Analysis of Differences in Single-Joint Movement of Dominant and Non-Dominant Hands for Human-like Robotic Control.

Although several previous studies on laterality of upper limb motor control have reported functional differences, this conclusion has not been agreed upon. It may be conjectured that the inconsistent results were caused because upper limb motor control was observed in multi-joint tasks that could generate different inter-joint motor coordination for each arm. Resolving this, we employed a single wrist joint tracking task to reduce the effect of multi-joint dynamics and examined the differences between the dominant and non-dominant hands in terms of motor control. Specifically, we defined two sections to induce feedback (FB) and feedforward (FF) controls: the first section involved a visible target for FB control, and the other section involved an invisible target for FF control. We examined the differences in the position errors of the tracer and the target. Fourteen healthy participants performed the task. As a result, we found that during FB control, the dominant hand performed better than the non-dominant hand, while we did not observe significant differences in FF control. In other words, in a single-joint movement that is not under the influence of the multi-joint coordination, only FB control showed laterality and not FF control. Furthermore, we confirmed that the dominant hand outperformed the non-dominant hand in terms of responding to situations that required a change in control strategy.

Experience with pre-diluted plasma exchange therapy for hyperviscosity syndrome.

INTRODUCTION: Plasma exchange therapy (PE) is useful for patients with primary macroglobulinemia and multiple myeloma who present with hyperviscosity syndrome. However, hyperviscous blood may coagulate in the circuit during treatment, and in that case necessitate discontinuation of the treatment. This time, we report that we were able to prevent coagulation in the circuit by adding some ideas during the membrane separation method. METHODS: Physiological saline is injected in front of the plasma separation membrane to pre-dilute the blood, followed by filtration through the plasma separation membrane. RESULTS: As a result of pre-diluting with physiological saline to reduce the viscosity entering the separation membrane, it was possible to process the planned target amount. CONCLUSION: In patients with hyperviscosity syndrome who showed intracircuit coagulation during plasma exchange therapy, devising a predilution method should be considered as one of the ways to continue treatment.