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The operando hydrogen microscope is an original apparatus that has been developed to visualize the time-dependent permeation of hydrogen through a sample. This apparatus is developed based on an ultrahigh vacuum scanning electron microscope (UHV SEM). The system consists of a lens system to focus ions produced by electron-stimulated desorption (ESD), an ion detector optimized for ESD-signal detection, and a two-dimensional measurement program synchronized with the position information of the electron beam. The developed detectors and electrostatic lenses enable highly sensitive detection of the ions. In this paper, we show the details of the instrumentation of the operando hydrogen microscope. We have succeeded in recording hydrogen and deuterium flowing from the rear of metals to the surface as a series of time-lapse images, showing the time-dependent changes in the surface distribution of hydrogen and deuterium. Deuterium permeation through the metal sample was dynamically visualized at the surface by the two-dimensional mapping of the desorbed ions induced by scanning electron beam irradiation. [ABSTRACT FROM AUTHOR]

Patients with poorly differentiated endometrial cancer show poor prognosis, and effective molecular target-based therapies are needed. Endometrial cancer cells proliferate depending on the activation of HES1 (hairy and enhancer of split-1), which is induced by several pathways, such as the Notch and fibroblast growth factor receptor (FGFR) signaling pathways. In addition, aberrant, ligand-free activation of the FGFR signaling pathway resulting from mutations in FGFR2 was also reported in endometrial cancer. However, a clinical trial showed that there was no difference in the effectiveness of FGFR inhibitors between patients with and without the FGFR2 mutation, suggesting a presence of another signaling pathway for the FGFR activation. Here, we investigated the signaling pathway regulating the expression of HES1 and proliferation of poorly and well-differentiated endometrial cancer cell lines Ishikawa and HEC-50B, respectively. Whereas Ishikawa cells proliferated and expressed HES1 in a Notch signaling-dependent manner, Notch signaling was not involved in HES1 and proliferation of HEC-50B cells. The FGFR inhibitor, NVP-BGJ398, decreased HES1 expression and proliferation of HEC-50B cells; however, HEC50B cells had no mutations in the FGFR2 gene. Instead, HEC-50B cells highly expressed ligands for FGFR2, suggesting that FGFR2 is activated by an autocrine manner, not by ligand-free activation. This autocrine pathway activated Akt downstream of FGFR for cell proliferation. Our findings suggest the usefulness of HES1 as a marker for the proliferation signaling and that FGFR inhibitor may be effective for poorly differentiated endometrial cancers that harbor wild-type FGFR. [ABSTRACT FROM AUTHOR]

Human-operated robotic systems are a suitable solution for supporting industrial and household work from the viewpoints of cost efficiency and the currently available technologies. This paper presents a model reference control approach for a human-operated robotic system. This approach incorporates commands given by a human operator and compensates for mistakes made by the operator in real-time, and is applied to achieve collision avoidance of the robotic manipulator. The proposed method employs inexpensive distance sensors to achieve real-time collision avoidance. The effectiveness of the proposed method is confirmed by an experiment in which an unskilled operator uses the manipulator in a narrow space. [ABSTRACT FROM AUTHOR]

Because the obstacle-avoidance function is indispensable for providing the safe and easy operation of human-operated robotic systems, this paper deals with the obstacle-avoidance control for a human-operated mobile robot in unknown environments. A general type of two-wheeled mobile robot with inexpensive distance sensors to detect obstacles is considered. Because the robot cannot move in arbitrary directions due to a nonholonomic constraint, we propose a model-reference control approach, in which a reference model generates the desired trajectory to satisfy the nonholonomic constraint, and the robot follows the desired trajectory. The reference model has the steering-like and brake-like functions that are adjusted according to the distance-sensor information. The stability of the proposed control system is analyzed with a linear model. The effectiveness of the proposed method is confirmed by experiments in which several operators handle the robot in an environment with obstacles. [ABSTRACT FROM AUTHOR]

SCARA robots generally have two revolute joints and one prismatic joint. One of the fundamental motions of the robots is horizontal transportation of a load by actuating the two revolute joints. Residual vibration of the prismatic joint generally occurs in the transportation, and it should be suppressed. In this paper, we propose an adaptive controller design for the transportation. The controlled object is modeled as a nonlinear double-input quadruple-output system with unknown mass of load. The controlled object is separated into two single-input double-output systems, which allows us to design an integral controller providing performance robustness with respect to estimation error of the mass. Experimental results demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Presents information on the development of a large-scale intergration (LSI) package to meet the requirements of high speed driving in computers. Information on the LSI package; Details on the LSI package; Background information relating to this topic.