Resistive Switching Memory Cell Property Improvement by Al/SrZrTiO3/Al/SrZrTiO3/ITO with Embedded Al Layer.

The SrZrTiO3 (SZT) thin film prepared by sol-gel process for the insulator of resistive random-access memory (RRAM) is presented. Al was embedded in the SZT thin film to enhance the switching characteristics. Compared with the pure SZT thin-film RRAM, the RRAM with the embedded Al in SZT thin film demonstrated outstanding device parameter improvements, such as a resistance ratio higher than 107, lower operation voltage (VSET = -0.8 V and VRESET = 2.05 V), uniform film, and device stability of more than 105 s. The physical properties of the SZT thin film and the embedded-Al SZT thin-film RRAM devices were probed.

High Linearity Synaptic Devices Using Ar Plasma Treatment on HfO2 Thin Film with Non-Identical Pulse Waveforms.

We enhanced the device uniformity for reliable memory performances by increasing the device surface roughness by exposing the HfO2 thin film surface to argon (Ar) plasma. The results showed significant improvements in electrical and synaptic properties, including memory window, linearity, pattern recognition accuracy, and synaptic weight modulations. Furthermore, we proposed a non-identical pulse waveform for further improvement in linearity accuracy. From the simulation results, the Ar plasma processing device using the designed waveform as the input signals significantly improved the off-chip training and inference accuracy, achieving 96.3% training accuracy and 97.1% inference accuracy in only 10 training cycles.

[Pathophysiological analysis of dropped head syndrome caused by various diagnoses - based on surface EMG findings and responses to physiotherapy].

Dropped head syndrome is seen in various diseases. We investigated its pathophysiological mechanisms with physical and radiological examination, surface EMG and responses to physiotherapy. Subjects had dropped head as a complaint, but their primary diagnoses were various. We investigated 16 cases: 5 cases of Parkinson disease, 5 cases of multiple system atrophy predominant parkinsonism, 3 cases of cervical spondylosis and 3 cases with other diagnoses. We found that patients had common findings such as bulging of cervical muscles, and tonic EMG activities mainly in the extensors in the sitting and standing position, but in the flexors of the neck only in the supine position. Of the 16 cases, 14 were treated with physiotherapy to improve the alignment of the pelvis and whole vertebral column; 6 of the 14 cases (63%) showed remarkable improvement. We conclude that the primary reason of dropped head syndrome is unknown in Parkinson disease and cervical spondylosis, but also that many of the patients have secondary changes in alignment of the skeletomuscular system which could be treated with physiotherapy.

Effect of vibration stimulation on dysbasia of spastic paraplegia in neuromyelitis optica: a possible example of neuronal plasticity.

We analysed the effect of vibration stimulation (VS) on dysbasia of neuromyelitis optica (NMO). The patient was a 36-year-old woman who was diagnosed with NMO and had difficulties in walking. VS was applied to the lower limb muscles on the left, more spastic, side with an ordinary vibrator. The performance of standing up and walking improved with VS. Even with improved performance after VS, the amount of surface EMG of the lower limbs did not increase as a whole, but the EMG patterns among the lower leg muscles changed remarkably. VS produced reciprocity within antagonistic muscles. Variability of EMG amplitudes decreased remarkably during the walking cycle, not only on the vibrated side, but also on the non-vibrated side. The effect lasted longer than several dozen minutes after the cessation of VS. We conjectured that central pattern generator (CPG) and neuronal plasticity were the result of VS.