海底地震観測による日本海溝中部(福島県沖)の地震学的地域性

University of Tokyo (東京大学

Earthquake Observation by the SAO Service VSAT and a Hybrid Independent Power Supply

＜短報

Real-time Phase Correction of Acausal Seismic Data Using Allpass Filter

Earthquake Observation Center (EOC), ERI is using Δ-Σ type AD converters with FIR digital filters at several stations of its seismic observation network. These filters produce acausal signals before the arrival of real seismic waves and this had been a problem in phase picking work. We constructed an allpass filter to minimize this acausal signal and introduced it to the automatic data processing system of EOC. The acausal signals are reduced significantly, although a few percent of them still remain in the worst case.＜論説

Novel characteristics of the temporal transition to maximum tongue pressure in Parkinson’s disease: A pilot study

Introduction: The reason why maximum tongue pressure (MTP) decreases in patients with Parkinson’s disease (PD) remains unclear. Repeated measurements of isometric force and MTP may be useful for analyzing muscle wasting and force generation. The purpose of this pilot study was to evaluate the clinical characteristics and temporal transition of MTP in PD and normal control (NC) groups. Methods: There were 18 participants in this study: 10 with PD and 8 NCs. The MTP was measured 20 times at regular intervals. The area under the curve of MTP temporal transitions, time to reach MTP, and total transition time of the tongue pressure (time to return to baseline) were compared between the groups. Results: MTP decreased from baseline in PD subjects. Unlike NCs, PD subjects showed diverse and inconsistent temporal transitions. The decrease in MTP and delays in time to reach MTP and time to return to baseline were significantly greater in PD subjects (p < 0.05), while there was no group difference in area under the curve values. According to repeated-measures ANOVA, MTP was not different over time between PD subjects and NCs. Conclusion: In this study, muscle fatigue did not affect the decrease in MTP seen in PD subjects, or the diversity and inconsistency of the temporal transition in MTP in that group. These findings indicate that the motor control needed for the repeated, identical movements associated with MTP generation may be impaired in PD patients

Seismic Observation on Volcano Summit Area by Optical-Fiber Cable Using Inexpensive Media Converters

＜短報

Establishing a Temporary Seismic Network in and around Mt. Asama, Japan

＜短報