Smad7 inhibits metastasis, possibly by regulating cell-cell adhesion. Systemic expression of Smad7 may be a novel strategy for the prevention of metastasis of advanced cancers.

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Since the superconductor layers of YBCO-coated conductors are very thin, the ac loss of coated conductors is dominated by the magnetic flux density normal to the conductor face. In cables, most of the normal magnetic flux component is generated near gaps between coated conductors. Although the effects of gaps are significant, there are few reports on the electromagnetic field analysis of cables with spiral structures carried out while taking the gap effect into consideration. In a finitely long cable with a spiral structure, the electromagnetic field is naturally periodic along the cable axis. In a two-layer cable, the simplest period along the cable axis is the least common multiple of the spiral pitches in the inner and outer layers. However, we verified that there is a shorter period, and the same electromagnetic field distribution appears in all conductors of the same layer. Using these periodicities, we developed a three-dimensional model for the analysis of two-layer cables with a spiral structure. Current distributions of cables were analyzed using this model, and ac losses were calculated. In addition, these results were compared with ac losses calculated by two-dimensional analysis performed on the cross section of a cable. It was verified that the ac loss in a cable is correctly calculated by the 2D model when the spiral pitch is long enough. However, in the case of a tightly twisted cable, the ac losses calculated by the 2D model include some errors caused by an approximation in which the spiral structure is ignored.

We have developed a noncontact-type centrifugal blood pump with hydrodynamic bearings and a semi-open impeller for mechanical circulatory assist. The impeller is levitated by an original spiral-groove thrust bearing and a herringbone-groove journal bearing, without any additional displacement-sensing module or additional complex control circuits. The pump was improved by optimizing the groove direction of the spiral-groove thrust bearing and the pull-up magnetic force between the rotor magnet and the stator coil against the impeller. To evaluate hemocompatibility, we conducted a levitation performance test and in vitro hemocompatibility tests by means of a mock-up circulation loop. In the hemolysis test, the normalized index of hemolysis was reduced from 0.721 to 0.0335 g/100 L corresponding to an expansion of the bearing gap from 1.1 to 56.1 microm. In the in vitro antithrombogenic test, blood pumps with a wide thrust bearing gap were effective in preventing thrombus formation. Through in vitro evaluation tests, we confirmed that hemocompatibility was improved by balancing the hydrodynamic fluid dynamics and magnetic forces.

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We succeeded to transfer a precise micropattern combining with an ultrasonic vibration in an atmospheric hot embossing on the almost same condition as a vacuum hot embossing. This paper reports the effect of the ultrasonic vibration that was verified experimentally. In the conventional method, a metallic mold and a plastic sheet are heated more than the glass transition temperature of the plastic, and the softened plastic is flowed into the pattern only by applying a load. On the other hand, a longitudinal ultrasonic vibration is added in the molding process of an ultrasonic-vibration hot embossing. The synergy effect of the load and the ultrasonic vibration enables flowing of the plastic into a more precise pattern of the metallic mold. The longitudinal wave generated by an ultrasonic vibration system of the frequency 15 kHz and output 900 W. A pattern of the Ni mold used in the experiment was a pyramid hole in which a peak was cut and sidewalls were rounded. Entrance lengths of pyramids were from 100 to 530 lm and its all of the depth were 260 lm. A polycarbonate was chosen with a replication material. Compared with the condition that the ultrasonic vibration was not used, a contact force and a contact time could be reduced to about 1/3 and 1/12, respectively.