-up and sit-down postural transitions using the device ( Fig. 1 ) Feasibility and duration of the assisted motions were evaluated. Results Two of the participants conducted stand-up motion by themselves using the device (duration: 14 and 16 s) The other two needed external posture support The main factor that differed in relation to the ability of performing stand-up motion using the device was MMT Knee Ext; greater than 2 for the group that was able to perform, and 1 for the other All participants conducted sit-down motion by themselves using the device without external support (10–15 s). Conclusion Capability of the device to assist posture transition was shown for some SCI people through the experiment At the same time, greater assistance on the knee joint was found to be necessary Because the device utilizes voluntary control of the trunk to induce assisted motion of knee and ankle joints for posture transition, we considered that assistance for trunk motion would be helpful for them For the next step, we plan to introduce a mechanism for lumbar posture stabilization that can support motion of hip in coordination with knee.

Background Gait disturbance often occurs in stroke survivors. Recovery of walking function is challenging, as some gait disturbance due to hemiparesis often remains even after rehabilitation therapy, presenting a major obstacle towards regaining activities-of-daily-living performance and achieving social reintegration. Objective This study aims to clarify the effectiveness of a walking program involving the wearable Hybrid Assistive Limb (HAL-TS01) robotic exoskeleton for improving walking ability in stroke patients with hemiparesis and stagnant recovery despite ongoing rehabilitation. Methods This is a multicenter, randomized, parallel-group, controlled study (HAL group, n=27; control group, n=27). The study period includes preintervention observation (until stagnant recovery), intervention (HAL-based walking therapy or conventional rehabilitation; 5 weeks), and postintervention observation (2 weeks). Following provision of informed consent and primary registration, the patients undergo conventional rehabilitation for preintervention observation, during which the recovery of walking ability is monitored to identify patients with stagnant recovery (based on weekly assessments using the 10-meter maximum walking speed [MWS] test). Patients with an MWS of 30-60 m/minute and insufficient weekly improvement in MWS undergo secondary registration and are randomly assigned to undergo HAL-based walking therapy (HAL group) or conventional rehabilitation (control group). The primary outcome is the change in MWS from baseline to the end of the 5-week intervention. Results This study began in November 2016 and is being conducted at 15 participating facilities in Japan. Conclusions Assessments of walking ability vary greatly and it is difficult to define the threshold for significant differences. To reduce such variability, our study involves conducting conventional rehabilitation to the point of saturation before starting the intervention. Stagnation in the recovery of walking ability despite conventional rehabilitation highlights the limits of current medical care. The present study may bring evidence that HAL-based therapy can overcome such limitations and induce added recovery of walking ability, which would promote the use of HAL technology in the clinical setting. Trial Registration UMIN Clinical Trials Registry UMIN000024805; https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000028545

In recent years, flat shape motors are desired for many industrial applications such as robot arm, automobiles and so on. Thus, this paper discusses axial gap motors which have advantage for flat shape. In general, axial gap motors have high torque density with flat shape because of its wide air-gap area. Axial gap motors are therefore used for limited space like disk shape instead of radial gap motors which are the most general motor. However, compared with radial gap motors, the acceleration of axial gap motors is relatively lower because of the larger moment of inertia. In this paper, rotor structure to enhance the acceleration of axial gap motors is proposed and analyzed by 3D-FEA. In addition, material for permanent magnet of axial gap motors is properly selected in order to enhance efficiency at high speed and high torque area. Finally, prototypes of both axial and radial gap motor with flat shape are evaluated by some experiments. It is found that proposed axial gap motor can achieve the higher torque and efficiency compared with the radial gap motor with flat shape. Proposed axial gap motor additionally achieved the slightly larger acceleration compared with the radial gap motor.

Recently, locomotor training with robotic assistance has been found effective in treating spinal cord injury (SCI). Our case report examined locomotor training using the robotic suit hybrid assistive limb (HAL) in a patient with complete C4 quadriplegia due to chronic SCI. This is the first report examining HAL in complete C4 quadriplegia.The patient was a 19-year-old man who dislocated C3/4 during judo 4 years previously. Following the injury, he underwent C3/4 posterior spinal fusion but remained paralyzed despite rehabilitation. There was muscle atrophy under C5 level and no sensation around the anus, but partial sensation of pressure remained in the limbs. The American Spinal Injury Association impairment scale was Grade A (complete motor C4 lesion). HAL training was administered in 10 sessions (twice per week). The training sessions consisted of treadmill walking with HAL. For safety, 2 physicians and 1 therapist supported the subject for balance and weight-bearing. The device's cybernic autonomous control mode provides autonomic physical support based on predefined walking patterns. We evaluated the adverse events, walking time and distance, and the difference in muscle spasticity before and after HAL-training using a modified Ashworth scale (mAs). No adverse events were observed that required discontinuation of rehabilitation. Walking distance and time increased from 25.2 meters/7.6 minutes to 148.3 meter/15 minutes. The mAs score decreased after HAL training.Our case report indicates that HAL training is feasible and effective for complete C4 quadriplegia in chronic SCI.

Soft magnetic powder cores are materials manufactured by pressing pure iron powder covered with insulating film into shape. These are widely known soft magnetic materials which are used as essential electromagnetic conversion parts in automobiles and household appliances. In recent years, demand for higher magnetic properties and dimensional precision has been growing with respect to soft magnetic powder cores. It has therefore become necessary to develop a high-efficiency, high-precision finishing method. The issues to be addressed with regard to this kind of method are: (1) the pure iron used in these materials displays ductility resulting in burring and cohesion to machining tools, (2) these materials are green compacts with low binding forces between powder particles and high tendencies towards cracking and gouging, and (3) these materials possess residual pores at levels of several percent thus resulting in microscopically intermittent processing which causes heavy machining tool wear. We have solved these issues through the development of a super-smooth finishing method designed for soft magnetic powder cores.

Soft magnetic powder cores are used for electromagnetic conversion coils, which are essential parts in automotive, home appliance, and other electronics industries. These cores are manufactured through the process of compacting pure iron powder covered with an insulation layer, and are distinguished by high electromagnetic conversion efficiencies. However, soft magnetic powder cores suffer from one problem: their electromagnetic conversion efficiencies drastically decrease when they are subjected to conventional finishing processes. This is directly attributable to the formation of conductive layers on finished surfaces, which significantly reduce the electrical resistance of material surfaces. As a solution to this problem, we developed an electrolytic re-insulation grinding method that finishes materials while applying a current between the material and the grinding wheel. This method regenerates the insulation properties of soft magnetic powder cores through the electrolytic removal of conductive layers formed during finishing, thereby improving electrical resistance. This development enables the finishing of soft magnetic powder cores without compromising their electromagnetic conversion efficiencies.

Introduction/Background Patients with complete paraplegia after spinal cord injury (SCI) are difficult to walk by themselves. Gait training with conventional orthoses requires excessive upper limb usage and is difficult to train knee extensor during ambulation. Robotic devices have recently been used in clinical settings for such patients. Hybrid Assistive Limb (HAL) is a wearable exoskeleton robot that assists the user in voluntary control of knee and hip joint motion by detecting even very weak muscle activities. However, the conventional method using HAL is not applicable in patients with complete paraplegia. The purpose of this study is to describe voluntary gait and voluntary knee extension using Heterotopic Triggered HAL (T-HAL) method in patients with complete quadri/paraplegia after chronic SCI. Material and method Seven patients, 20–67 years old, C6-T11, AIS A-B, were enrolled in this study. HAL session consisted of two parts: the first session was voluntary ambulation using upper limb muscle activation; hip flexion and extension triggered by contralateral muscle activities of anterior deltoid and posterior deltoid and knee flexion and extension triggered by contralateral biceps and triceps brachii, respectively. The second session, for cases who could contract hip flexor, was done for active knee extension using hip flexor activation. Surface electromyography (EMG) was used to evaluate muscle activity of hip flexor and quadriceps femoris (Quad) in synchronization with motion capture. The modified Ashworth scale (mAs) score was evaluated before and after each session. Results In cases 1, 2, mAs score significantly decreased after each session. In all cases, EMG before the intervention showed no activation in either Quad. However, periodic activation of the lower limb muscles was seen during HAL ambulation. In case 3, 4, active contraction in both Quads was observed after intervention. Conclusion These findings suggest that T-HAL method is feasible option for complete quadri/paraplegia with chronic SCI.

We developed Fe/FeSiAl soft magnetic powder cores (SMCs) for realizing the miniaturization and high efficiency of an electromagnetic conversion coil in the high-frequency range (∼20 kHz). We found that Fe/FeSiAl SMCs can be formed with a higher density under higher compaction pressure than pure-iron SMCs. These SMCs delivered a saturation magnetic flux density of 1.7 T and iron loss (W1/20k) of 158 kW/m3. The proposed SMCs exhibited similar excellent characteristics even in block shapes, which are closer to the product shapes.

金沢大学国際基幹教育部, Humans employ various control strategies to initiate and maintain bodily movement. In case that the normal gait function is impaired, exoskeleton robots provide motor assistance during therapy. While the robotic control system builds on kinematic gait functions, the patient’s voluntary efforts to initiate motion also contribute to the effectiveness of the therapy process. However, it is currently not well understood how voluntary initiation as a subjective capacity affects the physiological level of motor control. In order to understand the functional nexus between voluntary initiation and motor control, we interviewed patients undergoing robotic gait rehabilitation with the HAL exoskeleton robot about their experience and command of voluntarily initiating forward gait while using the HAL system. Their reports provide phenomenal evidence for voluntary initiation as a distinct cognitive act that comes as phenomenal performance. Furthermore, phenomenal evidence about the functional relation of intention and initiation correlates with FIM-M gait scores. Based on the assumption that HAL reduces control-related difficulties of voluntarily initiating joint movement, we identified two cognitive control strategies, shaping and compensation of gait, that imply a heterarchic organization of the human system of action control. © 2018 Grüneberg et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

The purpose of this study was to report the improvement of walking ability using Hybrid Assistive Limb (HAL) training in a case of severe thoracic myelopathy caused by ossification of the posterior longitudinal ligament (OPLL). The patient received HAL training 2-3 times per week (10 sessions) beginning on the thirteenth postoperative day. The patient’s walking ability and lower muscles strength were significantly improved. It suggests that HAL training in the early postoperative phase has the potential to be an effective rehabilitation tool to improve functional ambulation in surgically-treated thoracic OPLL patients with inability of walk.

Vascular dementia (VaD) is a heterogeneous clinical entity based on various vascular pathophysiological processes underlying the subtypes of cerebrovascular disease (CVD). Several diagnostic criteria are currently being used for the clinical diagnosis of VaD, but they are mostly more than 10 years old and need to be renovated including the use of functional brain imaging methods such as single photon emission computerized tomography (SPECT). There is a limitation in the diagnosis based on the strict dichotomy between AD and VaD, and the concept of "AD with CVD" or "mixed dementia" should be included in the clinical diagnosis of VaD.

In this paper we present an investigation on the clinical applicability of a newly developed control method for wearable lower limbs exoskeleton robots. The method we developed is based on using body joint synergistic effect, with a walking aid cane to estimate and provide assistance on the affected limb(s). The outcome of hemiparetic persons walking with our developed system shows the subjects immediately being able to walk with the system. The outcome also shows improvement in some gait aspects such as joint range of motion on the knee of the affected side and symmetry ratio in regard to step length. This investigation exhibits the clinical applicability of the proposed method, and prospective gait function improvements of using the system. The prospect of this research contributes to the technology of assisted locomotion, which helps the locomotion of physically challenged people.

Dysphagia can cause serious challenges to both physical and mental health. Aspiration due to dysphagia is a major health risk that could cause pneumonia and even death. The videofluoroscopic swallow study (VFSS), which is considered the gold standard for the diagnosis of dysphagia, is not widely available, expensive and causes exposure to radiation. The screening tests used for dysphagia need to be carried out by trained staff, and the evaluations are usually non-quantifiable. This paper investigates the development of the Swallowscope, a smartphone-based device and a feasible real-time swallowing sound-processing algorithm for the automatic screening, quantitative evaluation, and the visualisation of swallowing ability. The device can be used during activities of daily life with minimal intervention, making it potentially more capable of capturing aspirations and risky swallow patterns through the continuous monitoring. It also consists of a cloud-based system for the server-side analyzing and automatic sharing of the swallowing sound. The real-time algorithm we developed for the detection of dry and water swallows is based on a template matching approach. We analyzed the wavelet transformation-based spectral characteristics and the temporal characteristics of simultaneous synchronised VFSS and swallowing sound recordings of 25% barium mixed 3-ml water swallows of 70 subjects and the dry or saliva swallowing sound of 15 healthy subjects to establish the parameters of the template. With this algorithm, we achieved an overall detection accuracy of 79.3% (standard error: 4.2%) for the 92 water swallows; and a precision of 83.7% (range: 66.6%–100%) and a recall of 93.9% (range: 72.7%–100%) for the 71 episodes of dry swallows., We developed the Swallowscope, a smartphone-based device for the automatic screening, quantitative evaluation and the visualisation of swallowing ability. The device can be used during activities of daily life by simply wearing it around the neck, and the continuous monitoring makes it potentially more capable of capturing aspirations and risky swallow patterns. This device-based swallow assessment could help to develop protocols for the quantitative evaluation of swallowing ability, which are comparable and repeatable. In this paper we discuss the development of the Swallowscope, its evaluation and how the Swallowscope could be used at hospitals or elderly care facilities for the assessment and evaluation of swallowing ability throughout the daytime and/or mealtime.

Rationale: Medial medullary infarction accounts for less than 1% of brain infarctions, and medial medullary infarctions is very rarely caused by antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. Patient concerns: We report the case of a 76-year-old man at low risk of arteriosclerosis who presented with disorders on the left side including gaze-evoked nystagmus, paralysis of the extremities, pyramidal signs, sensory disturbance, and dysesthesia. Brain magnetic resonance imaging also showed right medial medullary infarction. Diagnoses: Medial medullary infarction caused by ANCA-related vasculitis was diagnosed based on mild renal dysfunction and high levels of blood leukocytes, C-reactive protein (CRP), and myeloperoxidase (MPO)-ANCA. Interventions and outcomes: He underwent two 3-day courses of steroid pulse therapy involving daily 1000 mg doses of methylpredonine. He then received 30 mg/day (0.5 mg/kg/day) of prednisolone (PSL) without other immunosuppressants. Levels of MPO-ANCA and the inflammatory marker CRP decreased rapidly a month after admission. Once MPO-ANCA became undetectable, the PSL dose was carefully reduced to 10 mg/day. To treat his paralysis, we provided rehabilitation with a Hybrid Assistive Limb five times starting at a month post-onset. His Barthel index score rose from 45 to 70 points. Lessons: Medullary infarction is mostly caused by arteriosclerosis and vertebral arterial dissection. When systemic inflammatory findings are obtained, ANCA-associated vasculitis should be considered a potential cause, and steroid pulse therapy should be promptly administered.

Dysphagia can cause serious challenges to both physical and mental health. Aspiration due to dysphagia is a major health risk that could cause pneumonia, and even death. As a result, monitoring and managing dysphagia is of utmost importance. This study investigates the development of a smartphone-based device and a feasible real-time swallowing sound processing algorithm for the automatic screening for swallowing ability. The videofluoroscopic swallow study (VFSS), which is considered the gold standard for the diagnosis of dysphagia, is not widely available, expensive and causes exposure to radiation. The screening tests used for dysphagia need to be carried out by trained staff and the evaluations are often non-quantifiable. The Swallowscope we developed is a wearable device based on mobile health, and uses the swallowing sound to quantitatively evaluate swallowing ability. As swallowing sound can be captured continuously and during activities of daily life with minimal intervention, it is an ideal approach to monitor swallowing activities, and its continuous monitoring has a better probability of capturing aspirations and risky swallow patterns. This paper describes the real-time smartphone based algorithm and the application we developed to monitor swallowing activities and evaluates the recognition accuracy by comparing them with VFSS evidence.

The selective vulnerability of distinct neuronal structures is a major feature of Machado-Joseph disease (MJD), also known as spinocerebellar ataxia 3 (SCA3). Vestibular dysfunction is known to be a symptom of MJD, but little is known about precisely when the vestibular system becomes impaired. Using a caloric test, we evaluated vestibular function in 2 MJD patients. One developed the initial symptom 1 year before evaluation, and the other 3 years before evaluation. Neither demonstrated a bilateral response in electronystagmography using ice-cold water irrigation, indicating severe vestibular disturbance. These results suggest that vestibular dysfunction is a symptom that develops very early in MJD and may contribute to unsteady gait as the initial symptom. The vestibular system thus appears to be one of the structures most vulnerable to MJD.

In an ATM network, calls are transmitted through several nodes. At this time, quality control over multiple nodes is considered to be better than quality control for each node independently. In view of such considerations, this paper proposed two control methods regarding discard (loss) quality and call level delay over nodes by carrying quality information in the call. In controlling delay quality, a call delayed at a node is given a higher priority in the next node to recover the delay. Since a cell can remain in one node for a long time, the buffer length of each node is lengthened. This leads to a decrease in the discarding rate. In addition, in discard quality control, the variations in the discard quality of each call can be minimized by performing discard of cells inside a buffer on the basis of the discard quality information of previous nodes when the buffer is full. The effect of these control methods is illustrated by simulation.

In voice packet communication, a fluctuation is produced in the delay time in the network. This makes the packet, which is originally continuous, discontinuous at the receiver, and results in an interruption. The interruption deteriorates the voice quality. Then it is necessary that a delay should be provided at the side of the receiver to absorb the interruption. If the delay for absorbing the fluctuation is too small, the delay cannot sufficiently be absorbed; and if it is too large, the total delay is increased. In either case, the quality of the voice or speech is deteriorated. From such a viewpoint, this paper discusses the absorption of the delay fluctuation of the voice packet. To set the delay for absorbing the fluctuation, the quality of the voice containing interruptions must be evaluated. First, an objective evaluation measure is presented which is well aligned to the subjective evaluation of the deterioration of the voice quality with interruption. A control method to ensure the voice quality above a certain level is presented, which examines the objective evaluation measure for the varying traffic in the network. The method adjusts adaptively the delay for absorbing the delay fluctuation so that the voice quality is kept above a certain reference value.