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61.
Y Ikeda Y Fujii M Umemura T Hatakeyama M Morita M Yamazaki 《Canadian Metallurgical Quarterly》1996,746(2):255-260
We have recently chosen to undertake a comprehensive evaluation of the modulation of gene expression by oxidative stress, using mRNA as a marker. Our model system is HA-1 hamster fibroblasts, using conditions under which we observe an adaptive response. Under these conditions, the HA-1 cells respond to a minimally toxic "pretreatment" dose of hydrogen peroxide by synthesizing RNAs and proteins that protect them against subsequent exposure to a highly cytotoxic concentration of hydrogen peroxide. Using the differential display technique to screen for modulated RNAs, we have recently reported an RNA species, adapt15/gadd7, whose steady-state level is significantly induced by a pretreatment dose of hydrogen peroxide (D. R. Crawford, G. P. Schools, S. L. Salmon, and K. J. A. Davies (1996) Arch. Biochem. Biophys. 325, 256-264). Here we report a second induced mRNA, designated adapt33. Two homologous adapt33 mRNAs were revealed by Northern blot hybridization. Both of these species were inducible by hydrogen peroxide, and they were sized at 1.46 and 0.99 kb. These inductions appeared to be dependent upon calcium, occurred as early as 90 min, and were maximal at 5 h. Cell fractionation revealed that a significant proportion of adapt33 RNA is associated with active translation. adapt33 is a novel sequence, as determined by cloning, sequencing, and GenBank analysis. adapt33 represents a new oxidant-inducible RNA and marker of cellular oxidative stress and a potential aid in the study, detection, and possible therapy of oxidant-related disorders. 相似文献
62.
Kazuto Okazaki Tatsuya Ogiwara Dongshin Yang Kentaro Sakata Ken Saito Yoshifumi Sekine Fumio Uchikoba 《Artificial Life and Robotics》2011,16(2):229-233
This article presents the micro-electro-mechanical systems (MEMS) microrobot which demonstrates locomotion controlled by hardware
neural networks (HNN). The size of the microrobot fabricated by the MEMS technology is 4 × 4 × 3.5 mm. The frame of the robot
is made of silicon wafer, and it is equipped with a rotary-type actuator, a link mechanism, and six legs. The rotary-type
actuator generates rotational movement by applying an electrical current to artificial muscle wires. The locomotion of the
microrobot is obtained by the rotation of the rotary-type actuator. As in a living organism, the HNN realized robot control
without using any software programs, A/D converters, or additional driving circuits. A central pattern generator (CPG) model
was implemented as an HNN system to emulate the locomotion pattern. The MEMS microrobot emulated the locomotion method and
the neural networks of an insect with the rotary-type actuator, the link mechanism, and the HNN. The microrobot performed
forward and backward locomotion, and also changed direction by inputting an external trigger pulse. The locomotion speed was
0.325 mm/s and the step width was 1.3 mm. 相似文献
63.
Ikuro Mizumoto Daisuke Ikeda Tadashi Hirahata Zenta Iwai 《Control Engineering Practice》2010,18(2):168-176
This paper deals with the design of an adaptive PID control system with a parallel feedforward compensator (PFC) for discrete-time SISO systems and its application to water level control of a 3-tank system. The proposed method utilizes the characteristics of almost strict positive realness (ASPR) of the controlled plant. A conventional design scheme of a PFC which realizes an ASPR augmented controlled plant is also proposed. Further it is shown that the introduction of an internal model improves the control performance of the control system with the PFC. The effectiveness of the proposed method is confirmed through water level control experiments on a three-tank SISO system. 相似文献
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The model of self-organized criticality (SOC) is a useful tool to understand the complexity of natural systems in the form of the artificial life and the artificial market. However, SOC remains the question what guarantees the criticality even though the natural systems seem to keep itself in the critical state. In this paper, we focus on the locality of interaction in zero-intelligence plus (ZIP) model. The extremely localized interaction changes the behavior of the ZIP model from equilibrium to intermittency. Although the original ZIP model falls into unstable with some noise, extremely localized interaction model archives robust intermittency against the noise parameter. Further, the statistical property of intermittent behavior shows the power-law nature. 相似文献
66.
Makoto Sakamoto Kaoru Kajisa Naoko Tomozoe Takao Ito Hiroshi Furutani Michio Kono Satoshi Ikeda 《Artificial Life and Robotics》2008,13(1):61-64
In 1997, C.R. Dyer and A. Rosenfeld introduced an acceptor on a two-dimensional pattern (or tape), called the pyramid cellular acceptor, and demonstrated that many useful recognition tasks are executed by pyramid cellular acceptors in time proportional to the
logarithm of the diameter of the input. They also introduced a bottom-up pyramid cellular acceptor which is a restricted version of the pyramid cellular acceptor, and proposed some interesting open problems of the bottom-up
pyramid cellular acceptors. On the other hand, we think that the study of threedimensional automata has been meaningful as
the computational model of three-dimensional information processing such as computer vision, robotics, and so forth. In this
paper, we investigate about bottom-up pyramid cellular acceptors with three-dimensional layers, and show their some accepting
powers.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
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