Development of Gait Rehabilitation System Capable of Assisting Pelvic Movement of Normal Walking

Gait rehabilitation training with robotic exoskeleton is drawing attention as a method for more advanced gait rehabilitation training. However, most of the rehabilitation robots are mainly focused on locomotion training in the sagittal plane. This study introduces a novel gait rehabilitation system with actuated pelvic motion to generate natural gait motion. The rehabilitation robot developed in this study, COWALK, is a lower-body exoskeleton system with 15 degrees of freedom (DoFs). The COWALK can generate multi-DoF pelvic movement along with leg movements. To produce natural gait patterns, the actuation of pelvic movement is essential. In the COWALK, the pelvic movement mechanism is designed to help hemiplegic patients regain gait balance during gait training. To verify the effectiveness of the developed system, the gait patterns with and without pelvic movement were compared to the normal gait on a treadmill. The experimental results show that the active control of pelvic movement combined with the active control of leg movement can make the gait pattern much more natural

Dysphagia in patients with isolated pontine infarction

Little is known about dysphagia after pontine infarction. In this study, we evaluated the incidence of dysphagia after isolated pontine infarction and identified the predictive factors for the occurrence of dysphagia. A total of 146 patients were included in this study. All patients underwent clinical testing for dysphagia within 1 day after admission and at the time of discharge. We compared the incidence of dysphagia between patients with unilateral pontine infarction and those with bilateral pontine infarction. To evaluate the functional status of patients, we investigated their initial modified Rankin Scale (mRS) score and initial National Institutes of Health Stroke Scale (NIHSS) score within 1 day of admission. Of 146 patients, 50 (34.2%) had dysphagia initially within 1 day after admission. At the second evaluation at the time of discharge, dysphagia was diagnosed in 24 patients (16.4%). Patients with bilateral pontine infarction were more likely to present with dysphagia. In addition, clinical severity (in terms of mRS and NIHSS scores) was identified as a predictor of dysphagia in patients with cerebral infarction (multiple binary logistic regression analysis, mRS: P = 0.011, NIHSS: P = 0.004). Dysphagia frequently occurs in patients with isolated pontine infarction. Clinicians should pay particular attention to the occurrence of dysphagia, especially in patients with bilateral pontine infarction or high functional disability

Quantitative agreement of Dzyaloshinskii-Moriya interactions for domain-wall motion and spin-wave propagation

The magnetic exchange interaction is the one of the key factors governing the basic characteristics of magnetic systems. Unlike the symmetric nature of the Heisenberg exchange interaction, the interfacial Dzyaloshinskii-Moriya interaction (DMI) generates an antisymmetric exchange interaction which offers challenging opportunities in spintronics with intriguing antisymmetric phenomena. The role of the DMI, however, is still being debated, largely because distinct strengths of DMI have been measured for different magnetic objects, particularly chiral magnetic domain walls (DWs) and non-reciprocal spin waves (SWs). In this paper, we show that, after careful data analysis, both the DWs and SWs experience the same strength of DMI. This was confirmed by spin-torque efficiency measurement for the DWs, and Brillouin light scattering measurement for the SWs. This observation, therefore, indicates the unique role of the DMI on the magnetic DW and SW dynamics and also guarantees the compatibility of several DMI-measurement schemes recently proposed.Comment: 24 pages, 5 figure