In the Usui River, where sediment accumulation has been reduced due to the dam upstream, the soft rocks at the bottom of the river have been exposed. As a result, the riverbed soft rocks have been eroded resulting from slaking and the level of the river bottom is getting lower. This is the cause of problems such as damage to river banks and difficulties in agricultural water intake. In this study, we measure the slaking depth on the soft rock surface happened as a consequence of repetitive drying and water immersion using soft rock samples collected in this area. The results are as follows. One cycle of dry/wet repetition make about 3 mm of granulation on the soft rock surface. The thickness of this granulation become smaller if sufficient drying conditions are not provided. Remaining particles on the surface of the soft rock after slaking seems to delay the granulation. The soil classification of disintegrated particles is also shown.

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The purpose of this study is to evolve the Swedish Weight Sounding test (Hereinafter referred to as the SWS test) results from the conventional " relative index indicating the hardness of the ground " to " values with clear physical meaning " . For this purpose, we analyzed the results of consolidation test, the edge penetration box shear test simulating the SWS test, and the SWS tests using the full-scale embankment. As a result, it was shown that Nsw values of the SWS test are related to the volume compression characteristics of the soil, and that torque values of the SWS test can be estimated by shear force of the edge penetration box shear test. Since these laboratory tests are conducted by controlling the degree of soil compaction, Nsw values and torque values of the SWS test can be associated with the degree of soil compaction. Based on these findings, it was shown that the SWS test results could be used for liquefaction risk assessment and ground subsidence prediction using the degree of soil compaction as an index.

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We here describe the characteristics of genome mutations found in cancer cells.

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Generalized entropy-production (GEP) is a measure of increased disorderliness in natural systems. In this article, a novel GEP is proposed, which is formulated as a quadratic form based on Jacobian matrix derived from the ordinary differential equations for the target systems. The proposed GEP has an advantage associated with eigenvalues of the Jacobian matrix, which characterizes the perturbation response of the target system. The results showed that, in numerical experiments for four biological regulatory systems the proposed GEP was consistent with perturbation response such that with the decrease in an average of the proposed GEP, the deviation from the steady state by impulsive perturbation has converged fast. The proposed GEP makes the property, a system often transitions to a new state with lower entropy, found by Kondepudi and Prigogine in chemical systems is applicable to the four biological regulatory systems.

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Intrinsically disordered proteins are the ones that have intrinsically disordered regions adopting no tertiary structures under the physiological condition. We have been developing a database of intrinsically disordered proteins, IDEAL (https://www.ideal-db.org), for the last decade. In this article, we will look back our activity and introduce IDEAL as the 10th anniversary of IDEAL.

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The treatment for severely ill patient with COVID-19 is a burden to hospital management. When a centrifugal blood pump is replaced with a peristaltic pump in an extracorporeal membrane oxygenation (ECMO) used for respiration failure, the cost would be effectively decreased because the peristaltic pump can be used for long periods without the need to replace expensive parts. Blood in the peristaltic pump flows with moving the roller which compresses fluid within the tube. Under inappropriate occlusion, red blood cells undergo the morphological change and finally hemolysis. To avoid such unfavorable processes, the appropriate occlusion must be kept during the treatment. In this review, we examined the literatures on mechanisms of the changes in morphology dependent on the occlusion and pursued the clue of early change of the morphology.

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In this study, a lightweight upper-limb power-assisted exoskeleton with high backdrivability was developed. Moreover, a motion capture system was adopted to measure and analyze the workspace of the wearer’s upper limb after the exoskeleton was worn. The results were used to evaluate the exoskeleton’s ability to support the wearer’s movement. Furthermore, the force sensor and EMG sensor was used for power assistance, and the effect of the power assistance was evaluated by means of measuring the wearer’s surface electromyography, force, and joint angle signals. Overall, the study showed that the exoskeleton could achieve power assistance and did not affect the wearer’s movements.

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