Effects of Motor Imagery Training on Balance and Gait in Older Adults: A Randomized Controlled Pilot Study.

The aim of this study was to demonstrate the effects of motor imagery training on balance and gait abilities in older adults and to investigate the possible application of the training as an effective intervention against fall prevention. Subjects (n = 34) aged 65 years and over who had experienced falls were randomly allocated to three groups: (1) motor imagery training group (MITG, n = 11), (2) task-oriented training group (TOTG, n = 11), and (3) control group (CG, n = 12). Each group performed an exercise three times a week for 6 weeks. The dependent variables included Path Length of center of pressure (COP)-based static balance, Berg Balance Scale (BBS) score, Timed Up and Go Test (TUG) score, which assesses a person's mobility based on changes in both static and dynamic balance, Falls Efficacy Scale (FES) score, which evaluates changes in fear of falls, and gait parameters (velocity, cadence, step length, stride length, and H-H base support) to evaluate gait. After the intervention, Path Length, BBS, TUG, velocity, cadence, step length, and stride length showed significant increases in MITG and TOTG compared to CG (p < 0.05). Post hoc test results showed a significantly greater increase in BBS, TUG, and FES in MITG compared with TOTG and CG (p < 0.05). Our results suggest that motor imagery training combined with functional training has positive effects on balance, gait, and fall efficacy for fall prevention in the elderly.

High-Performance Field-Effect Transistor and Logic Gates Based on GaS-MoS2 van der Waals Heterostructure.

This work demonstrates a high-performance and hysteresis-free field-effect transistor based on two-dimensional (2D) semiconductors featuring a van der Waals heterostructure, MoS2 channel, and GaS gate insulator. The transistor exhibits a subthreshold swing of 63 mV/dec, an on/off ratio over 106 within a gate voltage of 0.4 V, and peak mobility of 83 cm2/(V s) at room temperature. The low-frequency noise characteristics were investigated and described by the Hooge mobility fluctuation model. The results suggest that the van der Waals heterostructure of 2D semiconductors can produce a high-performing interface without dangling bonds and defects caused by lattice mismatch. Furthermore, a logic inverter and a NAND gate are demonstrated, with an inverter voltage gain of 14.5, which is higher than previously reported by MoS2-based transistors with oxide dielectrics. Therefore, this transistor based on van der Waals heterostructure exhibits considerable potential in digital logic applications with low-power integrated circuits.

Flexible and Transparent Thin-Film Transistors Based on Two-Dimensional Materials for Active-Matrix Display.

Two-dimensional (2D) materials have attracted significant attention because of their outstanding electrical, mechanical, and optical characteristics. Because all of the conducting (graphene), semiconducting (molybdenum disulfide, MoS2), and insulating (hexagonal boron nitride, h-BN) components can be constructed from 2D materials, thin-film transistors based on 2D materials (2D TFTs) have been developed. However, scaling-up is necessary for these technologies to go beyond their initial implementation using the mechanical exfoliation method. Furthermore, it would be beneficial to find a method to realize high flexibility and/or transparency to their full potential. In this study, large-scale, flexible, and transparent 2D TFTs are developed and demonstrated as a backplane in active-matrix organic light-emitting diodes (AMOLEDs). With the optical chemical vapor deposition of the 2D materials, flexible (bending radius < 1 mm) and transparent (transmittance > 70%) TFTs with high electrical performances (mobility ≈ 10 cm2 V-1 s-1, on/off current ratio > 106) can be achieved. Furthermore, 2D TFTs are integrated into OLEDs by connecting the source electrode of the TFT to the anode of the OLED via a single graphene film, thus demonstrating pixel-by-pixel driving through a 2D TFT array in an active-matrix configuration.

The effect of motor imagery training for trunk movements on trunk muscle control and proprioception in stroke patients.

[Purpose] The present study was conducted to evaluate the effect of motor imagery training for trunk movements on trunk muscle control and proprioception in stroke patients. [Subjects and Methods] A total of 12 study subjects were randomly assigned to the experimental group (a motor imagery training group) and the control group (a neurodevelopmental treatment, NDT) group. The two groups were treated five times (30 minutes each time) per week for 4 weeks. The experimental group underwent imagery training for 10 minutes and trunk control centered NDT for 20 minutes and the control group underwent only trunk control centered NDT for 30 minutes. The trunk muscle activity and the position sense of the subjects were evaluated before and after the intervention. [Results] The two groups showed significant improvements in muscle activity after the intervention. Only the experimental group showed significant improvements in proprioception. The experimental group showed significant improvements in the variations of muscle activity and proprioception compared to the control group. [Conclusion] Motor imagery training for trunk movements can be effectively used to improve trunk muscle activity and proprioception in stroke patients.